Identification of genomic regions associated with early plant vigour in lentil (Lens culinaris)

Lentil is one of the most important food legume species, however its genetic and genomic resources remained largely uncharacterized and unexploited. In the past few years, a number of genetic maps have been constructed and marker resources have been developed in lentil. These resources could be exploited for understanding the extent and distribution of genetic variation in genus Lens and also for developing saturated and consensus genetic maps suitable for quantitative trait loci (QTL) mapping and marker-assisted selection. The present study aims to enrich polymerase chain reaction-based linkage map of F10 recombinant inbred lines (RILs) population of 94 individuals derived from cross WA8649090 9 Precoz and identification of QTLs linked to early plant vigour traits. Of the 268 polymorphic markers (93 simple sequence repeats (SSR), three inter-simple sequence repeats (ISSRs) and 172 random amplified polymorphic DNA (RAPDs)), 265 (90 SSRs, three ISSRs and 172 RAPDs) were mapped on seven linkage groups, varying in length between 25.6 and 210.3 cM, coverage of 809.4 cM with an average marker spacing of 3.05 cM. The study also reported assigning of 24 new cross-genera SSRs of Trifolium pratense on the present linkage map. The RILs along with the parents were screened for shoot length, root length, seedling length, dry weight, number of leaves and number of branches based on two replications under polyhouse conditions. A QTLhotspot consisting of six QTLs for shoot length (cm), root length (cm) and seedling length (cm) was observed between a map distances of 56.61 and 86.81 cM on LG1.

Effect of Seed Hydropriming on Seedling Emergence and Growth of Chickpea (Cicer arietinum L.) under Adverse Climatic Condition of Drought and Salinity

Aim: Assessment of influence of seed hydropriming in seed and seedling vigour enhancement for stress tolerance in chickpea which is important for successful crop production under erratic climate change causing drought and salinity stress severely affecting the seedling emergence and establishment especially in arid and semi arid regions of the world. Study Design: A three factorial randomised block design was used in the study, involving seed hydropriming treatment, chickpea varieties and growth conditions. Place and Duration of the Study: The experiment was conducted in Department of Seed Science and Technology, University of Agricultural Sciences, Dharwad, India, during the year 2018. Methodology: Six months old chickpea seeds of variety JG-11 and Annigeri-1 were hydroprimed for 12 hours at 25°C in dark condition. The primed and unprimed control seeds are sown under normal, drought and salinity conditions imposed in pots under controlled conditions. The data recorded were analysed for Analysis of Variance (ANNOVA). Results: The result of the experiment revealed that, upon seed hydropriming an average of 19 per cent increase in seedling emergence and 53.3 per cent increase in seedling vigour index was observed as compared to unprimed control seeds irrespective of variety and the abiotic stress conditions.

Characterization of cultural beneficial bacterial diversity for plant growth promoting attributes associated with rice rhizosphere

Aim: The study was undertaken to isolate, characterize and molecularly identify plant growth promoting rhizobacteria (PGPR) associated with rice rhizosphere occurring in Gangetic plains of the country. Methodology: One hundred forty three plant growth promoting rhizobacteria were isolated on various culture media and characterized culturally and morphologically through Scanning Electron Microscope. These rhizobacterial isolates were further screened for plant growth promoting activities like HCN production, siderophore production and phosphate solubilisation. The 16S rDNA sequencing was done to decipher phylogenetic relationship among 19 selected PGPRs. Besides, these were also tested for anti-oxidative enzyme production to mitigate deleterious effects of various stresses on plant growth and metabolism. Results: Nineteen potential plant growth promoting rhizobacteria were characterized for plant growth promoting attributes and were indentified at molecular level. Rice is well colonized by bacteria mainly Bacillus spp., Pseudomonas spp., Burkholderia sp., and Acinetobactor spp., Rice seeds treated with microbial consortium of MAU 143 + MRT 84 recorded in increased antioxidant production–SOD activity (0.02 U mg−1 f.w.t.), POX activity (0.16 U mg−1 f.w.t.), POP activity (0.06 U mg−1 f.w.t.) and TPC assay (1.17 µg gallic acid mg-1 extract) which might have stimulated the growth of radical (2.2 cm) and plumule (1.6 cm) over control. These three PGPRs viz., MAU 143, MRT 84 and MRT 92 strain showed great potential to improve antioxidant and total polyphenol production and seed vigour of rice seedlings. The identified rhizobacterial strains may be used for plant growth promotion and improvement in nutrients mobilization and oxidative stresses in rice production. Interpretation: The study suggested that plant growth promoting rhizobacteria isolated from rice rhizosphere have greater potential to improve soil nutrients status while provide resistance against infection of pathogenic microbes due to production of anti-oxidative enzymes and phenolic compounds in rice seedlings.

Spermine induced protection of onion seed vigour and viability during accelerated ageing

Aim: The aim of the present study was to investigate the role of spermine, a polyamine as a protective agent on accelerated ageing of onion seeds. Methodology: Onion seeds variety Pusa Riddhi was primed with six concentrations of spermine (0.10 mM to 1.25 mM) and also with hydration and halopriming (2% K2HPO4). Hydrated, haloprimed and un-primed seeds were used as control. The primed and control seeds were accelerated aged at 45 oC and 100 % RH for 72 hr. Seed quality was assessed in control, freshly primed seeds, and in primed seeds subjected to accelerate ageing. Results: All priming treatments enhanced the seed quality, there was 2.34–20.33 % increase in germination. Seed priming with 2% K2HPO4 had highest seed quality improvement which was at par with 1.25 mM spermine primed seeds. Enhanced seed vigour and the activity of antioxidant enzymes over un-primed seeds was observed in both 2% K2HPO4 and spermine primed seeds over unprimed seds. Seeds primed with 1.25 mM spermine recorded 66.66 % and 650 % increase in the activity of ROS scavenging enzymes SOD and POD respectively, but they were at par with halopriming. After accelerated ageing, deterioration in seed quality was minimal in seeds primed with spermine. Seeds primed with 1.25 mM spermine recorded 21.33% higher germination, 62.10 % higher speed of germination, 26.56 % longer seedlings, 13.68 % heavier seedlings and 175 % and 200 % higher SOD and POD activity as comparised to un-primed seeds. Seeds primed with 1.25 mM spermine also performed better over halopriming and hydropriming treatments. Interpretation: Onion seed priming with 1.25 mM spermine was most effective treatment in enhancing the seed germination and vigour under accelerated ageing conditions.

