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BAG, J. basic appl. genet. (Online) ; 33(1): 43-49, Oct. 2022. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1420284


ABSTRACT Cytogenetic evidence indicates that Zea, which comprises maize (Z. mays ssp. mays) and its wild relatives, is an allopolyploid genus. Our research group has carried out numerous cytogenetic studies on Zea species, mainly focused on native Argentinian and Bolivian maize landraces. We found a wide inter- and intraspecific genome size variation in the genus, with mean 2C-values ranging between 4.20 and 11.36 pg. For the maize landraces studied here, it varied between 4.20 and 6.75 pg. The objectives of this work are to analyze the causes of genome size variation and to discuss their adaptive value in Zea. This variation is mainly attributed to differences in the heterochromatin located in the knobs and to the amount of interspersed DNA from retrotransposons. Polymorphisms in presence or absence of B-chromosomes (Bs) and the population frequency of Bs are also a source of genome size variation, with doses ranging between one and eight in the landraces analyzed here. Correlation analysis revealed that the percentage of heterochromatin is positively correlated with genome size. In addition, populations cultivated at higher altitudes, which are known to be precocious, have smaller genome sizes than do those growing at lower altitudes. This information, together with the positive correlation observed between the length of the vegetative cycle and the percentage of heterochromatin, led us to propose that it has an adaptive role. On the other hand, the negative relationship found between Bs and heterochromatic knobs allowed us to propose the existence of an intragenomic conflict between these elements. We hypothesize that an optimal nucleotype may have resulted from such intranuclear conflict, where genome adjustments led to a suitable length of the vegetative cycle for maize landraces growing across altitudinal clines.

RESUMEN La evidencia citogenética indica que el género Zea, el maíz (Z. mays ssp. mays) y sus parientes silvestres, posee un origen alopoliploide. Nuestro grupo de investigación ha realizado numerosos estudios en especies de Zea, principalmente en maíces nativos de Argentina y Bolivia. En este género, hallamos una amplia variación inter e intraespecífica en el tamaño del genoma, con valores 2C medios que oscilan entre 4,20 y 11,36 pg. El valor 2C medio de los maíces nativos estudiados varió entre 4,20 y 6,75 pg. Los objetivos de este trabajo son analizar las causas de la variación del tamaño del genoma en Zea y discutir su valor adaptativo. Esta variación se atribuye principalmente a las diferencias en la heterocromatina de los knobs y en la cantidad de ADN intercalado de los retrotransposones. Otras fuentes de variación son los polimorfismos para presencia/ausencia de cromosomas B (Bs) y para la frecuencia poblacional de Bs en las razas analizadas, con dosis que oscilan entre uno y ocho Bs. El porcentaje de heterocromatina se correlaciona positivamente con el tamaño del genoma. Las poblaciones cultivadas en altitudes altas, que son precoces, tienen tamaños de genoma más pequeños que las que crecen en bajas altitudes. Esta información, junto con la correlación positiva observada entre la duración del ciclo vegetativo y el porcentaje de heterocromatina, nos llevó a proponer el rol adaptativo de la heterocromatina. Por otro lado, la relación negativa encontrada entre Bs y knobs heterocromáticos nos permitió proponer la existencia de un conflicto intragenómico entre estos elementos. Hipotetizamos que de este conflicto intranuclear habría resultado el nucleotipo óptimo, donde ajustes genómicos condujeron a una duración adecuada del ciclo vegetativo en las razas de maíz que crecen a lo largo de clines altitudinales.

CienciaUAT ; 16(2): 155-171, ene.-jun. 2022. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1374907


Resumen Las Unidades de Producción Familiar (UPF) están conformadas por capitales natural, físico, financiero, humano y social. Los dos últimos constituyen la base del funcionamiento del resto y de la unidad de producción. En México, Chiapas y la Frailesca, la producción de maíces, particularmente de maíces locales, tiene valor cultural, agronómico y económico. El objetivo de esta investigación fue caracterizar las Unidades de Producción Familiar que cultivan maíces locales en la región Frailesca del estado de Chiapas, sobre la base cultural del manejo de los capitales humano y social. Se estudiaron 80 UPF de 20 comunidades seleccionadas mediante un muestreo por redes. Se utilizó el enfoque Modos de Vida Sustentable como marco de referencia. Se aplicaron entrevistas semiestructuradas y se realizaron observaciones participantes. En el estudio predominaron las familias nucleares con líderes de edad avanzada. Los jóvenes no priorizan la conservación de los maíces locales sino actividades más rentables como la ganadería, los maíces híbridos y el café. Existe un excesivo uso de agroquímicos que afecta los recursos suelo, agua y biodiversidad. Se distinguieron 6 tipos de UPF de acuerdo con sus capitales humano y social. El grupo 3 (G3) mostró un mejor equilibrio entre ambos por la participación familiar, destacándose entre los de mayor experiencia en el cultivo de maíces locales y por tener relaciones locales y de cooperación más sólidas. Se concluye que las UPF presentan características que contribuyen o afectan la conservación de los maíces locales, como la continuidad generacional, el deterioro de los recursos naturales que sostienen el cultivo a través de la fusión de las prácticas tradicionales con las modernas y la dependencia de recursos externos.

Abstract The Family Production Units (FPU) are made up of natural, physical, financial, human and social capital. The last two constitute the basis for the functioning of the rest of the capitals and of the production unit. In Mexico, Chiapas and La Frailesca, the production of corn, and particularly local corn, has cultural, agronomic, and economic value. The objective of this research was to characterize the UPF that cultivate local corn, in the Frailesca region of the State of Chiapas, on the cultural basis of the management of human and social capital. 80 UPF from 20 communities were studied, selected through network sampling. The Sustainable Livelihoods approach was used as a frame of reference. Semi-structured interviews were applied, and participant observations were made. In the predominant study in nuclear families with elderly leaders predominated. Young people do not prioritize the conservation of local corn, but rather more profitable activities such as livestock, hybrid corn and coffee. There is an excessive use of agrochemicals that affects soil, water and biodiversity resources. Six types of UPF were distinguished according to their human and social capital. The third category (G3) shows a better balance between human and social capital due to their family involvement, standingout among those with more experience in growing local corn and having stronger local relationships. It is concluded that the UPF present characteristics that foster or impair the preservation of local corn such as generational continuity, the deterioration of the natural resources that sustain the cultivation through the fusion of traditional and modern practices and dependence on external resources.

