为了研制出对水稻移栽田一年生杂草防除效果优良且对水稻安全的除草剂品种,参照农药田间药效试验准则,采用稻田灌水整平后均匀甩施法开展了50%丙炔噁草酮·丁草胺·西草净乳油(EC)防除水稻移栽田杂草试验。试验结果表明,在有效...为了研制出对水稻移栽田一年生杂草防除效果优良且对水稻安全的除草剂品种,参照农药田间药效试验准则,采用稻田灌水整平后均匀甩施法开展了50%丙炔噁草酮·丁草胺·西草净乳油(EC)防除水稻移栽田杂草试验。试验结果表明,在有效成分推荐用量为600~900 g/hm2时,施药后40 d,50%丙炔噁草酮·丁草胺·西草净EC对一年生禾本科杂草稗草和多年生阔叶杂草野慈姑表现出良好的防除效果,而对一年生莎草科杂草萤蔺的防效一般。在试验过程中发现该除草剂品种900 g a.i/hm2以上的高剂量施用后对生长前期水稻具有轻微药害,但是施药5周后水稻生长恢复正常,对水稻产量没有明显影响。展开更多
Chlorpyrifos and dimethoate are overused agricultural pesticides that can trigger trophic cascades, resulting in toxicity to both terrestrial and aquatic organisms as well as altered ecosystems. In previous studies, s...Chlorpyrifos and dimethoate are overused agricultural pesticides that can trigger trophic cascades, resulting in toxicity to both terrestrial and aquatic organisms as well as altered ecosystems. In previous studies, substantial attention has been given to the effects of pesticides on vertebrate species and, to a lesser extent, species of zooplankton. The present study was designed to show that the fission time effective concentration in ciliates is a potential aquatic detection index for environmental monitoring. The ciliate Urostyla grandis was treated with doses of chlorpyrifos and dimethoate. After exposed to the pesticides, the LC_(50)(i.e., concentration that killed 50% of the ciliate cells within 24 h) values were 0.029 mg L^(-1) for chlorpyrifos and 0.0685 mg L^(-1) for dimethoate. The fission time effective concentrations after 168 h of exposure were 0.0075–0.0093 mg L^(-1) for chlorpyrifos and 0.2640–0.2750 mg L^(-1) for dimethoate. These results show that the fission time effective concentration is lower than the LC_(50) value in ciliates, indicating that fission time effective concentration is more suitable than the LC_(50) value for environmental monitoring using ciliates. The effects of chlorpyrifos and dimethoate on ciliate cell ultrastructures included agglutination of chromatin in the macronucleus, protruded and discontinuous macronuclear and micronuclear membranes, loss of integrity of mitochondrial membranes and contents, and abscission and deformation of the adoral zone of membranelles.展开更多
文摘为了研制出对水稻移栽田一年生杂草防除效果优良且对水稻安全的除草剂品种,参照农药田间药效试验准则,采用稻田灌水整平后均匀甩施法开展了50%丙炔噁草酮·丁草胺·西草净乳油(EC)防除水稻移栽田杂草试验。试验结果表明,在有效成分推荐用量为600~900 g/hm2时,施药后40 d,50%丙炔噁草酮·丁草胺·西草净EC对一年生禾本科杂草稗草和多年生阔叶杂草野慈姑表现出良好的防除效果,而对一年生莎草科杂草萤蔺的防效一般。在试验过程中发现该除草剂品种900 g a.i/hm2以上的高剂量施用后对生长前期水稻具有轻微药害,但是施药5周后水稻生长恢复正常,对水稻产量没有明显影响。
基金supported by the National Natural Science Foundation of China (Nos. 31601866 and 31501844)the Heilongjiang Province Colleges and Universities Youth Innovative Training Program (Nos. UNPYSCT2017178 and 2017180)
文摘Chlorpyrifos and dimethoate are overused agricultural pesticides that can trigger trophic cascades, resulting in toxicity to both terrestrial and aquatic organisms as well as altered ecosystems. In previous studies, substantial attention has been given to the effects of pesticides on vertebrate species and, to a lesser extent, species of zooplankton. The present study was designed to show that the fission time effective concentration in ciliates is a potential aquatic detection index for environmental monitoring. The ciliate Urostyla grandis was treated with doses of chlorpyrifos and dimethoate. After exposed to the pesticides, the LC_(50)(i.e., concentration that killed 50% of the ciliate cells within 24 h) values were 0.029 mg L^(-1) for chlorpyrifos and 0.0685 mg L^(-1) for dimethoate. The fission time effective concentrations after 168 h of exposure were 0.0075–0.0093 mg L^(-1) for chlorpyrifos and 0.2640–0.2750 mg L^(-1) for dimethoate. These results show that the fission time effective concentration is lower than the LC_(50) value in ciliates, indicating that fission time effective concentration is more suitable than the LC_(50) value for environmental monitoring using ciliates. The effects of chlorpyrifos and dimethoate on ciliate cell ultrastructures included agglutination of chromatin in the macronucleus, protruded and discontinuous macronuclear and micronuclear membranes, loss of integrity of mitochondrial membranes and contents, and abscission and deformation of the adoral zone of membranelles.
