Relative cell injury based screening of Gossypium hirsutum L. for heat tolerance

Working group session: 
Germplasm and Genetic Stocks
Presentation type: 
oral
Authors: 
Salman, Muhammad; Tehseen Azhar, Muhammad; Ali, Zulfiqar; Ali Khan, Asif; Karim, Ihsan
Presenter: 
Salman, Muhammad
Correspondent: 
Salman, Muhammad
Abstract: 
Due to global warming, temperature of the world is increasing day by day and it appeared as one of the major abiotic stress in the world specifically for agricultural production. According to estimates about 65-70 % yield losses have been observed in cotton due to heat stress in Pakistan. Heat also reduces the expression of Cry gene in Bt cottons and heat stress also cause square and flower shedding as well as pollen sterility in cotton. An experiment was conducted in the fields of University of Agriculture, Faisalabad to screen eighty cotton accessions for heat tolerance. To calculate RCI%, two samples of leaf disc were collected from each genotype grown in cotton field; one from one side of the mid rib of the leaf and second from the other side of the mid rib of the same leaf. One sample was used as control at room temperature in distilled water filled (10cc) falcon tubes while the second sample was also kept in similar falcon tubes at 50oC in water bath. Then both the samples were kept in incubator for 24 hours at 22oC then EC1 and EC2 were measured for each sample separately, before and after autoclave treatment. By using EC1 and EC2 values, RCI% of eighty genotypes were calculated. The genotypes VH-142 and VH-259 were found to be heat tolerant with RCI% values of 48 and 54.9 respectively while VH-282 and DNH-40 genotypes were found to be heat susceptible with RCI% values of 93.2 and 94.5 respectively in these studies. The identified heat tolerant in present investigation can be used for the development of heat tolerant and high yielding cotton genotypes.