Diversity of culturable endophytic fungi vary through time in Manihot esculenta Crantz / A diversidade de fungos endofíticos cultiváveis ​​varia ao longo do tempo em Manihot esculenta Crantz

Abstract Endophytic fungi are a ubiquituos group that colonize all plant species on earth. Studies comparing the location of endophytic fungi within the leaves and the sampling time in Manihot esculenta Crantz (cassava) are limited. In this study, mature leaves of M. esculenta from Panama were collected in order to compare the cultivable diversity of endophytic fungi and to determine their distribution within the leaves. A total of one hundred sixty endophytes belonging to 97 species representing 13 genera and 8 morphospecies determined as mycelia sterilia that containing 63 isolates were isolated. Cladosporium, Nigrospora, Periconia, and mycelia sterilia 1 and 3 were the most predominant isolated endophytes. We detected that endophytes varied across the sampling time, but not amongst locations within leaves. The endophytes composition across sampling and the location of endophytes within leaf was similar, except for Periconia and mycelia sterilia 3 and 7. The data generated in this study contribute to the knowledge on the biodiversity of endophytic fungi in Panama, and establish the bases for future research focused on understanding the function of endophytes in M. esculenta crops.

Resumo Os fungos endofíticos são um grupo ubiquituo que colonizam todas as espécies de plantas na terra. Os estudos que comparam a localização dos fungos endofíticos dentro das folhas de Manihot esculenta Crantz (mandioca) e o tempo de amostragem são muito escassos. Neste estudo, folhas maduras de M. esculenta foram coletadas do Panamá com a finalidade de comparar a diversidade cultivável de endófitos e determinar sua distribuição dentro das folhas. Um total de 170 endófitos foram isolados de 97 espécies que representam 13 gêneros e 8 morfoespécies determinadas como micélios esterilizados contendo 63 isolados. Os fungos Cladosporium, Nigrospora, Periconia e mycelia sterilia 1 e 3 foram os isolados mais predominantes. Também detectamos que os endófitos variaram ao longo do tempo de amostragem, mas não entre os locais dentro das folhas. A composição de endófitos na amostragem e localização de endófitos dentro da folha foi semelhante, exceto para Periconia e mycelia sterilia 3 e 7. Os dados gerados neste estudo contribuem para o conhecimento da biodiversidade de fungos endofíticos no Panamá e estabelecem as bases para pesquisas sobre o entendimento da função de endófitos em culturas de M. esculenta.

Diversity of culturable endophytic fungi vary through time in Manihot esculenta Crantz

Abstract Endophytic fungi are a ubiquituos group that colonize all plant species on earth. Studies comparing the location of endophytic fungi within the leaves and the sampling time in Manihot esculenta Crantz (cassava) are limited. In this study, mature leaves of M. esculenta from Panama were collected in order to compare the cultivable diversity of endophytic fungi and to determine their distribution within the leaves. A total of one hundred sixty endophytes belonging to 97 species representing 13 genera and 8 morphospecies determined as mycelia sterilia that containing 63 isolates were isolated. Cladosporium, Nigrospora, Periconia, and mycelia sterilia 1 and 3 were the most predominant isolated endophytes. We detected that endophytes varied across the sampling time, but not amongst locations within leaves. The endophytes composition across sampling and the location of endophytes within leaf was similar, except for Periconia and mycelia sterilia 3 and 7. The data generated in this study contribute to the knowledge on the biodiversity of endophytic fungi in Panama, and establish the bases for future research focused on understanding the function of endophytes in M. esculenta crops.

Resumo Os fungos endofíticos são um grupo ubiquituo que colonizam todas as espécies de plantas na terra. Os estudos que comparam a localização dos fungos endofíticos dentro das folhas de Manihot esculenta Crantz (mandioca) e o tempo de amostragem são muito escassos. Neste estudo, folhas maduras de M. esculenta foram coletadas do Panamá com a finalidade de comparar a diversidade cultivável de endófitos e determinar sua distribuição dentro das folhas. Um total de 170 endófitos foram isolados de 97 espécies que representam 13 gêneros e 8 morfoespécies determinadas como micélios esterilizados contendo 63 isolados. Os fungos Cladosporium, Nigrospora, Periconia e mycelia sterilia 1 e 3 foram os isolados mais predominantes. Também detectamos que os endófitos variaram ao longo do tempo de amostragem, mas não entre os locais dentro das folhas. A composição de endófitos na amostragem e localização de endófitos dentro da folha foi semelhante, exceto para Periconia e mycelia sterilia 3 e 7. Os dados gerados neste estudo contribuem para o conhecimento da biodiversidade de fungos endofíticos no Panamá e estabelecem as bases para pesquisas sobre o entendimento da função de endófitos em culturas de M. esculenta.

