Heterosis and heritability in crosses among Asian and Ethiopian parents of hot pepper genotypes |
| |
| Authors: | Fekadu Marame Lemma Dessalegne Chemeda Fininsa Roland Sigvald |
| |
| Institution: | (1) Melkasa Agricultural Research Center, Ethiopian Institute of Agricultural Research, P.O. Box 2500, Adama, Ethiopia;(2) Department of Plant Sciences, Haramaya University, P.O. Box 138, Dire-Dawa, Ethiopia;(3) Department of Ecology, Swedish University of Agricultural Sciences, P.O. Box 7044, 750 07 Uppsala, Sweden |
| |
| Abstract: | Hot pepper is the most important worldwide grown and consumed spice and vegetable crop. Though hybrid breeding has been proposed
for genetic improvement in the crop, but there is lack of information on heterosis in crosses among crop genotypes in Ethiopia.
Twelve genotypes (nine Asian and three Ethiopian parents) of hot pepper were crossed in 2003 cropping season in a half-diallel
fashion to fit Griffing’s fixed effect model analysis. An open field experiment was conducted in 2004/2005 to investigate
heterosis for fourteen traits in 66 F1 hybrids grown together with their 12 selfed parents. Highly significant genotypic differences were observed for all the traits
except for leaf area. Variance component due to specific combining ability (dominance) were larger than that due to general
combining ability (additive) for each of the studied traits with few exceptions. Broad sense heritability (H
b2) for fruit traits were more than 60% and with wide gap from narrow sense heritability (h
n2) for most of the important traits like number of fruit per plant (H
b2 = 88.3% and h
n2 = 46.0%), days to maturity (H
b2 = 87.2% and h
n2 = 23.1%) and dry fruit yield per plant (H
b2 = 72.6% and h
n2 = 14.6%). Maximum heterosis over mid-parent and better-parent, and economic superiority of hybrid over standard check were
recorded, respectively for dry fruit yield per plant (163.8, 161.8 and 92.1%), number of fruits per plant (104.4, 79.6 and
136.4%) and days to maturity (−29.8, −31.5 and −23.6%). These observations suggested a possibility of utilizing dominance
genetic potentiality available in diverse genotypes of the crop by heterosis breeding for improving hot pepper to the extent
of better economic return compared to the current commercial cultivar under production in the country. Low narrow sense versus
very high broad sense heritability for days to maturity and dry fruit yield per plant could be a sign for achievability of
earliness and high fruit yield using heterosis in hot pepper. The maximum heterobeltiosis were recorded either from F1s obtained from Ethiopian and Asian crosses or from within Asian crosses, suggesting the possibility of maximizing heterosis
by considering genetically diverse parental genotypes. The manifestation of highest heterosis in hybrids from among Asian
lines indicated existence of genetic diversity among Asian genotypes and the potentiality for improvement of hot pepper using
genotypes from different regions of the world along with elite inbred lines from local cultivars. |
| |
| Keywords: | Capsicum annuum F1 hybrids Gene action Genetic diversity Heterosis breeding |
| 本文献已被 SpringerLink 等数据库收录！ |
|
