HEAT TOLERANCE IN PEARL MILLET : A REVIEW
A. K. Yadav, R. K. Arya, M. K. Singh, Dharmender Kumar and Ravish Panchta
Institute of Himalayan Bioresource Technology (CSIR),
Palampur-176 061 (H. P.), India
*(e-mail : email@example.com)
(Received : 14 May 2016; Accepted : 22 June 2016)
Global warming may cause serious problem in agricultural production, particularly in arid and semi-arid regions of the world. As the heat stress affects the seed germination, plant growth and development, resulting in drastic reduction in yield. Pearl millet is a multipurpose crop grown in these areas due to its tolerance to high temperature/drought. But, further improvement for thermo tolerance is of instant need, for economization of agriculture in these areas. Therefore, to develop/identify heat tolerant genotypes, knowledge of screening methods, heat tolerance mechanisms along with breeding techniques are important. Heat stress decreases the rate of germination and may also inhibit the germination depending on heat tolerance of the genotype. A lot of genetic variability is available for heat tolerance in pearl millet. The different screening techniques, viz. STI, SSTI, MTS, etc. may be utilized for screening the germplasm for heat tolerance. Breeding for heat tolerance information of genetic variability, gene action (additive and non-additive), heritability, stability and correlation in relation to heat tolerance is available. Gene interaction on heat tolerance showed its complex nature of inherence. To overcome the heat stress various mechanisms such as maintenance of membrane stability, scavenging of reactive oxygen species (ROS), production of anti-oxidants, osmo-regulation of solutes and synthesis of heat stroke proteins (HSPs) were used. Both conventional as well as molecular breeding techniques were utilized for genetic improvement for heat tolerance.
Key words: Heat tolerance, screening techniques, genetic improvement, pearl millet