Reduction of Microbial Contamination of Chechin nchabe (Cooked Fermented Cassava) Produced in Noun (West Cameroon) by a Second Fermentation

The Chechim nchabe is a traditional food widely consumed in Foumban, Foumbot, Koutaba, Massangam, Kouoptamo, Malentouen and Magba, 07 Departments of Noun (West region of Cameroon). It is obtained by fermenting cassava sticks cooked on the surface of river or spring water. Unfortunately, the bad hygienic quality of the environment during production promotes its contamination by pathogenic germs. The objective of this study is to carry out a second fermentation in order to reduce contamination of Chechim nchabe by pathogens germs during production. To achieve this objective, a survey on the socio-economic data, profile of the producers, production protocol and characteristics of product have been realized. After microbiological analysis of Chechim nchabe, a second fermentation was performed in the laboratory. From the results, it appears that all the producers are women, aged between 51 and 58 years and 87% of them not attending school. The water used for soaking the cassava revealed that 54% of women use river water and 46% spring water. The Chechim nchabe samples collected after traditional production in the 07 Departments of Noun, show average contamination of Enterobacteriaceae, moulds, staphylococci, Escherichia coli and lactic acid bacteria with respective concentrations of 4.7; 4.1; 4.4; 4.7 and 4.8 Log10ufc/mL. However, Chechim nchabe produced in urban areas such as Foumbot and Foumban recorded low contamination compared to that produced in rural areas like Massangam, which were heavily contaminated with Escherichia coli and Enterobacteriaceae. It was also noted that the Chechim nchabe produced in spring water is more contaminated than that produced in river water. The second fermentation for 10 hours of Chechim nchabe in a basin, after 12 hours of traditional fermentation, eliminated all of pathogenic germs from Chechim nchabe. This second fermentation of 10 hours could be a solution to guarantee the sanitary quality of Chechim nchabe before its consumption.

Screening for neurocognitive deficits in adult populations reliant on toxic cassava as the main source of food

Context and objective. Chronic dietary reliance on improperly processed cyanogenic toxic cassava is widespread in sub-Saharan Africa. The objective of the present study was to screen for neurocognition impairments and daily-life functioning in adults with dietary dependency on cyanogenic cassava as the main source of food. Methods. A cross-sectional design enrolled heads of households (in couples) in the rural district of Kahemba, Democratic Republic of Congo. Participants were screened for neurocognitive impairments using the Community Screening Interview for Dementia (CSID). Detailed neuropsychiatric evaluations were performed and disease entities classified according to the Diagnostic and Statistical Manual of Mental Disorders (DSM IV) criteria when applicable. Cassava cyanogenic exposure was ascertained by urinary concentrations of thiocyanate (SCN). Regression models were used to identify predictors of CSID performance at the 0.05 significance level. Results. For hundred and six households (203 couples, mean age 38.4 ± 11. 4 years) were involved. One hundred thirty-six subjects (33.5 %) [69 women and 67 men, mean age 39 ± 14.4 years)] and 13 (3.2 %) [7 women and 6 men, mean age: 32 ± 2.6 years] fulfilled the criteria for mild cognitive impairment (MCI) and Major Neurocognitive disorder (MNCD), respectively. The overall mean urinary concentration of SCN was 949.5+518.3 mol/l after adjusting Context and objective. Chronic dietary reliance on improperly processed cyanogenic toxic cassava is widespread in sub-Saharan Africa. The objective of the present study was to screen for neurocognition impairments and daily-life functioning in adults with dietary dependency on cyanogenic cassava as the main source of food. Methods. A cross-sectional design enrolled heads of households (in couples) in the rural district of Kahemba, Democratic Republic of Congo. Participants were screened for neurocognitive impairments using the Community Screening Interview for Dementia (CSID). Detailed neuropsychiatric evaluations were performed, and disease entities classified according to the Diagnostic and Statistical Manual of Mental Disorders (DSM IV) criteria when applicable. Cassava cyanogenic exposure was ascertained by urinary concentrations of thiocyanate (SCN). Regression models were used to identify predictors of CSID performance at the 0.05 significance level. Results. For hundred and six households (203 couples, mean age 38.4 ± 11. 4 years) were involved. One hundred thirty-six subjects (33.5 %) [69 women and 67 men, mean age 39 ± 14.4 years)] and 13 (3.2 %) [7 women and 6 men, mean age: 32 ± 2.6 years] fulfilled the criteria for mild cognitive impairment (MCI) and Major Neurocognitive disorder (MNCD), respectively. The overall mean urinary concentration of SCN was . for age, gender, nutritional status, and history of konzo, neurocognition domain-specific deficits were independently associated with either hypertension or USCN (350mol / l incremental increase in excretion Functional impairments in daily-life activities increased as subjects poorly performed at the CSID screening (Spearman r = - .2, p < 0.01). Conclusion. Neurocognitive deficits in adults are common in Congolese adults relying on cyanogenic cassava as the main source of food. Our study findings warrant further studies to elucidate the overall lifespan brain/behavioral burden and mechanisms of cassava toxicity among adults with dietary dependency on cyanogenic cassava as the main source of food

