The extract of crofton weed(Eupatorium adenophorum) inhibits seed germination and weed growth;however,the physiological mechanisms underlying the effect of crofton weed extract on the modulation of seedling growth and...The extract of crofton weed(Eupatorium adenophorum) inhibits seed germination and weed growth;however,the physiological mechanisms underlying the effect of crofton weed extract on the modulation of seedling growth and root system development remain largely unclear.In this study,we investigated the effects of the leaf extract of crofton weed(LECW) on primary root(PR) growth in maize seedlings.Treatment with LECW markedly inhibited seed germination and seedling growth in a dose-dependent manner.Physiological analysis indicated that the LECW induced reactive oxygen species(ROS) accumulation in root tips,thereby leading to cell swelling and deformation both in the root cap and elongation zone of root tips,finally leading to cell death in root border cells(RBCs) and PR growth inhibition.The LECW also inhibited pectin methyl esterase(PME) activity,thereby decreasing the RBC number.Taken together,our results indicated that the LECW inhibited PR growth by inducing ROS accumulation and subsequent cell death in RBCs.The present study provides a better understanding of how the LECW modifies root system development and provides insight for evaluating the toxicity of crofton weed extracts in plants.展开更多
Crofton weed is an invasive weed in southwestern China. The activities of several antioxidative enzymes involved in plant protection against oxidative stress were assayed to determine physiological aspects of the crof...Crofton weed is an invasive weed in southwestern China. The activities of several antioxidative enzymes involved in plant protection against oxidative stress were assayed to determine physiological aspects of the crofton weed that might render the plant vulnerable to environmental stress. Stresses imposed on crofton weed were heat (progressively increasing temperatures: 25 ℃, 30 ℃, 35 ℃, 38℃ and 42 ℃ at 24 h intervals), cold (progressively decreasing temperatures: 25 ℃, 20 ℃, 15℃, 10 ℃ and 5℃ at 24h intervals), and drought (without watering up to 4days). The three stresses induced oxidative damage as evidenced by an increase in lipid peroxidation. The effect varied with the stress imposed and the length of exposure. The activity of superoxide dismutase (SOD) increased in response to all stresses but was not significantly different from the controls (P 〈 0.05) when exposed to cold stress. Catalase (CAT) activity decreased in response to heat and drought stress but increased when exposed to cold conditions. Guaiacol peroxidase (POD) and glutathione reductase (GR) activities increased in response to cold and drought but decreased in response to heat stress. The activity of ascorbata peroxidase (APX) responded differently to all three stresses. Monodehydroascorbate reductase (MDHAR) activity decreased in response to heat and drought, and slightly increased in response to the cold stress but was not significantly different from the controls (P 〈 0.05). The activity of dehydroascorbata reductase (DHAR) increased in response to all three stresses. Taken together, the co-ordinate increase of the oxygen-detoxifying enzymes might be more effective to protect crofton weed from the accumulation of oxygen radicals at low temperatures rather than at high temperatures.展开更多
Eupatorium adenophorum Spreng. was introduced in Yunnan Province of China around 1940. Since then it has been spreading rapidly, particularly in the southern and southwestern parts of China and caused serious economic...Eupatorium adenophorum Spreng. was introduced in Yunnan Province of China around 1940. Since then it has been spreading rapidly, particularly in the southern and southwestern parts of China and caused serious economic loss. The biological research and inte-grated control on E. adenophorum were carried out from 1980's in Yunnan Province. Together with other 15 invasive external species, the weed has been listed in the White Paper by The State Environmental Protection Administration of China. This paper briefly reviews the studies on natural distribution, biological character, ecological character, chemical component, hazard, potential application and the control of E. adenophorum. The research direction for this invasive external species in future was also discussed.展开更多
基金the Key Project of Science and Technology of Shanxi Province(20150311016-5)the Science and Technology innovation Foundation of Shanxi Agricultural University(2017ZZ09)。
文摘The extract of crofton weed(Eupatorium adenophorum) inhibits seed germination and weed growth;however,the physiological mechanisms underlying the effect of crofton weed extract on the modulation of seedling growth and root system development remain largely unclear.In this study,we investigated the effects of the leaf extract of crofton weed(LECW) on primary root(PR) growth in maize seedlings.Treatment with LECW markedly inhibited seed germination and seedling growth in a dose-dependent manner.Physiological analysis indicated that the LECW induced reactive oxygen species(ROS) accumulation in root tips,thereby leading to cell swelling and deformation both in the root cap and elongation zone of root tips,finally leading to cell death in root border cells(RBCs) and PR growth inhibition.The LECW also inhibited pectin methyl esterase(PME) activity,thereby decreasing the RBC number.Taken together,our results indicated that the LECW inhibited PR growth by inducing ROS accumulation and subsequent cell death in RBCs.The present study provides a better understanding of how the LECW modifies root system development and provides insight for evaluating the toxicity of crofton weed extracts in plants.
基金Supported by Knowledge Innovation Project of Chinese Academy of Sciences(No.KSCX1-SW-13-03)National Natural Science Foundation of China(No.30470337)K C Wong Fellowship,Royal Society of UK.
文摘Crofton weed is an invasive weed in southwestern China. The activities of several antioxidative enzymes involved in plant protection against oxidative stress were assayed to determine physiological aspects of the crofton weed that might render the plant vulnerable to environmental stress. Stresses imposed on crofton weed were heat (progressively increasing temperatures: 25 ℃, 30 ℃, 35 ℃, 38℃ and 42 ℃ at 24 h intervals), cold (progressively decreasing temperatures: 25 ℃, 20 ℃, 15℃, 10 ℃ and 5℃ at 24h intervals), and drought (without watering up to 4days). The three stresses induced oxidative damage as evidenced by an increase in lipid peroxidation. The effect varied with the stress imposed and the length of exposure. The activity of superoxide dismutase (SOD) increased in response to all stresses but was not significantly different from the controls (P 〈 0.05) when exposed to cold stress. Catalase (CAT) activity decreased in response to heat and drought stress but increased when exposed to cold conditions. Guaiacol peroxidase (POD) and glutathione reductase (GR) activities increased in response to cold and drought but decreased in response to heat stress. The activity of ascorbata peroxidase (APX) responded differently to all three stresses. Monodehydroascorbate reductase (MDHAR) activity decreased in response to heat and drought, and slightly increased in response to the cold stress but was not significantly different from the controls (P 〈 0.05). The activity of dehydroascorbata reductase (DHAR) increased in response to all three stresses. Taken together, the co-ordinate increase of the oxygen-detoxifying enzymes might be more effective to protect crofton weed from the accumulation of oxygen radicals at low temperatures rather than at high temperatures.
基金This study was supported by Project of Chinese Academy of Science Knowledge Innovation Program (KSCX1-SW-13-0X-0X) and National Natural Science Foundation of China (30470337)
文摘Eupatorium adenophorum Spreng. was introduced in Yunnan Province of China around 1940. Since then it has been spreading rapidly, particularly in the southern and southwestern parts of China and caused serious economic loss. The biological research and inte-grated control on E. adenophorum were carried out from 1980's in Yunnan Province. Together with other 15 invasive external species, the weed has been listed in the White Paper by The State Environmental Protection Administration of China. This paper briefly reviews the studies on natural distribution, biological character, ecological character, chemical component, hazard, potential application and the control of E. adenophorum. The research direction for this invasive external species in future was also discussed.