Weed control in strip planted wheat under conservation agriculture practice is more effective than conventional tillage

Smallholder farms in South Asia are rapidly adopting herbicides for labour saving weed control in crops but effective weed management technologies have not been well developed. Weed management technologies are especially in demand for the emerging Conservation Agriculture practices involving minimum soil disturbance planting and retention of crop residues. The present study was undertaken to determine the effectiveness of crop reesidue retention relative to herbicides and hand weeding for weed control and yield of strip-planted, irrigated wheat on the Eastern Gangetic Plain of Bangladesh. Wheat (cv. BARI Wheat ۲۶) was grown during the winter season (November-March) in ۲۰۱۴-۱۵ (first year) and ۲۰۱۵-۱۶ (second year) after monsoon rice, with strip planting (SP) and conventional tillage (CT) combined with the six weed control practices [T۱: CT + three hand weedings (HW) (Control), T۲: pre-plant herbicide (PRE) + SP + one HW, T۳: PRE + SP + pre-emergence herbicide (PE), T۴: PRE + SP + post-emergence herbicide (PO), T۵: PRE + SP + PE + PO, T۶: PRE + SP + weed-free (WF)], and two levels of retained rice straw viz., M۰: no-mulch and M۵۰: ۵۰% standing mulch. The PRE herbicide (glyphosate), PE herbicide (pendimethalin) and PO herbicide (carfentrazone-ethyl) were applied at recommended dose and time. The combination of applied PRE, SP, followed by sequential application of PE and PO herbicides and the retention of ۵۰% mulch achieved the highest weed control efficacy. Furthermore, this practice produced the ۲۴% higher yield and ۴۰% higher economic returns relative to the control treatment. Hence, the study concluded that the SP integrated with effective herbicides and residue mulching-based weed control options was more profitable than manual weeding in CT while also saving labour for wheat production.Smallholder farms in South Asia are rapidly adopting herbicides for labour saving weed control in crops but effective weed management technologies have not been well developed. Weed management technologies are especially in demand for the emerging Conservation Agriculture practices involving minimum soil disturbance planting and retention of crop residues. The present study was undertaken to determine the effectiveness of crop reesidue retention relative to herbicides and hand weeding for weed control and yield of strip-planted, irrigated wheat on the Eastern Gangetic Plain of Bangladesh. Wheat (cv. BARI Wheat ۲۶) was grown during the winter season (November-March) in ۲۰۱۴-۱۵ (first year) and ۲۰۱۵-۱۶ (second year) after monsoon rice, with strip planting (SP) and conventional tillage (CT) combined with the six weed control practices [T۱: CT + three hand weedings (HW) (Control), T۲: pre-plant herbicide (PRE) + SP + one HW, T۳: PRE + SP + pre-emergence herbicide (PE), T۴: PRE + SP + post-emergence herbicide (PO), T۵: PRE + SP + PE + PO, T۶: PRE + SP + weed-free (WF)], and two levels of retained rice straw viz., M۰: no-mulch and M۵۰: ۵۰% standing mulch. The PRE herbicide (glyphosate), PE herbicide (pendimethalin) and PO herbicide (carfentrazone-ethyl) were applied at recommended dose and time. The combination of applied PRE, SP, followed by sequential application of PE and PO herbicides and the retention of ۵۰% mulch achieved the highest weed control efficacy. Furthermore, this practice produced the ۲۴% higher yield and ۴۰% higher economic returns relative to the control treatment. Hence, the study concluded that the SP integrated with effective herbicides and residue mulching-based weed control options was more profitable than manual weeding in CT while also saving labour for wheat production.

کلیدواژه ها:

Herbicides ، Mulchs ، Strip planting ، Weed control ، Yield