Kumar, Vandana A.Joshi, Prerna2021-09-202021-09-202021-02https://krishikosh.egranth.ac.in/handle/1/5810175944The multipurpose agroforestry tree species Grewia optiva, Bhimal (family Tiliaceae) distributed in mid-hills of north-western, western and central Himalayas (500-2500 m asl) is highly used for its green nutritious fodder during dry winter season. The three types of leaves L1 (soft, light green-coloured small-sized leaves), L2 (semi-hard, green-coloured medium-sized leaves) and L3 (hard,dark-green coloured medium-sized leaves) collected in six different growth stages (S1 through S6) varied from vegetative to reproductive phases. The S2L3 and S1L3 leaves showed the highest total soluble aqueous protein content (25.65±0.63 mg/g ) and total carbohydrate content (29.945 ± 6.12 mg/g ) respectively, whereas the total carbohydrate in flower (S3FL) and fruits (S4FR) were 4.45±0.14 mg/g and 16.99± 3.37 mg/g, respectively. The S4L3 had highest Mg content (69.1 mg/g), but Zn content (85.3μg/g) in it was lesser than that in S2L3 (89.4 μg/g). The Ca in S6L3 (39.22 mg/g), Cu in S5L3 (9.6μg/g) and Mn (222.2 μg/g) in S2L3 were the highest. The flower (S3FL) had better Mg (1.73 mg/g), Ca (14 mg/g), Cu (13.6 μg/g) and Mn (48.5 μg/g) than fruit (S4FR) which had higher Zn (17.1 μg/g) content than flower. Leaves of S6 showed highest TPC (166.46±2.46 mg GAE/gE) and FRAP (83.33±2.73 mg AAE/gE) and hydroxyl radical scavenging activity (IC50=393.92±0.99μg) whereas S4L3 showed highest TFC (20.329±0.576 mgQE/gE) and TAA (474.21±8.35 mg AAE/gE) suggesting that the antioxidant activity increased with decrease in temperature. The flower (S3FL) possessed greatest TPC (880.08±5.97 mg GAE/gE), TFC (137.45±2.37mg QE/gE), TAA (807.54±5.76 mg AAE/gE), FRAP (299.16±10.5mg AAE/gE) and hydroxyl radical scavenging activites (IC50= 309.022±1.12μg) than those of fruits and leaves. The TAA, FRAP and hydroxyl radical scavenging activity of flower was >2 times, > 4 times and >1.4 higher than average value of those of L3 leaves in 6 growth stages. The highest antioxidant enzyme activity of 0.105±0.004 U mg protein -1, 0.441 ± 0.005 U mg protein-1 and 6.507±0.05 U mg protein-1 were reported for CAT, SOD and POD in S6L3 indicating that the tree developed low temperature stress tolerance. Based on the nutritional and antioxidant qualities, G. optiva leaves, flowers and fruits were proposed to be used in late winter season as fodder when other sources of green fodder were unavailable which would benefit livestock.EnglishThesis