Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are ...Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are infesting the crops such as Cynodon dactylon, Conyza canadensis, Tribulus terrestris, and Cyperus rotundus, etc. Recent studies indicate that conventional tillage （CT） is more productive than zero tillage （ZT）/reduced tillage （RT）. Performance of cotton under three tillage systems, viz., ZT, RT and CT; and five herbicides, i.e., haloxyfop-R-methyl 10.8 EC （108 g a.i. ha^-1）, lactofen 24 EC （168 g a.i. ha^-1）, haloxyfop 10.8 EC ＋ lactofen 24 EC, hand weeding, and weedy check were evaluated during 2010-2011 at Gomal University, D.I.Khan, Pakistan, to explore the best management option for effective weed control, enhanced yield and quality of cotton grown after wheat. The results revealed that hand weeding and Haloxyfop as post emergence alone or in combination with Lactofen reduced weed density to the minimum irrespective of the tillage systems. Excessive rainfall and cooler temperature limited cotton growth and yield in 2010. The adverse weather conditions had more adverse effect on boll weight under ZT and RT than CT. Haloxyfop ＋ lactofen produced higher seed cotton yield in RT than ZT, however, it could not exceed CT. Broad-spectrum herbicides x CT produced the highest number of bolls/plant, boll weight and seed cotton yield. Fiber quality and net returns were also the highest in broad-spectrum herbicides x CT. In conclusion, broad-spectrum herbicides under CT were more productive in wheat based cropping system on silty clay soil of D.I.Khan.展开更多
A study was conducted in a split-plot design to evaluate the effect of fertilizer placement method on weed growth and grain yield in a dry-seeded rice (DSR) system. Main-plot treatments were four fertilizer placement ...A study was conducted in a split-plot design to evaluate the effect of fertilizer placement method on weed growth and grain yield in a dry-seeded rice (DSR) system. Main-plot treatments were four fertilizer placement methods: between narrow rows (between 15-cm-wide rows of the pattern 25-15-25 cm), between uniform rows (between 20-cm-wide rows), within uniform rows, and surface broadcast. Subplot treatments were three weed control methods: herbicide-treated, nontreated, and weed-free. Weed biomass was greater in the nontreated plots than in the herbicide-treated plots. Herbicide application reduced weed biomass by 89% to 99% compared with the nontreated control. Fertilizer placement did not influence weed biomass in the herbicide-treated plots;however, it greatly influenced biomass in the nontreated plots. Fertilizer placement on the surface increased weed biomass (69 -71 g·m–2) compared with the placement of fertilizer below the soil surface (37 -57 g·m–2). Fertilizer placement did not influence weed density and biomass at 60 days after planting. Nontreated plots yielded 700 to 2080 kg·ha–1. Grain yield was similar between the herbicide-treated (2660-3250 kg·ha–1) and weed-free (2620-3430 kg·ha–1) plots. Grain yield was not influenced when basal fertilizer was banded within (2390-2500 kg·ha–1) or between rows (2530-2650 kg·ha–1). However, grain yield decreased when basal fertilizer was broadcast on the soil surface (2200 kg·ha–1). The results of our study demonstrated that rice yield was usually lower with surface broadcast of fertilizer than with subsurface fertilizer treatments. In conclusion, surface broadcast of basal fertilizer may result in high weed pressure in DSR systems.展开更多
There <span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> a limited number of soil-applied herbicides available for broad-spectrum</span><spa...There <span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> a limited number of soil-applied herbicides available for broad-spectrum</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> weed control in dry bean production in Ontario, Canada. Four experiments were conducted from 2017 to 2019 in southwestern Ontario to compare the efficacy of six soil-applied grass herbicides [trifluralin (600 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), ethalfluralin (810 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), pendimethalin (1080 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), S-metolachlor (1050 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), dimethenamid-p (544 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) and EPTC (3400 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">)] and halosulfuron (35 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) applied alone and in combination, applied preplant incorporated (PPI), on white bean tolerance and yield, and weed control efficacy. There was no white bean injury from the herbicide treatments eva</span><span style="font-family:Verdana;">luated. Grass herbicides (trifluralin, ethalfluralin, pendimethalin, S-metolachlor</span><span style="font-family:Verdana;"> dimethenamid-P and EPTC) controlled velvetleaf 0% - 82%, pigweeds 87% - 99%, common ragweed 0% - 93%, common lambsquarters 81% - 99%, wild mustard 0% - 71%, barnyardgrass 98% - 100% and green foxtail 98% - 99%. Halosulfuron controlled velvetleaf 98%, pigweeds 94%, common ragweed 90% - 94%, common lambsquarters 97%, wild mustard 98% - 100%, barnyardgrass 19% - 24% and green foxtail 20% - 25%. Tankmixes of halosulfuron with soil-applied grass herbicides provided ≥93% control of the weed species evaluated. Reduction in density and biomass generally followed the same trend as visible control with herbicide treatments evaluated. Weed interference reduced white bean seed yield 70%. Seed yield was 53% - 66% of </span><span style="font-family:Verdana;">the weed-free control with trifluralin, ethalfluralin, pendimethalin, S-metolachlor</span><span style="font-family:Verdana;"> and dimethenamid-P, 81% of the weed-free control with EPTC, 58% of the weed-free control with halosulfuron, and 87% - 95% of the weed-free control with halosulfuron tankmixes with the grass herbicides evaluated. Based on these results, halosulfuron in combination with trifluralin, ethalfluralin, pendimethalin, S-metolachlor, dimethenamid-p and EPTC, applied PPI at rates evaluated, can be used to effectively control common annual grass and broadleaf weeds in white beans.</span></span>展开更多
A field experiment was conducted from 2002-2005 on a sandy clay loam red and lateritic soil under irrigation in a farmer＇s field at Senkapur （Lat. 23°36.79′ N, Long. 87°38.14′E, Elev. 46 m AMSL）, Birbhu...A field experiment was conducted from 2002-2005 on a sandy clay loam red and lateritic soil under irrigation in a farmer＇s field at Senkapur （Lat. 23°36.79′ N, Long. 87°38.14′E, Elev. 46 m AMSL）, Birbhum, West Bengal, India. The objective was to provide the temporal changes of weed diversity and density, ecology, and impact of rotational cropping systems on different crops under double and triple cropping systems with improved （IP） and farmer＇s packages （FP）. There was significantly higher weed density in FP than in IP on all years. Grasses and sedges were more in vegetable-based rotational systems; but grasses and broad leaf weeds （BLWs） were more in rice-based rotational systems. The lowest weed population was in vegetable-based systems. Grasses increased in rice-based systems but gradually decreased in vegetable-based systems in subsequent years. Sedge density was higher in vegetable- than in rice-based rotational systems. Density of BLWs was higher but that of sedges was lower in rice-based rotational systems as compared to vegetable-based systems. Density of BLWs gradually decreased in all rotational systems over the years in both packages. Density of weeds decreased gradually in subsequent years indicating the positive effect of rotational systems on suppression of weeds. Results indicate that the weed density can be reduced through judicious diversified rotational cropping systems. Peanut-brinjal＋brinjal, okra-chilli＋chilli and cucumber-cabbage-basella systems greatly reduced the weed density in both packages, and hence can be recommended for the lateritic belt of lower Gangetic plain of eastern India.展开更多
文摘Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are infesting the crops such as Cynodon dactylon, Conyza canadensis, Tribulus terrestris, and Cyperus rotundus, etc. Recent studies indicate that conventional tillage （CT） is more productive than zero tillage （ZT）/reduced tillage （RT）. Performance of cotton under three tillage systems, viz., ZT, RT and CT; and five herbicides, i.e., haloxyfop-R-methyl 10.8 EC （108 g a.i. ha^-1）, lactofen 24 EC （168 g a.i. ha^-1）, haloxyfop 10.8 EC ＋ lactofen 24 EC, hand weeding, and weedy check were evaluated during 2010-2011 at Gomal University, D.I.Khan, Pakistan, to explore the best management option for effective weed control, enhanced yield and quality of cotton grown after wheat. The results revealed that hand weeding and Haloxyfop as post emergence alone or in combination with Lactofen reduced weed density to the minimum irrespective of the tillage systems. Excessive rainfall and cooler temperature limited cotton growth and yield in 2010. The adverse weather conditions had more adverse effect on boll weight under ZT and RT than CT. Haloxyfop ＋ lactofen produced higher seed cotton yield in RT than ZT, however, it could not exceed CT. Broad-spectrum herbicides x CT produced the highest number of bolls/plant, boll weight and seed cotton yield. Fiber quality and net returns were also the highest in broad-spectrum herbicides x CT. In conclusion, broad-spectrum herbicides under CT were more productive in wheat based cropping system on silty clay soil of D.I.Khan.