Physiological changes in seeds and seedlings of pumpkins submitted to salt stress / Alterações fisiológicas em sementes e mudas de abóboras submetidas a estresse salino

Salinity is one of the most limiting environmental factors for plant growth in semi-arid regions.Excessofsalts reduces water potential, causes physiological drought and can influence germination and initial growth of plants. The objective of this work was to study physiological and metabolic changes in seeds and seedlings of pumpkin (Cucurbita pepo cultivars Caserta and Redonda and C. maxima cv. Coroa)in a saline condition of salt stress. Thus, we it was quantified germination parameters; seedlings growth; seeds and seedlings respiration; degradation of total soluble sugars, reducing sugars and total proteins in cotyledons and the activity ascorbate peroxidase (APX), glutathione-S-transferase (GST) and catalase (CAT) during germination and initial growth of the pumpkin species studied in saline conditions. The experimental design was totally randomized in a factorial scheme 6x3, with six electrical conductivities (0; 2; 4; 6; 8 e 10 dS.m-1) and three cultivars (Redonda, Caserta and Coroa). Salinity did not influence the rate of seed respiration during the germination, although seedlings respiration decreased, as well as its vigour. Total sugars were degraded, while there was accumulation of reducing sugars and proteins in cotyledons of germinating seeds in salt solutions. Increased electrical conductivity reduced APX activity in the embryo and CAT in cotyledons, but did not influence GST. Pumpkin seedlings showed low tolerance to salt stress.

A salinidade é um dos fatores limitantes para o crescimento das culturas nas regiões áridas e semiáridas. O excesso de sais provoca uma redução no potencial hídrico e causa seca fisiológica e influencia na germinação e crescimento inicial de plântulas Objetivou-se estudar possíveis alterações fisiológicas e metabólicas em sementes e plântulas de abóboras (Cucurbita pepo cultivars Caserta and Redonda and C. maxima cv. Coroa), Sendo assim, avaliou-se em sementes e plântulas os parâmetros da germinação (porcentagem e velocidade); crescimento de plântulas; respiração de sementes e plântulas; degradação de açúcar solúveis totais, açúcar redutores e proteínas totais nos cotilédones e atividade das enzimas ascorbato peroxidase (APX), glutationa-S-transferase (GST) e catalase (CAT) durante a germinação e crescimento inicial das cultivares de abóbora em soluções salinas. O delineamento experimental foi inteiramente casualizado em esquema fatorial 6x3, com seis condutividades elétricas (0; 2; 4; 6; 8 e 10 dS.m-1) e três cultivares (Redonda, Caserta e Coroa). A salinidade não influenciou a taxa de respiração das sementes durante a germinação, no entanto, a respiração das plântulas diminuiu, assim como o vigor das plântulas. Houve degradação dos açúcares totais e acúmulo de açúcares redutores e proteínas em cotilédones de sementes submetidas a soluções salinas. O aumento da condutividade elétrica induziu redução da atividade de APX no embrião e de CAT nos cotilédones, mas não influenciou GST. Cultivares de aboboras apresentaram baixa tolerância ao estresse salino.

Influence of Seed Pelleting on Physiological Seed Quality Improvement in Bael (Aegle marmelos (L.) Corr.) the Endangered Medicinal Tree

Aim: Bael is an endangered medicinal tree with multipurpose utility propagated through seeds. Hence attempts were to improve the vigour of the seed through seed pelleting with ecofriently organic products. Study Design: A Factorial completely randomized design (FCRD) for laboratory experiments and RBD for nursery studies with five replication with five replications. Place and Duration of Study: The laboratory and nursery experiment was conducted at the Department of Seed Science and Technology, Tamil Nadu Agricultural University, Coimbatore during 2012-13. Methodology: The seeds were pelleted with botanical leaf powders viz., karisilanganni (Eclipta prostrate), avaram (Cassia auriculata), arappu (Albizia amara), neem (Azadirachta indica), biofertilizers viz., azophos, phosphobacteria and biocontrol agents viz., Trichoderma viride and Pseudomonas fluorescens along with unpelleted seeds. Results: The results showed that among the treatments arappu pelleting enhanced the germination (76%) and seedling quality characters viz., root length (13.0 cm), shoot length (9.9 cm), dry matter production (318 mg) and vigour index (1740) compared to control followed by neem and phosphobacteria pelleting. The treatment scored as best also performed better at polypot nursery. Conclusion: Our data show that arappu pelleting enhanced seed quality compared to control

Viabilidad y germinación de semillas de Hechtiaperotensis (Bromeliaceae) / Viability and germination of Hechtia perotensis (Bromeliaceae) seed

