[Objective] This study aimed to explore the effects of spores and crude toxins of Helminthosporium gramineum Rabenh f. sp. echinochloae（HGE） on the ac- tivity of defensive enzymes of barnyardgrass [Echinochloa crus-...[Objective] This study aimed to explore the effects of spores and crude toxins of Helminthosporium gramineum Rabenh f. sp. echinochloae（HGE） on the ac- tivity of defensive enzymes of barnyardgrass [Echinochloa crus-galli （L.） Beauv.]. [Method] The effects of spores and crude toxins of HGE, as well as the mixture of spores and crude toxins on the activity of defensive enzymes in barnyardgrass were determined under laboratory conditions. [Result] Spores and crude toxins of HGE had varying degrees of effects on PAL and POD activity, and no obvious effect on SOD activity in barnyardgrass. In addition, spores and toxins had some similar im- pacts on the defensive enzymes in barnyardgrass. [Conclusion] Since toxins have similar effects on the hosts as spores of fungal pathogen do, they can be a substi- tute for the fungal pathogen in studying the partial pathogenic mechanism of this pathogen due to its complexity in pathogenic process.展开更多
Rice false smut is caused by ascomycete Villosiclava virens, whose potential alternative hosts have been assumed previ- ously. Here its potential alternative hosts were surveyed and identified from 2008 to 2013 in the...Rice false smut is caused by ascomycete Villosiclava virens, whose potential alternative hosts have been assumed previ- ously. Here its potential alternative hosts were surveyed and identified from 2008 to 2013 in the main rice-growing regions in China. Two common weeds in paddy fields, Digitaria sanguinalis Scop. and Echinochloa crusgalli （L.） Beauv., were found to present the similar symptoms to smut diseases in a few individuals in 2012 and 2013 in Zhejiang and Sichuan provinces of China, respectively. After the examinations of the spore morphology, their infection and extension mode in hosts, pathogen cell wall components, and molecular identification, the two pathogens were identified to be the Basidiomycetes, Ustilago syntherismae and Ustilago trichophora, respectively. So far there has been no alternative host of V. virens to be identified in China. These suggest that the alternative hosts of V. virens, if they do exist, are not possible to play an important role in the pathogen life cycle and the disease epidemics.展开更多
为有效控制福建地区直播稻田禾本科杂草的危害，以莆田市仙游县游洋乡的水稻种植基地为试验点，选择测定1％噁嗪草酮悬浮剂、10％双草醚悬浮剂和20％氰氟草酯油悬浮剂等3种除草剂对稗草、千金子等禾本科杂草的防治效果，筛选确定最佳除...为有效控制福建地区直播稻田禾本科杂草的危害，以莆田市仙游县游洋乡的水稻种植基地为试验点，选择测定1％噁嗪草酮悬浮剂、10％双草醚悬浮剂和20％氰氟草酯油悬浮剂等3种除草剂对稗草、千金子等禾本科杂草的防治效果，筛选确定最佳除草剂及其理想的田间使用浓度。结果表明：20％氰氟草酯油悬浮剂是防治直播稻田中稗草、千金子等禾本科杂草最佳的除草剂，田间推荐使用浓度为45～105 g · hm^ －2（有效成分）兑水675 L · hm ^－2，药后30 d防治效果达均可80.00％以上，无药害产生，对水稻安全。展开更多
基金Supported by Research Fund of the State Tobacco Monopoly Bureau(110201002002)the Open Research Project of Key Laboratory of Tobacco Genetics and Breeding in the Tobacco Industry(TB201006)~~
文摘[Objective] This study aimed to explore the effects of spores and crude toxins of Helminthosporium gramineum Rabenh f. sp. echinochloae（HGE） on the ac- tivity of defensive enzymes of barnyardgrass [Echinochloa crus-galli （L.） Beauv.]. [Method] The effects of spores and crude toxins of HGE, as well as the mixture of spores and crude toxins on the activity of defensive enzymes in barnyardgrass were determined under laboratory conditions. [Result] Spores and crude toxins of HGE had varying degrees of effects on PAL and POD activity, and no obvious effect on SOD activity in barnyardgrass. In addition, spores and toxins had some similar im- pacts on the defensive enzymes in barnyardgrass. [Conclusion] Since toxins have similar effects on the hosts as spores of fungal pathogen do, they can be a substi- tute for the fungal pathogen in studying the partial pathogenic mechanism of this pathogen due to its complexity in pathogenic process.
基金supported by the National Natural Science Foundation of China (31271999)the Special Fund for Agro-Scientific Research in the Public Interest, China (200903039-5)
文摘Rice false smut is caused by ascomycete Villosiclava virens, whose potential alternative hosts have been assumed previ- ously. Here its potential alternative hosts were surveyed and identified from 2008 to 2013 in the main rice-growing regions in China. Two common weeds in paddy fields, Digitaria sanguinalis Scop. and Echinochloa crusgalli （L.） Beauv., were found to present the similar symptoms to smut diseases in a few individuals in 2012 and 2013 in Zhejiang and Sichuan provinces of China, respectively. After the examinations of the spore morphology, their infection and extension mode in hosts, pathogen cell wall components, and molecular identification, the two pathogens were identified to be the Basidiomycetes, Ustilago syntherismae and Ustilago trichophora, respectively. So far there has been no alternative host of V. virens to be identified in China. These suggest that the alternative hosts of V. virens, if they do exist, are not possible to play an important role in the pathogen life cycle and the disease epidemics.
文摘为有效控制福建地区直播稻田禾本科杂草的危害，以莆田市仙游县游洋乡的水稻种植基地为试验点，选择测定1％噁嗪草酮悬浮剂、10％双草醚悬浮剂和20％氰氟草酯油悬浮剂等3种除草剂对稗草、千金子等禾本科杂草的防治效果，筛选确定最佳除草剂及其理想的田间使用浓度。结果表明：20％氰氟草酯油悬浮剂是防治直播稻田中稗草、千金子等禾本科杂草最佳的除草剂，田间推荐使用浓度为45～105 g · hm^ －2（有效成分）兑水675 L · hm ^－2，药后30 d防治效果达均可80.00％以上，无药害产生，对水稻安全。
