蟛蜞菊化学防治研究

利用两种常用的除草剂草甘膦和克无踪对野外及盆栽的蟛蜞菊进行杀灭试验，结果表明：利用克无踪杀灭蟛蜞菊用药量少．见效快．克无踪200倍液对蟛蜞菊有较好的抑制效果，但药效期短，对蟛蜞菊起不到彻底防治的作用；草甘膦药效慢但持久，100倍以上的浓度对蟛蜞菊有较好的控制作用，是防治蟛蜞菊的适合药剂。     

You are what you eat: native versus exotic Crotalaria species (Fabaceae) as host plants of the Ornate Bella Moth,Utetheisa ornatrix (Lepidoptera: Erebidae: Arctiinae)

Crotalaria plants and Utetheisa ornatrix are closely linked to each other: the larvae destroy the seeds, while the moth depends on hostplants for alkaloids. To better understand the ongoing co-evolution, the present study examines how native hostplants compare to exotic ones. Leaf-feeding on Crotalaria pumila, C. rotundifolia, and C. incana, native to the moth’s range, led to faster larval development than on the exotic C. lanceolata, C. spectabilis, and C. pallida. Seed-feeding on all species of Crotalaria led to accelerated larval development and a resultant larger adult moth, and correlates with a higher nitrogen content in the plant tissues. These results add a novel dimension to the previous studies of reproductive biology of this model organism. In controlled settings, mature larvae showed preference for leaves of C. spectabilis over those of other species, perhaps due to the higher alkaloid content. Differences in morphology and phenology of Crotalaria determine the ecology of U. ornatrix populations in Florida. The introduction of novel hostplants, on which U. ornatrix can have a significant negative effect and which are of concern to humans as invasive toxic weeds, has greatly expanded the niche occupied by this moth. Possible co-evolution of Utetheisa sensu lato and plant defences in the genus Crotalaria is discussed.     

Gene flow from genetically modified herbicide-resistant rapeseed to cruciferous weeds

The sexual compatibility between genetically modified (GM) glyphosate-resistant rapeseed variety Q3 (Brassica napus L.) and 5 cruciferous weeds is studied through the observation of fluorescence microscopy and cross-fertility after manual pollination. The results indicated that Q3 (as male) was highly incompatible with Thlaspi arvense L., Capsella bursa?pastoris (L.) Medic, Cardamine hirsuta L. and Rorippa palustris (L.) Besser (as female). Fluorescence microscopic observation showed that growing of pollen tubes terminated on the stigma surface or at the upper 1/3 part of the style. However, B. juncea×Q3 was compatible, and the compatibility index was 1.65. Under the neighboring growth and natural pollination conditions, the rates of gene flow from Q3 to T. arvense, C. bursa-pastoris, C. hirsute and R. palustris were all 0, while it was 0.86% for B. juncea. These results indicate that there is difference in the rate of gene flow between GM rapeseed and cruciferous wild weeds, and frequency of gene flow is highly correlated with sexual compatibility.     

湘潭市郊冬季菜地生态系统杂草植物群落物种多样性的研究

对湘潭市郊菜地生态系统冬季期间杂草植物群落的物种多样性进行了初步研究，共出现18种，分属于10科15属，物种丰富度为9-15；Simpson指数为0.6401-0.7451；Shannon-Wiener指数为1.4852-1.7000；均匀度指数为0.5791-0.7145。结果表明：离市中心越远，物种多样性程度越高。     

甘肃省农田杂草区划

根据调查资料,自然条件和各地耕作栽培特点,把我省农田杂草划分成六个草害区。河西灌溉农业草害区主要杂草有藜、野燕麦、田旋花等;陇中黄土丘陵旱作农业草害区主要杂草有猪殃殃、苣荬菜、日本田箭等;洮岷高寒阴湿草害区主要杂草有细穗密花香薷、刺儿菜、萹蓄等;陇南山地农业草害区主要杂草有播娘蒿、繁缕、麦瓶草等;陇东黄土高原旱作草害区主要杂草有雀麦、离子草、狗尾草等。明确了各地主要杂草种类与危害,为制定化学防除策略提供了依据。     

不同种植模式对补骨脂生长及其产量的影响

以补骨脂为试验材料,研究三种种植模式对补骨脂生长及其产量的影响。通过对补骨脂大田生育期、相关农艺性状、叶绿素含量、种子产量指标的测定和分析,结果表明:三种种植模式对补骨脂的生长发育和产量均有显著影响,其中,宽垄双行-两边地膜覆盖-中间稻草覆盖种植模式的综合表现最好,农艺性状表现为株高整齐,茎围粗,有效叶片多,长势强,抗倒伏,产量居于试验产量的第一位166.33 kg/667m2,较对照多40.63 kg/667m2,增产极显著,比较适合西昌地区补骨脂的生产栽培。     

水稻栽培新途径稻克草技术栽培措施的多因素分析

证实以高产优质高效为目的的水稻栽培新途径稻克草技术的科学性。优选出稻克草栽培技术的主要技术措施，对常规水稻栽培的行株距，轩数，施肥法，除草情况和水稻品种进行多因素多水平正交试验，得出了稻克草栽培技术措施的最佳组合和科学性，并在多重复对比试验中得到验证。     

一枝黄花属三种欧洲入侵种的生态学研究概况

北美一枝黄花(Solidago altissima)、巨大一枝黄花(Solidago gigantean)和狭叶一枝黄花(Solidago graminifolia)原产北美,于19世纪中叶在欧洲归化并成为外来入侵种。简述这3个种的种群扩张动态、侵占速率的基本模型、当前分布区域及潜在生长域的预测等种群生态学方面的研究内容,并介绍一枝黄花属入侵种在中国的分布情况及基本生物学特性。以借鉴国外对一枝黄花属植物的研究方法和手段,帮助我们理解该植物成功入侵的原因并预言一枝黄花属在我国的入侵植物的未来扩张趋势,对开展它们的综合治理有重要的意义。     

基于杂草改进的模糊聚类雷达信号分选

针对雷达辐射源信号参数严重混叠、聚类数目未知等问题,提出一种基于入侵性杂草优化模糊聚类的智能算法,该算法无需事先设定聚类数目,而是在整个数据集的属性空间内并行搜寻最佳的聚类数目和聚类中心,具有结构简单、鲁棒性好的特点。将此方法应用到雷达信号的分选当中,并与传统的K均值算法及AP聚类算法进行对比,实验结果验证了该算法的有效性。     

不同除草剂对谷子田杂草的防除效果

探讨了2,4-D丁酯、扑草净、单嘧磺隆对谷子田杂草的防除效果,田间试验结果表明:扑草净质量浓度为1 200 g/hm2的防效超过80%,为防除马齿苋的最佳除草剂处理;扑草净质量浓度为1 200g/hm2和单嘧磺隆质量浓度为600 g/hm2的防效超过80%,为防除反枝苋的最佳除草剂.