Studies on genetic variability of yield components and their relative contribution to grain yield in rice (Oryza sativa L.)
Loading...
Date
2005
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
CCSHAU
Abstract
In the present investigation, Forty three genotypes of different
maturity groups of non scented rice and five scented dwarf rice
genotypes selected to carry out present study were planted in four
different environments at RRS Kaul with four different doses of fertilizers
viz., E1 : 120N, 60 P2O5, 60 K2O; E2: 120N, 0 P2O5, 0 K2O; E3: 120N,
60 P2O5, 0 K2O and E4: 120N, 0 P2O5, 60 K2O. These genotypes were
transplanted in a Randomized Block Design with four replications with a
spacing of 20cm x 15 cm. Five randomly selected plants from the
population of each genotypes were taken for the recording of the data.
Significant differences existed among the genotypes for all the
characters studied under the four environments which indicated the
presence of adequate variability among the genotypes. The genetic
expression in most of the cases changed with the change in the
environment. On the basis of mean performance for different traits, E1
appeared to be better environment. Mean performance in E1 and E2
clearly indicated the importance of balanced use of fertilizers for the
expression of different traits. The E2 had lowering effect on the
expression of h2, GA, GCV and PCV.
In general the magnitude of genotypic correlation was slightly
higher than the phenotypic correlation for all the characters studied
indicating strong inherent association among the characters. The path
coefficient analysis showed that no. of tillers/plant had the highest
positive direct effect on grain yield except in environment E4 where the
grain length had the highest positive direct effect on grain yield. The
traits L/B ratio showed the highest negative direct effect in all the
environments. The indirect effect did not show any specific trend.