Amaranthus retroflexus L. is a serious and widespread malignant weed in soybean fields in Heilongjiang Province. Exploring the dormancy characteristics of A. retroflexus L. seeds and the physiological response of its ...Amaranthus retroflexus L. is a serious and widespread malignant weed in soybean fields in Heilongjiang Province. Exploring the dormancy characteristics of A. retroflexus L. seeds and the physiological response of its seedlings to acifluorfen sodium can provide a basis for further researches on its resistance mechanism. Using newly harvested and stored A. retroflexus L. seeds for one year as experimental materials, the effects of different concentrations of HCl, NaOH, water temperature, gibberellic acid(GA) and polyethylene glycol(PEG) on the dormancy and germination of A. retroflexus L. seeds were studied. The sensitivity of A. retroflexus L.to acifluorfen sodium was determined using bioassay. The effects on leaf chlorophyll content and target enzyme activity were studied at a normal dosage of 360 g a.i. hm^(-2) and a doubling dosage of 720 g a.i. hm^(-2) of acifluorfen sodium. Newly harvested seeds exhibiting dormancy were soaked in water of various temperatures and in different concentrations of NaOH and HCl, which were ineffective in breaking the seed dormancy. GA could break seed dormancy, and the highest seed germination rate reached 93.33% when they were soaked at 3 000 mg·L^(-1) for 72 h and 4 000 mg·L^(-1) for 48 h. The drought stress was simulated with a 15%-25% polyethylene glycol solution, which had no significant effect on the seed germination rate. The GR_(50) value of acifluorfen sodium for A. retroflexus L. was 705.7 g a.i. hm^(-2), which was 1.96 times the recommended dose in the field. After the application of different doses of acifluorfen sodium, the chlorophyll content of A. retroflexus L. reached its minimum value 3 days after treatment(DAT), and then gradually increased. The activity of the target enzyme protoporphyrinogen oxidase(PPO) reached the highest value at 7 DAT under different dosages, and gradually returned to normal levels thereafter. Soaking with gibberellin was an effective method to break seed dormancy. A. retroflexus L. seeds had certain drought resistance during the germination process. A. retroflexus L. was not sensitive to acifluorfen sodium and acifluorfen sodium ether, and could not effectively inhibit the PPO activity, indicating that A. retroflexus L. had target resistance to acifluorfen sodium.展开更多
New herbicide options are needed for postemergence (POST) broadleaf weed control in adzuki bean. A field study, of five experiments, was conducted over a three-year period (2014, 2015, 2016) in Ontario to evaluate the...New herbicide options are needed for postemergence (POST) broadleaf weed control in adzuki bean. A field study, of five experiments, was conducted over a three-year period (2014, 2015, 2016) in Ontario to evaluate the tolerance of adzuki bean to the POST application of acifluorfen (600 and 1200 g·ai·ha-1), fomesafen (240 and 480 g·ai·ha-1), bentazon (1080 and 2160 g·ai·ha-1), imazethapyr (100 and 200 g·ai·ha-1) and halosulfuron-methyl (75 and 150 g·ai·ha-1). Acifluorfen and fomesafen applied POST caused as much as 12% visible injury at the 1X rate and 20% visible injury at the 2X rate but had no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield. Bentazon caused as much as 23% visible injury at 1080 g·ai·ha-1 and 28% visible injury at 2160 g·ai·ha-1 but caused no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield at either rate, except at 2160 g·ai·ha-1 which reduced shoot dry weight 20% and height 12%. Imazethapyr caused as much as 22% visible injury at 100 g·ai·ha-1 and 34% visible injury at 200 g·ai·ha-1 but caused no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield at either rate except at 200 g·ai·ha-1 which delayed maturity slightly. Halosulfuron-methyl caused as much as 65% visible injury and reduced shoot dry weight, height and yield 64%, 41%, and 28%, respectively. This research concludes that acfluorfen, fomesafen, bentazon, imazethapyr and halosulfuron at the rates evaluated can cause the significant injury in adzuki bean.展开更多
