The aim of this work was to estimate the general and specific combining ability of peppers by measuring fruit quality and yield traits. This experiment was carried out on the garden field from Universidade Federal de Viçosa (UFV), Minas Gerais State-Brazil. Eight lines of Capsicum baccatum belonging to the UFV Horticultural Germplasm Bank were chosen based on their broad genetic and phenotypical background variation and then they were crossed in a complete diallel way. The F 1 seeds of the 56 hybrids and eight parents were planted in the field in a randomized complete block design. The data were submitted to ANOVA and the means were grouped by Scott-Knott test (P B 0.01). Significant variation for fruit quality and yield components was observed among parents and F 1 generation. Analysis of variance for the combining ability showed that GCA effects exhibited significant difference and SCA effects of the crosses were significant, except for the height of first bifurcation. For almost all characters both additive and non-additive effects influenced the performance of hybrids.

The hot peppers belonging to the species C. baccatum are completely restricted to Latin America and comprise the most popular hot pepper consumed as fresh or as processed paprika in Andean countries. The objective of this study was to characterize the phenotypic diversity among 40 landrace accessions of C. baccatum based on morphological fruit quality traits and yield components, and to determine the correlation between these characters and their contribution for the genetic variability. The accessions were analyzed for 14 fruit and plant descriptors. Plants were arranged as randomized complete block with three replicates. Collected data were initially subjected to analysis of variance and if the F-test was significant at P B 0.01, the averages were grouped by Scott-Knott criteria. The heritability in a broad sense and phenotypic correlation were calculated. The phenotypic divergence and relative importance were estimated by multivariate analysis. Significant differences for all traits were observed by F-test (P B 0.01). The range of heritability values were between 83.2 and 99.1. The landraces were grouped in seven different clusters. Major fruit width, fruit weight and fruit dry matter were the only fruit traits with positive correlation with yield. Plant width, height, first bifurcation height and fruit set were positive correlated between them and with yield. Based on the data, the most divergent accessions were 4 and 24, which could result in higher heterotic effect in eventual hybridizations between them. The results of this study showed that spice and vegetable type specific varieties can be developed from C. baccatum.

In vitro chromosome doubling from hypocotyl segments of yellow passion fruit (Passiflora edulis Sims.) was carried out in the presence of either colchicine (0, 25, 250 and 1,250 lM) or oryzalin (0, 5, 15 and 30 lM). Murashige and Skoog (in Physiol Plant 15:473-497, 1962)(MS)-based regeneration medium containing 250 or 1,250 lM colchicine markedly affected explant development leading to browning and death of the hypocotyl segments. Oryzalin has similar effect to colchicine in inducing polyploidy. In vitro regenerated autotetraploid plants induced by 25 lM colchicine or 15 lM oryzalin were further acclimatized and cultivated in hydroponics system in greenhouse. Autotetraploids plants were more vigorous than the control diploids. The chromosome number of diploid plants was 2n = 2x = 18, whereas that found on autotetraploid plants were 2n = 4x = 36. The stomata sizes of the autotetraploids were significantly larger than those on the diploid counterparts, while the frequency of stomata was significantly reduced. Similarly, the chloroplast number of guard cells of autotetraploid plants increased significantly. Two albino plants (4%) were generated in medium with 25 lM colchicine, indicating phytotoxic effects. These plants are being grown to full maturity in order to test their potential to use in a breeding program.

ABSTRACT. The objective of this study was to determine the effects of the general and specific combining abilities (GCA and SCA, respectively) of 15 characteristics and to evaluate the most promising crosses and the reciprocal effect between the hybrids of six parents of the Capsicum annuum species. Six parents, belonging to the Horticultural Germplasm Bank of Centro de Ciências Agrárias of Universidade Federal da Paraíba, were crossed in complete diallel manner. The 30 hybrids generated and the parents were then analyzed in a completely randomized design with three replicates. The data were submitted to analysis of variance at 1% probability, and the means were grouped by the Scott-Knott test at 1% probability. The diallel analysis was performed according to the Griffing method, model I and fixed model. Both additive and non-additive effects influenced the hybrids' performance, as indicated by the GCA/SCA ratio. The nonadditive effects, epistasis and/or dominance, played a more important role than the additive effects in pedicel length, pericarp thickness, fresh matter, dry matter content, seed yield per fruit, fruit yield per plant, days to fructification, and total soluble solids. The GCA effects were more important than the SCA effects in the fruit weight, fruit length and diameter, placenta length, yield, vitamin C, and titratable acidity characteristics. The results found here clearly show that ornamental pepper varieties can be developed through hybridization in breeding programs with C. annuum.

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