ResumenPoblaciones endémicas de Hechtiaperotensis se han descrito en Puebla y Veracruz, México. La recolección de semillas de buena calidad permite su uso en conservación, investigación y restauración ecológica. Algunos compuestos para evaluar la calidad de las semillas silvestres y endémicas, como nitrato de potasio (KNO3) y ácido giberílico (AG3), se utilizan para incrementar la germinación de las semillas y disminuir la latencia. La prueba de cloruro de trifeniltetrazolio (tetrazolio) se correlaciona con la viabilidad de las semillas porque se basa en la actividad de las deshidrogenasas de tejidos vivos que catalizan la respiración mitocondrial. El objetivo de este estudio fue conocer el tamaño y el peso de las cápsulas y las semillas y la germinación y viabilidad de las semillas de H. perotensis recolectadas en Veracruz en 2012 y 2015. Las hipótesis fueron (1) que la germinación y la viabilidad de las semillas son independientes del año de recolecta, (2) que hay una concentración adecuada de tetrazolio para identificar la viabilidad de las semillas y (3) que el pretratamiento con KNO3 o AG3 incrementa la germinación de las semillas. La germinación se evaluó con un diseño completamente al azar con tres tratamientos (testigo y promotores de la germinación KNO3 0.2 % y AG3 500 mg/L), cuatro tratamientos para la prueba de viabilidad (testigo, 0.2, 0.5 y 1.0 % de tetrazolio) y seis repeticiones de cada tratamiento. La germinación se evaluó en 100 semillas y la viabilidad en 25. Los resultados entre y dentro de años se analizaron con ANDEVA y prueba de comparación múltiple de medias de Tukey. La proporción de semillas no germinadas se cuantificó junto con el número de plántulas normales y anormales, semillas con embrión viable o sin él, y con viabilidad baja o sin viabilidad. En promedio la muestra recolectada en 2012 tuvo 36 % de semillas con embrión viable, 7 con viabilidad baja, 24 % no viables y 33 % sin embrión. Este resultado fue significativamente diferente al de 2015, que presentó 87 % de embriones viables, 10 % con viabilidad baja, 0 % no viables y 3 % sin embrión. La germinación también fue significativamente diferente entre los años (22 y 92 %). Los tratamientos pregerminativos no modificaron la germinación. La germinación y la viabilidad de las semillas de H. perotensis varían significativamente entre los años de recolecta.

Abstract:Endemic populations of Hechtiaperotensis have been described in Puebla and Veracruz, Mexico. Good quality seed collections can be used in conservation, research and ecological restoration. To evaluate seed quality of wild and endemic species, some compounds are used as effective promoters of germination, such as potassium nitrate (KNO3) and gibberellic acid (AG3), because they increase seed germination capacity and reduce latency. The triphenyl tetrazolium chloride (tetrazolium) test correlates seed viability because it is based on the activity of dehydrogenases in live tissues that catalyze mitochondrial respiration. The objective of this study was to obtain information on size and weight of capsules and seeds and seed germination and viability of H.perotensis, collected in Veracruz in the year 2012 and 2015. The hypotheses were 1) that seed germination and viability are independent of the year of collection, 2) that there is a tetrazolium concentration that can identify seed viability better than others, and 3) that pretreatment with KNO3 or AG3 improves seed germination. Seed germination was assessed using a completely randomized design with three treatments (control and the germination promoters 0.2 % KNO3 and 500 mg/L AG3), four treatments for the viability test (control, 0.2, 0.5 and 1.0 % of tetrazolium) and six replicates for each treatment. A total of one hundred seeds for germination experiments, and 25 seeds for the viability test were used. The results between and within years were analyzed with ANOVA and multiple comparison with the Tukey test. The proportion of non-germinated seeds was quantified along with the number of normal and abnormal seedlings, seeds with viable embryo, seeds without embryo, and seeds with low or no viability. On average, for the 2012 collected sample, 36 % had viable embryos, 7 % had low viability, 24 % were not viable and 33 % had no embryo. This result was significantly different from the 2015 sample, for which 87 % of seed showed viable embryos, 10 % had low viability, 0 % was not viable and 3 % had no embryo. Seed germination was also significantly different between years (22 and 92 %) Pregerminative treatments did not improve germination. Seed germination and viability of H. perotensis significantly varied between years of seed collection. Rev. Biol. Trop. 65 (1): 153-165. Epub 2017 March 01.

Compatibilidade fenotípica entre cultivares de pereiras europeias eporta-enxertos de marmeleiro / Phenotypic compatibility among european pear cultivars and quince rootstocks

A cultura da pereira (Pyrus communisL.) possui grande potencial de expansão no sul do Brasil devido às condições climáticas e de solo. A carência de informações a respeito da(s) melhor(es) combinação(ões) de cultivares 'copa de pereiras europeias' e porta-enxertos de marmeleiro em relação à compatibilidade de enxertia é um dos fatores que tem limitado o cultivo de pera no país. A utilização de porta-enxertos de marmeleiros apresentam as vantagens de redução do vigor e rápida entrada em produção, porém, quando enxertados com algumas cultivares de 'pereira europeia', pode acarretar incompatibilidade de enxertia. O trabalho foi realizado com o objetivo de avaliar fenotipicamente a compatibilidade morfológica entre cultivares 'copa de pereiras europeias' e porta-enxertos de marmeleiro através das variáveis de crescimento das plantas, como o incremento de diâmetro (mm) do tronco da cultivar e do porta-enxerto; diferença de diâmetro entre a cultivar e o porta-enxerto; incompatibilidade 'translocada'; incompatibilidade 'localizada'; e análise da conexão vascular no ponto de enxertia pela imersão em solução corante de Ácido Fuccínico 0,08%. Os experimentos foram conduzidos em pomares de pereiras europeias na região de Urupema, estado de Santa Catarina, durante os ciclos de cultivo 2011/12, 2012/13 e 2013/14. As combinações de cultivares de pereiras europeias e porta-enxertos avaliados foram a 'Abbè Fetel'/'Adams', 'Decana du Comice'/'Adams', 'Clapp's Favourite'/'EMA', 'Rocha'/'Adams', 'Packham´s Triumph'/'EMA' e 'Santa Maria'/'Adams'. A combinação 'Clapp´s Favourite'/'EMA' apresentou incompatibilidade do tipo 'localizada' pela descontinuidade vascular na região de união do enxerto, impedindo a passagem do corante. As combinações 'Rocha'/'Adams' e 'Abbè Fetel'/'Adams' não apresentaram incompatibilidade de enxertia. Nessas combinações, foram observadas união vascular contínua entre as cultivares e os porta-enxertos. As combinações ...