Peligros microbiológicos relacionados con alimentos fermentados de elaboración artesanal comercializados en Tunja, Nariño y Cauca / Microbiological risks related to artisanal fermented foods marketed in Tunja, Nariño and Cauca

RESUMEN Varios factores intervienen en la calidad de los alimentos, como los físicos, químicos, nutricionales, sensoriales y microbiológicos. Este último es importante, ya que, afecta las propiedades organolépticas del producto terminado y, además, puede ocasionar riesgos de salud pública asociados a peligros microbiológicos. Colombia es un país rico en gastronomía, incluyendo alimentos fermentados de elaboración artesanal (AFEA), los cuales son una alternativa actual para sistemas agroalimentarios que buscan alimentos más naturales. El objetivo de este estudio fue evaluar los criterios microbiológicos en AFEA y el cumplimiento de requisitos sanitarios para sensibilizar a productores de bebidas artesanales y revalorizar los productos. Se tomaron en cuenta 11 productores artesanales de Masato, Champús y Almidón agrio de yuca en zonas rurales del país, que voluntariamente aceptaron participar. Se midieron los parámetros de pH, humedad, sólidos solubles y recuentos microbiológicos. Con estos resultados, se pudo calcular el porcentaje de conformidad de los alimentos, de los cuales el 36 % de productos evaluados fueron aptos para el consumo. Se incumplieron los límites establecidos para Escherichia coli, Staphylococcus aureus, Bacillus cereus y Salmonella sp. Los análisis fisicoquímicos mostraron que el Masato y el Champús aportan condiciones abióticas para el crecimiento microbiano. Además, los productores Almidón agrio de yuca tuvieron mayor valoración en el cumplimiento de requisitos sanitarios y menor cumplimiento que los productores de Champús. Los análisis realizados indican que la mayoría de los alimentos incumplieron los límites permitidos por lo cual se debe capacitar a los productores en buenas prácticas de manufactura.

ABSTRACT Several factors intervene in the quality of the food, such as physical, chemical, nutritional, sensory, and microbiological. The latter is important as it affects the sensory properties of the finished product, and it can also cause public health risks associated with microbiological hazards. Colombia is a country rich in gastronomy, including artisanal fermented foods (AFEA), which are a current alternative for agri-food systems seeking for more natural foods. The objective of this study was to evaluate the microbiological criteria in AFEA and its compliance with the sanitary requirements to raise the awareness among crafted beverages producers and revalue the products. Eleven artisan producers of masato, champús and sour cassava starch in rural areas of the country, who voluntarily agreed to participate, were considered. The parameters of pH, humidity, soluble solids, and microbiological counts were measured. With these results, it was possible to calculate the compliance rate of the food, from which 36% of the products evaluated were fit for consumption. The limits established for Escherichia coli, Staphylococcus aureus, Bacillus cereus and Salmonella spp were breached. Physicochemical analysis showed that Masato and Champús provide abiotic conditions for microbial growth. In addition, the Sour cassava starch producers had higher compliance ratings regarding sanitary requirements but lower compliance ratings than champús producers. The performed analysis indicates that most of the food did not comply with the permitted limits, which is why producers must be trained in good manufacturing practices.

Potentials of Cassava, Bambara Groundnut and Tigernut in Biscuit Production: A Review

Due to varying changes in lifestyle, economic level and urbanization in the developing countries, the consumption of biscuit and the development of food products using composite flour have increased and are attracting much attention from researchers in bakery and pastry productions. This work reviewed the potentials of cassava, bambara groundnut and tigernut composite flours in biscuit production. This study also includes studies on the use of flours from other tubers, legumes, cereals, and fruit sources in place of wheat flour to make a variety of food products in varying amounts. It was revealed that flour made from cassava, bambara groundnut and tigernut used to produce biscuit products has the capacity of maintaining similar characteristics to products made from full-wheat flour. The finished result demonstrates the cumulative impact of this option in terms of its functional and physicochemical features, as well as the health advantages of raw mixed flour and percentage blending. In addition, composite flour is an excellent new strategy for employing unusual food products becaue its use produced goods with a range of qualities and features, depending on the types and proportions of wheat flour used in the formulation. Also this review stated some possible challenges likely to be encountered in case Nigeria changes from use of wheat flour to composite flours and blends of non-wheat flours.

Nitrogen-Fixing and Phosphate Solubilizing Potentials of Rhizobacteria from the Rhizosphere of Two Cassava Varieties in Iyamho Community

