Irrigation scheduling inMentha arvensis L. based relay and sequential cropping with Triticum aestivum L.

Abstract

The soil of the experimental site was sandy loam in texture, neutral in reaction, rich in organic carbon, low in available nitrogen and high in available phosphorus and potassium. The bulk density of the top 0-15 cm soil was 1.46mg/m 3 . The basic infiltration rate was 1.3cm/hour. Twelve treatments comprising of three cropping systems (timely planted menthol mint, wheat + menthol mint relay system and wheat–late transplanted mint sequential cropping) and four irrigation schedules (IW:CPE ratio 0.6, 0.8, 1.0 and 1.2) were set in a Factorial Randomized Block Design with three replications. Different treatments failed to bring significant variations in number of tillers/m 2 at 65DAS. However, higher number of tillers/m 2 was scored by conventional wheat planting. The yield attributes of wheat (number of ears/m 2 , ear length, number of grains/ear, grain weight/ear and 1000 grain weight) expressed non-significant variations due to alteration in planting pattern. Timely planted sole mint exhibited the lowest mint oil equivalent yield, followed by the transplanted crop. The relayed crop yielded the maximum mint oil equivalent yield. Among different IW:CPE ratios, significant increase in mint oil equivalent yield was observed at higher moisture regimes. IW:CPE ratio 1.2 had the maximum and 0.6 the minimum mint oil equivalent yield. The interaction effect revealed that irrigation of relay cropped mint at IW:CPE ratio 1.2 produced the highest oil equivalent yield. The wheat + mint relay cropping system gave the maximum gross (Rs. 140079/ha) and net returns (Rs. 74509/ha) and B:C ratio (1.13). Timely sown sole mint fetched higher gross and net returns and B:C ratio than wheat–transplanted mint with non-significant differences. Irrigation at higher IW:CPE ratios resulted in significant increase in gross return for every successive irrigation levels. For net return and B:C ratio, IW:CPE ratio 1.2 proved to be the best although it was statistically at par with 1.0 IW:CPE ratio.