Biol. Res ; 552022.
Article in English | LILACS-Express | LILACS | ID: biblio-1383902


Abstract Background: Maize (Zea mays L.) is a widely cultivated cereal and has been used as an optimum heavy metal phytoremediation crop. Metallothionein (MT) proteins are small, cysteine-rich, proteins that play important roles in plant growth and development, and the regulation of stress response to heavy metals. However, the MT genes for maize have not been fully analyzed so far. Methods: The putative ZmMT genes were identified by HMMER. The heat map of ZmMT genes spatial expression analysis was generated by using R with the log2 (FPKM + 1). The expression profiles of ZmMT genes under three kinds of heavy metal stresses were quantified by using qRT-PCR. The metallothionein proteins was aligned using MAFFT and phylogenetic analysis were constructed by ClustalX 2.1. The protein theoretical molecular weight and pI, subcellular localization, TFs binding sites, were predicted using ProtParam, PSORT, PlantTFDB, respectively. Results: A total of 9 ZmMT genes were identified in the whole genome of maize. The results showed that eight of the nine ZmMT proteins contained one highly conserved metallothio_2 domain, while ZmMT4 contained a Metallothio_PEC domain. All the ZmMT proteins could be classified into three major groups and located on five chromosomes. The ZmMT promoters contain a large number of hormone regulatory elements and hormone-related transcription factor binding sites. The ZmMT genes exhibited spatiotemporal specific expression patterns in 23 tissues of maize development stages and showed the different expression patterns in response to Cu, Cd, and Pb heavy metal stresses. Conclusions: We identified the 9 ZmMT genes, and explored their conserved motif, tissue expression patterns, evolutionary relationship. The expression profiles of ZmMT genes under three kinds of heavy metal stresses (Cu, Cd, Pb) were analyzed. In summary, the expression of ZmMTs have poteintial to be regulated by hormones. The specific expression of ZmMTs in different tissues of maize and the response to different heavy metal stresses are revealed that the role of MT in plant growth and development, and stress resistance to heavy metals.

Rev. bras. entomol ; 66(2): e20210121, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1387822


ABSTRACT A 6-year field monitoring study was designed to compare the presence of fall armyworm Spodoptera frugiperda (J. E. Smith), leaf injury, its parasitoids, 100 seed weight, and seed yield of Bt maize hybrids approved for commercialization in the Brazilian market. Field trials were planted in two municipalities, divided into two periods, from 2011 to 2014 (period I), and due to the approval of different Bt hybrids, from 2015 to 2016 (period II). Treatments were Bt, non-Bt maize and all non-Bt maize sprayed with insecticide methomyl. Six Bt-maize hybrids were planted, expressing the following proteins: Cry1Ab, Cry1F, Cry1A.105 (Cry1Ab +Cry1Ac +Cry1F), Cry2Ab2a and Vip3. In 2015 and 2016 Bt Powercore was planted due to its commercial approval. The number of S. frugiperda larvae for most Bt hybrids was lower than on non-Bt hybrids, except for Fórmula TL and Herculex in period II, in both municipalities. In period I, Bt hybrids VT, VT 2 and Viptera showed almost no injury on their leaves, despite the high number of fall armyworm larvae found in plants. Different parasitoids emerged from larvae from Bt and non Bt hybrids: Archytas sp., Campoletis sp., Chelonus sp., Eiphosoma sp. and Ophion luteus. The average 100 seed weight was higher in municipality from Sete Lagoas for all Bt hybrids, non-Bt hybrids and non-Bt hybrids sprayed with methomyl, when compared to Nova Porteirinha during period I. Fórmula TL, non-Bt Fórmula TL sprayed with methomyl, and non-Bt Fórmula TL showed the lowest seed yield in both municipalities and periods.

Braz. j. biol ; 82: e238763, 2022. tab, graf
Article in English | LILACS | ID: biblio-1180734


Abstract We report the discovery that the earwig predator Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) feed on Puccinia polysora Underw uredospore, the causal agent of Southern Rust of Corn (SRC), which is a primary disease affecting the maize crop in Brazil. We performed experiments in laboratory and greenhouse to test the effect of D. luteipes (1st/2nd and 3rd/4th instars, and adults) fungivory on the P. polysora uredospore concentration. All trials showed a significant reduction of the initial concentration of uredospore. There was a reduction in uredospore concentration with increase in number of D. luteipes feeding on them. We also tested the uredospore consumption by quantifying its percentage in the feces of D. luteipes. Nymphs of the 2nd, 4th instar and adults fed 88%, 85%, and 83.8% of the uredospore, respectively. For nymphs of the 3rd instar, the percentage of uredospore consumption (75.6%) was statistically significant compared with the other groups. In greenhouse experiment, at twenty-eight days after plant inoculation with 9.9 x 104 uredospores, the percentage of uredospore consumption was 81.7%. Our results confirmed the fungivory of D. luteipes on P. polysora uredospore. This is the first report of D. luteipes fungivory, which may play an important role in the biological control of P. polysora in corn.

Resumo Relatamos a descoberta de que o predador Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) se alimenta de uredosporos de Puccinia polysora Underw, o agente causal da ferrugem polisora que é uma doença primária que afeta a cultura do milho no Brasil. Realizamos experimentos em laboratório e em casa de vegetação para testar o efeito da fungivoria de D. luteipes (1º/2º e 3º/4º iìstares e adultos) sobre a concentração de uredosporos de P. polysora. Todos os ensaios mostraram uma redução significativa da concentração inicial de uredosporos. Houve uma redução na concentração de uredosporos com o aumento do número de D. luteipes alimentando-se deles. Também testamos o consumo de uredosporos quantificando sua porcentagem nas fezes de D. luteipes. Ninfas do 2º e 4º ínstar, assim como adultos, alimentaram-se de 88%, 85% e 83,8% dos uredosporos, respectivamente. Para ninfas do 3º ínstar, a porcentagem de consumo de uredosporos (75,6%) foi estatisticamente significativo em comparação com os outros grupos. No experimento em casa de vegetação, aos 28 dias após a inoculação das plantas com 9,9 x 104 uredosporos, a porcentagem de consumo de uredosporos foi de 81,7%. Nossos resultados confirmaram a fungivoria de D. luteipes em uredosporos de P. polysora. Este é o primeiro relato de fungivoria de D. luteipes, que pode ter papel importante no controle biológico de P. polysora em milho.

