Jaison Pereira de Oliveira

Dry Matter, Grain Yield, and Yield Components of Dry Bean as Influenced by Nitrogen Fertilization and Rhizobia

Dry bean is an important legume crop for a large portion of the worlds population. Nitrogen (N) is one of the most yield-limiting nutrients in all dry bean–producing regions of the world. A greenhouse experiment was conducted to evaluate responses of 15 dry bean genotypes to N fertilization with and without rhizobial inoculation grown on a lowland soil locally known as Varzea. Nitrogen treatments were (i) 0 mg N kg−1 (control or N0), (ii) 0 mg N kg−1 + inoculation with rhizobial strains (N1), (iii) inoculation with rhizobial strains + 50 mg N kg−1 (N2), and (vi) 200 mg N kg−1 (N3). Shoot dry weight, grain yield, yield components, maximum root length, and root dry weight were significantly affected by N fertilization, rhizobial inoculation, and genotype treatments. The N × genotypes interactions were significant for shoot dry weight, grain yield, number of pods per plant, number of grain per pod, 100-grain weight, grain harvest index (GHI), and maximum root length and root dry weight. These significant interactions indicate that genotypes performance varied with varying N rates and inoculation treatments. Maximum grain yield was produced at 200 mg N kg−1 treatment. Inoculation with rhizobial strains improved grain yield but did not reach the level of 200 mg N kg−1 applied with chemical fertilizer. Based on grain yield efficiency index, genotypes were classified as efficient, moderately efficient, and inefficient in N-use efficiency. Overall, the most efficient genotypes were BRS Pontal, Diamante Negro, BRS Grafite, BRS Requinte, and BRS 9435 Cometa, and inefficient genotypes were BRSMG Talisma and Aporé.

Toxicity of neem oil to Bemisia tabaci biotype B nymphs reared on dry bean.

O objetivo deste trabalho foi determinar o estagio ninfal de Bemisia tabaci biotipo B mais suscetivel ao oleo de nim (Azadirachta indica A. Juss.) aplicado em feijoeiro (Phaseolus vulgaris L.), em casa telada. Foram avaliados o tempo letal (TL) e concentracao letal (CL) do oleo comercial de sementes de nim Dalneem. Para CL, concentracoes de 0, 0,1, 0,25, 0,5, 1 e 2% do produto foram pulverizadas diretamente sobre as ninfas em cada instar. Para TL, o produto foi avaliado a 0, 0,5 e 1% de oleo de nim em cada instar. Ninfas vivas e mortas foram contadas cinco dias apos a pulverizacao para CL e diariamente para TL durante seis dias. Para o quarto instar, a CL50 foi de 0,56% de oleo de nim. Considerando todos os instares, CL50 e CL95 foram estimadas em 0,32 e 2,78% de oleo de nim, respectivamente. Os TL50 para 1% de nim foram estimados em 2,46, 4,45, 3,02 e 6,98 dias para o primeiro, segundo, terceiro e quarto instares, respectivamente. Os TL50 estimados para 0,5 e 1% de oleo de nim foram de cinco e quatro dias, respectivamente, considerando todos os instares. No sexto dia, foi observada mortalidade superior a 80% para o primeiro, segundo e terceiro instares a 1% de oleo de nim. Os tres primeiros instares foram mais suscetiveis ao oleo de nim que o quarto instar.

Yield and Yield Components of Dry Bean Genotypes as Influenced by Phosphorus Fertilization

