[Objective] To effectively suppress weeds and degrade pesticide residues in soil, pollution-free agricultural production is a very important way. [Method] In regions where high residual pesticides had been applied for...[Objective] To effectively suppress weeds and degrade pesticide residues in soil, pollution-free agricultural production is a very important way. [Method] In regions where high residual pesticides had been applied for a long term, 2-3 consecutive years of shallow ploughing after the autumn harvest, early shallow ploughing and sowing later in the next spring, and late ploughing and sowing were conducted,and the effects of the three measures on weed suppression and reduction of pesticide residue in soil were analyzed by measuring the length and fresh weight of crop radicles. [Result] Trifluralin applied in the A. membranaceus field for a long term limited the growth of the alfalfa seedlings. That is, the radicle length of each plant was 2.1-2.9 cm shorter than that of the control, and the fresh weight of each plant reduced by 0.19-0.20 g. Metsulfuron methyl applied in the alfalfa field for a long term also limited the growth of the alfalfa seedlings, that is, the radicle length of each plant was 1.9-2.0 cm shorter than that of the control, and the fresh weight of each plant reduced by 0.13-0.15 g. Shallow ploughing was conducted within two days after the autumn harvest, and all weed seeds on the ground were plowed into the plough layer 0-10 cm instead of deep soil. Early shallow ploughing in the next spring could make most seeds of weeds in surface soil sprout early, and sowing was conducted after 10 d, so that about 40% of weeds sprouting early were killed off. However, after shallow ploughing and sowing were conducted 10 d later than the normal sowing period, and around 30% of weeds were killed off. In addition,the weeds left in soil should be removed manually at the seedling stage or in late period. These measures had no adverse impact on the growth and development of crop radicles and yield. [Conclusion] In regions where pesticides with long-term residue had been applied for a long term, 2-3 consecutive years of shallow ploughing after the autumn harvest, different farming and sowing measures and artificia weeding could suppress weeds in the crop fields effectively, did not pollute soil environment, and promoted the degradation of pesticides left in soil.展开更多
文摘[Objective] To effectively suppress weeds and degrade pesticide residues in soil, pollution-free agricultural production is a very important way. [Method] In regions where high residual pesticides had been applied for a long term, 2-3 consecutive years of shallow ploughing after the autumn harvest, early shallow ploughing and sowing later in the next spring, and late ploughing and sowing were conducted,and the effects of the three measures on weed suppression and reduction of pesticide residue in soil were analyzed by measuring the length and fresh weight of crop radicles. [Result] Trifluralin applied in the A. membranaceus field for a long term limited the growth of the alfalfa seedlings. That is, the radicle length of each plant was 2.1-2.9 cm shorter than that of the control, and the fresh weight of each plant reduced by 0.19-0.20 g. Metsulfuron methyl applied in the alfalfa field for a long term also limited the growth of the alfalfa seedlings, that is, the radicle length of each plant was 1.9-2.0 cm shorter than that of the control, and the fresh weight of each plant reduced by 0.13-0.15 g. Shallow ploughing was conducted within two days after the autumn harvest, and all weed seeds on the ground were plowed into the plough layer 0-10 cm instead of deep soil. Early shallow ploughing in the next spring could make most seeds of weeds in surface soil sprout early, and sowing was conducted after 10 d, so that about 40% of weeds sprouting early were killed off. However, after shallow ploughing and sowing were conducted 10 d later than the normal sowing period, and around 30% of weeds were killed off. In addition,the weeds left in soil should be removed manually at the seedling stage or in late period. These measures had no adverse impact on the growth and development of crop radicles and yield. [Conclusion] In regions where pesticides with long-term residue had been applied for a long term, 2-3 consecutive years of shallow ploughing after the autumn harvest, different farming and sowing measures and artificia weeding could suppress weeds in the crop fields effectively, did not pollute soil environment, and promoted the degradation of pesticides left in soil.
