Abstract The germination potential must be considered in the selection of passion fruit genotypes, since vigorous seeds originate seedlings with a higher growth rate, resulting in superior plants with high agronomic performance. This study proposes to estimate genetic parameters and selection gain for seed traits of full-sib families (FSF) of passion fruit under recurrent selection for resistance to the cowpea aphid-borne mosaic virus (CABMV). Physical and physiological seed traits of 86 FSF were evaluated; genetic parameters, genotypic correlations between traits and genetic gains were estimated using four selection indices. There were significant differences and genetic variability between families and positive genetic correlations between variables. The best distribution of genetic gains was obtained by the Mulamba and Mock index, using the heritability coefficient and arbitrary weights. This index selected the best 26 families in terms of seed characteristics to compose the second cycle of recurrent selection for resistance to CABMV.

ABSTRACT Investigating the physiological potential of seeds and genetic divergence between families is essential to identify promising materials for the generation of improved populations. This study was undertaken to examine the germination potential and estimate genetic divergence between Passiflora full-sib families (FSFs) based on physical and physiological seed traits. The experiment was consisted of 86 FSFs from the first cycle of recurrent selection for resistance to the cowpea aphid-borne mosaic virus. Seeds were evaluated for 19 physical and physiological traits. Dissimilarity estimates were obtained by generalized Mahalanobis distance, and the method unweighted pair group method with arithmetic mean was employed for cluster formation. The FSFs showed high germination potential and seed vigor, with mean of 92.4%, 5.68 e 5.81 cm for germination, germination speed index (GSI) and shoot length of seedlings, respectively. Cluster analysis resulted in four groups formed, being Group I composed by 68 FSF more the control Passiflora edulis. The trait 1,000-seed weight (TSW) was the trait that most contributed to explaining the dissimilarity between families, with 31.9%. The trait GSI (physiological), TSW (physical), as well as traits provided by the GroundEye® system (CIELab-b, hue, and circumference of seeds), were efficient in determining genetic divergence detected between the families of passion fruit. These traits can be taken as a basis in the selection of genotypes with higher physiological seed quality.

ABSTRACT The present study had as the main objective the documentation and characterization of the different phenological stages, as well as the definition of the thermal requirements, of the atemoya tree for two agronomic seasons. From shoot development to senescence and beginning of the rest period eight main stages were described (shoot development, leaf development, shoot/bud growth, inflorescence appearance, flowering, fruit development, fruit maturity and senescence and the beginning of the rest period). The number of days and the thermal requirements for completing each phenological stage were different between the two agronomic seasons of the atemoya. The first and second agronomic season presented a period of 217 and 206 days, with thermal requirements of 2469 and 2302 degree days, respectively.

RESUMO: Este trabalho teve como objetivo avaliar a eficiência da aplicação de diferentes doses de uniconazole (UCZ) em mangueira 'Palmer' no comportamento vegetativo, reprodutivo e nas características físicas, químicas e produtivas dos frutos durante o período de entressafra na região Norte de Minas Gerais. O delineamento experimental foi em blocos ao acaso, testando-se as doses 0,0; 1,0; 1,0+1,0 (2,0) após 30 dias; 1,0+1,0+1,0 (3,0) parcelado a cada 30 dias; 1,0+1,0+2,0 (4,0) parcelado a cada 30 dias, em g, do ingrediente ativo (i.a.) de UCZ por planta, aplicado via foliar. Verificou-se que todos os tratamentos com uso de uniconazole reduziram o alongamento dos ramos da mangueira 'Palmer', quando comparada com a testemunha, apresentando uma redução média de 81,6%, no entanto, apenas a aplicação de 1,0+1,0+2,0g i.a. UCZ/planta parcelado a cada 30 dias foi eficiente em promover a floração no período da entressafra, possibilitando um incremento médio de 167% no número de frutos por planta e de 9,78t ha-1 na produtividade.

ABSTRACT: The objective of this study was to evaluate the effects of different doses of uniconazole (UCZ) on 'Palmer' mango vegetative and reproductive response and on fruit physical, chemical, and productive characteristics during the off-season in northern Minas Gerais, Brazil. The experiment followed a randomized block design. UCZ was tested at the following doses applied to leaves and expressed in g of UCZ active ingredient (a.i.) per tree: 0.0, 1.0, and 1.0+1.0 (2.0) after 30 days; 1.0+1.0+1.0 (3.0) subdivided into 30-day intervals; and 1.0+1.0+2.0 (4.0) subdivided into 30-day intervals. All of the UCZ treatments reduced branch elongation in the 'Palmer' mango trees, leading to a mean reduction of 81.6% compared to the control. However, the UCZ application of 1.0+1.0+2.0g a.i. per tree subdivided into 30-day intervals was efficient in promoting flowering during the off-season, enabling a 167% mean increase in the number of fruit per tree and a 9.78t ha-1 mean increase in productivity.