Effect of Heat Stress on Tissue Culture Response in Wheat Genotypes
Loading...
Date
2019
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
DRPCAU, Pusa
Abstract
The effect of heat stress on tissue culture responses like callogenesis and
organogenesis including green structures formation and rhizogenesis was studied in
four wheat genotypes Sonara-64, PBW-343, HD-2967 and SIDS. Media were
identified for callus formation and organogenesis from cultured mature embryos, the
best medium for callus formation was MS + 4mg/l 2,4-D and for organogenesis MS +
1mg/l BAP + 0.5gm/l NAA. Mature embryos from pre-heat treated seeds were
induced to develop callus and on the basis of calculated heat susceptibility index
(HSI) and heat tolerance index (HTI), the genotype HD-2967 was the most heat
tolerant followed by PBW-343. Genotype SIDS was the most heat sensitive followed
by Sonara-64. The formed calli under controlled and heat stress were further pre-heat
treated and cultured on differentiating medium for organogenesis. Genotype HD-2967
showed the best response followed by PBW-343, Sonara-64 and SIDS respectively
under heat stress indicating their relative heat tolerance. Thus based on tissue culture
responses under heat stress genotype HD-2967 and PBW-343 were heat tolerant and
Sonara-64 and SIDS were heat sensitive.
Molecular characterization study of eleven genotypes resulted in successful
amplification with 12 SSR primer pairs. A total of 79 allelic variants were detected
with an average of 6.07 alleles per locus and total 46 unique alleles were observed
with an average of 3.53 unique alleles per locusat 13 SSR loci. The highest number
Name of Student : Anant Raj
Admission No./Registration No. : M/AB/199/2017-18
MajorAdvisor : Dr. Harsh Kumar
Degree to be awarded : M.Sc.(Ag) in Agricultural Biotechnology
Major Subject : Agricultural Biotechnology
Minor Subject : Plant Breeding & Genetics
Year : 2019
Total pages of the Thesis : 70+i-xiv (Bibliography)
Title of the research problem : “Effect of heat stress on tissue culture
response in wheat genotypes”
of alleles per locus was observed in the B genome (38 alleles) as compared to A (24)
and D (17) genomes. Polymorphism information content (PIC) value ranged from
0.327 for the primer pairXgwm160 to 0.878 for the primer pairXgwm 577with an
average of 0.764. The similarity coefficient was the maximum between HD-2967 and
BWL-9022 (0.519) and the minimum (0.0) infour pair-wise combinations HD-2967
with Purulla, PBW-343 with Sonalika, BWL-9022 with Sonalika and KSG-1186 with
Sonalika. It ranged from 0.0 to 0.519 indicating the presence of wide range of genetic
diversity at molecular level among the genotypes. Dendrogram was constructed using
Dice similarity coefficients. The entries were divided into three groups on the basis of
drawing phenon line at 0.20 coefficient of similarity level.Cluster A grouped together
highly heat tolerant genotypes (PBW-343, HD-2967, BWL-9022 ), cluster B grouped
moderately heat tolerant genotypes (Purulla, Seri-82, SALEMBO, KSG-1186 ) except
CIANO-T-79 ( moderately heat susceptible) and cluster C grouped together highly
heat susceptible genotypes (Sonara-64, SIDS, Sonalika) of wheat. Thus, molecular
characterization revealed that genotypes under study were having genetically different
levels of heat tolerance.