The pear (Pyrus communis L.) crop offers an expansive market opportunity in southern Brazil, because of amicable climatic and soil conditions. However, the lack of studies on compatibility of european pear cultivars and rootstocks is one of the limiting factors on the development of the pear crop in southern Brazil. The use of quinces as rootstocks has the advantages of vigor reduction and earlier bearing trees. However, some of these combinations can present some incompatibility graft. The objective of this study was to evaluate phenotypicaly the morphological compatibility among european pear cultivars and quince rootstocks. The evaluated variable were the section increment of cultivars and rootstocks trunk diameter at the graft union; the diameter difference between scion and cultivars and rootstocks; 'translocated' incompatibility; 'located' incompatibility; and the vascular connection of the graft union by immersion of the base of the plants (under the graft union) in a 0.08% Fuccinic acid solution. The experiments were conducted in an european pear orchards in the region of Urupema municipality, state of Santa Catarina, during the 2011/12, 2012/13 and 2013/14 growing seasons. The european pear cultivars and rootstocks evaluated were: 'Abbé Fetel'/'Adams', 'Decana du Comice'/'Adams', 'Clapp's Favourite'/'EMA', 'Rock'/'Adams', 'Packham's Triumph'/'EMA' and 'Santa Maria'/'Adams'. 'The Clapp´s Favourite'/'EMA' combination showed a `located incompatibility by descontinued vascular graft region, preventing the dye translocation. 'The Rocha'/'Adams' and 'Abbè Fetel'/'Adams' combinations did not present graft incompatibility, showing continued vascular union and no vascular disruption between cultivars and rootstocks. The 'Santa Maria'/'Adams', 'Decana du Comice'/'Adams' and 'Packham´s Triumph'/'EMA' combinations showed a good graft union region with clear and continued bark and wood bond lines. The 'Clapp´s Favourite'/'EMA' ...

Physiological and phytosanitary potential of rocket seeds / Potencial fisiológico e fitossanitário de sementes de rúcula

The objective of this study was to evaluate the physiological and sanitary quality of seeds of rocket; the research was done at the Laboratory of Seed Analysis and greenhouse of the Department of Plant Science, Federal University of Pelotas (UFPel). Four lots of the cultivar "Antonella'' were tested for following features: initial and final moisture content, germination rate, first count of germination, accelerated aging with saline solution, dry matter contents, seedling shoot and root length, emergence speed index, emergence of seedlings in substrate, electrical conductivity and sanitary condition. A completely randomized design with four replications was used for all tests done and means were compared by Tukey test (P≤0.05). For all tests performed it was concluded that despite changes in the ranking of the best lots, there was agreement regarding the indication of the inferiority of the lot 3 in all tests and it was also observed that the incidence of fungi associated with seeds of rocket interfere with the physiological quality of the lots.

O objetivo nesta pesquisa foi avaliar a qualidade fisiológica e sanitária de sementes de rúcula. O trabalho foi conduzido no laboratório e em casa de vegetação do Departamento de Fitotecniada Universidade Federal de Pelotas (UFPel). No ensaio, foram utilizados quatro lotes de sementes de rúcula da cultivar 'Antonella', sendo efetuados os seguintes testes: grau de umidade inicial e após o envelhecimento acelerado, germinação, primeira contagem de germinação, envelhecimento acelerado com solução salina, massa seca da parte aérea e de raiz de plântulas, comprimento da parte aérea e de raízes de plântulas, índice de velocidade de emergência, emergência de plântulas, condutividade elétrica e teste de sanidade, em delineamento experimental inteiramente casualizado, com quatro repetições, sendo que as médias foram comparadas pelo teste de Tukey (P≤0,05). Apesar das alterações na classificação dos melhores lotes, nos testes analisados, verificou-se concordância quanto à indicação da inferioridade do lote 3 em todas as avaliações. Verificou-se que a incidência dos fungos associados às sementes de rúcula interfere na qualidade fisiológica dos lotes.

Superação da dormência tegumentar de sementes de Piptadenia viridiflora (Kunth) Benth pela escarificação química / Overcoming tegumentary seed dormancy Piptadenia viridiflora (Kunth) Benth by chemical scarification

O objetivo deste trabalho foi avaliar os efeitos de diferentes períodos de imersão de sementes de Piptadenia viridiflora (Kunth) em ácido sulfúrico visando a maximização de valores de germinação, emergência e vigor de plântulas. Para o ensaio conduzido em laboratório, foi definido o delineamento inteiramente casualizado, com quatro repetições, sendo a parcela experimental constituída por uma placa de Petri, contendo 50 sementes, totalizando 200 sementes por tratamento. As placas de Petri foram mantidas em câmara BOD a temperatura de 25 ºC, com fotoperíodo de oito horas. Para avaliação em casa de vegetação foi instalado um ensaio com delineamento em blocos casualizados, com quatro repetições, sendo a parcela experimental constituída de 50 sementes distribuídas em fileira, totalizando 200 sementes por tratamento. Avaliou-se o efeito de períodos de imersão (15, 30, 45, 60 minutos) das sementes, em ácido sulfúrico (98 %), na germinação, IVG (Índice de Velocidade de Germinação), emergência, IVE (Índice de Velocidade de Emergência) e vigor das sementes (comprimento do caule, peso da massa fresca da raiz e parte aérea, peso da massa seca da parte aérea, peso de massa fresca total) e índice Spad. A escarificação química por exposição ao ácido sulfúrico concentrado foi eficiente para superação da dormência dessa espécie, promovendo elevação da porcentagem de todos os parâmetros avaliados. A maximização de valores foi verificada para o período de imersão entre 23 e 38 minutos de exposição à escarificação química.