The objective of this research was to evaluate the efficacy of various pre-emergence (PRE) and post-emergence (POST) herbicides for the control of volunteer adzuki bean (Vigna angularis (Willd.) Ohwi & Ohashi) in ...The objective of this research was to evaluate the efficacy of various pre-emergence (PRE) and post-emergence (POST) herbicides for the control of volunteer adzuki bean (Vigna angularis (Willd.) Ohwi & Ohashi) in soybean (Glycine max L.). Trials were conducted at two locations in 2005, 2006, 2007, and 2009. Experiments were arranged in a randomized complete block design with either five PRE or nine POST herbicides. Volunteer adzuki bean interference in soybean resulted in yield loss of up to 25%. Cloransulam-methyl, linuron, metribuzin, flumetsulam, and imazethapyr applied PRE provided up to 6, 24, 14, 8, and 0% control, respectively at 8 weeks after emergence (WAE), while acifluorfen, fomesafen, bentazon, thifensulfuron-methyl, cloransulam-methyl, imazethapyr, and imazethapyr plus bentazon applied POST provided 2, 2, 5, 34, 6, 4, and 12% control, respectively at 8 weeks after application (WAA). Generally, with the aforementioned herbicides, soybean yield was equivalent to the weedy control and soybean grain contamination with adzuki bean seed was consistently above the 1% maximum threshold. Chlorimuron-ethyl and glyphosate applied POST provided up to 84 and 94% visual control at 8 WAA, respectively, decreased adzuki bean density, biomass, and seed production, and generally decreased soybean contamination with adzuki bean below the 1% threshold. The only herbicides evaluated in this study that controlled volunteer adzuki bean in soybean were chlorimuron-ethyl (9 g ai.ha-1) and glyphosate (900 g ai.ha-1) applied POST. All the other PRE and POST herbicides evaluated did not provide adequate control of volunteer adzuki bean in soybean.展开更多
为明确高效氟吡甲禾灵、三氟羧草醚的联合作用类型及和25%高氟吡·三氟羧草醚乳油对花生田杂草的防除效果以及对花生的安全性,采用茎叶喷雾法测定了2种除草剂室内联合作用类型,并对筛选的25%高氟吡·三氟羧草醚乳油进行了田间...为明确高效氟吡甲禾灵、三氟羧草醚的联合作用类型及和25%高氟吡·三氟羧草醚乳油对花生田杂草的防除效果以及对花生的安全性,采用茎叶喷雾法测定了2种除草剂室内联合作用类型,并对筛选的25%高氟吡·三氟羧草醚乳油进行了田间防效验证。结果表明,高效氟吡甲禾灵、三氟羧草醚以1∶4复配对防除花生田一年生禾本科杂草有增效作用,25%高氟吡·三氟羧草醚乳油的推荐使用剂量为150.0~187.5 g a.i./hm^(2),药后46 d对杂草的总鲜质量防效可达到92.82%~95.72%。高效氟吡甲禾灵、三氟羧草醚复配对防除狗尾草等杂草增效作用明显,25%高氟吡·三氟羧草醚乳油能够有效防除花生田一年生杂草,并对花生安全。展开更多
基金Supported by the National Major Special Project for the Cultivation of New Genetically Modified Biological Varieties(Topic ZX08011-003)。
文摘Amaranthus retroflexus L. is a serious and widespread malignant weed in soybean fields in Heilongjiang Province. Exploring the dormancy characteristics of A. retroflexus L. seeds and the physiological response of its seedlings to acifluorfen sodium can provide a basis for further researches on its resistance mechanism. Using newly harvested and stored A. retroflexus L. seeds for one year as experimental materials, the effects of different concentrations of HCl, NaOH, water temperature, gibberellic acid(GA) and polyethylene glycol(PEG) on the dormancy and germination of A. retroflexus L. seeds were studied. The sensitivity of A. retroflexus L.to acifluorfen sodium was determined using bioassay. The effects on leaf chlorophyll content and target enzyme activity were studied at a normal dosage of 360 g a.i. hm^(-2) and a doubling dosage of 720 g a.i. hm^(-2) of acifluorfen sodium. Newly harvested seeds exhibiting dormancy were soaked in water of various temperatures and in different concentrations of NaOH and HCl, which were ineffective in breaking the seed dormancy. GA could break seed dormancy, and the highest seed germination rate reached 93.33% when they were soaked at 3 000 mg·L^(-1) for 72 h and 4 000 mg·L^(-1) for 48 h. The drought stress was simulated with a 15%-25% polyethylene glycol solution, which had no significant effect on the seed germination rate. The GR_(50) value of acifluorfen sodium for A. retroflexus L. was 705.7 g a.i. hm^(-2), which was 1.96 times the recommended dose in the field. After the application of different doses of acifluorfen sodium, the chlorophyll content of A. retroflexus L. reached its minimum value 3 days after treatment(DAT), and then gradually increased. The activity of the target enzyme protoporphyrinogen oxidase(PPO) reached the highest value at 7 DAT under different dosages, and gradually returned to normal levels thereafter. Soaking with gibberellin was an effective method to break seed dormancy. A. retroflexus L. seeds had certain drought resistance during the germination process. A. retroflexus L. was not sensitive to acifluorfen sodium and acifluorfen sodium ether, and could not effectively inhibit the PPO activity, indicating that A. retroflexus L. had target resistance to acifluorfen sodium.