Animals , Zea mays , Brazil , Nymph
Rev. colomb. biotecnol ; 23(2): 47-66, jul.-dic. 2021. tab
Article in Spanish | LILACS | ID: biblio-1360964


RESUMEN El neotrópico es sitio de origen de gran variedad de plantas que actualmente son cultivadas con éxito en diferentes regiones del mundo. Sin embargo, condiciones climáticas adversas, que se pueden ver acrecentadas por efectos del cambio climático antropogénico, pueden afectar su rendimiento y productividad debido a las situaciones de estrés abiótico que se pueden generar. Como alternativa para contrarrestar estos efectos, se ha experimentado con modificaciones genéticas, particularmente en genes relacionados con la producción de osmolitos y factores de transcripción que han llevado a que estas plantas, a nivel experimental, tengan mayor tolerancia a estrés oxidativo, altas y bajas temperaturas y fotoinhibición, sequía y salinidad, mediante la acumulación de osmoprotectores, la regulación en la expresión de genes y cambios en el fenotipo. En este trabajo se presentan y describen las estrategias metodológicas planteadas con estos fines y se complementan con ejemplos de trabajos realizados en cultivos de origen neotropical de importancia económica, como maíz, algodón, papa y tomate. Además, y debido a la novedad y potencial que ofrece la edición génica por medio del sistema CRISPR/Cas9, también se mencionan trabajos realizados en plantas con origen neotropical, enfocados en comprender e implementar mecanismos de tolerancia a sequía. Las metodologías aquí descritas podrían constituirse en opciones prácticas para mejorar la seguridad alimentaria con miras a contrarrestar las consecuencias negativas del cambio climático antropogénico.

ABSTRACT The neotropics are the site of origin of a large variety of plants that are currently successfully cultivated in different regions of the world. However, adverse climatic conditions, which can be exacerbated by the effects of anthropogenic climate change, can affect their yield and productivity due to the abiotic stresses that can be generated. As an alternative to counteract these effects, genetic modifications have been experimentally implemented, particularly in genes related to osmolyte production and transcription factors, which have ultimately led to increased tolerance of these plants to oxidative stress, high and low temperatures and photoinhibition, drought and salinity, through the accumulation of osmoprotectants, regulation of gene expression and changes in phenotype. In this work, the methodological strategies proposed to these aims are presented and described, and they are complemented with examples of studies carried out in economically important crops of neotropical origin, such as corn, cotton, potato and tomato. In addition, and due to the novelty and potential that gene editing offers through the CRISPR/Cas9 system, works conducted in plants with neotropical origin, focused on understanding and implementing drought tolerance mechanisms, are also mentioned. The methodologies described here could become practical options to achieve food security in the frame of the adverse effects caused by anthropogenic climate change.

Gossypium/microbiology , Climate Change , Zea mays
Salud pública Méx ; 63(1): 79-91, Jan.-Feb. 2021. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1395141


Resumen: Objetivo: Evaluar la asociación entre el perfil nutricional y las estrategias de publicidad de alimentos procesados de trigo y maíz (APTM) ofertados en puntos de venta de la Ciudad de México. Material y métodos: Se recolectó información del contenido nutricional y tipos de publicidad para doce categorías de APTM en 58 puntos de venta localizados en zonas de niveles socioeconómicos (NSE) bajo y alto. Resultados: El 8.5 y 10.7% de APTM en NSE bajo y alto fueron saludables, respectivamente. ≤12% de los APTM fueron saludables, excepto harinas (~30%) y pastas (~95%). Entre ambos NSE, de 28.3% a 31.9% de APTM usaron personajes, de 46.5% a 50.1% promociones y de 38.2% a 41.3% claims. Se encontraron asociaciones significativas (p<0.001) en el uso de publicidad de APTM no saludables en ambas zonas de NSE. Conclusiones: La mayoría de los APTM en venta fueron no saludables, y se ofertaron más en el NSE bajo. En ambos NSE la mayoría de APTM no saludables usa estrategias publicitarias para estimular su consumo.

Abstract: Objective: To evaluate the nutrient profile and marketing techniques (MT) of processed wheat and maize foods (PWMF) sold in food retail outlets of Mexico City. Materials and methods: We collected information on nutrient content and MT for PWMF across twelve food categories from 58 retail outlets in high and low income areas of Mexico City. Results: Roughly 8.5% and 10.7% of PWMF, in low and high income areas were healthy, respectively. The ≤12% of PWMF were healthy, except for flours (~33%) and pastas (≥95%). Across both income areas, 28.3%-31.9% of WMPF employed characters, 46.5%-50.1% promotions and 38.2%-41.3% claims. A significant association (p<0.001) was found between the use of MT and unhealthy PWMF in both areas. Conclusion: The majority of PWMF available in the food retail sector were considered unhealthy, which were being more offered in low income areas. Across income areas, the majority of unhealthy WMPF employed MT to encourage consumption.

Biosci. j. (Online) ; 36(6): 1890-1899, 01-11-2020. graf, tab
Article in English | LILACS | ID: biblio-1147953


Maize represents one of the most cultivated crops of cereals in the world, being used as a source of grain, silage and biofuel. Nitrogen is very required in the maize crop, making nitrogen fertilization a significant part of the production cost. The objective of this study was to evaluate the response of two sources of N, urea and coated urea of controlled release, regarding the productivity and the cost/benefit ratio in maize for 2nd harvest. The experiment was carried out in the field in soil classified as dystroferric Red Latosol and treatments distributed in experimental plots, following the randomized block design with four replications. The treatments were 40 kg N ha-1 of common urea; 60 kg N ha-1 of common urea; 40 kg N ha-1 of coated urea; 60 kg of N-coated urea and the control without application of N broadcast application in planting. The maize crop responded to the application of nitrogen at planting. However, the use of coated urea did not increase the grain yield in relation to the use of common urea. The economic analysis demonstrated a better efficiency of use of N and the best net revenues with the application of the dose of 40 kg N ha -1 of common urea in the planting of the crop.

O milho representa uma das culturas de cereais mais cultivadas no mundo, sendo utilizado como fonte de grãos, silagem e biocombustível. O nitrogênio é muito necessário na cultura do milho, tornando a fertilização nitrogenada uma parte significativa do custo de produção. Este trabalho teve como objetivo avaliar o fertilizante nitrogenado revestido de liberação controlada para a cultura do milho de 2ª safra. O trabalho foi desenvolvido na Fazenda Estância Maracaju, localizada no município de Maracaju ­ Mato Grosso do Sul. As parcelas experimentais foram constituídas por 48 linhas com espaçamento de 0,5 metros por 1000 metros de comprimento entre si. Como área útil considerou-se as 30 linhas centrais (1,5 ha). Os tratamentos utilizados foram T1: 40 kg ha-1 de N de ureia comum; T2: 60 kg ha-1 de N de ureia comum; T3: 40 kg ha-1 de N de ureia revestida; T4: 60 kg de N de ureia revestida e T5: sem aplicação de N. Os tratamentos foram distribuídos nas unidades experimentais segundo delineamento de blocos ao acaso com quatro repetições. A cultura de milho, respondeu aplicação de nitrogênio no plantio. O uso de ureia revestida não influenciou na produtividade de grãos em relação a ureia comum no milho de 2ª safra. A melhor eficiência de uso de N e a melhor receita líquida é com a dose de 40 kg de N ureia ha-1, de ureia comum aplicado no plantio da cultura.

