The restricted maximum likelihood/best linear unbiased prediction (REML/BLUP) mixed model method has been used to study the effects of genotype by environment interaction (G x E) in various crops including cowpea. This work aimed to analyze the G x E interaction via mixed models to identify cowpea genotypes that meet high adaptability, stability and productivity of pods and green grains when grown under Mossoró, Rio Grande do Norte State conditions. Crop value and use were evaluated in two growing seasons, using randomized complete blocks design with 23 genotypes and four replications. The genetic parameters were estimated by the REML/BLUP procedure and selection was based on the harmonic mean of the relative performance of genetic values (HMRPGV). Agreement between the HMGV, relative performance of genotypic values (RPGV) and HMRPGV statistics, provided genotype discrimination. Furthermore, the HMRPGV results enabled the simultaneous selection of superior genotypes for productivity, adaptability and stability. For the productivities of pods and green grains, the most notable genotypes were the cultivars BRS Xiquexique and BRS Aracê, and the line MNC05-835B-15, which showed a high productivity of grains, adaptability and stability, and could be grown in the two growing seasons considered in the study.

The purpose of this study was to estimate the general and specific combining ability of melon hybrids to identify the best combinations. Six parents and their respective hybrids were evaluated in a complete randomized block design with three replications. The following traits were assessed: total number of fruits, average fruit weight, yield, longitudinal diameter, transversal diameter, flesh thickness, internal cavity size, flesh firmness, and soluble solids. The traits total fruit number, yield, flesh firmness and soluble solids content are controlled by additive and non-additive effects, while average fruit weight, longitudinal diameter, flesh thickness, internal cavity size are controlled by additive effects. The most appropriate crosses for breeding of Cantaloupe, Honey dew, Piel del sapo, Meloa and Amarelo melon are, respectively: Gold Mine x Hy Mark, AF-646 x AF-1749, Meloa x Rochedo and AF-646 x Rochedo.

A utilização de métodos de inoculação constitui uma medida estratégica no estudo de resistência das cucurbitáceas. O objetivo deste trabalho foi avaliar dois métodos de inoculação de Rhizoctonia solani e Macrophomina phaseolina em meloeiro, visando o estudo de resistência. O experimento foi conduzido em casa de vegetação na Universidade Federal Rural do Semiárido, em Mossoró-RN, Brasil. Foram avaliados 05 acessos: A-09, A-16, A-18, A-22 e A-33 para R. solani e A-09, A-16, A-24, MR-1 e 'Olimpic' para M. phaseolina. Foram estudados os métodos areno-orgânico e palito de dente. Utilizou-se o delineamento inteiramente casualizado, com 5 repetições. Os isolados utilizados foram: Me 242, Me 243, Me 244 de R. Solani e I-248, I-249 e I-250 de M. phaseolina. Os acessos de meloeiro foram avaliados quanto à severidade da doença por uma escala de nota de 1 a 5. O método do palito de dente foi o mais eficiente em discriminar acessos de melão resistentes e suscetíveis e os isolados de R. solani e M. phaseolina quanto à virulência.