K Banyal, SanjeevSharma, Ishani2023-01-252023-01-252021-11-17https://krishikosh.egranth.ac.in/handle/1/5810192785The present investigation entitled “Studies on the effect of micronutrients and plant growth regulators on growth and cropping of Kinnow mandarin under HDP” were conducted in the experimental farm of Department of Fruit Science, COHF, Neri were conducted during the year 2020-2021. The studies were carried out on 4-year-old Kinnow plants, planted at a spacing of 2×2m. In the 1st experiment the effect of foliar micronutrient and PGRs application on growth, cropping and fruit quality of Kinnow mandarin. The experiment was laid down in Randomized Block Design with 11 treatments and 4 replications. Micronutrients and PGR’s were applied as foliar spray twice i.e. in last week of February and 3rd week of August. Results revealed highest increase in plant height (66.75 cm), trunk girth (3.15 cm)and leaf area (36.42 cm2), maximum fruit set (68.35%), final fruit retention (26.35%), fruit breadth (7.95 cm) fruit weight (192.4 g), fruit volume (256.7 cm2), fruit yield per plant (27.23kg), TSS (12.17 ˚brix) and minimum Fruit drop (75.45 %), number of seeds per fruit(18.25) and rind thickness (2.90 mm) with the foliar application of 2,4-D @ 20ppm +ZnSO4 @ 0.4%+FeSO4 @ 0.4%) + Boric Acid @ 0.25%. Minimum titratable acidity content (0.67 %), maximum fruit length (6.36 cm), TSS: acid (17.86) and total sugar (10.65 %) was recorded with treatment T9 (GA3 @ 20 ppm + ZnSO4 @ 0.4 % + FeSO4 @ 0.4 % + Boric Acid @ 0.25%) and ascorbic acid (39.29 mg/100g) was found in with NAA @ 20 ppm + ZnSO4 @ 0.4 % + FeSO4 @ 0.4 % + Boric Acid @ 0.25 %. In second experiment, Fruits were harvested on different dates viz., D1 (17th January), D2 (24th January), D3 (31st January), D4 (7th February) D5 (14th February). The best fruit size, TSS, acidity, TSS: acid and fruit weight was found in fruits harvested on 31st January 2021.EnglishThesis