Microorganisms in close association with the roots of plants can enhance plant growth, through nitrogen fixation (NF) and phosphorus solubilization (PS). Although the type of microbes in close association with different plants varies, their population and genetic capabilities is affected by several factors. Therefore, in this study, the plant growth promoting properties of rhizobacteria present in the rhizosphere of two cassava varieties (Sweet cassava US, bitter cassava ST) indigenous to Iyamho community was explored. The samples were analyzed for total culturable heterotrophic bacteria community and the obtained isolates were screened for NF and PS abilities using a semi-solid N-free medium and Pikovaskya agar respectively. The bacterial population in both agar medium varied, however, the bacterial counts on Luria Bertani (3.67 x 105, 3.35 x 106) was higher than Nutrient agar (2.73 x 105, 2.68 x 105) after incubation for 24 hours at 37oC for sweet and bitter cassava rhizosp here respectively. Also, isolates from sweet cassava had the highest bacteria count in both Nutrient agar and Luria Bertani agar. A total of sixteen isolates were obtained, six phosphate solubilizers, five nitrogen fixers, and five without traits for either NF or PS. The Gram-negative bacterial group was more dominant across all isolates while the dominant genus was Bacillus. This study indicates that the nitrogen fixers and phosphate solubilizers are major constituents of the rhizomicrobe of cassava plants although the distribution varies across cassava varieties. However, sweet cassava rhizosphere harbored more nitrogen-fixing bacteria while both varieties had the same amount of phosphate solubilizing rhizobacteria.

Isolation, Identification and Mode of action of Partially Purified Bacteriocins from Lactic Acid Bacteria in Fermented Cassava Grits

The study on the isolation, identification and mode of action of partially purified bacteriocin from lactic acid bacteria found in fermented cassava grits was carried out. Fermented cassava grits were collected from different garri processing plants and transported with cold box to the laboratory for analysis. The viable microbial count after the partially purified bacteriocin from the various lactic acid bacteria isolates were grown against the food borne bacteria (Staphylococcus aureus and Bacillus subtilis) ranged from 0.98 x 103 CFU/ml for partially purified bacteriocin from isolate 6 at 8 hrs to 9.2 x103 CFU/ml for isolate 3 at 24 hrs. Similar results were obtained against Bacillus subtilis with microbial counts that ranged from 1.02 x102 CFU/ml for isolate 3 at 8 hrs to 9.2 x 102 CFU/ml at 24 hrs. Isolates 6, 7, 10 and 11 were bactericidal to both Staphylococcus aureus and Bacillus subtilis while isolate 3 was bacteriostatic. The viable microbial count after the partially purified bacteriocin was grown against the foodborne bacteria (Escherichia coli and Salmonella typhi) ranged from 1.0 x102 CFU/ml for partially purified bacteriocin from isolate 3 at 8 hrs to 7.1 x 102 CFU/ml for partially purified bacteriocin from isolate 6 at 24 hours. The microbial count against Salmonella typhi ranged from 6.50 x 102 CFU/ml for isolate 6 at 8 hrs to 8.5 x 102 CFU/ml for isolate 7 at 24 hrs. Partially purified bacteriocins from isolates 3 and 7 were bacteriostatic while isolates 6, 10 and 11 were bactericidal to Escherichia coli and Salmonella typhi. This result showed that the partially purified bacteriocins were very efficacious in killing or inhibiting the growth of some foodborne pathogens which can be applied in biopreservation.

Biology of Trichogramma marandobai and T. manicobai (Hymenoptera: Trichogrammatidae) in eggs of Erinnyis ello (Lepidoptera: Sphingidae)

ABSTRACT Parasitoids of the genus Trichogramma are promising for the biological control of insect pests in several crops, including cassava, which is severely attacked by Erinnyis ello L., 1758 (Lepidoptera: Sphingidae). Evaluating the biological aspects of these parasitoids to understand their dynamics is an important step towards the implementation of this control strategy in the field. Thus, our objective was to evaluate the biology of Trichogramma manicobai Brun, Moraes & Soares, 1984, and T. marandobai Brun, Moraes & Soares, 1986 in E. ello eggs. The parasitoids were obtained by collecting E. ello eggs from a commercial production of cassava, and the host's eggs were obtained from laboratory and greenhouse rearings. The average duration of a generation (T), net reproduction rate (R0), intrinsic rate of increase (rm), and the finite rate of increase (λ) were estimated, and from these, the fertility life table was calculated. The results indicated that T. marandobai has both higher net reproduction rate and a higher intrinsic rate of increase as well as requires less time to double its population than T. manicobai. Thus, T. marandobai has potential for natural and conservative biological control of E. ello. In addition, its potential in applied biological control should be evaluated through studies on the viability of its mass rearing in alternative hosts and its dispersion behavior in the field.

ARABIDOPSIS MUESTRA RESISTENCIA NO-HOSPEDERO CONSTITUTIVA CONTRA Xanthomonas phaseoli pv. manihotis / Arabidopsis shows non-host constitutive resistance against Xanthomonas phaseoli pv. Manihotis