The aim of this work was to evaluate the best immersion time in sulfuric acid to maximize germination, emergence and vigor values of seedlings. It was evaluated immersion time (15, 30, 45, 60 min) in sulfuric acid (98%) to seed germination, emergency, IVG (germination speed index), IVE (emergence speed index), seed vigor (stem length, fresh mass weight of roots and shoots, dry mass weight of shoots, total fresh mass weight) and Spad index. The laboratory trial was defined by completely randomized design with four replicates, and the plot consists of a Petri dish (145 mm diameter) containing 50 seeds, totalizing 200 seeds per treatment. Petri dishes were kept in BOD incubator at 25°C with a photoperiod of eight hours. For evaluation of emergency, it was conducted an experiment with a randomized block design with four blocks, and the plot consisted of 50 seeds. The sulfuric acid was efficient in overcoming the dormancy of the species, increasing the percentage of all characteristics evaluated. The efficiency of chemical treatment with concentrated sulfuric acid depends on the immersion time, and the period between 23 and 38 min is most suitable to provide higher percentages of germination and emergence.

Emergência de plântulas de Bauhinia divaricata L. em diferentes posições e profundidades de semeadura / Seedling emergence of Bauhinia divaricata L. at different sowing positions and depths

Bauhinia divaricata L. é uma espécie arbórea amplamente distribuída no Brasil, de alto valor ornamental e econômico, se propaga por meio de sementes, mas a germinação tem sido pouco pesquisada. Dessa forma, no presente trabalho o objetivo foi verificar o efeito da posição e profundidade de semeadura sobre a emergência e o desenvolvimento inicial de plântulas de B. divaricata. O delineamento experimental foi inteiramente ao acaso, com os tratamentos distribuídos em esquema fatorial 3 x 6 (posições e profundidades de semeadura), sendo as posições de semeadura constituídas por semente com o hilo voltado para baixo (HB), para cima (HC) e para o lado (HL) nas profundidades de um, dois, três, quatro, cinco e seis centímetros. Na avaliação do efeito dos tratamentos determinou-se a emergência, primeira contagem (PC), índice de velocidade de emergência (IVE), comprimento e massa seca da parte aérea e das raízes de plântulas. As posições de semeadura não interferem na emergência das plântulas de Bauhinia divaricata, sendo a profundidade de 1,64 cm a mais indicada para promover maior emergência e crescimento inicial das plântulas.

Bauhinia divaricata L. is a tree widely distributed in Brazil, with high ornamental value and cost. Its propagation is by seeds, which have been little investigated. Thus, this study aimed to investigate the effect of position and depth of the seed at sowing on the process of emergence and seedling vigor of the Bauhinia divaricata L. The experimental design was completely randomized with treatments arranged in a factorial 3 x 6 (positions and sowing depths), and the positions established by sowing seed with the hilum facing downwards (HB), up (HC) and to the side (HL) at depths of one, two, three, four, five and six centimeters. In evaluating the effect of treatment was determined to emergency first count (PC), emergence rate index (IVE), length and dry mass of shoots and roots of seedlings. The positions do not interfere with seeding seedling emergence of Bauhinia divaricata, and the depth of 1.64 cm more indicated to promote greater emergence and early growth of seedlings.

Temperatura inicial de germinação no desempenho de plântulas e mudas de tomate / Germination temperature in tomato seedlings performance

A produção de mudas é uma das etapas fundamentais para o cultivo do tomateiro e pode ser influenciada pela temperatura inicial de germinação. Nesse sentido, o objetivo deste trabalho foi avaliar o efeito desse fator no desempenho de plântulas e mudas de tomate. Foram utilizados quatro lotes de sementes de tomate híbrido Mariana, submetidos aos testes de germinação, envelhecimento acelerado e condutividade elétrica para a avaliação do potencial fisiológico. Após a caracterização dos lotes, as sementes foram submetidas a diferentes temperaturas iniciais de germinação (20-30 alternada, 30, 33 e 35°C constantes) para determinação da curva de embebição e para análise de plântulas por meio do software SVIS®. Sementes submetidas às mesmas temperaturas foram destinadas à produção de mudas e o desempenho destas foi avaliado por meio da velocidade e porcentagem de emergência, altura e massa seca da parte aérea e das raízes. As temperaturas mais elevadas prejudicam o desenvolvimento inicial das plântulas, porém as mudas submetidas às diferentes temperaturas, aos 28 dias após a semeadura, estavam com desempenho semelhante.

Seedling production is an important step for the tomato production and can be influenced by the initial temperature of germination. The aim of this study was to evaluate the effect of this factor in the tomato germination and seedling growth. It was used four seed lots which were tested for germination, accelerated aging and electrical conductivity to evaluate the physiological potential. After lots characterization, seeds were exposed to initial germination temperatures (20-30, 30, 33 and 35°C) and were analyzed by the SVIS® software. The seedling performance was evaluated using the emergence speed index and percentage, height and dry weight of shoots and roots. In general, the higher temperatures decreased the seedlings development. However, 28 days after sowing, the seedlings growth was similar among temperatures.