Dry bean is an important legume for South American population, and phosphorus (P) deficiency is the most yield-limiting nutrient for crop production in South American soils. A greenhouse experiment was conducted with the objective of evaluating influence of P fertilization on grain yield and yield components of 30 dry bean genotypes. The P levels used were 0 mg P kg−1 (natural level of the soil) and 200 mg P kg−1 applied with triple superphosphate fertilizer. Yield and yield components were significantly influenced with P as well as genotype treatments. The P × genotype interactions were significant for yield as well as yield components, indicating different responses of genotypes at two P levels. Root dry weight and maximum root length were also significantly increased with the addition of P fertilization. There were also significant differences among the genotypes in the growth of root system. Based on grain yield efficiency index (GYEI), genotypes were classified as P efficient, moderately efficient, and inefficient. Among 30 genotypes, 17 were classified as efficient, 12 were classified as moderately efficient, and 1 was classified as inefficient. Yield components such as pods per plant and seeds per pod were having significant positive association with grain yield. In addition, grain harvest index (GHI) was also having significant linear association with grain yield. Hence, it is possible to improve grain yield of dry bean in Brazilian Oxisol with the addition of adequate rate of P fertilization as well as use of P-efficient genotypes.

Genótipos de feijoeiro comum sob deficiência hídrica

The objective of the work was to study the adaptation of common bean genotypes to water deficit. Fortynine genotypes were evaluated in a randomized block design, with three replications, in experiments with and without water deficit, conducted at the Experimental Station of SEAGRO, in Porangatu-GO during 2006 and 2007. Multivariable analysis was applied using de Ward’s method and the genotypes were divided in four groups based on the average grain yield of each water treatment, during the two years of the experimentation. The genotypes BRA 130583 CIAT G 6490 and FT 84 - 292 were classified as the most productive in the absence or under water deficit, while the genotypes BRA 283983 CIAT G 6492, BRA 129721 CIAT G 6896, and G 983 were classified as productive in the absence of water deficit, but they were more sensitive to this stress. It was also verified that the number of pods per plant was the most sensitive agronomic component to water deficit in common bean.

Heterosis performance in industrial and yield components of sweet corn

Heterosis and its components were evaluated in a diallel crossing system of sweet corn. In the 38 treatments, eigth parents, 28 hybrids and two controls were used, arranged in a randomized block design with three replications.The diallel analysis followed the methodology of Gardner and Eberhart (1966). The following traits were evaluated: male and female flowering, plant and ear height, ear index (number of ears/number of plants), oBrix, total ear weight, standard ear weight, industrial yield and total sugar content. There was genetic variability among genotypes, with significant differences except for the traits ear index, industrial yield and oBrix.Heterosis was found for most traits. The mean heterosis of hybrids compared with the parents was positive for most traits. There was a contribution of additive and dominance effects.The contribution of dominant genes was greatest to flowering, plant and ear height and standard ear weight.

Infrared thermometry for drought phenotyping of inter and intra specific upland rice lines

Propos-se avaliar, no presente estudo, a tecnica da termometria ao infravermelho na caracterizacao de linhagens interespecificas (Oryza glaberrima x Oryza sativa cv Caiapo) e intraespecificas de arroz para tolerância a seca. O experimento, conduzido em Porangatu, GO, foi submetido a condicoes adequadas de umidade no solo ate 30 dias apos a emergencia, quando entao foi implantado um tratamento com deficiencia hidrica moderada (aproximadamente 50% da irrigacao aplicada em uma parcela testemunha, com condicoes adequadas de umidade no solo). Verificou-se que as linhagens mais produtivas em condicoes de deficiencia hidrica apresentaram plantas mais altas, com paniculas mais densas e com graos mais bem formados, com menor esterilidade de espiguetas. Observou-se, tambem, que a temperatura das folhas se correlacionou positivamente com a esterilidade de espiguetas e negativamente com a massa de 100 graos, altura das plantas, fertilidade de perfilhos e produtividade. Exceto a fertilidade de perfilhos, os demais componentes se correlacionaram com a produtividade de graos, sendo que com a esterilidade de espiguetas a correlacao foi negativa. Concluiu-se que a O. glaberrima confere, as suas progenies, maior rusticidade a deficiencia hidrica e que a termometria ao infravermelho e uma tecnica auxiliar importante na fenotipagem para tolerância a seca.

