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Wheat is the most popular and staple food for millions of people. It is severely affected by heat stress in many countries. Vegetative growth and reproductive phases in wheat differ in their sensitivity to temperature. Heat tolerant (GW-190) and Heat susceptible (J-2010-11) genotypes grown up to tillering and grain filling stages and Heat treatments (40°C and 45°C for 2h and 4h) were given using Heating House. After heat treatment samples were collected, the biochemical and physiological analysis such as Protein, Proline, Glycine betaine, Membrane stability, Relative water content, Germination percent, Seed vigour and Heat tolerant index were performed. Protein, proline and glycine betaine were found significantly highest 34.06 mg/g Fr. Wt., 13.70 mg% and 902.24 µg/F. wt respectively in heat tolerant genotype GW-190 at 45°C for 4 h at tillering stage. Membrane stability and relative water content were found significantly highest 56.83% and 86.15 % respectively in heat tolerant genotype GW-190 at tillering stage. Germination percent, Seed vigor and Heat tolerance index were found higher in control group of Heat tolerant GW-190 genotypes. Where, all the biochemical and physiological contents were found lower in heat susceptible J-2010-11 genotype. From the above results it was concluded that GW-190 was heat tolerant genotypes which is suitable for grown in area of high temperature and J-2010-11 was found heat susceptible.

Salt stress is an abiotic stress in cotton (G. hirsutum L.) that affects evenly yield. The present investigation carried out to study the significance of integrative biochemical and molecular approaches against salt stress in cotton. Four different verities, two salt tolerant (G.Cot.-16, GISV.218) and two susceptible (G. Cot.10, G.Cot.-100) were used screened at different salinity levels viz., 0.8 dS/m, 3 dS/m, 7 dS/m and 10 dS/m. Bio-chemical and molecular parameters analysed at seedling (15 DAS) and squaring stage (45 DAS). Biochemical traits like Protein content, total phenol content and Proline content was found to be increased with increasing salinity levels. Enzyme activity related to phenylpropanoid pathway (PAL, C4H and C3H) was found to be also increased with the advancement in salt stress, hence it implies possible role of these enzymes in imparting tolerance to salt stress in cotton. Reactive oxygen species (ROS) scavenging enzymes such as SOD, POD, CAT and PPO recorded increase in their activity at both seedling and squaring stages with increasing salinity levels. Expression analysis of key genes of phenylpropanoid pathway viz. PAL, C4H (C4H1 and C4H2) revealed maximum fold expression of PAL and C4H1 in the leaves, whereas least fold expression was observed for C4H2. Thus, it may be concluded that phenylpropanoid pathway play significant role in imparting tolerance against salt stress in cotton.

SUMMARY :The experiment was carried to screened cotton genotypes for salinity tolerance in the kharif season of 2016-17. Eleven cotton genotypes were selected and grown upto squaring stage in different soil ratio of normal soil and saline soil after that leaf samples were collected and all the biochemical parameters were recorded for screening of cotton genotypes for salinity tolerance. Genotypes GISV-218 and G. Cot-16 showed highest relative water content in all the treatment. Genotypes G.Cot-16, GISV-218 and BC-68-2 showed highest membrane stability in normal soil condition where genotypes G. Cot -16, GISV-218 and 76-1H-20 were showed highest membrane stability (78.79%, 78.29% and 74.70%, respectively) in saline soil. Range of proline content was (0.23 to 0.56 mg/g of tissue) in normal soil condition and it was (0.75 to 1.35 mg/g of tissue) in saline soil condition. Highest glycine

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