Performance of papaya variety ‘Surya’ under fertigation and foliar nutrition

Abstract

Effects of fertigation and foliar nutrition with micronutrients on papaya flowering, yield and fruit quality parameters were studied during the period 2018 – 2020 at Instructional Farm, College of Agriculture, Vellayani, Thiruvananthapuram, Kerala, India. A field experiment consists of 14 treatments replicated thrice was laid out based on randomized block design. A combination of four fertigation doses of 75 %, 100 %, 125 % and 150 % Recommended Dose of Fertilizers (RDF) of N (304.89, 406.52, 508.15 and 609.78 gm urea plant-1 year-1 respectively based on soil test data in 76 fertigation) and K (426.25, 568.33, 710.42 and 852.50 gm muriate of potash plant?¹ year?¹ respectively based on soil test data in 76 fertigation) and three foliar sprays (1.0 % 19:19:19 at bimonthly interval starting from 4 MAP (Month After Planting) to 16 MAP, 0.5% ZnSO4 + 0.3% borax at 4th, 8th, 12th and 16th MAP and water spray at bimonthly interval starting from 4 MAP to 16 MAP) where compared with soil application of recommended dose of NPK (187:170:341 g NPK plant-1 year-1 based on soil test data) (control 1) and 187:170:341 g NPK plant-1 year-1 based on soil test data as organic manures as combination of FYM (Farm Yard Manure), poultry manure and vermicompost in the ratio of 2:1:1 (control 2). Application of 100 % recommended dose of N and K through fertigation at weekly interval from one MAP to 20 MAP and foliar sprays of 0.5 % ZnSO4 and 0.3 % borax at 4th, 8th, 12th and 16th MAP (T5) initiated earliness in flowering (142.67 days) and harvest (275.00 days). However, plants receiving 100 % recommended dose of N and K through fertigation at weekly interval from one MAP to 20 MAP with foliar sprays of 1% 19:19:19 at bimonthly interval starting from 4 MAP to 16 MAP (T4) significantly improved the fruit weight, number of fruits per plant and total yield per plant in papaya variety ‘Surya’ and it was on par with T5. Fruit quality parameters namely TSS (Total Soluble Solids), ascorbic acid and total sugars were found significantly highest in T5 and lowest titratable acidity was also recorded in T5. Hence, treatment T5 which is found superior in initiating early harvest, with higher yield and good quality characters in papaya variety ‘Surya’ can be recommended to farmers.