Zea mays , Nitrogen
J Genet ; 2020 Nov; 99: 1-5
Article | IMSEAR | ID: sea-215495


Fusarium stalk rot disease (FSR) of maize caused by Fusarium verticillioides (Sacc.) Nirenberg is becoming an important biotic production constraint in many of the major maize growing areas causing substantial yield losses. Inbreds are preferred as parents in hybrid development owing to homozygous nature and high heterotic ability. Double haploid (DH) technology has emerged as a significant milestone. A total of 339 DH lines were generated from two inbred lines, VL1043 (susceptible) and CM212 (resistant), through in vivo haploid induction method. The 339 DH lines along with parents were phenotyped for their response to the FSR at the College of Agriculture, V. C. Farm, Mandya, India during summer, kharif and rabi seasons of the 2019–2020. Best linear unbiased predictors (BLUPs) were estimated for the FSR disease scores over three seasons. A wide range of BLUP scores of three to nine indicated the presence of higher variation for response of DH lines to FSR disease. The higher estimates of standardized range (1.31) and phenotypic coefficient of variation (19.80) also displayed higher variability. Nine lines were moderately resistant and 188 exhibited moderately susceptible reaction. The distribution of DH lines was positively skewed (1.34) and platykurtic (2.31) which suggested complementary epistasis and involvement of large number of genes in the disease expression.

Rev. colomb. cienc. pecu ; 33(2): 121-133, Apr.-June 2020. tab
Article in English | LILACS-Express | LILACS | ID: biblio-1289289


Abstract Background: Rehydration of grains, such as corn and sorghum, is used to increase nutrient absorption. However, the effect of this practice on meat quality is poorly understood. Objective: To evaluate the effects of type of grain and processing on the meat quality of Nellore steers in a feedlot. Methods: Twenty-four non-castrated Nellore steers (270 ± 53 kg initial body weight) were distributed in a completely randomized 2×2 factorial design, with six replicates. The first factor was cereal type (corn or sorghum), and the second was the grain processing (dry or rehydrated and ensiled). The diets were composed of 30% corn silage and 70% concentrate. Sixty days before the beginning of the experiment, corn and sorghum grains were rehydrated and ensiled. The animals were slaughtered after 140 days of confinement. Meat quality analyses were determined in samples of fresh and aged meat (7 days) from the Longissimus lumborum muscle. Results: no difference between treatments was observed for carcass pH and L* (lightness), a* (redness), and b* (yellowness) values, shear force, thawing and cooking losses, and chemical composition of meat (p>0.05). The b* (yellowness) value of subcutaneous fat was higher in steers fed corn, regardless of grain processing (p=0.03). Sarcomere length was higher in aged meat of steers fed sorghum, regardless of processing method (p=0.01). Conclusions: the grain processing method does not affect beef quality; however, grain type can affect subcutaneous fat color and sarcomere length of aged beef.

Resumen Antecedentes: La rehidratación de granos, tales como maíz y sorgo, se usa para aprovechar mejor sus nutrientes. Sin embargo, es poco conocido el efecto de esta práctica sobre la calidad de la carne. Objetivo: Evaluar los efectos del tipo de cereal y su procesamiento sobre la calidad de carne de toretes Nelore en confinamiento. Métodos: Veinticuatro novillos Nelore enteros con un peso promedio inicial de 270 ± 53 kg, se distribuyeron en un diseño factorial 2×2 completamente aleatorizado (n=6). El primer factor fue el tipo de cereal (maíz o sorgo) y el segundo fue su procesamiento (seco o rehidratado y ensilado). Las dietas estuvieron compuestas por 28,44% de ensilaje de maíz y 71,56% de concentrado. Sesenta días antes de iniciar el experimento, los granos de maíz y sorgo se rehidrataron y ensilaron. Los animales se sacrificaron después de 140 días de confinamiento. La calidad de la carne se determinó en muestras de carne fresca y madurada (7 días) obtenidas del músculo Longissimus lumborum. Resultados: No hubo diferencias entre tratamientos para el pH de las canales, ni para los valores de color (L* "luminosidad", a* "intensidad de rojo" y b* "intensidad de amarillo"), fuerza de corte, composición química, o pérdidas de agua por descongelamiento o cocción (p>0,05). El valor de b* de la grasa subcutánea fue mayor en los novillos alimentados con maíz, independientemente del tipo de procesamiento (p=0,03). La longitud de sarcómero fue más alto en la carne madurada de novillos alimentados con sorgo, sin importar el método de procesamiento (p=0,01). Conclusiones: El método de procesamiento del grano no afecta la calidad de la carne; sin embargo, el tipo de cereal afecta el color de la grasa subcutánea y la longitud del sarcómero de la carne madurada.

Resumo Antecedentes: A reidratação de grãos, como milho e sorgo, tem sido usada para aumentar a utilização de seus nutrientes. Contudo, o efeito dessa prática na qualidade da carne é pouco compreendido. Objetivo: Avaliar os efeitos do tipo de grão de cereais e seu processamento sobre a qualidade da carne de bovinos confinados. Métodos: Vinte e quatro bovinos Nelore não castrados, com peso corporal médio inicial de 270 ± 53 kg foram distribuídos em delineamento inteiramente casualizado, fatorial 2×2, com seis repetições. O primeiro fator foi o tipo de grão de cereal no concentrado (milho ou sorgo), e o segundo foi o processamento destes grãos (seco ou reidratado e ensilado). As dietas foram compostas por 28,44% de silagem de milho e 71,56% de concentrado. Sessenta dias antes do início do experimento, os grãos de milho e sorgo foram reidratados e ensilados. Os animais foram abatidos após 140 dias de confinamento. As análises de qualidade da carne foram determinadas em amostras não maturadas e maturadas (7 dias) obtidas do músculo Longissimus lumborum. Resultados: Não houve diferenças significativas (p>0,05) entre os tratamentos para pH da carcaça e L* (luminosidade), a* (intensidade de vermelho), b* (intensidade de amarelo), força de cisalhamento, perdas por descongelamento, perdas por cocção, perdas totais e composição química da carne. O valor de b* da gordura subcutânea foi maior (p=0,03) em bovinos alimentados com dietas contendo grãos de milho, independentemente do tipo de processamento. O comprimento de sarcômero foi maior na carne maturada de novilhos alimentados com sorgo, independente do método de processamento (p=0,01). Conclusões: O método de processamento dos grãos não afetou a qualidade da carne bovina, no entanto, a cor da gordura subcutânea e o comprimento de sarcômero da carne maturada foram afetados pelo tipo de grão.

