Fertigation studies in banana (Musa acuminata AAA) cv. red banana

Abstract

The present study entitled ‘Fertigation studies in banana (Musa acuminata AAA) cv. Red banana was carried out at the Department of Fruit Science, College of Agriculture, Vellayani, Thiruvanathapuram, during the period 2020-2023. Red banana or Chenkadali (fruit locally known as kappa pazham) is one of the most relished and highly priced varieties of Kerala rich in antioxidants, beta carotene, vitamin C and vitamin B6. For increased yield and productivity, standardization of nutrient requirement and fertigation schedule is pertinent to ensure steady supply of nutrients and water at the right growth phases. Considering these aspects, the present study was proposed to standardize the nutrient levels and fertigation schedule for yield improvement in red banana under fertigation system. The experiment was conducted in combinations of four different fertigation levels (F) and three levels of split applications of fertilizers (S), laid out in randomized block design replicated thrice with 12 plants per plot at a spacing of 2.1 x 2.1 m. Fertigation treatments were fixed based on the soil test-based N and K recommendation. The fertigation levels were F1 – 60 % recommended dose (RD) of N and K, F2 – 80 % RD of N and K, F3– 100 % RD of N and K, F4 – 120 % RD of N and K and the split application levels include S1– equal splits of N and K at weekly intervals upto 12 months, S2 – equal splits of N and K at fortnightly intervals upto 12 months, S3 – split application of N and K according to the phenological growth stage from 5th to 12th week (30% N and 10% K), 13th to 25th week (35% N and 10% K), 26th to 37th week (20% N and 30% K), 38th to 49th week (15% N and 25% K), 50th to 52nd week (25% K), control KAU POP (200: 200: 400 g NPK plant-1 year-1), soil application of nutrients with conventional land management and drip irrigation). Organic manure (10 kg FYM plant 1) and P (200 g plant-1) was given uniformly to all treatments as basal. The biometric parameters recorded showed that nutrient level at 120% RDF of N and K (F4) recorded the highest values for plant height, pseudo stem girth, leaf number, total functional leaf area and leaf area index. Lesser number of days to shooting, shoot to harvest, crop duration and phyllocron was recorded for 80% RDF of N and K (F2). Fertigation schedule according to the growth stage of the crop (S3) 156 recorded higher plant height, pseudo stem girth, leaf number, total functional leaf area and leaf area index, it also recorded earliness in days to shooting, shoot to harvest and crop duration. F2S3 interaction recorded earliness in days to shooting, shoot to harvest and crop duration which was on par with F3S3 for days to shooting. The yield parameters including bunch weight and fingers per bunch was observed to be the highest with application of 80 % RDF of N and K (F2) which was on par with F3 and F4. Finger length, finger girth and finger weight were the highest for F3 which was on par with F4, yield (t/ha) was the highest for F2 which was on par with F3 and F4. Length of bunch, bunch weight, fingers per bunch, fingers per hand, finger length, girth and weight were observed to be higher with application of fertilizers according to the growth stage of the crop (S3). F2S3 recorded the highest length of bunch, hands per bunch, fingers per bunch and fingers per hand. F3S3 recorded the highest yield and B: C ratio and was on par with F2S3, F4S1, F4S3, F3S1. The quality parameters of fruit including TSS, total sugar, reducing sugar, non reducing sugar and carotenoid content were the highest in F3 which was on par with F2. Total sugar, non-and reducing sugar recorded highest values for S3 which was on par with S1. F2S3 recorded the highest total sugar and reducing sugar which was on par with F3S3. The nutrient analysis of fruit at harvest stage recorded the highest N content on fruits for F4 and N and P content for S3. The interaction of fertilizer level and split application recorded the highest N and K content for F4S3 and F3S1 respectively. The highest NPK content on index leaf was recorded in nutrient levels F3 and F4 and in split application, S3. The interaction effect recorded higher N content for F3S3 and K content for F3S1. The soil analysis after the experiment recorded higher EC and organic carbon content for F4 and F3 respectively. The split application of fertilizers according to growth stages of the crop (S3) recorded higher organic carbon content. Interaction effect of nutrient level and fertigation schedule recorded higher electrical conductivity for F4S3 and organic carbon content for F3S1. The N and K content of soil recorded higher values for F3 and F4 respectively. Interaction effect of nutrient level and split application 157 of fertilizers record higher N and K content for F4S3. Among the micronutrients, Fe content was found to be maximum in F1 at fertilizer level and F2S1 interaction. Application of 80% RD of N and K in split doses according to the growth stage of the crop exhibited superior performances across biometric, yield and quality parameters in red banana under fertigation system with high B: C ratio. The treatment could save 20 % of fertilizers, reduced the crop duration by 100 days, increased the yield by 10.8% when compared to the control.