Condutividade elétrica em função do teor de água inicial de sementes de amendoim / Electrical conductivity and water content in peanut seeds

O vigor de sementes de amendoim (Arachis hypogaea L.) avaliado pelo teste de condutividade elétrica demonstra estreita relação com o desempenho no campo, mas alguns fatores podem afetar o resultado da condutividade elétrica, sendo um destes o teor de água inicial das sementes. Assim, o objetivo deste trabalho foi avaliar o teor de água ou faixa de umidade da semente mais adequado para a avaliação da condutividade elétrica em sementes de amendoim. Quatro lotes de sementes da cultivar 'IAC Tatu ST' e quatro da cultivar 'IAC Runner 886' foram avaliados quanto ao seu potencial fisiológico e posteriormente o teor de água foi ajustado para 5, 7, 9, 11, 13 e 15 por cento, pelo método da atmosfera úmida. O delineamento foi inteiramente casualizado em esquema fatorial 4×6 (lotes × teores de água) para as sementes de cada cultivar, em quatro repetições e os resultados para o fator teor de água foram submetidos à análise de regressão. A maior relação da condutividade elétrica com vigor das sementes ocorreu naquelas com teor de água entre 9 a 15 por cento, de forma que sementes com 5 a 7 por cento de umidade não devem ser submetidas ao teste de condutividade elétrica, porque os lotes expressam alto padrão de germinação e vigor. A condutividade elétrica de sementes de amendoim é influenciada pelo teor de água e a estabilização dos resultados ocorre quando elas estão com teor de água entre 10 e 14 por cento.

The vigor of peanut seeds (Arachis hypogaea L.) assessed by the conductivity test shows close relationship with performance in the field, but some factors may affect the outcome of the electrical conductivity, being one of that the initial water content of seeds. The objective of this study was to evaluate the seed water content most appropriate for evaluating the seed vigor through electrical conductivity test in peanut. Four seed lots of 'IAC Tatu ST' cultivar and four 'IAC Runner 886' were initially evaluated for their physiological potential and subsequently the seed water content was adjusted to 5, 7, 9, 11, 13 and 15 percent by the method of controlled atmosphere. A completely randomized design with treatments arranged in a 4×6 factorial design (seed lots × seed water content levels) for each cultivar and four replications were used. The results for the factor seed water content were subjected to the analysis regression. The higher relationship of electrical conductivity and seed vigor occurred when the seed lots presents seed moisture content varying from 9 to 15 percent. Seeds with 5-7 percent moisture should not be subjected to electrical conductivity test, because lots express high standard germination and vigor. The electrical conductivity of peanut seeds is influenced by the seed moisture content and the stabilization of the results occurs when the seeds have moisture content between 10 and 14 percent.

In vitro evaluation of aqueous seed extract of Psoralea corylifolia L. on seed germination and seedling vigour of maize.

Aqueous seed extract of seeds of P.corylifolia were evaluated for seed germination and vigour index at 10, 20, 30, 40 and 50% concentration for 3,6, 12 and 24hours of treatment in maize seeds. Maximum and significant activity was observed in 20% concentration at 12hours of duration and recorded 88.0% germination and 1398.5 vogour index. Compared to control, it was recorded 72.1% germination and 1010.1 vigour index. In 30 and 40% concentration at 12 hours of duration, significant activity was recorded. In 6 hours of duration, moderate activity was observed in 10, 20, 30 and 40% concentration. No significant activity was observed in 3 hours and 24 hours duration at 10, 20, 30, 40 and 50% concentration of aqueous seed extract.

Differential toxicity of cadmium to mustard (Brassica juncia L.) genotypes under higher metal levels.

Cadmium application inhibited various growth and biochemical parameters in seedlings of five cultivars of Brassica juncia L. with different magnitude at lower Cd supply, however, at higher metal applications the variation in Cd toxicity ranged with minor differences. The seedling vigour index (SVI) was inhibited more severely in Gangotri (62.25% over control) and least in Pusa Jai Kisan (8.95%) at 1.0 mM CdCl2. The SVI of all five mustard cultivars, however, severely inhibited (84.29-91.80%) at 5.0 mM Cd. The root and shoot elongation in 7 days old seedlings were inhibited by 32.39-40.38 and 11.83-56.40% respectively at 1.0 mM CdCl2, whereas the varietal differences in root and shoot elongation were 76.71-82.47 and 71.57-78.91 respectively at 5.0 mM CdCl2. The genotypic differences at lower Cd level were more pronounced in shoot elongation than that in the root elongation. The dry weight and moisture content of the seedlings, however, does not show much varietal differences even at lower Cd level, though the Cd toxicity increased at higher level of Cd application. The metal tolerance index (MTI) and % phytotoxicity of 3 days old seedlings ranged between 43.30-98.37 and 1.63-56.70% respectively at 1.0 mM CdCl2 for different mustard genotypes, whereas at 5.0 mM CdCl2 these factors ranged between 12.26- 20.92 and 80.08-87.74% respectively. The varietal differences of MTI and % phytotoxicity was, however, less pronounced at all the metal levels when the seedling attained an age of 7 days. A similar trend of genotypic variation was noticed in Cd accumulation in the seedlings at lower and higher levels of Cd supply to the seedlings. Amongst some biochemical parameters e.g. photosynthetic pigments, carbohydrates and proteins in the leaves, the photosynthetic pigments i.e. chlorophylls and carotenoids were decreased more drastically. The carbohydrate content of leaves, however, was the least affected component. Our data indicate that the differential toxicity of cadmium to Indian mustard genotypes was dependent on the level of contamination and growth phases.