Electron. j. biotechnol ; 45: 1-9, May 15, 2020. ilus
Article in English | LILACS | ID: biblio-1177370


BACKGROUND: Maize is one of the most important crops worldwide and has been a target of nuclear-based transformation biotechnology to improve it and satisfy the food demand of the ever-growing global population. However, the maize plastid transformation has not been accomplished due to the recalcitrant condition of the crop. RESULTS: In this study, we constructed two different vectors with homologous recombination sequences from maize (Zea mays var. LPC13) and grass (Bouteloua gracilis var. ex Steud) (pZmcpGFP and pBgcpGFP, respectively). Both vectors were designed to integrate into rrn23S/rrn16S from an inverted repeat region in the chloroplast genome. Moreover, the vector had the mgfp5 gene driven by Prrn, a leader sequence of the atpB gene and a terminator sequence from the rbcL gene. Also, constructs have an hph gene as a selection marker gene driven by Prrn, a leader sequence from rbcL gene and a terminator sequence from the rbcL gene. Explants of maize, tobacco and Escherichia coli cells were transformed with both vectors to evaluate the transitory expression­an exhibition of green and red fluorescent light under epifluorescence microscopy. These results showed that both vectors were expressed; the reporter gene in all three organisms confirmed the capacity of the vectors to express genes in the cell compartments. CONCLUSIONS: This paper is the first report of transient expression of GFP in maize embryos and offers new information for genetically improving recalcitrant crops; it also opens new possibilities for the improvement in maize chloroplast transformation with these vectors.

Tobacco/metabolism , Chloroplasts/genetics , Chloroplasts/metabolism , Zea mays/genetics , Green Fluorescent Proteins/metabolism , Transformation, Genetic , Biotechnology , Polymerase Chain Reaction , Plants, Genetically Modified , Plastids/genetics , Green Fluorescent Proteins/genetics , Escherichia coli , Genome, Chloroplast
Article | IMSEAR | ID: sea-204865


Cereal crops such as maize, wheat, sorghum and pearl millet are important for human consumption due to their nutritional benefits. These cereals play pivotal roles to meet world’s food demand. However, maintenance of food security particularly in the circumstance of changing climate, constantly urges for modification of agro-techniques and one such modification is the incorporation of transplanting technique in these cereals as an alternative under a non-practicable situation of direct sowing. Transplanting is a method of transferring seedlings grown in nursery or others to the field. It has been already found to shorten the crop duration and improve germination, plant stand, seed and seedling quality parameters, growth, yield and economic profitability of these cereals. Besides, research findings are also available stating that transplanting helps these cereals to cope up with vagaries of weather and to exhibit greater radiation and water use efficiencies and suppression of weeds. Outcomes of transplanting are however dependent on various factors like methods of nursery raising, the variety used, mode of planting, age of seedlings etc. In spite of these prospects, transplanting technique is not so popular in these cereals due to poor dissemination, discouraging research findings, pest and disease problems, lack of suitable package of practices etc. Therefore, focuses are to be given in conducting more and more research trials to confirm its location and situation wise efficacy and also in developing and disseminating a suitable package of practices of transplanting accordingly.

Biosci. j. (Online) ; 36(2): 341-352, 01-03-2020. tab, graf
Article in English | LILACS | ID: biblio-1146253


Essential oils have emerged as an alternative to synthetic insecticides in the control of stored grain pests. The toxicity and repellency of the essential oils of four basil cultivars and three basil hybrids and the monoterpenes linalool, citral, and (E)-methyl cinnamate were evaluated in the stored grain pests Callosobruchus maculatus and Sitophillus zeamais. The essential oils of the cultivar Genovese and the hybrid 'Genovese' x 'Maria Bonita' were more toxic to C. maculatus. Conversely, the essential oils of the cultivar Sweet Dani and the hybrid 'Cinnamom' x 'Maria Bonita' were more toxic to S. zeamais. Among the monoterpenes, (E)-methyl cinnamate was the most toxic to both pests, taking 0.14 and 0.34 µ L.mL-1 to kill 50% of the C. maculatus and S. zeamais populations, respectively. All essential oils from cultivars, hybrids, and monoterpenes were repellent to S. zeamais, except for (E)-methyl cinnamate. For C. maculatus, this effect was lower, being citral the most repellent compound. Results demonstrate the insecticidal potential of the essential oil of O. basilicum and its monoterpenes in the control of stored grain pests.

Os óleos essenciais surgem como alternativa aos inseticidas sintéticos no controle das pragas de grãos armazenados. A toxicidade e a repelência dos óleos essenciais de quatro cultivares e três híbridos de manjericão e dos monoterpenos linalol, citral e (E)-cinamato de metila foram avaliadas nas pragas de grãos armazenados Callosobruchus maculatus e Sitophillus zeamais. Os óleos essenciais da cultivar Genovese e do híbrido 'Genovese' x 'Maria Bonita' foram mais tóxicos para C. maculatus. Já para S. zeamais, os óleos essenciais das cultivar Sweet Dani e do híbrido 'Cinnamom' x 'Maria Bonita' apresentaram maior toxicidade. Dentre os monoterpenos, o (E)-cinamato de metila foi o mais tóxico para ambas as pragas. Foram necessários 0,14 e 0,34 µ L.mL-1 para matar 50% da população de C. maculatus e S. zeamais. Todos os óleos essenciais das cultivares, dos híbridos e dos monoterpenos foram repelentes a S. zeamais, com exceção do (E)-cinamato de metila. Já para C. maculatus, este efeito foi reduzido, sendo o citral o composto mais repelente. Nos resultados demonstram o potencial inseticida dos óleos essenciais de O. basilicum e seus monoterpenos para o controle de pragas de grãos armazenados.

