Effect of Fertigation with Sources and Levels of Fertilizer on Yield, Quality and Use Efficiency of Water and Fertilizer in Green Chilli (Capsicum annuum L., Chillies)

Field experiments were conducted on red sandy loam soils of agronomy field unit, Main Research Station, University of Agricultural Sciences, Bengaluru during 2006 and 2007 to study the effect of fertigation with different sources and levels of fertilizer on quality, yield and use efficiency of water and fertilizers in green chillies. The experiment comprised of 12 treatments viz; four sources of fertilizers (urea, single superphosphate (SSP), muriate of potash (MOP); monoammonium phosphate(MAP), potassium nitrate (KNO₃); Soil application of urea, single superphosphate, muriate of potash) and three levels of NPK (75, 100 and 125% Recommended NPK) in randomized complete block design with three replications. The recommended fertilizer dose for green chillies was 150:33:62.5 kg NPK/ha. Drip irrigation was given daily at 0.8 E Pan to all except treatments 10 to12 which received surface irrigation at 0.8E.Pan once in a week. Fertigation was done through Dosatron by feeding the required solution prepared as per the dose and source of fertilizer. All the fertigation treatments received 11 feedings at weekly interval. Observations on soil moisture, soil and leaf water potential, yield and quality were made. Water and fertilizer use efficiency and benefit cost ratio were worked out. The results revealed higher total soluble solids (4.13, 4.32 and 3.98° Brix respectably at 3^rd, 6^th and 9^th harvest and significantly higher ascorbic acid content 142.31 mg/100g) in MAP, KNO₃ fertigation at 125% recommended NPK and lower values were recorded with soil application of Urea, SSP and MOP at 75% Rec NPK. Similar trend was noticed with respect to fruit yield. (19.97/ha) and water use efficiency (WUE) (31:0 kg/ha mm). While fertilizer use efficiency (FUE) was higher with MAP, KNO₃ fertigation at 75% recommended NPK (71.6 kg/kg NPK). The least WUE of 16.3 kg/ha mm was observed with soil application of urea, SSP, MOP at 75% recommended NPK. Similarly soil application of traditional fertilizers at 125% recommended NPK caused the lowest FUE of 35.3 kg/kg NPK.