Neeraj KumarNeelam2018-11-052018-11-052018http://krishikosh.egranth.ac.in/handle/1/5810082840The present study was carried out with two chickpea (Cicer arietinum L.) genotypes viz. HC-3 and CSG-8962 having close phenology but differing in their sensitivity to salinity under screen house conditions. Forty days after sowing (DAS), the plants were given to single saline irrigation (Cldominated) having EC levels 2.0, 4.0 and 6.0 dS m-1. The control plants were irrigated with distilled water. Plant sampling was done at 85 and 105 days after sowing (DAS). The water potential (Ψw) of leaves, osmotic potential (Ψs) and RWC of leaves and roots decreased in both the genotypes under different saline irrigation levels i.e. 2.0, 4.0 and 6.0 dS m-1 as compared to control. Dry weight (g plant- 1) and plant height (cm) decreased with increase in saline irrigation levels, and it was observed more in CSG-8962 than HC-3. The proline, glycine betaine and total soluble carbohydrate (TSC) content of leaves and roots increased in both HC-3 and CSG-8962 genotype with increasing level of saline irrigation from control to 6.0 dS m-1 at both 85 and 105 DAS. More negative values of Ψw of leaves, Ψs of leaves and roots and better accumulation of osmotically active solutes, i.e. proline, glycine betaine and TSC in HC-3, helped in maintaining the higher RWC of these organs than noticed in CSG- 8962. Total chlorophyll content, chlorophyll stability index (CSI), anthocyanin contents and quantum yield (Fv / Fm) decreased in the two chickpea genotypes at both the sampling stages. A marked increase in hydrogen peroxide (H2O2), lipid peroxidation (MDA content) and relative stress injury (RSI %) was noticed in leaves and roots of HC-3 and CSG-8962 with increasing saline irrigation levels from control to 6.0 dS m-1. These parameter were much higher in CSG-8962 than HC-3 at both the sampling stages. The free radical scavenging activity also increased with increasing saline irrigation level from control to 6.0 dS m-1. Saline irrigation levels increased the Cl-, SO4 -2 and Na+/ K+ ratio from control to 6.0 dS m-1. The specific activities of ROS scavenging enzymes such as SOD, CAT, POX, GR, DHAR and MDHAR increased in leaves and roots of both the chickpea genotypes, upon increasing levels of saline irrigation from control to 6.0 dS m-1 at both the sampling stages The increase was more in HC-3 as compared to CSG-8962. Despite the increase in the activity of these enzymes, AsA content and glutathione (GSH) decreased at 6.0 dS m-1 salinity level as compared to their respective controls. Pollen viability (%), in vitro pollen germination and pollen tube length were also adversely affected by saline irrigation. The yield parameters like number of branches plant-1, number of pods plant-1, number of seeds plant-1, 100 seed weight and seed yield plant-1 decreased with increasing saline irrigation levels and decrease was more in CSG-8962 than HC-3. Based upon above physiological, biochemical, reproductive, yield and its attributing traits studied, it is found that chickpea genotype HC-3 performed relatively better under saline irrigation conditions and can further be used in crop improvement programmes of chickpea for salt tolerance.ennullThesis