Oils, Volatile , Ocimum basilicum , Lamiaceae , Insecticides
J Genet ; 2020 Jan; 99: 1-10
Article | IMSEAR | ID: sea-215562


Shi-related sequence (SRS) proteins are plant-specific transcription factors that play important roles in developmental processes, including regulating hormone biosynthesis, response or signal transduction. However, systematical analysis of the SRS gene family in maize has not yet been conducted. In this study, 11 SRS genes with 13 transcripts were identified and characterized. The characteristics of the gene family were analysed in terms of phylogenetic relationships, chromosome distribution and gene structure. RNA-sequencing data analysis showed that the expression patterns of SRS genes were quite different from each other in maize, indicating their divergence in function. Interestingly, the GRMZM2G077752 gene is highly expressed in senescent leaves. Using further coexpression network analysis, we determined that the module containing GRMZM2G077752 were over-represented by genes related to abscisic acid (ABA) stimulus and carbohydrate metabolic process. This result indicated that GRMZM2G077752 might perceive ABA signal and cause the activation of carbohydrate remobilization during leaf ageing. This study provides valuable information for understanding the functions of the SRS genes in maize.

Ciênc. rural (Online) ; 50(6): e20190779, 2020. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1133266


ABSTRACT: Essential oils are possible alternatives to the use of synthetic pesticides for control of fungal contamination. Ginger (Zingiber officinale) essential oil (GEO) is known for having antifungal and antiaflatoxigenic properties, but its use as a fumigant in situ has not been studied yet. The aim of this study was to evaluate GEO's effects upon Aspergillus flavus as a fumigant agent in stored maize grains. The main compounds reported in GEO were α-zingiberene (23.85%) and geranial (14.16%), characterized by gas chromatography-mass spectrometry and nuclear magnetic resonance. The GEO was used as a fumigant in irradiated maize grains in concentrations ranging from 5 to 50 µg/g and the resulting effects were compared to a synthetic antifungal agent (carbendazim and thiram), an antifungal traditionally used for seed treatment. The antifungal efficacy of GEO against A. flavus has been proven in a dose-dependent manner through in situ (maize grains) test. The GEO inhibited aflatoxin production at concentrations 25 and 50 µg/g and controlled fungal growth. Therefore, GEO can be used as an effective and non-toxic alternative to conventional treatments in stored maize grains for the natural control of A. flavus.

RESUMO: Os óleos essenciais são possíveis alternativas ao uso de praguicidas sintéticos no controle da contaminação por fungos. O óleo essencial de gengibre (Zingiber officinale - OEG) é conhecido por possuir propriedades antifúngicas e antiaflatoxigênicas, mas seu uso como fumigante in situ ainda não foi estudado. O objetivo deste estudo foi avaliar os efeitos do OEG sobre Aspergillus flavus como agente fumigante em grãos de milho armazenados. Os principais compostos encontrados no OEG foram α-zingibereno (23,85%) e geranial (14,16%), caracterizados por cromatografia gasosa acoplada a espectrometria de massas e ressonância magnética nuclear. O OEG foi utilizado como fumigante em grãos de milho irradiados em concentrações variando de 5 a 50 µg/g e os efeitos resultantes foram comparados a um agente antifúngico sintético (carbendazim e tiram), antifúngico tradicionalmente usado para o tratamento de sementes. A eficácia antifúngica do OEG contra A. flavus foi comprovada de maneira dependente da dose através do teste in situ (grãos de milho). O OEG inibiu a produção de aflatoxina nas concentrações 25 e 50 µg/g e controlou o crescimento de fungos. Portanto, o OEG pode ser usado como uma alternativa eficaz e não tóxica aos tratamentos convencionais em grãos de milho armazenados para o controle natural de A. flavus.

Braz. arch. biol. technol ; 63: e20200072, 2020. tab, graf
Article in English | LILACS | ID: biblio-1142498


Abstract The response of two local maize (Zea mays L.) genotypes designated as Sahwal-2002 (salt-tolerant) and Sadaf (salt-sensitive) to salt stress was investigated under controlled growth conditions. The role of phenylalanine and seed priming under salt stress in maize with different morphological parameters were studied. The genotype Sadaf, being salt-tolerant, experienced more oxidative damage than the Sahiwall-2002 genotype under salt stress. The salinity affected both growth and physiological attributes of the maize species whereas the phenylalanine successfully increased the salinity tolerance in maize species at the seedling stage.

Soil/chemistry , Zea mays/growth & development , Salinity , Salt Stress , Phenylalanine/analysis , Analysis of Variance , Zea mays/genetics , Genotype
CienciaUAT ; 14(1): 6-17, jul.-dic. 2019. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1124367


Resumen La diversidad del maíz en México se fundamenta por la presencia de 59 a 64 razas; Tamaulipas como estado productor contribuye a mantener la variabilidad entre razas, especialmente en las regiones aisladas. La reserva de la Biósfera "El Cielo" localizada en una región montañosa, que comprende los municipios de Jaumave, Ocampo, Gómez Farías y Llera de Canales, ha sido escasamente estudiada, a pesar de que existen riesgos de degradación o extinción de poblaciones nativas de maíz, por factores como cambios de uso de suelo y fenómenos naturales. El objetivo de este trabajo fue analizar la diversidad morfológica de poblaciones nativas de maíz de la Reserva de la Biósfera "El Cielo". Durante los meses de febrero, marzo y abril del 2016, se realizaron recolectas de maíces nativos en los municipios que comprenden la reserva. El tamaño de la muestra varió, entre 20 y 30 mazorcas de cada población, y de estas, se eligieron 10 mazorcas para registrar variables cuantitativas y cualitativas. Se utilizaron los métodos multivariados de análisis de componentes principales y conglomerados. El 62.45 % correspondió a la variación total, la cual fue explicada por los dos primeros componentes principales, y las variables con mayor contribución a la variación fueron longitud de mazorca, número de granos por hilera, peso de mazorca, peso y volumen de 100 granos, diámetro de mazorca y de olote, número de hileras por mazorca y la relación diámetro/longitud de mazorca. En las poblaciones nativas de maíz que aún se cultivan en la Reserva de la Biósfera "El Cielo", se encontró amplia diversidad morfológica de mazorca, así como variación en la combinación de colores de grano y olote, lo que sugiere que las poblaciones nativas representan un amplio potencial como acervo genético y reservorio de genes.