RESUMEN La bacteriosis vascular de la yuca, causada por la bacteria gram negativa Xanthomonas phaseoli pv. manihotis (Xpm), anteriormente conocida como Xanthomonas axonopodis pv. manihotis, es la principal enfermedad bacteriana que compromete su producción. Con la meta de generar una resistencia durable y de amplio espectro a la bacteriosis es posible explotar los mecanismos naturales presentes en plantas no-hospedero. Arabidopsis es una planta modelo extensamente estudiada, la cual es no-hospedero de Xpm. La meta de este estudio fue determinar si la resistencia no-hospedero de Arabidopsis es consecuencia de la presencia de barreras físicas o si esta depende de determinantes genéticos. En este trabajo se evaluó la capacidad de plantas de Arabidopsis de responder a la inoculación con Xpm. Ninguno de los ocho ecotipos de Arabidopsis evaluados mostraron una respuesta hipersensible a la inoculación con ocho diferentes cepas de Xpm. Aunque no se identificó la presencia de especies reactivas de oxígeno si se encontró un bloqueo en el crecimiento de Xpm en las plantas de Arabidopsis. En conjunto, los resultados aquí presentados sugieren que Arabidopsis no está activando una respuesta contra Xpm y que la resistencia observada puede ser consecuencia de las barreras físicas presentes en Arabidopsis que Xpm no es capaz de superar.

ABSTRACT Cassava bacterial blight (CBB), caused by the gram-negative bacteria Xanthomonas phaseoli pv. manihotis (Xpm), previously known as Xanthomonas axonopodis pv. manihotis, is the main bacterial disease compromising cassava production. With the aim to generate durable and broad-spectrum resistance to CBB is possible to exploit the natural mechanism present in non-host plants. Arabidopsis is an extensively studied model plant, which is a non-host of Xpm. The aim of this study was to determinate if the Arabidopsis non-host resistance is a consequence of physical barriers or if it depends on genetic determinants. In this work we evaluated the ability of Arabidopsis plants to respond after Xpm inoculation. None of the eight Arabidopsis ecotypes showed a hypersensitive response after inoculation with eight different Xpm strains. Although reactive oxygen species (ROS) production was not present, impairment in Xpm proliferation was found. These results suggest that Arabidopsis is not activating an immunity response against Xpm and the resistance might be a consequence of physical barriers present in Arabidopsis that Xpm is not able to overcome.

In vitro multiplication of wild Manihot species with different naphthaleneacetic acid and benzylaminopurine concentrations

In vitro multiplication is an important tissue culture technique that is capable of efficiently producing seedlings at any scale. It is a propagation method based on the aseptic culture of small propagules in a suitable culture medium to enable plant regeneration. Multiplication experiments conducted in vitro to set protocols adapted to wild Manihot species have used modified mineral salts and MS vitamins as basic culture medium. Here, 25 treatments based on combinations of the regulators benzylaminopurine (BAP) and naphthaleneacetic acid (NAA) at 0, 0.025, 0.05, 0.075, and 0.1 mg L-1 were used for in vitro multiplication of three genotypes of wild Manihot species (M. violaceae Pohl Müll. Arg., M. pseudoglaziovii Pax & Hoff., and M. flabellifolia Pohl). Plant height and the number of 1 cm minicuttings, number of roots, shoots, green leaves and senescent leaves were recorded 120 days after explant inoculation. M. violaceae Pohl. Müll. Arg. and M. flabellifolia Pohl. presented favorable results with 0.05 and 0.025 mg L-1 NAA, respectively. Culture medium lacking NAA and BAP favored the in vitro growth of M. pseudoglaziovii Pax & Hoff.

Superoxide Dismutase Expression in the Ovaries of Periodontitis Animal Models Induced by Porphyromonas gingivalis and Treated with Cassava Leaves Extract

@#The ovaries represent the female reproductive organs that determine the women's fertility status and their systemic and oral health, correlating to sex steroid hormone alteration. This study aimed to investigate the effect of cassava leaves extract treatment to SOD expression in the animal model-ovaries after Porphyromonas gingivalis injection. 15 female Sprague Dawley rats were used and divided into five groups: (1) control without cassava leaves extract treatment (C); (2) P. gingivalis without cassava leaves extract treatment (T1); (3) P. gingivalis and cassava leaves extract (T2); (4) P. gingivalis and vitamin C (T3); and (5) P. gingivalis and metronidazole (T4). Animal were euthanised at day seven after the initial treatment to collect ovaries. The ovaries sections were immunohistochemically stained to quantify SOD expression using light microscope while the Image J software was used to quantify the SOD expression. The results showed that all of the follicle types had the same intensity of SOD expression. Most of the follicles exhibited low intensity of SOD expression, except for atretic follicles. In conclusion, P. gingivalis and cassava leaves extract influenced SOD expression in the ovaries of animal models, which increased the SOD expression.

Determination of cyanide in cassava starch by continuous flow online distillation / 公共卫生与预防医学

Objective To explore the determination of cyanide in cassava starch by a continuous flow online distillation method. Methods Cassava starch was extracted with sodium hydroxide solution, filtered and then quantitatively analyzed with a continuous flow analyzer. The effects of extraction concentration, ultrasonic time, sample size and separation method on cyanide determination were investigated. Results 2.0 g samples were directly weighed and added to 100 mL 2 g/L sodium hydroxide solution for ultrasonic extraction for 20 min, and filtered with qualitative filter paper. The filtrate was quantitatively determined with a continuous flow analyzer. The linear relationship between cyanide concentration of 0 mg/L and 0.20 mg/L was good, r ≥ 0.999. The detection limit of the method was 0.01 mg/kg, the limit of quantitation was 0.03 mg/kg, the relative standard deviation was 0.26%-1.52%, and the standard addition recovery rate was 90.36%-104.19%. Conclusion The continuous flow online distillation method has the advantages of low detection limit, good repeatability, automatic operation, reduction of manual errors, and high analysis speed, which is beneficial to improve work efficiency, and can be used for batch detection of cyanide in cassava starch.

