Genetic control of agronomically important traits of pepper fruits analyzed by Hayman�s partial diallel cross scheme
Author(s): A.R. Schuelter, G.M. Pereira, A.T. Amaral J�ºnior, V.W.D. Casali, C.A. Scapim, W.S. Barros and F.L. Finger
Pepper species of the genus Capsicum have been cultivated over centuries, producing both pungent and sweet fruit; the pungency is caused by alkaloids called capsaicinoids. Among the five cultivated species, Capsicum chinense is one of the most popular, being native to the Amazon basin. This species is characterized by a wide variety of fruit sizes, shapes and colors, with different capsaicinoid content. In addition, fruits are rich in vitamins A and C. Despite the importance of this plant as a spice and its medicinal uses, research on its genetic variability and potential for breeding programs is still incipient. We investigated the genetic control of some traits through diallel analysis with the objective of introgressing these traits into cultivated varieties.
For the diallel analysis, the progeny of crosses between peppers with
pungent and sweet fruits, together with the parents, were grown in pots
under greenhouse conditions. The fruits were harvested and analyzed
for the traits total fresh fruit mass, total dry fruit mass, percentage dry
matter, total soluble solids, vitamin C content, fruit pungency, and
number of seeds per fruit. Genetic variability was detected for all traits.
In the diallel analysis, the additive-dominant model was considered to
be adequate for total fresh fruit mass, percentage dry matter, total soluble
solids, and vitamin C content. Additive genetic effects and dominance
were found for all traits; consequently, breeding for improvement of
these fruit traits would be viable.