Allelopathic Potential of Crop Residues for Weed Management in Wheat under Pakistan's Semi Arid Conditions
Allelopathic potential of crop residues for weed management in wheat under semi-arid conditions of Pakistan
Muhammad Ashraf
Professor of Agronomy, PMAS-Arid Agriculture University, Rawalpindi, Pakistan. drashraf_150@yahoo.com
RATIONALE
• Rainfed Wheat- Main winter crop grown by about 80% of the farmers on residual soil moisture, received during monsoon1. • Weeds infestation- a major yield reducing factor (25-30%↓); • If weeds are controlled, crop yield can be enhanced by about 37%2.
1 Khaliq et al., 2007) 2 (Bibi et al., 2005). Cont…..
Existing Weed Control systems: • Traditional weed control methods (Hand weeding) are time consuming, weather dependent and labor intensive1 ; + Socio-economic issues:[small land holdings, family size =8, poverty, migration to cities]
• Herbicides use is limited in drylands + these are expensive with Environmental hazards2; Reduced Nutritive value of many crops 3 and Herbicide resistance4.
1 (Naveed et al., 2008) 2 (Mancini et al., 2008) 3 (Nazarko et al., 2003). Cont…..
• WM programs should focus on environmental safety along with benefits to the farmers. • Alternate weed management systems need to be developed aimed to control weeds and raise the income of resource-poor farmers (increased crop yields) without despoiling the natural resource base.
ALTERNATE WEED MANAGEMENT OPTIONS
• Allelopathy − a mechanism of plant interference1 is a natural, inexpensive, environmentally safe and an organic approach to control weeds and increase crop yields while conserving the ecosystem2. • Sorghum is highly allelopathic3 • Sorghum residue may be effectively used to manage some of the important weeds in rainfed wheat without affecting crop in semi-arid environment4.
1 (Weston, 2005) 2 (Inderjit and Duke, 2003) 1 (Weston and Duke, 2003) 2 (Inderjit and Duke, 2003) Cont…..
• Water Extracts of different plant parts have different allelopathic potential 1. • Sunflower – possessed weed suppression ability 2 . •
Muhammad Ashraf
Professor of Agronomy, PMAS-Arid Agriculture University, Rawalpindi, Pakistan. drashraf_150@yahoo.com
RATIONALE
• Rainfed Wheat- Main winter crop grown by about 80% of the farmers on residual soil moisture, received during monsoon1. • Weeds infestation- a major yield reducing factor (25-30%↓); • If weeds are controlled, crop yield can be enhanced by about 37%2.
1 Khaliq et al., 2007) 2 (Bibi et al., 2005). Cont…..
Existing Weed Control systems: • Traditional weed control methods (Hand weeding) are time consuming, weather dependent and labor intensive1 ; + Socio-economic issues:[small land holdings, family size =8, poverty, migration to cities]
• Herbicides use is limited in drylands + these are expensive with Environmental hazards2; Reduced Nutritive value of many crops 3 and Herbicide resistance4.
1 (Naveed et al., 2008) 2 (Mancini et al., 2008) 3 (Nazarko et al., 2003). Cont…..
• WM programs should focus on environmental safety along with benefits to the farmers. • Alternate weed management systems need to be developed aimed to control weeds and raise the income of resource-poor farmers (increased crop yields) without despoiling the natural resource base.
ALTERNATE WEED MANAGEMENT OPTIONS
• Allelopathy − a mechanism of plant interference1 is a natural, inexpensive, environmentally safe and an organic approach to control weeds and increase crop yields while conserving the ecosystem2. • Sorghum is highly allelopathic3 • Sorghum residue may be effectively used to manage some of the important weeds in rainfed wheat without affecting crop in semi-arid environment4.
1 (Weston, 2005) 2 (Inderjit and Duke, 2003) 1 (Weston and Duke, 2003) 2 (Inderjit and Duke, 2003) Cont…..
• Water Extracts of different plant parts have different allelopathic potential 1. • Sunflower – possessed weed suppression ability 2 . •