Effect of carbohydrate source on productive performance, ruminal and systemic health of grazing cows / Efecto de la fuente de carbohidratos sobre el desempeño productivo, la salud ruminal y sistémica de vacas en pastoreo / Efeito da fonte de carboidratos sobre o desempenho produtivo, saúde ruminal e sistêmica de vacas em pastejo

Abstract Background: The nutritional limitations of Cenchrus clandestinus -i.e., high protein and low energy concentrations- make it necessary to supplement cows with non-fibrous carbohydrate (NFC) sources to improve productive performance. Nevertheless, such supplementation can lead to ruminal acidosis. Objective: To evaluate partial replacement of corn grain (Zea mays, ZM) with sorghum grain (Sorghum vulgare, SV), cassava root (Manihot esculenta, MES) or citrus pulp (Citrus sp., C) on milk yield and quality, ruminal pH and health of grazing cows. Methods: Eight Holstein cows were evaluated in a 4 x 4 Latin square design during the first 60 days of lactation. Treatments (isoenergetic rations, 1.45 ± 0.003 Mcal NEL/kg DM) consisted of a mixture of grass and four concentrates with different NFC sources. Results: No differences in dry matter intake, feed efficiency, ruminal pH, hematological and metabolic profile were observed between treatments. Rumen pH was higher than 6.0, confirming the absence of ruminal acidosis. Milk yield (energy-corrected), protein, and total solids were higher for MES vs. C. Conclusions: None of the NFC sources tested compromised the ruminal or systemic health of the cows, while MES improved milk yield and quality.

Resumen Antecedentes: las limitaciones nutricionales del Cenchrus clandestinus (alta concentración de proteína y baja densidad energética) hacen necesario suplementar las vacas con fuentes de carbohidratos no fibrosos (NFC) para mejorar su desempeño productivo. Sin embargo, esta suplementación puede generar acidosis ruminal. Objetivo: evaluar el reemplazo parcial de maíz (Zea mays, ZM) por sorgo (Sorghum vulgare, SV), yuca (Manihot esculenta, MES) o pulpa cítrica (Citrus sp., C) sobre la producción de leche y su calidad, el pH ruminal y la salud de vacas en pastoreo. Métodos: ocho vacas Holstein fueron evaluadas empleando un diseño en cuadrado latino de 4 x 4 durante los primeros 60 días de lactancia. Los tratamientos (raciones isoenergéticas, 1,45 ± 0,003 Mcal NEL/kg MS) consistieron de una mezcla de forraje y cuatro concentrados con diferentes fuentes de NFC. Resultados: no se observaron diferencias entre tratamientos en cuanto a consumo de materia seca, eficiencia alimenticia, pH ruminal, ni perfiles hematológico y metabólico. El pH ruminal fue mayor a 6,0; confirmando la ausencia de acidosis. La producción de leche (corregida por energía), proteína, y sólidos totales fue mayor para MES vs. C. Conclusiones: ninguna de las fuentes de NFC evaluadas comprometieron la salud ruminal o sistémica de las vacas, y MES mejoró la producción de leche y su calidad.

Resumo Antecedentes: as limitações nutricionais do Cenchrus clandestinus-alta concentração de proteína e baixa densidade de energia- faz necessário suplementar às vacas com fontes de carboidratos não-fibrosos (NFC) para melhorar o desempenho produtivo. No entanto, essa suplementação pode gerar acidose ruminal. Objetivo: avaliar a substituição parcial do milho (Zea mays, ZM) por sorgo (Sorghum vulgare, SV), mandioca (Manihot esculenta, MES) ou polpa cítrica (Citrus sp., C) na produção e qualidade do leite, pH ruminal e a saúde de vacas em pastejo. Métodos: oito vacas Holandesas foram avaliadas empregando um delineamento em quadrado latino 4 x 4 durante os primeiros 60 dias de lactação. Os tratamentos (rações isoenergéticas, 1,45 ± 0,003 Mcal NEL/kg DM) consistiram de uma mistura de forragem e quatro concentrados com diferentes fontes de NFC. Resultados: não foram observadas diferenças entre os tratamentos no consumo de matéria seca, eficiência alimentar, pH ruminal, perfil hematológico e metabólico. O pH ruminal foi superior a 6,0; confirmando a ausência de acidose ruminal. A produção do leite (corrigida para energia), proteína e sólidos totais foi maior para MES vs. C. Conclusões: nenhuma das fontes de NFC avaliadas comprometeu a saúde ruminal e sistêmica das vacas, embora o MES melhorou a produção e qualidade do leite.

