Lucas da Silva Domingues

Comparison among direct, indirect and index selections on agronomic traits and nutritional quality traits in common bean.

BACKGROUND Selection indices are linear combinations that allow the selection of several characters simultaneously. The objective of this study was to verify the efficiency of direct selection, indirect selection and selection indices in the identification of higher inbred common bean lines for grain yield, morphological, phenological and nutritional traits. RESULTS There is genetic variability for grain yield, lodging, general adaptation note, cycle, insertion of the first pod, calcium and iron concentrations in the seeds. Moderate phenotypic correlation coefficients were observed between grain yield and general adaptation note (r = -0.57) and cycle (r = -0.57). When direct selection was performed for grain yield, the insertion of the first pod, calcium and iron concentrations showed negative indirect selection gains. The classic index showed that the distribution of gains has become more balanced: grain yield (39.05%), calcium (8.29%) and iron concentration (1.64%). CONCLUSION Direct selection and indirect selection are not efficient in the simultaneous selection of agronomic traits and nutritional quality in common bean. The classical, base and multiplicative indexes provide responses of gain balanced among traits and superior genetic progress in the selection of inbred common bean lines, and have a high coincidence between the lines selected.

Desempenho agronômico e qualidade de cozimento de linhagens de feijão de grãos especiais

RESUMO - O cultivo de feijao de graos especiais ainda e restrito no Brasil. Portanto, os objetivos foram: i) avaliar os efeitos da interacao linhagem x ambiente nos caracteres que controlam o desempenho agronomico e o tempo de cozimento em linhagens de feijao de graos especiais e ii) identificar linhagens de alto desempenho agronomico e de reduzido tempo de cozimento. Para isso, 29 linhagens de feijao de graos especiais foram avaliadas em diferentes locais, anos e epocas de cultivo. Interacao linhagem x ambiente significativa foi observada para todos os caracteres avaliados. As linhagens Light Red Kidney, Red Kanner, Montcalm, Chinock e BRS Radiante apresentaram produtividade de graos similar nos quatro ambientes. As linhagens avaliadas possuem ciclo semi-precoce ou precoce e tem caracteristicas morfologicas desejaveis. Os seguintes valores de claridade de tegumento de graos foram obtidos para feijao branco (72,85 a 82,25), rajado (33,06 a 62,57), vermelho (24,51 a 43,69), verde (57,01 a 62,36) e rosa (49,95 a 55,60). O tempo de cozimento variou de 14 min e 38 seg a 36 min e 21 seg. As linhagens de feijao de graos especiais de tegumento vermelho (Light Red Kidney, Red Kanner, Montcalm e Chinock) e de tegumento rajado (BRS Radiante) apresentam alto desempenho agronomico e reduzido tempo de cozimento nas condicoes avaliadas. Palavras-chave: Phaseolus vulgaris L.. Interacao genotipo x ambiente. Caracteres morfologicos. Feijao-qualidade. Feijaocozimento.

Seleção de linhagens de feijão com alto desempenho agronômico e elevadas concentrações de cálcio e ferro

The objective of this work was to evaluate the genetic variability of common bean lines for cycle, weight of 100 grains, grain yield, cooking time, and grain calcium and iron concentrations. Twenty-four common bean lines were evaluated in two crop cycles (2010 and 2011). The ¯Z index was used for the selection of superior lines for most of the traits. The DF 06-19, DF 06-03, DF 06-17, DF 06-20, DF 06-11, DF 06-14, DF 06-01, DF 06-08, DF 06-22, and DF 06-04 lines showed high grain yield. All lines were of semi-early cycle and of fast cooking. The DF 06-08 and DF 06-23 lines showed high calcium concentration in grains (>1.4 g kg-1 dry matter - DM), and the DF 06-09, DF 06-03, DF 06-04, and DF 06-06 lines presented high iron concentration in grains (>0.95 g kg-1 DM) in the two crop cycles. The DF 06-09 and DF 06-03 carioca lines present high agronomic performance and high iron concentration in grains. The DF 06-17 and DF 06-08 black lines present high agronomic performance and high calcium concentration in grains. The selection of the DF 06-09, DF 06-03, DF 06-17, and DF 06-08 lines is recommended.

Efeito do tratamento de sementes com fungicidas e acibenzolar-S-methyl no controle da ferrugem asiática e crescimento de plântulas em cultivares de soja

ABSTRACT The influence of acibenzolar-S-methyl (ASM) and fungicidesapplied as seed treatment on Asian rust control as well as on growthof soybean seedlings were evaluated in a completely randomizedexperiment with three replications, using the ‘Agiara’, ‘M-soy 8000’and ‘M-soy 8080’ soybean cultivars. The treatments were three dosesof ASM (0,05; 0,1 and 0,2 g of a.i. for kg of seeds), ASM (in the doseof 0,1 g of a.i. for kg of seeds) combined to the fungicides flutriafol,pyraclostrobin and azoxystrobin, and the isolated application of theseas well as a control treated with water. The results showed reductionof Area Under Progress Rust Curve (AUPRC) with the increase of thedose of ASM in the three cultivars of soybean. The isolated use of Debona, D., Figueiro, G.G., Corte, G.D., Navarini, L., Domingues, L.da S., Balardin, R.S., Effect of seed treatment with fungicides andacibenzolar-S-methyl in soybean cultivars on Asian rust control and seedlings growth. Summa Phytopathologica, v.35, n.1, p.26-31, 2009

Atividade inseticida de meliáceas sobre Diabrotica speciosa (Col., Chrysomelidae)

Diabrotica speciosa is a polyphagous insect-pest and its control demands a great deal of insecticides applications. The use of extracts from Meliaceae family plants, with insecticidal activity, appears as a promising control alternative. The present work aimed to evaluate the control action of aqueous extract from Melia azedarach var. azedarach (chinaberry) - unripe fruits, petioles with stalk, leaflets and barks - at 10% (p/v) each one, compared with NIM-I-GO at 10mL L-1 (emulsified commercial oil of neem) and DECIS 25CE at 0.3mL L-1, as a standard treatment, over adult insects of D. speciosa on cucumber (Cucumis sativus) and string beans (Phaseolus vulgaris) cultivated in greenhouse. It was evaluated as well the height of plants, after the beginning of the harvest, and the production. Extracts of unripe fruits, leaflets and petioles with stalk of chinaberry are flattering in the control of D. speciosa in cultures of cucumber, and only unripe fruits in string beans. Therefore, these extracts can be used as alternatives in control of this chrysomelid. The use of these extracts did not result in significant change in stature and the production of the plants, when compared with the control.

Selection of common bean lines for calcium use efficiency

The study of the calcium use efficiency in common bean is unprecedented. Therefore, the objectives of this work were to evaluate the genetic variability of common bean lines for plant growth and grain yield characters, the calcium accumulation in different plant tissues at low and high calcium availabilities, and to select common bean lines with high calcium use efficiency and responsive to the calcium application by different indices. Twelve common bean lines were supplied with a nutrient solution at low (1.10 mmol L-1) and high (3.85 mmol L-1) calcium concentration and were evaluated. The L 15 line reached the higher values of dry mass of shoot, number of pods and grains per plant, number of grains per pod and grain yield at the low calcium concentration. Calcium accumulation in tissues was, on average, higher in leaves, followed by stems, pods and grains. The L 175 and L 159 lines have higher calcium concentration in grains (> 1.1 g kg-1 MS), regardless of the calcium concentration supplied to plants. The L15 line is efficient in calcium use. The L 221 and L 159 lines are responsive to the calcium application in the rooting medium.