Effect of paddy straw mulch, irrigation regimes and nitrogen levels on the performance of spring transplanted bell pepper in semi-arid environment of South-Western Punjab

Abstract

A 4-years study was conducted to investigate the effect ofthree irrigation levels (I1= IW/CPE=0.6, I2=0.9, I3=1.2) andthree nitrogen levels (N1=100 kg/ha, N2=125 kg/ha, N3=150kg/ha) on growth, yield, quality and water use efficiency(WUE) of spring transplanted bell pepper with paddy strawmulching (PSM) @ 6 t/ha (M1) vis-à-vis without mulching(M0). Significantly higher fruit yield was recorded withhigher number of irrigations (I3) as compared to I1 and I2levels. The fruit yield under M0I3 was statistically at parwith that under M1I2 implying saving of 5-7 irrigations byusing PSM. Low nitrogen fertilization with PSM (N1M1)yielded at par with higher nitrogen fertilization withoutmulching (N3M0) revealing that 50 kg N/ha may be saved byusing PSM. The dry matter, ascorbic acid and chlorophyll(a, b and total chlorophyll) in fruits harvested from M1 plotswere higher than those from M0 plots whereas, the capsaicincontent in fruit was 14.6% lower in M1 plots than those frombare soil. The dry matter, vitamin C and chlorophyll (a, b andtotal) in fruits were the lowest in I1 and the highest valueswere recorded in I3 whereas the capsaicin content exhibitedthe contrary trend. A significant increase in fruit dry matter,ascorbic acid and chlorophyll (a, b and total); and a decreasein capsaicin content was observed with increase in nitrogendose from 100 kg/ha to 150 kg/ha. Water use (WU) wasslightly higher under M0 as compared to M1 plots, whereas,the WUE and profile water use (PWU) were higher in M1than in M0 plots. The WU and PWU exhibited an increasingtrend with increasing frequency of irrigation whereas theWUE showed a decreasing trend. The WU and WUE valueswere the highest at N3 and the lowest at N1 level. The organiccarbon, available nitrogen, phosphorus and potassiumcontent of surface soil (0-15 cm) increased with PSM thanthose in bare soil.