(go to
KOMUGI Home) (go
to WIS List) (go to NO.81
Contents)
Wheat Information Service
Number 81:18-19 (1995)
II. Research Information
Effect of heat stress on germinability of some wheat genotypes and
their hybrids
Rajiv K Sharma1 and J. P. Tandon2*
Division of Genetics, Indian Agricultural Research
Institute, New Delhi-110012, India
Wheat is primarily a cool season crop. Heat stress is known to affect
coleoptile length as well as number of primary roots and eventually
the germinability, in wheat. Rainfed wheat in India is required to be
grown little early to take advantage of the preceding monsoon rains.
This makes wheat germinate under relatively higher temperature
conditions. The study under report made use of eight wheat purelines
viz., Hindi 62, Narmada 4, Kalyansona, Kharchia 65, Sonalika, WH 283,
DWR 39 and HI 1011, and their all possible 28 hybrids excluding
reciprocals, to identify genotypes suitable for such heat stress
conditions. A random sample of 12 well formed seeds was taken for
each genotype for each of the three replications studied. Four seeds
wrapped in water soaked germinating paper were kept in one
petriplate. This was repeated for all the genotypes over the two
temperatures of 20 and 36C. After seven days, observations on
coleoptile length, average number of radicals and total radical
length were recorded.
Analysis of variance indicated significant differences among entries
for all the characters (Table 1).
Temperature x entries interaction was found to be non-significant
only for average number of radicals. Therefore, only pooled results
are presented for this character. Mean, range and coefficients of
variation for different characters over the two temperature regimes
as also the genotypes least effected by heat stress are presented in
Table 1. It can be seen from the table that
genotypes viz. DWR 39, WH 283 and Kharchia 65 resisted the stress
effect. Many hybrids involving Hindi 62 as one of the parents showed
minimum change due to heat stress. These genotypes hold promise to
serve as good starting material for any breeding work aiming at
developing wheat genotypes tolerant to heat during germination and
early post germination phase.
Present address: 1: Division of Vegetable Crops, Indian Agricultural
Research Institute. New Delhi110012, India, 2: Indian Council of
Agricultural Research. Krishi Bhawan. New Delhi 110001. India
(go to
KOMUGI Home) (go
to WIS List) (go to NO.81
Contents)