Fertigation for precision farming in tomato (Solanum Iycopersicum L.)

Abstract

The investigation entitled “Fertigation for precision farming in tomato (Solanum lycopersicum L.)” was carried out at College of Agriculture, Vellayani during the period 2015-2016 to standardize a fertigation schedule for precision farming in tomato and to assess the impact of precision farming practices on growth and yield and also to work out the economics. The field experiment was conducted during the summer season of 2015 (February to June) in farmer’s field at Pirappancode, Thiruvananthapuram district. The experiment was laid out in split plot design with eight treatment combinations and two controls, with four replications. Four levels of nutrients (l1- 75 per cent RD of N and K, l2- 100 per cent RD of N and K, l3- 125 per cent RD of N and K, l4- 150 per cent RD of N and K) constituted the main plot treatments and two fertigation intervals (i1- fertigation once in four days, i2- fertigation once in eight days) constituted the sub plot treatments. The two control treatments were, control 1 (KAU ad hoc POP for precision farming) and Control 2 (KAU POP for conventional farming). The hybrid tomato Lakshmi grafted on wild brinjal was used for the study. Among different nutrient levels, l3 (125 per cent RD of N and K) recorded the highest DMP (219.42 g plant-1), number of fruits plant-1(33.67), fruit set percentage (62.77) , fruit yield (1.54 kg plant-1 and 42.36 t ha-1) and was significantly superior to other nutrient levels tested. Fertigation at four days interval (i1) recorded the highest LAI, DMP (224.21 g plant-1), number of fruits plant-1 (35.53), fruit set percentage (60.74) and fruit yield (1.61 kg plant-1 and 44.25 t ha-1) and was significantly superior to i2 (fertigation at eight days interval). Moisture studies indicated that both WUE and water productivity significantly varied with nutrient levels and fertigation intervals. The highest WUE (40.62 kg ha mm-1) and water productivity (5.26 kg ha mm-1) were observed at 125 per cent RD of N and K. Fertigation at four days interval (i1) registered significantly higher WUE and water productivity than i2. Application of 125 per cent RD of N and K (l3) recorded the highest root weight of 10.27 g and the highest root volume of 26.58 cm3 and was statistically on par with 150 and 100 per cent RD of N and K. The treatment i1 was significantly superior to i2 for all root characteristics. Uptake of N, P and K varied significantly with nutrient levels and fertigation intervals. The treatment l3 recorded the highest N, P and K uptake and it was statistically on par with l4. Fertigation at four days interval (i1) was significantly superior to i2, in nutrient uptake. Among different interactions, 125 per cent RD of N and K at 4 days interval (l3i1) registered the highest DMP (245.28 g plant-1) and was statistically on par with 150 per cent RD of N and K at four days interval (l4i1). Also, l3i1 recorded the highest fruit yield (1.92 kg plant-1 and 52.70 t ha-1) and number of pickings (7.33) and was significantly superior to other interactions studied. Economics of the study showed that l3i1 (125 per cent RD of N and K at four days interval) registered the highest net income of ₹ 6,61,515 ha-1 and B:C ratio of 2.69 and it was significantly superior to all other interactions. KAU ad hoc POP for precision farming (Control 1) was significantly superior to KAU POP for conventional farming (Control 2), for all growth attributes, yield attributes and yield. The treatment combination 125 per cent RD of N and K given as fertigation at four days interval (l3i1) was superior to control 1 and control 2 with respect to yield attributes, yield and economics. Based on the results of the present field investigation, it can be concluded that application of 125 per cent RD of N and K (93.75 kg N and 31.25 kg K ha-1) as urea and muriate of potash respectively, in 30 splits through fertigation at four days interval along with basal application of FYM @ 25 t ha-1 and P @ 40 kg ha-1 as rock phosphate is the best schedule for hybrid tomato under precision farming.