Qualidade fisiológica e sanitária de sementes de algodoeiro produzidas nas regiões do Triângulo Mineiro e sul de Goiás / Physiological and sanity quality of seeds of cotton produced in regions of the Triângulo Mineiro and south Goiás, Brazil

O presente trabalho teve como objetivo avaliar a incidência de fungos em sementes de algodoeiro, bem como sua influência sobre a germinação, vigor e a emergência de plântulas em condições de campo. As sementes foram obtidas nas regiões produtoras do Triângulo Mineiro e do Sul de Goiás. Para compor os tratamentos, foram utilizadas as sementes com o seu respectivo município produtor: IAC-20 de Centralina-MG, IAC- 20 de Capinópolis-MG, IAC-20 de Grupiara-MG, IAC-21 de Capinópolis, IAC-21 de Bom Jesus-GO, IAC-22 de B. Jesus, Delta Pine de Centralina, Delta Pine de Cachoeira Dourada-GO e Redenção de Capinópolis. Os testes foram realizados em laboratório (sanidade, germinação e vigor) e em campo (emergência de plântulas). Pelos resultados obtidos, concluiu-se que os genótipos e locais avaliados influenciaram na incidência de fungos nas sementes; a cultivar Redenção apresentou a maior incidência de Botriodiplodia theobromae; o município de Grupiara se destacou pela maior qualidade das sementes produzidas; Botryodiplodia theobromae indiretamente reduz a germinação e o vigor por causar a morte de sementes, já as bactérias não afetam a germinação, mas afetam o vigor representado pela emergência, enquanto que os fungos saprófitas reduzem diretamente a germinação e o vigor representado pelo estresse causado pelo envelhecimento acelerado das sementes.

This study aimed to evaluate the incidence of fungi in cotton seed and its effect on the germination and vigour and seedling emergence under field conditions. Seeds were obtained in oil producing regions of Minas Triangle and the South of Goiás, Brazil. To compose the treatments, seeds were with their respective district producer: IAC-20-MG Centralina, IAC-20-MG Capinópolis, IAC -20 Grupiara-MG, IAC-21 Capinópolis, IAC-21-GO of Bom Jesus, IAC-22 B. Jesus, of Delta Pine Centralina, Delta Pine de Cachoeira Dourada, GO and Redemption of Capinópolis. The tests were performed in the laboratory (Health, germination and vigour) and field (emergency). From the results, we concluded that the genotypes and sites evaluated influence the incidence of fungi in seeds; redenção cultivar had the highest incidence of Botriodiplodia theobromae; the city of Grupiara stood out for higher quality seeds produced; Botryodiplodia theobromae indirectly reduces the germination and vigor to cause the death of seeds, since the bacteria do not affect germination but affect the force represented by the emergence, while saprophytic fungi directly reduce the germination and vigor represented by the stress caused by the accelerated aging of seeds

Tratamento fungicida de sementes de soja inoculadas com Colletotrichum truncatum / Fungicide treatment of soybean seeds inoculated with Colletotrichum truncatum

A qualidade sanitária e o potencial fisiológico de sementes de soja são fatores determinantes para o estabelecimento de estandes adequados. Assim, objetivou-se avaliar o desempenho das sementes de soja e o crescimento das plantas após inoculação das sementes com Colletotrichum truncatum e tratamento fungicida via peliculização. As sementes foram inoculadas com C. truncatum utilizando técnica de restrição hídrica e, posteriormente, tratadas com fungicidas e polímero. Os tratamentos utilizados foram carbendazin, fludioxonil+mefenoxan, thiabendazol+thiram, tiofanato metílico, caboxin+thiram e sementes não tratadas. As sementes foram tratadas com e sem polímero. Foram realizadas avaliações de germinação das sementes, teste de frio, emergência de plântulas e sanidade das sementes por meio do Blotter test. As plantas, cultivadas em vasos, foram avaliadas pelo comprimento da parte aérea, da matéria seca de raízes e da parte aérea. O tratamento das sementes de soja com fludioxonil+mefenoxan e thiabendazole+thiram é eficiente no controle de Colletotrichum truncatum e melhora o desempenho fisiológico das sementes. O desempenho das sementes de soja e o crescimento das plantas são reduzidos quando as sementes são tratadas com tiofanato metílico. A peliculização não afeta o potencial fisiológico e a qualidade sanitária das sementes de soja.

The sanitary and physiological qualities of soybean seeds are determining factors for the establishment of appropriate stands. This research aimed to evaluate the soybean seed performance and plants growth after seed inoculation with Colletotrichum truncatum and fungicide treatment by film-coating. The seeds were inoculated whit C. truncatum by water restriction technique and then treated with fungicides and polymer. The used treatments were carbendazin, fludioxonil+mefenoxan, thiabendazole+thiram, thiophanate methyl, caboxin+thiram and untreated seeds. The seeds were treated with and whitout polymer. Seed germination, cold test, seedling emergence and seed health test (blotter test) were evaluated. Plants grown in pots were evaluated using length of aerial parts, dry matter of roots and aerial parts. The best control of C. truncatum was obtained when the seeds were treated with fludioxonil+mefenoxan and thiabendazole+thiram. These treatments also contributed to improve the physiological performance of the seeds. The soybean seeds vigour and the plants growth were reduced when the seeds are treated whit methyl thiophanate. The film-coating do not affect the physiological potential and the soybean seed health.

Comportamento de progênies F4 obtidas por cruzamentos de 'Icatu' com 'Catimor' / Behavior of F4 progenies obtained from crossing of Icatu with Catimor

Conduziu-se este trabalho com o objetivo de avaliar progênies de cafeeiro resultantes do cruzamento entre 'Icatu' x 'Catimor', quanto à produtividade e vigor vegetativo e selecionar progênies superiores para avançar no programa de melhoramento dessa população. O delineamento utilizado foi em blocos casualizados com quatro repetições, 30 tratamentos (29 progênies do cruzamento mais a cultivar Rubi MG 1192, utilizada como testemunha). Para análise de variância dos dados adotou-se o esquema de parcela subdividida no tempo. Foram analisados a produção em sacas beneficiadas.ha-1 de seis colheitas 2001/2002 a 2006/2007 e o vigor vegetativo avaliado após a colheita 2006/2007. Os resultados obtidos permitem verificar a presença da variabilidade genética para produção entre as progênies avaliadas, fato confirmado pela alta estimativa da maioria das progênies estudadas, demonstraram que é possível selecionar progênies superiores na população estudada.