文摘A study was conducted in a split-plot design to evaluate the effect of fertilizer placement method on weed growth and grain yield in a dry-seeded rice (DSR) system. Main-plot treatments were four fertilizer placement methods: between narrow rows (between 15-cm-wide rows of the pattern 25-15-25 cm), between uniform rows (between 20-cm-wide rows), within uniform rows, and surface broadcast. Subplot treatments were three weed control methods: herbicide-treated, nontreated, and weed-free. Weed biomass was greater in the nontreated plots than in the herbicide-treated plots. Herbicide application reduced weed biomass by 89% to 99% compared with the nontreated control. Fertilizer placement did not influence weed biomass in the herbicide-treated plots;however, it greatly influenced biomass in the nontreated plots. Fertilizer placement on the surface increased weed biomass (69 -71 g·m–2) compared with the placement of fertilizer below the soil surface (37 -57 g·m–2). Fertilizer placement did not influence weed density and biomass at 60 days after planting. Nontreated plots yielded 700 to 2080 kg·ha–1. Grain yield was similar between the herbicide-treated (2660-3250 kg·ha–1) and weed-free (2620-3430 kg·ha–1) plots. Grain yield was not influenced when basal fertilizer was banded within (2390-2500 kg·ha–1) or between rows (2530-2650 kg·ha–1). However, grain yield decreased when basal fertilizer was broadcast on the soil surface (2200 kg·ha–1). The results of our study demonstrated that rice yield was usually lower with surface broadcast of fertilizer than with subsurface fertilizer treatments. In conclusion, surface broadcast of basal fertilizer may result in high weed pressure in DSR systems.
文摘There <span style="font-family:Verdana;">are</span><span style="font-family:Verdana;"> a limited number of soil-applied herbicides available for broad-spectrum</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> weed control in dry bean production in Ontario, Canada. Four experiments were conducted from 2017 to 2019 in southwestern Ontario to compare the efficacy of six soil-applied grass herbicides [trifluralin (600 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), ethalfluralin (810 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), pendimethalin (1080 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), S-metolachlor (1050 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">), dimethenamid-p (544 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) and EPTC (3400 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">)] and halosulfuron (35 g ai ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">) applied alone and in combination, applied preplant incorporated (PPI), on white bean tolerance and yield, and weed control efficacy. There was no white bean injury from the herbicide treatments eva</span><span style="font-family:Verdana;">luated. Grass herbicides (trifluralin, ethalfluralin, pendimethalin, S-metolachlor</span><span style="font-family:Verdana;"> dimethenamid-P and EPTC) controlled velvetleaf 0% - 82%, pigweeds 87% - 99%, common ragweed 0% - 93%, common lambsquarters 81% - 99%, wild mustard 0% - 71%, barnyardgrass 98% - 100% and green foxtail 98% - 99%. Halosulfuron controlled velvetleaf 98%, pigweeds 94%, common ragweed 90% - 94%, common lambsquarters 97%, wild mustard 98% - 100%, barnyardgrass 19% - 24% and green foxtail 20% - 25%. Tankmixes of halosulfuron with soil-applied grass herbicides provided ≥93% control of the weed species evaluated. Reduction in density and biomass generally followed the same trend as visible control with herbicide treatments evaluated. Weed interference reduced white bean seed yield 70%. Seed yield was 53% - 66% of </span><span style="font-family:Verdana;">the weed-free control with trifluralin, ethalfluralin, pendimethalin, S-metolachlor</span><span style="font-family:Verdana;"> and dimethenamid-P, 81% of the weed-free control with EPTC, 58% of the weed-free control with halosulfuron, and 87% - 95% of the weed-free control with halosulfuron tankmixes with the grass herbicides evaluated. Based on these results, halosulfuron in combination with trifluralin, ethalfluralin, pendimethalin, S-metolachlor, dimethenamid-p and EPTC, applied PPI at rates evaluated, can be used to effectively control common annual grass and broadleaf weeds in white beans.</span></span>
文摘A field experiment was conducted from 2002-2005 on a sandy clay loam red and lateritic soil under irrigation in a farmer＇s field at Senkapur （Lat. 23°36.79′ N, Long. 87°38.14′E, Elev. 46 m AMSL）, Birbhum, West Bengal, India. The objective was to provide the temporal changes of weed diversity and density, ecology, and impact of rotational cropping systems on different crops under double and triple cropping systems with improved （IP） and farmer＇s packages （FP）. There was significantly higher weed density in FP than in IP on all years. Grasses and sedges were more in vegetable-based rotational systems; but grasses and broad leaf weeds （BLWs） were more in rice-based rotational systems. The lowest weed population was in vegetable-based systems. Grasses increased in rice-based systems but gradually decreased in vegetable-based systems in subsequent years. Sedge density was higher in vegetable- than in rice-based rotational systems. Density of BLWs was higher but that of sedges was lower in rice-based rotational systems as compared to vegetable-based systems. Density of BLWs gradually decreased in all rotational systems over the years in both packages. Density of weeds decreased gradually in subsequent years indicating the positive effect of rotational systems on suppression of weeds. Results indicate that the weed density can be reduced through judicious diversified rotational cropping systems. Peanut-brinjal＋brinjal, okra-chilli＋chilli and cucumber-cabbage-basella systems greatly reduced the weed density in both packages, and hence can be recommended for the lateritic belt of lower Gangetic plain of eastern India.