Abstract The diversity of maize in Mexico is based on the presence of breeds that range from 59 to 64 varieties. Tamaulipas is a corn-producing state that contributes to sustain this enormous variation of breeds, especially in isolated regions. The biosphere ecological reserve "El Cielo" is located in a mountainous region, which comprises Jaumave, Ocampo, Gómez Farías and Llera de Canales municipalities. This region has been scarcely studied in spite of the degrada tion or extinction risks of native populations of maize due to factors such as changes in land use and natural phenomena. The objective of this work was to analyze the morphologic diversity of native maize varieties of "El Cielo" biosphere ecological reserve. Native maize harvests were collected in the municipalities that comprise the reserve during the months of February, March and April of 2016. The sample size ranged between 20 and 30 cobs of each variety, out of this sample 10 cobs were selected in order to register quantitative and qualitative variables. A multivariate analysis method of main components and conglomerates was used. Results show that 62.45 % of the samples were correspondent with total variation, which was explained by the first two main compo nents. The variables with greater contribution to the variation were cob length, number of grains per row, cob weight, weight and volume of 100 grains, cob diameter, number of rows per hob and the relation of diameter/length in each cob. The native maize populations that are still cultivated at the biosphere ecological reserve "El Cielo" there was a wide morphological diversity of cob, as well as variation in the com bination of grain and corncob color. This sug gests that native populations possess a substantial potential as a gene pool and gene reservoir.

Braz. j. biol ; 79(4): 584-588, Nov. 2019. tab
Article in English | LILACS | ID: biblio-1001478


Abstract The properties of maize pollen in the diet of Doru luteipes were determined by biological responses of the predator feeding on natural preys and artificial diet. The biological parameters of D. luteipes fed on Spodoptera frugiperda (Smith, 1797) eggs, maize pollen, Rhopalosiphum maidis (Fitch, 1856) + maize pollen and R. maidis were assessed. The effect of pollen on artificial diet on the biological variables of the predator nymphs and adults were also evaluated. Time span of nymphal development was greater for D. luteipes exclusively fed on earwigs, with the lowest rate of nymph survival. However, maize pollen plus earwigs in the diet provided the predator´s highest survival rate, whilst percentage of fertile females was double when fed on diets composed of S. frugiperda and R. maidis eggs. Development period decreased when D. luteipes nymphs consumed artificial diet plus pollen but there were high fecundity rates (number of laying/female and total egg/female) and a greater percentage of fertile females when they were fed on maize pollen.

Resumo Os benefícios do pólen de milho na composição da dieta de Doru luteipes foram determinados por meio das respostas biológicas desse predador alimentado com presas naturais e dieta artificial. Inicialmente, avaliaram-se parâmetros biológicos de D. luteipes alimentados com: ovos de Spodoptera frugiperda (Smith, 1797), pólen de milho, pólen de milho e Rhopalosiphum maidis (Fitch, 1856) e R. maidis. Posteriormente, verificou-se o efeito da presença do pólen em dieta artificial nas variáveis ​​biológicas de ninfas e adultos do predador. O período de desenvolvimento ninfal foi maior para D. luteipes alimentado, exclusivamente, com pulgões, sendo esta dieta a que propiciou menor sobrevivência ninfal. No entanto, a adição de pólen de milho na dieta com pulgões proporcionou maior taxa de sobrevivência do predador e, o percentual de fêmeas que ovipositaram foi praticamente o dobro em relação às dietas compostas por ovos de S. frugiperda e R. maidis. Quando ninfas de D. luteipes consumiram a dieta artificial adicionada com pólen verificou-se redução no período de desenvolvimento ninfal e quando o pólen de milho foi fornecido apenas na fase adulta houve uma maior fecundidade (número de posturas/fêmea e total de ovos/fêmea) e porcentagem de fêmeas que ovipositaram.

Animals , Female , Pollen , Zea mays , Food Chain , Insecta/physiology , Brazil , Diet , Insecta/growth & development , Nymph/growth & development , Nymph/physiology
Article | IMSEAR | ID: sea-200751


This study, initiated in Côte d'Ivoire, aimed to evaluate the effectiveness of the triple bagging system associated or not with biopesticides on the conservation of biochemical parameters, in particular its nutritional potential according to a central composite design (CCD). It was carried in Côte d'Ivoire at Laboratory of Biochemistry and Food Science from March 2016 to September 2017. Shelf life, biopesticides rate and interactions between shelf life and biopesticides had a significant influence on the biochemical characteristics of maize. The polypropylene bag (control) had the highest values after eighteen (18) months of moisture storage (9.02% to 16.99%) and showed very high fibre losses (P<0.001) (5.78% to 4.28%), total sugars (2.62% to 1.30%), reducing sugars (0.47% to 0.27%), starch (75.20% to 46.10%), fat (5.51% to 3.33%), protein (8.60% to 6.87%), total carbohydrate (75.20% to 71.51%), ash (1.68% to 1.30%) and energy value (384.78% to 343.48%). Concerning the triple bagging system without biopesticides, the variation is similar to the treatments that received the biopesticides up to 9.5 months of storage before presenting values almost similar to the control bag after the 18 months of storage. While triple bagging systems with the presence of biopesticides after 18 months of storage show slight variations in moisture (9.02% to 12.47%), fibre (5.78% to 5.56%), total sugars (2.62% to 1,88%), reducing sugars (0.47% to 0.37%), starch (75.20% to 60.03%), fat (5.51% to 5.00%), protein (8.60% to 7.84%), total carbohydrates (75.20% to 72.69%), ash (1.68% to 1.50%) and energy value (384.78% to 368.93%). The results of these tests show that maize grains stored in the presence of biopesticides best retain their biochemical characteristics. Also, the results indicate that the rate of 1.01% biopesticides could be recommended for maintaining all biochemical parameters up to 18 months of storage.

