Creation of new genetic diversity in cotton germplasm through chemically induced mutation

Abstract

Being an important cash crop of Pakistan, cotton has a major share in the agriculture based economy. Due to continuous breeding of same germplasm to produce new high yielding cultivars, genetic base of the germplasm has become narrowed down and yield of cotton is stagnant since last two decades. Keeping in view these facts, major objective of the study was to enhance the genetic variation of the available germplasm of cotton by treating with chemical mutagens. To achieve this, an experiment was conducted using three treatments of mutagen (sodium azide) and a control. Data were collected for morphological traits, yield traits and fiber quality traits. Results showed highly significant differences among genotypes and treatments. Application of sodium azide at 5 mM concentration of sodium azide does not affect any traits and the performances of all traits were reduced with treatment of 15 and 25 mM concentration of sodium azide. Fiber traits, number of nodes per plant and number bolls per plant does not respond to the treatments of sodium azide. Genetic diversity was further analyzed with SSR markers. It is concluded from the results that sodium azide may be a useful mutagen (at 15 and 25 mM concentration) to create genetic variation in cotton germplasm to be used for a breeding program.