STUDIES ON TRIPLE TEST CROSS ANALYSIS IN CUCUMBER (Cucumis sativus L.)
Loading...
Date
2019-01
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
UHF, NAUNI
Abstract
ABSTRACT
The present investigation entitled “Studies on triple test cross analysis in cucumber (Cucumis sativus L.)” was
carried out at the Experimental Research Farm of Department of Vegetable Science, Dr YS Parmar University of
Horticulture and Forestry, Nauni-Solan, Himachal Pradesh during rainy season of 2016 and 2017. During the study, two
experiments were carried out. The first experiment was comprised of 45 triple test cross progenies derived by mating 15
lines randomly selected as individual plant progenies from F2 generation of LC-1-1 × K-75. These lines were further mated
with three testers namely LC-1-1 (L1), K-75 (L2) and their single cross F1 (L3) to estimate the genetic variation from a
cross between two parental lines. The data were subjected to the biometrical analysis by following Triple Test Cross
Method of Kearsey and Jinks (1968) to detect epistasis and estimates of additive and dominance components of genetic
variance. The second experiment was constituted of 30 hybrid combinations resulted from the crossing of ten lines with three
testers of cucumber to identify appropriate cross combinations and to approximate the inbred line performance in F1
combination, using GCA and SCA variances and their effects along with heterosis. The data were subjected to Line × Tester
analysis as proposed by Kempthorne (1957). For both the experiments, the observations were recorded on days to first
female flower opening, node number bearing first female flower, days to marketable maturity (days), number of marketable
fruits per plant, harvest duration (days), fruit length (cm), fruit breadth (cm), average fruit weight (g), yield per plant (kg),
total soluble solid (0B), incidence of fruit fly (%), severity of powdery and downy mildew (%) except seed traits in
experiment-I. The observations on different seed traits (seed germination, seed vigour index I and II) were recorded only in
case of experiment-II. Good quantum of genetic variability has been generated through triple test cross progenies with
respect to different traits studied as revealed by the significant analysis of variance. For triple test cross (TTC) analysis the
parent viz., P12, P13, P11, P8, P5 (Lines) and L3 followed by L1(Testers), whereas, ttc progenies/cross combinations viz.,P12×
L3, P13 × L3, P11 × L3, P11× L1 and P8 × L3manifested high mean values and heterotic effects for marketable fruit yield and
found superior for majority of trait under study. Heterotic effects were observed in almost all the characters studied and
supported through genetic analysis of the triple test cross (TTC) progenies, where the preponderance of epistasis, additive
and dominance components of genetic variation was observed for earliness, marketable yield, quality and insect pest and
disease traits. The kind of genetic variance revealed from triple test cross can be exploited by intermating selected
individuals in early segregating generations with delayed selection in later generations, diallel selective mating/biparental
mating or recurrent selection followed by pedigree method to exploit both additive and non-additive components along with
epistasis. The Line × Tester studies concluded that parents UHF-CUC-11, UHF-CUC-13, UHF-CUC-6, UHF-CUC-15,
UHF-CUC-8 and Solan Srijan were found superior for majority of traits under study on the basis of their mean performance
and general combining ability studies. Cross-combinations UHF-CUC-11 × Solan Srijan, UHF-CUC-13 × Solan Srijan,
UHF-CUC-6 × K-75, UHF-CUC-15 × Solan Srijan, UHF-CUC-8 × Solan Srijan and UHF-CUC-7 × Poinsette on the basis
of mean performance, specific combining ability and heterosis studies excelled well for all the traits studied. Hence, these
parents and cross combination can be tested further at multi-locations before releasing as a substitute of already exiting
varieties/hybrids of cucumber and getting transgressive segregants in the later generations
Description
Keywords
null