Studies on the genetics of white rust and its association with DNA markers in Indian mustard (Brassica juncea L. Czern & Coss.)
Loading...
Date
2015
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
CCSHAU
Abstract
The present investigation comprised of two experiments. The first experimental material consisted of six
generations i.e. parents (P1 and P2), F1, F2 and back crosses (BC1 and BC2) of six crosses namely, Varuna x Bio-YSR;
Rohini x Bio-YSR; RH-8812 x Bio-YSR; Varuna x JMMWR-9348; Rohini x JMMWR-9348 and RH-8812 x
JMMWR-9348 to study the inheritance of white rust resistance and genetics of quantitative traits including seed yield
and its component characters as well as to investigate the association of white rust resistance with molecular markers.
The second experiment was carried out in Line x Tester mating design conducted to study the GCA and SCA effects
of parents and crosses, respectively along with heterosis of the resulted hybrids. Both the experiments were conducted
in the Department of Genetics and Plant Breeding, CCS Haryana Agricultural University (CCSHAU), Hisar, India
during two successive years of Rabi seasons 2012-13 and 2013-14. The results have shown that inheritance of white
rust resistance was governed by a single dominant gene which was also confirmed by SSR marker analysis. It has
been observed that there was a strong association between field results for inheritance of white rust and SSR marker
studied. Generation mean analysis revealed significant differences for all traits studied. The A, B, C and D individual
scales were also significant for most of the characters indicating thereby the presence of non-allelic interactions.
Additive component was significant for most of the characters and even as preponderant in magnitude over the
dominance component. Either all or any of the three types of epistatic interactions (i, j and l) were significant for most
of the cases and generally it was the “i" type of interaction which is more frequently prevailing for most of the traits
studied over the crosses. However, the magnitude and direction of estimates changed from cross to cross. Additive x
additive (i) type of interaction was reported for days to flowering, days to maturity, plant height (cm), number of
primary branches per plant, number of secondary branches per plant, siliqua length (cm), number of seeds per siliqua
and oil content (%). Duplicate type of interaction was apparent for days to flowering, days to maturity, plant height
(cm), number of primary branches per plant, number of secondary branches per plant, siliqua length (cm), number of
seeds per siliqua and oil content (%). Complementary type of interaction was also recorded for 1000 seed weight. The
GCA effects indicated that among females, RH-1120 was a good general combiner for number of primary branches
per plant, seed yield per plant (g) and 1000 seed weight (g); RH-1155 for number of primary branches per plant, main
shoot length (cm) and siliqua length (cm). Among the males, Bio-YSR was found to be a good general combiner for
plant height, number of secondary branches per plant and 1000 seed weight (g); JM-1 for days to flowering , seeds per
siliqua and seed yield per plant (g). On the basis of SCA effects, 5 crosses namely, RH-0845 x Bio-YSR; RH-1155 x
JM-1; RH-1139 x JMMWR-9348; RH-1152 x JM-1 and Kranti x JMMWR-9348 were found to be good for seed
yield per plant (g). Significant heterosis was observed for plant height (cm), main shoot length (cm), number of
siliquae on main shoot, siliqua length (cm), days to flowering, days to maturity and seed yield per plant (g). The
contribution of lines was in general more than testers toward total variance for every character except for days to
maturity and number of secondary branches per plant. SCA variances were higher than GCA variances which
indicated that one can go for hybrid breeding programme
Description
Keywords
Gene effects, Generation mean analysis, White rust, SSR markers, Indian mustard