GENETICS OF SOME AGRONOMIC AND YIELD TRAITS IN RICE (Oryza sativa L.)
GENETICS OF SOME AGRONOMIC AND YIELD TRAITS IN RICE (Oryza sativa L.)
No Thumbnail Available
Date
2012-03
Authors
ISMAILA, ABUBAKAR
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Six rice genotypes (FARO20 and FARO52 as female parents and FARO31, FARO39,
FARO45 and FARO46 males) were crossed in a line x tester mating fashion to develop eight
(8) F1 hybrids. The parents along with the F1 population were evaluated during the off season
in 2010 at the screen house of the Institute for Agricultural Research (I.A.R), Samaru in a
completely randomized design with three replicates to obtain information on estimates of
genetic variations, combining ability, heterosis and heritability. Data were taken on seedling
vigour, plant height, number of tillers, days to 50% flowering, panicle length, panicle
weight, yield per plant and 1000grain-weight. Results from analysis of variance showed
highly significant differences among the genotypes for all the traits. This is an indication of
the presence of considerable amount of genetic variability in the materials, which could be
used to initiate selection for population improvement. Phenotypic Coefficient of variation
(PCV) values were slightly greater than Genotypic Coefficient of variation (GCV). However
maximum GCV were obtained for yield per plant (28.94%), panicle weight (21.22%), 1000-
grain weight (19.43%) and number of tillers (17.74%). Estimates of variance due to GCA
and SCA and their ratios revealed preponderance of non-additive gene action for all
characters except for days to 50% flowering. Positive GCA and SCA effects were observed
among the lines and testers for yield per plant and other agronomic characters studied.
Significant heterosis were revealed for most of the characters studied. Among the hybrids,
FARO20 x FARO45 recorded the highest significant Positive heterosis for mid (115.27%)
and high parent (80.06%) heterosis for yield per plant while FARO20 x FARO39 revealed
negative heterosis for plant height and days to 50% flowering which is highly desirable as it
confers resistance to lodging and early maturity. Broad sense heritability estimates were
high for all the traits coupled with high genetic advance for yield per plant, 1000grainweight,
panicle weight, number of tillers and plant height, while the lowest genetic advance
was observed in panicle length. Correlation studies revealed that genotypic correlations were
generally higher than the phenotypic correlations for most of the traits. However, yield per
plant correlate positively and significantly with seedling vigour, plant height and panicle
weight at genotypic level
Description
A thesis Submitted to the School of Postgraduate Studies,
Ahmadu Bello University, Zaria
In Partial Fulfillment for the Award of Master of Science in Plant Breeding
DEPARTMENT OF PLANT SCIENCE
FACULTY OF AGRICULTURE
AHMADU BELLO UNIVERSITY
ZARIA
MARCH, 2012
Keywords
GENETICS,, AGRONOMIC,, YIELD,, Oryza sativa L