Cumulative effect of crop establishment method and herbicides on nutrient uptake, content and productivity of wheat in the Gird region of North India

A field experiment was conducted during Rabi 2019-20 and 2020-21 to evaluate the cumulative effects of crop establishment methods and herbicides on nutrient uptake and productivity of wheat in the Gird region of North India. Treatments comprised of three crop establishment methods viz., conventional tillage (CT), minimum tillage (MT) and zero tillage (ZT) in main plots along with seven weed control treatments as subplots. Significantly higher grain yield (4.81 t/ha) was recorded under ZT due to reduced weed density and biomass, compared to the other tillage practices. The highest grain and straw yields (5.16 and 7.50 t/ha) were obtained under two hand weeding with ZT, which was statistically at par with the application of clodinafop + metsulfuron (60+4 g/ha) under the ZT system. Significantly higher N, P and K uptake and content by wheat were recorded under CT, followed by MT and ZT. Among herbicide treatments, the lowest nutrient uptake was recorded in the weedy check, while the highest uptake was observed under two hand weeding at 30 and 60 days after sowing (DAS), which was statistically at par with clodinafop + metsulfuron-methyl (60+4 g/ha). However, weeds followed opposing trends. ZT had the highest harvest index (40.08 %) compared to MT and CT. Furthermore, among herbicide treatments the maximum harvest index was observed with two hand weeding at 30 and 60 DAS (40.85 %); which was statistically equal to clodinafop + metsulfuron-methyl (60+4) g/ha (40.30 %). Reduced tillage significantly decreased soil bulk density in ZT (1.33 g/cm³) compared to MT (1.35 g/cm³) and CT (1.36 g/cm³), according to soil analysis. On the other hand, porosity and organic carbon showed the opposite trends. Available nitrogen (N), phosphorus (P) and potassium (K) in soil were recorded significantly higher under CT, followed by MT and ZT. CT recorded lower values of soil available N and higher values of soil P and K, while ZT recorded higher values of soil available N and lower values of soil P and K during the two-year study. Significantly higher values of available soil N and K were recorded under CT, followed by MT and ZT. However, ZT recorded significantly lower values of available soil nitrogen and potash accompanied by higher values of soil phosphorus. On the other hand, ZT recorded significantly lower values of available soil N and K coupled with higher values of available soil K during the pooled analysis.