文摘New herbicide options are needed for postemergence (POST) broadleaf weed control in adzuki bean. A field study, of five experiments, was conducted over a three-year period (2014, 2015, 2016) in Ontario to evaluate the tolerance of adzuki bean to the POST application of acifluorfen (600 and 1200 g·ai·ha-1), fomesafen (240 and 480 g·ai·ha-1), bentazon (1080 and 2160 g·ai·ha-1), imazethapyr (100 and 200 g·ai·ha-1) and halosulfuron-methyl (75 and 150 g·ai·ha-1). Acifluorfen and fomesafen applied POST caused as much as 12% visible injury at the 1X rate and 20% visible injury at the 2X rate but had no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield. Bentazon caused as much as 23% visible injury at 1080 g·ai·ha-1 and 28% visible injury at 2160 g·ai·ha-1 but caused no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield at either rate, except at 2160 g·ai·ha-1 which reduced shoot dry weight 20% and height 12%. Imazethapyr caused as much as 22% visible injury at 100 g·ai·ha-1 and 34% visible injury at 200 g·ai·ha-1 but caused no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield at either rate except at 200 g·ai·ha-1 which delayed maturity slightly. Halosulfuron-methyl caused as much as 65% visible injury and reduced shoot dry weight, height and yield 64%, 41%, and 28%, respectively. This research concludes that acfluorfen, fomesafen, bentazon, imazethapyr and halosulfuron at the rates evaluated can cause the significant injury in adzuki bean.
文摘The objective of this research was to evaluate the efficacy of various pre-emergence (PRE) and post-emergence (POST) herbicides for the control of volunteer adzuki bean (Vigna angularis (Willd.) Ohwi & Ohashi) in soybean (Glycine max L.). Trials were conducted at two locations in 2005, 2006, 2007, and 2009. Experiments were arranged in a randomized complete block design with either five PRE or nine POST herbicides. Volunteer adzuki bean interference in soybean resulted in yield loss of up to 25%. Cloransulam-methyl, linuron, metribuzin, flumetsulam, and imazethapyr applied PRE provided up to 6, 24, 14, 8, and 0% control, respectively at 8 weeks after emergence (WAE), while acifluorfen, fomesafen, bentazon, thifensulfuron-methyl, cloransulam-methyl, imazethapyr, and imazethapyr plus bentazon applied POST provided 2, 2, 5, 34, 6, 4, and 12% control, respectively at 8 weeks after application (WAA). Generally, with the aforementioned herbicides, soybean yield was equivalent to the weedy control and soybean grain contamination with adzuki bean seed was consistently above the 1% maximum threshold. Chlorimuron-ethyl and glyphosate applied POST provided up to 84 and 94% visual control at 8 WAA, respectively, decreased adzuki bean density, biomass, and seed production, and generally decreased soybean contamination with adzuki bean below the 1% threshold. The only herbicides evaluated in this study that controlled volunteer adzuki bean in soybean were chlorimuron-ethyl (9 g ai.ha-1) and glyphosate (900 g ai.ha-1) applied POST. All the other PRE and POST herbicides evaluated did not provide adequate control of volunteer adzuki bean in soybean.
文摘为明确高效氟吡甲禾灵、三氟羧草醚的联合作用类型及和25%高氟吡·三氟羧草醚乳油对花生田杂草的防除效果以及对花生的安全性,采用茎叶喷雾法测定了2种除草剂室内联合作用类型,并对筛选的25%高氟吡·三氟羧草醚乳油进行了田间防效验证。结果表明,高效氟吡甲禾灵、三氟羧草醚以1∶4复配对防除花生田一年生禾本科杂草有增效作用,25%高氟吡·三氟羧草醚乳油的推荐使用剂量为150.0~187.5 g a.i./hm^(2),药后46 d对杂草的总鲜质量防效可达到92.82%~95.72%。高效氟吡甲禾灵、三氟羧草醚复配对防除狗尾草等杂草增效作用明显,25%高氟吡·三氟羧草醚乳油能够有效防除花生田一年生杂草,并对花生安全。