The objective of this research was to evaluate coffee progenies resulted from the crossing of 'Icatu' with 'Catimor' in relation to their production and plant vigor and to select higher quality progenies to advance the breeding program of this population. For this purpose, a randomized complete block design was carried out with four replications and for the analysis of variance, the Split plot temporal arrangement was adopted. Twenty nine progenies plus the Rubi MG 1192 cultivar, used as a control, were evaluated. The yield of beans in bags.ha-1 of six harvests from 2001/2002 to 2006/2007 was evaluated and the plant vigor after the harvest was assessed. The results indicated that the evaluated progenies showed variability mainly for grain yield confirmed by heritability. This condition associated to high bean yields, which reached 62.0 bags.ha-1 and high plant vigor, showed the possibility of selecting outstanding progenies in the studied population.

Superação da dormência e avaliação da qualidade fisiológica de sementes de Sesbania virgata / Dormancy break and evaluation of physiological quality of Sesbania virgata seeds

A avaliação da qualidade fisiológica de lotes de sementes de Sesbania virgata é dificultada pela dormência inerente à espécie, bem como pela inadequação metodológica de testes disponíveis. Para desenvolver procedimentos adequados à avaliação da qualidade das sementes de S. virgata, foram avaliados métodos tanto para quebra de dormência como para realização do teste de tetrazólio. Em uma primeira fase, as sementes de cinco lotes foram submetidas a tratamentos para quebra de dormência: lixa, ácido e corte do tegumento, previamente ao teste de germinação. Para caracterização dos lotes e adequação da metodologia do teste de tetrazólio, na segunda fase, as sementes foram lixadas na região oposta ao eixo embrionário, e submetidas aos seguintes testes: tetrazólio, germinação, velocidade de emergência, peso de matéria fresca e de matéria seca de plântulas. Foram utilizados dois métodos de pré-condicionamento: embebição em papel por 18 h a 30 ºC e imersão em água por 12 h a 30 ºC e três períodos (uma, duas e três horas) de imersão em solução de tetrazólio 0,5%. Na análise do perfil dos lotes de S. virgata foram detectadas variações na qualidade fisiológica pelos resultados dos testes de vigor e germinação. O método de escarificação com lixa possibilitou a quebra de dormência das sementes de S. virgata,e o pré-condicionamento das sementes em papel com embebição em solução de tetrazólio 0,5% por duas horas é um procedimento adequado para avaliação da viabilidade das sementes.

The evaluation of Sesbania virgata seed physiological quality is hampered by its intrinsic seed dormancy and inadequate methodologies among available tests. To develop an adequate procedure to evaluate S. virgata seed quality, methods for dormancy breaking and tetrazolium test accomplishment were evaluated. In a first stage, seeds from five lots were submitted to dormancy breaking methods: sandpaper, acid and tegument cuts, followed by germination tests. To characterize lots and adapt a tetrazolium-test, in a second stage, seeds were sanded in the area opposite to the embryonic axis and submitted to the following tests: tetrazolium, germination, vigor index, fresh and dry weight. Two preconditioning conditions (soaked paper for 18 h at 30 ºC and immersion in water for 12 h at 30 ºC) and three immersion timespan (one, two and three hours) in tetrazolium solution 0.5% were used. In the S. virgata lot profile analysis, variations were detected in its physiological quality according to vigor index and germination results. Scarification method with sandpaper better broke S. virgata seed dormancy, and preconditioning seeds in soaked paper followed by immersion in tetrazolium solution for two hours was the appropriate procedure to assess seed viability.

Testes de envelhecimento acelerado e deterioração controlada na avaliação do vigor de aquênios de girassol / Accelerated aging and controlled deterioration seeds vigour tests for sunflower

Os testes de vigor têm sido desenvolvidos para diferenciar os lotes de sementes devido às limitações impostas pelo teste de germinação. O objetivo do trabalho foi analisar a eficiência dos testes de envelhecimento acelerado e deterioração controlada na avaliação do vigor de lotes de aquênios de girassol. Para tanto, cinco lotes de aquênios (sementes com o pericarpo) de girassol da cultivar "Catissol 01" foram submetidos à determinação do grau de umidade e à avaliação da qualidade fisiológica, empregando os testes de germinação e vigor (primeira contagem, teste de frio, condutividade elétrica, emergência de plântulas, índice de velocidade de emergência, envelhecimento acelerado pelos sistemas tradicional e com solução saturada de NaCl a 42°C por 48, 72, 96 horas e deterioração controlada com teor inicial de água de 15, 20, 25 por cento por 48, 72, 96 horas a 42°C). Os resultados permitiram concluir que o teste de envelhecimento acelerado com solução saturada de NaCl por 96 horas foi eficiente para classificar os lotes de aquênios de girassol. As combinações de 20 por cento de água nos aquênios por 72 horas de exposição e de 25 por cento de água nos aquênios por 48 e 72 horas de exposição permitem classificar os lotes de aquênios de girassol.

The vigour tests were developed to detect differences of seeds lots owing to limitations the germination test. This study was conducted to compare different procedures of the accelerated aging and controlled deterioration tests to evaluate sunflowers seed vigour. Five lots of sunflower achenes (seeds with pericarp) cv. Catissol 01 were submitted to the water content test and to the evaluation of physiological quality using by germination and vigour test (first count, cold test, electrical conductivity, seedling emergence and speed of emergence index, accelerated aging with tradicional system and satured solution of NaCl, at 42°C for 48, 72, 96 hours and controlled deterioration with 15, 20, 25 percent water content for 48, 72, 96 hours at 42°C). The results showed that the accelerated aging test with use of satured solution of NaCl for 96 hours was efficient to classify the sunflowers achenes lots. The combinations of 20 percent water in the achenes for 72 hours and the combination of 25 percent water in the achenes for 48 and 72 hours was efficient to classify the sunflowers achenes lots.