In-depth genome characterization of a Brazilian common bean core collection using DArTseq high-density SNP genotyping

BackgroundCommon bean is a legume of social and nutritional importance as a food crop, cultivated worldwide especially in developing countries, accounting for an important source of income for small farmers. The availability of the complete sequences of the two common bean genomes has dramatically accelerated and has enabled new experimental strategies to be applied for genetic research. DArTseq has been widely used as a method of SNP genotyping allowing comprehensive genome coverage with genetic applications in common bean breeding programs.ResultsUsing this technology, 6286 SNPs (1 SNP/86.5 Kbp) were genotyped in genic (43.3%) and non-genic regions (56.7%). Genetic subdivision associated to the common bean gene pools (K = 2) and related to grain types (K = 3 and K = 5) were reported. A total of 83% and 91% of all SNPs were polymorphic within the Andean and Mesoamerican gene pools, respectively, and 26% were able to differentiate the gene pools. Genetic diversity analysis revealed an average HE of 0.442 for the whole collection, 0.102 for Andean and 0.168 for Mesoamerican gene pools (FST = 0.747 between gene pools), 0.440 for the group of cultivars and lines, and 0.448 for the group of landrace accessions (FST = 0.002 between cultivar/line and landrace groups). The SNP effects were predicted with predominance of impact on non-coding regions (77.8%). SNPs under selection were identified within gene pools comparing landrace and cultivar/line germplasm groups (Andean: 18; Mesoamerican: 69) and between the gene pools (59 SNPs), predominantly on chromosomes 1 and 9. The LD extension estimate corrected for population structure and relatedness (r2SV) was ~ 88 kbp, while for the Andean gene pool was ~ 395 kbp, and for the Mesoamerican was ~ 130 kbp.ConclusionsFor common bean, DArTseq provides an efficient and cost-effective strategy of generating SNPs for large-scale genome-wide studies. The DArTseq resulted in an operational panel of 560 polymorphic SNPs in linkage equilibrium, providing high genome coverage. This SNP set could be used in genotyping platforms with many applications, such as population genetics, phylogeny relation between common bean varieties and support to molecular breeding approaches.

BRS Notável: a medium-early-maturing, disease-resistant Carioca common bean cultivar with high yield potential

BRS Notavel is a common bean cultivar with carioca grain, suitable for cultivation in 20 Brazilian states. It is a medium- early-maturing cultivar, with an average yield of 2,261 kg ha -1 , 8.5% higher than the controls, a high yield potential (4,472 kg ha -1 ),

Common bean cultivar BRS Ametista with large Carioca grains and disease resistance

BRS Ametista is a common bean cultivar with Carioca grain and yields similar to cultivar Perola, but with larger grain size, resistance to anthracnose and Fusarium wilt. It is recommended for 18 states in all regions of Brazil and can be planted on over 95% of the area used for common bean in the country.

Controle genético do teor proteico nos grãos e de caracteres agronômicos em milho cultivado com diferentes níveis de adubação nitrogenada

O objetivo deste trabalho foi determinar o controle genetico do teor de proteina em graos e caracteres agronomicos milho (Zea mays) cultivado com diferentes niveis de adubacao nitrogenada. Foram avaliados nove genitores de milho e seus hibridos, em dialelo completo, com dois niveis de adubacao nitrogenada. Os caracteres avaliados foram: indice relativo de clorofila, altura de plantas, altura de espigas, producao de espigas, producao de graos, coloracao de graos, massa de cem graos, densidade de graos, teor de nitrogenio nas folhas e teor de proteina nos graos. A elevacao da adubacao nitrogenada promoveu aumento nos caracteres indice relativo de clorofila, altura de espigas e teor de proteinas nos graos. Apenas a variavel producao de graos apresentou controle genetico distinto nos diferentes niveis de nitrogenio. A analise dialelica mostrou significância dos efeitos dos genotipos sobre todos os caracteres, com excecao da producao de espigas e de graos, e foi possivel observar significância da heterose na maioria das variaveis. Para o teor de proteinas nos graos, nao houve significância da capacidade especifica de combinacao, e a capacidade geral de combinacao dos genotipos teve efeito mais importante na manifestacao desse carater.