Science Letters

Inheritance Pattern of Physio-Morphological Traits of Cotton under Drought Stress

Muhammad Waqas Amjid 1*, Tanwir Ahmad Malik 2, Muhammad Kausar Nawaz Shah 1, Muhammad Asif Saleem 3, Yasar Sajjad 4, Rashid Mehmood 1

1 Department of Plant Breeding and Genetics, PMAS Arid Agriculture University, Rawalpindi, Pakistan

2 Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad, Pakistan

3 Department of Plant Breeding and Genetics, Bahauddin Zakariya University, Multan, Pakistan

4 Department of Environmental Sciences, COMSATS Institute of Information Technology, Abbottabad, Pakistan

Abstract

Physiological traits play important role in breeding against drought stress. Intraspecific variability exists for drought tolerance in crop plants. Thirty seven upland cotton genotypes were screened in hydroponics on the basis of relative leaf water contents, excised leaf water loss and cell membrane stability. Drought stress was imposed by using 15% polyethylene-8000. On the basis of screening results, drought tolerant (FH-207) and drought susceptible (FH-901) genotypes were selected to develop F1, F2, BC1 and BC2 populations. The parents and all the populations were evaluated in the field under normal and drought stress conditions. The results of the genetic study revealed that all the traits were controlled by additive, dominance and epistatic type of gene actions. Correlation analysis revealed that relative leaf water content had a negative association with excised leaf water loss and positive association with cell membrane stability under drought stress conditions. Number of bolls/plant had positive correlation with relative leaf water contents and excised leaf water loss. These findings suggest that to develop a drought tolerant cultivar, selection of suitable plants should be delayed to the lateral generations so that genetic interactions could have been fixed. The positive association of number of bolls/plant with relative leaf water contents and cell membrane stability suggests that breeding for drought tolerance would improve yield in cotton under drought stress.

Keywords Upland cotton, hydroponic culture, relative leaf water contents, excised leaf water loss, cell membrane stability, drought.

Received December 01, 2015 Accepted January 31, 2016 Abstract Published February 15, 2016 Manuscript Published April 15, 2016

*Corresponding author Muhammad Waqas Amjid Email waqasamjid@hotmail.com Tel +92-300-0300021