慎用对后茬作物有影响的除草剂

使用除草剂防除作物田间杂草是夺取丰收的重要措施,但是,有一些除草剂在土壤中分解速度慢,残留期长,容易对后茬作物产生影响,应谨慎使用.     

From red to green: Cuba forced to conserve due to economic crisis

The most severe economic crisis in post-revolutionary Cuba has forced the country to adopt an austere conservation program. Resource-wise measures have been instituted in the energy, transportation, housing, and agricultural sectors because of a rapid drop in Soviet aid, significant loss of trade with the Eastern Bloc, a halving of oil imports in a one-year period, and stepped-up U. S. sanctions. The economic crisis is also causing negative environmental impacts, in part because pollution abatement projects have been deferred and the tourism industry is being developed to bring in hard currency. However, it is anticipated that many environmentally-sound initiatives will help Cuba through the crisis and will remain in place.     

烟蚜茧蜂繁育及对烟蚜的防治效果探索

进行了人工温室大量繁殖烟蚜茧蜂和田间释放烟蚜茧蜂试验研究。结果表明,接蜂时烟蚜量和接蜂量是影响僵蚜繁殖量的重要因素;大田放蜂生物防治效果达89.3%,防治效果显著;大田放蜂应在田间蚜量很少的5月中旬,同时防治效果随着放蜂次数和放蜂量的增多,防治效果越来越好。     

加快家族企业向现代企业的转变

家族制制约着民营经济的进一步发展。为促进民营经济可持续发展，我们必须加快家族企业向现代企业的转变。一方而，必须改革产权制度，实现自然人产权制度向法人产权制度的转变;另一方而，必须改革管理制度，实现投资人管理模式向职业经理人管理模式的转变。     

夏玉米如何合理施肥

夏玉米是华北平原及黄淮海平原主要栽培作物之一,合理施肥是夏玉米生产中的关键,就夏玉米如何合理施肥进行了分析。     

气候变化对我国农业影响的研究进展

综述了全球气候变化对我国农业的影响。气候变化直接影响农业湿地作物产量,使水稻产量减少;CO2浓度的增加既有利于作物生长,又会抑制利于作物生长的其他因素;紫外线增多直接使作物产量降低、蛋白质和脂肪减少;气候变暖会影响我国的农业气候条件和种植制度、作物品种的布局、产量、施肥水平;气候变暖将使江河水量、水资源的供需状况、旱涝灾害出现的频率、水质等发生变化,从而影响农业。