Article | IMSEAR | ID: sea-189700


The environmental risk assessment of the insect resistant genetically modified maize MON 89034 (Reference EFSA/GMO/BE/2011/90) has been performed by the Panel on Genetically Modified Organisms (GMO) of the Norwegian Scientific Committee for Food Safety (VKM). VKM has been requested by the Norwegian Directorate for Nature Management and the Norwegian Food Safety Authority to issue a preliminary scientific opinion on the safety of the genetically modified maize MON 89034 (Unique identifier MON-89Ø34-3) for cultivation, and submit relevant scientific comments or questions to EFSA on the application EFSA/GMOBE/2011/90. The current submission is intended to complement application EFSA-GMO-NL-2007-37, which was approved by Commission Decision 2009/813/EC of 30 October 2009, authorising the placing on the market of products containing, consisting of, or produced from genetically modified maize MON 89034 (scope import, processing, food and feed). Maize MON89034 has previously been assessed by the VKM GMO Panel in connection with EFSA´s public hearing of the application EFSA/GMO/NL/2007/37 (VKM 2008a). Preliminary health- and environmental risk assessments of several stacked events, with MON 89034 as one of the parental lines, have also been performed by the VKM GMO Panel (VKM 2009a, b, c; VKM 2010a,b). The environmental risk assessment of the maize MON 89034 is based on information provided by the applicant in the application EFSA/GMO/BE/2011/90, and scientific comments from EFSA and other member states made available on the EFSA website GMO Extranet. The risk assessment also considered peer-reviewed scientific literature as relevant. The VKM GMO Panel has evaluated MON 89034 with reference to its intended uses in the European Economic Area (EEA), and according to the principles described in the Norwegian Food Act, the Norwegian Gene Technology Act and regulations relating to impact assessment pursuant to the Gene Technology Act, Directive 2001/18/EC on the deliberate release into the environment of genetically modified organisms, and Regulation (EC) No 1829/2003 on genetically modified food and feed. The Norwegian Scientific Committee for Food Safety has also decided to take account of the appropriate principles described in the EFSA guidelines for the risk assessment of GM plants and derived food and feed (EFSA 2006, 2011a), the environmental risk assessment of GM plants (EFSA 2010), the selection of comparators for the risk assessment of GM plants (EFSA 2011b), and for the post-market environmental monitoring of GM plants (EFSA 2006, 2011c). The scientific risk assessment of maize MON 89034 include molecular characterisation of the inserted DNA and expression of target proteins, comparative assessment of agronomic and phenotypic characteristics, unintended effects on plant fitness, potential for gene transfer, interactions between the GM plant and target and non-target organisms, effects on biogeochemical processes and evaluations of the post-market environmental plan. In line with its mandate, VKM emphasised that assessments of sustainable development, societal utility and ethical considerations, according to the Norwegian Gene Technology Act and Regulations relating to impact assessment pursuant to the Gene Technology Act, shall not be carried out by the Panel on Genetically Modified Organisms. The genetically modified maize MON 89034 was developed to provide protection against certain lepidopteran target pest, including European corn borer (Ostrinia nubilalis) and Mediterranean corn borer (Sesamia nonagrioides). Protection is achieved through expression in the plant of two insecticidal Cry proteins, Cry1A.105 and Cry2Ab2, derived from Bacillus thuringiensis, a common soil bacterium. Cry1A.105, encoded by the cry1A.105 gene, is a chimeric protein made up of different functional domains derived from three wild-type Cry proteins from B. thuringiensis subspecies kurstaki and aizawai. The Cry2Ab2 protein is encoded by the cry2Ab2 gene derived from B. thuringiensis subspecies kurstaki. Molecular characterization: Appropriate analysis of the integration site, including flanking sequence and bioinformatics analysis, has been performed to characterise the transformation event MON 89034. The results of the segregation analysis are consistent with a single site of insertion for the cry1A.105 and cry2Ab2 gene expression cassettes and confirm the results of the molecular characterisation. Molecular analysis of both self-pollinated and cross-fertilised lines, representing a total of seven different generations, indicates that the inserted DNA is stably transformed and inherited from one generation to the next. No genes that encode resistance to antibiotics are present in the genome of MON 89034 maize. The molecular characterisation confirmed the absence of both the aad and nptII genes, which were used in the cloning and transformation process. Event MON 89034 and the physical, chemical and functional characteristics of the proteins have previously been evaluated by The VKM Panel on Genetically Modified Organisms, and considered satisfactory (VKM 2008a). Comparative assessment: The field trials for comparative assessment of agronomic and phenotypic characteristics of maize MON 89034 in the USA (2004-2005) and Europe (2007), have been performed in accordance with the EFSAs guidelines for risk assessment of genetically modified plants and derived food and feed (EFSA 2010, 2011a). Based on results from the comparative analyses, it is concluded that maize MON 89034 is agronomically and phenotypically equivalent to the conventional counterpart and commercial available reference varieties, with the exception of the lepidopteran-protection trait. The field evaluations support a conclusion of no phenotypic changes indicative of increased plant weed/pest potential of MON 89034 compared to conventional maize. Evaluations of ecological interactions between maize MON 89034 and the biotic and abiotic environment indicate no unintended effects of the introduced trait on agronomic and phenotypic characteristics. Environmental risk: There are no reports of the target Lepidopteran species attaining pest status on maize in Norway. Since there are no Bt-based insecticides approved for use in Norway, and lepidopteran pests have not been registered in maize, issues related to resistance evolution in target pests are not relevant at present for Norwegian agriculture. Published scientific studies show no or negligible adverse effects of Cry1A.105 and Cry2Ab2 proteins on non-target arthropods that live on or in the vicinity of maize plants. Cultivation of maize MON 89034 is not considered to represent a threat to the prevalence of red-listed species in Norway. Few studies have been published examining potential effects of Cry1A.105 and Cry2Ab toxin on ecosystems in soil, mineralization, nutrient turnover and soil communities. Some field studies have indicated that root exudates and decaying plant material containing Cry proteins may affect population size and activity of rhizosphere organisms (soil protozoa and microorganisms). However, data are only available from short term experiments and predictions of potential long term effects are difficult to deduce. Most studies conclude that effects on soil microorganisms and microbial communities are transient and minor compared to effects caused by agronomic and environmental factors. Few studies have assessed the impact of Cry proteins on non-target aquatic arthropods and the fate of these proteins in senescent and decaying maize detritus in aquatic environments. Further studies with better experimental design are needed for the assessment of the potential effects of Bt crops on aquatic organisms. However, exposure of non-target organisms to Cry proteins in aquatic ecosystems is likely to be very low, and potential exposure of Bt toxins to non-target organisms in stream ecosystems in Norway is considered to be negligible. Maize is the only representative of the genus Zea in Europe, and there are no cross-compatible wild or weedy relatives outside cultivation with which maize can hybridise and form backcross progeny. Vertical gene transfer in maize therefore depends on cross-pollination with other conventional or organic maize varieties. In addition, unintended admixture of genetically modified material in seeds represents a possible way for gene flow between different crop cultivations. The risk of pollen flow from maize volunteers is negligible under Norwegian growing conditions. In addition to the data presented by the applicant, the VKM GMO Panel is not aware of any scientific report of increased establishment and spread of maize MON 89034 and any change in survival (including over-wintering), persistence and invasiveness capacity. Because the general characteristics of maize MON 89034 are unchanged, insect resistance are not likely to provide a selective advantage outside cultivation in Norway. Since MON 89034 has no altered agronomic and phenotypic characteristics, except for the specific target pest resistance, the VKM GMO Panel is of the opinion that the likelihood of unintended environmental effects due to the establishment and survival of maize MON 89034 will be no different to that of conventional maize varieties in Norway The environmental risk assessment will be completed and finalized by the VKM Panel on Genetically Modified Organisms when requested additional information from the applicant is available.