Molecular characterization and core collection evaluation of Manihot esculenta Crantz / Caracterização molecular e avaliação de coleção nuclear de Manihot esculenta Crantz

Cassava is one of the most important subsistence crops in tropical regions. It is necessary to preserve and to know the genetic diversity existent for the adequate use of genetic resources. The evaluation of genetic diversity among genotypes results in information about potential parents in breeding programs, allows duplicates identification, and facilitates germplasm exchange between research institutions. The objective of this study was to characterize the genetic diversity of cassava accessions of North Brazil region. A total of 106 accessions were analyzed using ten microsatellite markers. The genetic parameters estimated were: expected heterozygosity (HE), observed heterozygosity (HO) and polymorphic information content (PIC). Clustering was performed using the UPGMA and Neighbor-Joining (NJ) method. Bayesian analysis, analysis of principal coordinates and identification of a core collection were also used. The ten loci amplified 8,40 alleles on average. The average heterozygosity estimates were: HE = 0.71, HO = 0.58 and PIC = 0.72. Genetic distances ranged from 0.158 to 0.908. Six (5,66%) accesses were redundant. Clustering and dispersion analysis didn't differentiate bitter from sweet cassava, and there wasn't correlation between groups and collect origin. The core collection consisted of 22 individuals that represented 94% of total allelic diversity and 20,75% of the base collection. The results indicate high dissimilarity between the accessions and allowed the detection of redundant genotypes, showing the use of genetic markers as informative tools for the management of collections. (AU)

A mandioca é uma das mais importantes culturas de subsistência em países tropicais. É preciso conservar e conhecer a diversidade genética para o uso adequado dos recursos genéticos. A avaliação da diversidade genética entre os genótipos resulta em informações sobre potenciais genitores em programas de melhoramento, possibilita a identificação de duplicatas, além disso, facilita o intercâmbio de germoplasma entre instituições de pesquisa. O objetivo deste trabalho foi caracterizar a diversidade genética dos acessos de mandioca da Região Norte do Brasil. Foram analisados 106 acessos por meio de dez marcadores microssatélites. Os parâmetros de diversidade genética estimados foram: heterozigosidade esperada (HE), heterozigosidade observada (HO) e conteúdo de informação polimórfica (PIC). Agrupamentos foram realizados pelo método UPGMA e Neighbor-Joining (NJ). Utilizou-se também análises bayesianas, dispersão por coordenadas principais e a identificação de uma coleção nuclear. Os dez locos amplificaram 8,40 alelos em média. A média das estimativas de diversidade foram altas: HE = 0,71, HO = 0,58 e PIC = 0,72. As distâncias genéticas variaram de 0,158 a 0,908. Seis (5,66%) acessos estão redundantes. Os agrupamentos e análises de dispersão não evidenciaram distinção entre variedades bravas e mansas e não foi identificada estrutura genética correspondente a origem dos acessos. A coleção nuclear foi formada por 22 indivíduos, que representaram 94% da diversidade alélica total e 20,75% da coleção base. Os resultados indicam alta dissimilaridade entre os acessos e permitiram a detecção de genótipos redundantes, mostrando o uso de marcadores genéticos como ferramentas informativas para o manejo de coleções. (AU)

Determinação espectrofotométrica de Cobre(II) em aguardente de mandioca (Tiquira) / Spectrophotometric determination of Copper (II) in manioc spirit (Tiquira)

RESUMO A pesquisa descreve a reação espectrofotométrica do complexo Cu(II)-PAN (1-(2-piridilazo)-2-naftol) e determina a concentração de cobre (II) em aguardente de mandioca (Tiquira). Para isso, dimensionamos a reação para os estudos de absorção do complexo, pH, estabilidade, proporção estequiométrica, interferentes, correlação e recuperação. Após essa etapa, determinamos a concentração de cobre(II) em cinco amostras de bebidas destiladas artesanalmente de cinco municípios do Estado do Maranhão. O resultados mostram que o complexo absorve em 548 nm em pH 6, é estável em um tempo de 7 horas em proporções estequiométrica mínima de 1:1 do ligante e metal, possui limite de detecção em 3,3 X 10-2 mg L-1, faixa de linearidade de 1 X 10-6 a 1 X 10-5 mol L-1, correlação (R2= 0,9990), desvio padrão=0,0035 e recuperação em 104,54 ± 7,01 e os principais íons interferentes são o ferro (III) e o cobalto (II). Na aguardente, constatamos que o teor de cobre está acima do permitido pela legislação brasileira.

