施氮磷钾对赶黄草产量和槲皮素含量的影响

为了研究N、P、K对赶黄草生长发育、产量和槲皮素含量的影响,为赶黄草的合理施肥提供理论依据.采用N、P、K三因素二水平完全试验设计,分析不同处理药用有效成分槲皮素含量.结果表明,施N极显著提高产量,N明显增加植株分枝和根的重量,施P有增加植株高度的效应,施K对提高植株槲皮素含量有一定影响.因此,N是影响产量的主要因素,增施N肥,配施P、K肥是提高赶黄草产量、增加槲皮素含量和积累量的有效施肥措施.     

Effect on Yields of Fresh Ear in Fresh-eating Glutinous Maize and Synthesis Evaluation on Economic Benefit in Different Cultivated Mode

试验表明,种植鲜食糯玉米采用方块营养土薄膜保温育苗带土定向移栽的全膜覆盖栽培比露地直播鲜穗平均单产增加47.79%;其经济效益综合评价排名第一。它能提早播种季节,错开销售旺季和延长供应季节,增加鲜穗产量,提高经济效益,为农民开辟了一条创收新途径。     

哀牢山地农作物物候期和产量随高度与坡向的分布特征

根据哀牢山东西坡农业考察资料并结合该山地气候资料，研讨山地农作物物候期和产量随海拔高度与坡向的分布特征。     

Type and time of autumn tillage with and without herbicides at reduced rates in southern Sweden: 1. Yields and weed quantity

Environmental as well as economic incentives support the use of integrated weed management (IWM) systems for crop production. In order to reduce the input of agrochemicals for weed control, it may be possible to combine reduced doses of herbicides with appropriate tillage strategies and still maintain acceptable weed population levels. The purpose of this study was to compare the efficiency of different tillage strategies, with and without herbicides at 50% of normal rates, on weed populations and crop yields. The influences of type and time of stubble cultivation, harrowing and mouldboard ploughing were followed in eight long-term field trials in southern Sweden from 1988 until the spring of 1994. The crop rotations were dominated by spring-sown oats (Avena sativa L.) and barley (Hordeum distichon L.). Although significant site-by-year-by-treatment interactions were found, certain trends in influences of tillage on weeds and yields were identified. Weed density and weight often decreased in the order: stubble cultivation without ploughing > solely ploughing > stubble cultivation succeeded by ploughing. Grain yields of oats and barley varied 6–50% among tillage systems and the highest yields were often obtained in plots where ploughing succeeded stubble cultivation. Effects of tillage on weeds or yields were usually not influenced by herbicide application. Although only subnormal herbicide rates were used, weed density and weight were mostly reduced by 70–90%, while yields increased by 10–20%. In the spring of 1994, 1 year after the last herbicide application, densities of annual broad-leaved weeds were 40–65% lower in plots previously treated by herbicides than in non-treated plots, and differences among tillage systems were still significant. This study shows the advantage of combining herbicides at reduced rates with stubble cultivation and ploughing.