SUMMARY The search describes the spectrophotometric reaction of the Cu (II)-PAN (1-(2-pyridilazo) -2-naphthol) complex and determines the concentration of copper (II) in manioc spirit (Tiquira). For this, we dimensioned the reaction for the studies of complex absorption, pH, stability, stoichiometric ratio, interferences, correlation, and recovery. After this step, we determined the concentration of copper (II) in five samples of beverages distilled artisanal from five municipalities of the State of Maranhão. The results show that the complex absorbs at 548 nm at pH 6, is stable at a time of 7 hours in minimum 1:1 stoichiometric proportions of the binder and metal, has a detection limit in 3.3 X 10-2 mg L-1, range (R2= 0.9990), standard deviation= 0.0035 and recovery at 104.54 ± 7.0, and the main interfering ions are iron (III) and cobalt (II). In the brandy, we find that the copper content is above that allowed by Brazilian legislation.

Molecular Detection of Mycological Content in Ready to Eat Garri in Bayelsa State

Background and Objective: Garri is a powdery carbohydrate-based food material of cassava root tubers (Manihot esculenta Crantz) consumed predominantly in West African countries. It can be processed with palm oil rich in carotenoid (Light-yellow) or without palm oil (Creamy-white). In Nigeria, garri is widely acceptable and consumed by both the poor, the middle men or average Nigerian, and also the rich because it serves as a major source of carbohydrate.The study aimed at detecting fungal strains that produce mycotoxins in garri sourced from Southern Ijaw Local Government Area of Bayelsa State.Materials and Methods:A total number of fifty freshly prepared and market displayed-garri samples were collected and processed using standard mycological techniques and Polymerase Chain Reaction from the 23 villages that constitute the LGA.Results:Results showed that the moulds isolated in yellow garri samples in this study were; Aspergillus spp9(37.50%),Cladosporiumspp 5(20.83%),Fusarium spp4(16.67%),Penicillus spp3(12.50%),Rhizopus spp2(8.30%) and Mucor spp1(4.17%),while those isolated in the white garri samples were; Aspergillus spp 6(25%), Penicilliumspp 8(33.3%), Cladosporium spp 4(16.7%), Rhizopus spp 2(8.3%),Mucor spp 1(4.1%), Alternaria spp 2(8.3%) and Fusarium spp 1(4.1%) with predominance of Penicilliumand Asperigellus species. Twenty samples subjected to molecular analysis to determine the Internal Transcribed Spacerregion (ITS) and characterization of the fungal strains were all positive (100%).Conclusion:Fungal contamination on garri mostly results from unhealthy post-processing activity basically from poor packaging and storage. Mycotoxins from fungal strains have serious health implications on humans therefore it is paramount that proper packaging and storage of this product is publicized to reduce its mycological contamination.

Studies on the development of cassava based reconstituted dry starch sago with modified starch as binder and characterization of its physico-functional properties

Aim: The present study was conducted to investigate the status and diversity of plant species used for rearing of Eri silkworm and their traditional management in the homegardens of Mishing tribe.Methodology: A total of 45 homegardens from three villages were surveyed randomly which were primarily associated with rearing of Eri silkworm. Vegetation was studied using quadrat method. The data on traditional knowledge associated with the management of plants species for rearing of Eri silkworm were collected using semi structured questionnaires. Results: The average size of studied homegardens was 0.35 ha. A total of 243 plant species were recorded from the studied homegardens of which six species were used as food plants for rearing of Eri silkworm and 10 species were used in construction of mountage. Trees related to Eri culture contributed to 37.47% of the total importance value index (IVI) in the studied homegardens. Heteropanax fragrans (Roxb.) Seem and Ricinus communis L. were the primary food plants of Eri silkworm and were found to be dominant in the homegardens. Activities such as land preparation, sowing, pruning, weeding and watering are carried out for the management of Eri silkworm food plant species and were found to vary for different species. Interpretation: There is an urgent need to document the indigenous knowledge and traditional practices associated with the management of host and food plants used in the rearing of Eri silkworm in the present day context as it is a part of their cultural heritage and should be reoriented through integration of modern farming technique.

Resistance of cassava genotypes to Vatiga manihotae (Drake 1922) (Hemiptera: Tingidae)

ABSTRACT Vatiga manihotae (Drake 1922) (Hemiptera: Tingidae) is an important cassava pest due to the great potential damage and the increasing population in recent years. However, few studies about bioecology and control of the cassava lace bug have been conducted and their results don't provide adequate control strategies. An alternative to maintain the population below economic injury levels is through the adoption of host plant resistance. To improve the understanding about the bioecology and find new sources of resistance in cassava, the biological parameters and demographics of V. manihotae on five cassava genotypes (Santa Helena, MEcu 72, Col 22, Clone 02 and Clone 03) under controlled conditions (25±2°C, 14L/10D) were evaluated. Duration and viability of the stages, the period egg-adult, sex ratio, the pre-oviposition period, fecundity and longevity of male and female was determined, and a fertility life table was prepared. Insects fed on MEcu 72 showed increased nymphal, egg-adult, and pre-oviposition periods and reduced female fecundity and longevity in comparison to the other genotypes. Demographic parameters (Ro, rm, T, DT) showed a significant impact on the growth potential of V. manihotae fed on MEcu 72 indicating that the populations would diminish over time. The combined effect of these parameters indicated that MEcu 72 has resistance on V. manihotae specimens hindering their development.