改制毛竹林害虫虫情变动的探讨

改制前的毛竹林，每两年有一年无笋或少有笋、有几个月林内立竹上无叶，竹子上的害虫种类简单，危害不重，有些害虫少发生或不能发生；能发生或危害重的竹子害虫，在生活过程中，习性多少都发生一些变化，如竹织叶野螟有迁飞习性，毛笋泉蝇、毛竹黑叶蜂部分蛹有滞育习性，赭翅双叉端环野螟有同时以小幼虫和老熟幼虫越冬习性，以适应无笋、少叶的营养环境。改制后的毛竹林地被物挖锄，天敌资源锐减，竹林中年年有笋，立竹上终年披叶，使竹子害虫食物条件改善，竹子害虫种类逐年增加，害虫迁飞、滞育习性的比例逐年减少，危害逐年加重。     

漯河市园林植物主要刺吸类害虫及综合防治技术

漯河市17科25种园林植物主要刺吸类害虫，阐述其综合防治技术，以期达到对刺吸类害虫“预防为主、科学防控”的目标。     

广东南岭国家级自然保护区大东山昆虫名录(VI)

本文报道广东南岭国家级自然保护区大东山管理站所辖林区半翅目蝽科1种,鞘翅目豉甲科7种、瓢虫科1种,鳞翅目螟蛾科48种,双翅目虻科1种、寄蝇科35种,膜翅目蚁科41种,共134种。     

杨树生理特性及生态因子与抗蛀干害虫的关系

在研究了大量文献的基础上，探讨了杨树抗蛀干害虫研究的现状、抗虫机制、机理，分析了杨树外部形态学、解剖学、生理生化特性及生态因子与抗蛀干害虫性的关系，找出了存在的问题，提出了抗虫育种的新见解。     

大豆害虫天敌昆虫的研究概况

根据近年来的研究现状，对大豆害虫天敌昆虫的研究概况进行了综述，并对其发展趋势加以展望，以期为广大农业，植物保护工作者提供参考。     

散装小麦局部环流熏蒸杀虫实仓试验

针对小麦仓中下层局部生虫，采用粮堆局部处理机环流熏蒸，分两次投药，共计熏蒸处理时间为两周。实验证明：在处理部位PH3浓度100～300ppm可以保持12天左右，粮堆中的害虫全部杀死；经检查埋入粮堆的赤拟谷盗、谷蠹和玉米象，成虫死亡率100％，对虫粮培养42天后，检查F1代为零。     

磷化氢环流熏蒸技术在高大房式仓中的应用

在高大房式仓中进行了磷化氢环流熏蒸试验，同时研究了不同仓型和不同熏蒸方式存在的差异。结果表明，在仓房容量、风道设置、环流设置配置合理的条件下，能在较短时间内使磷化氢气体在仓内各部位分布均匀，最低浓度与最高浓度比值最小为0．5，大部分比值在0．8－0．9之间，均高于国外资料推荐的PH3环流熏蒸浓度均匀性标准，即大于0．25。保持有效杀虫浓度的时间长，能够杀死仓内粮堆中的储粮害虫，取得了良好的杀虫效果。     

Control of preharvest aflatoxin contamination in maize by pyramiding QTL involved in resistance to ear-feeding insects and invasion by Aspergillus spp.

Several resistance sources and resistance mechanisms to aflatoxin formation and corn earworm (Helicoverpa zea Boddie) damage to maize (Zea mays L.) have been identified. Based on this knowledge, experiments were initiated toward achievement of the following objectives: (1) to confirm earlier determinations on resistance traits of germplasm sources and to identify quantitative trait loci (QTL) associated with each of the traits, and (2) upon estimation of the degree of QTL effects on each trait, to generate a maize population, with chemical and physical resistance to Aspergillus spp. and ear-feeding insects, for inbred development. A 2-year field experiment to evaluate selected genotypes inoculated with A. flavus and infested with corn earworm revealed that significant variation exists among the genotypes for aflatoxin contamination and corn earworm damage. The protection of maize ears against aflatoxin contamination was primarily dependent on resistance to fungal infection and ear-feeding insects, and excellent husk coverage and tightness. A major QTL (p1) identified on chromosome 1S had effects of 54.0, 42.1, and 28.3% on the phenotypic variability for concentrations of silk maysin, 3′-methoxymaysin+apimaysin, and chlorogenic acid, respectively. Markers/QTLs for husk phenotypic traits and total aflatoxin concentrations have been determined, but more detailed mapping of these chromosomic regions will be necessary to locate precise markers/QTLs for husk traits and aflatoxin production. Realizing the complexity of the Aspergillus–aflatoxin-maize system and the factors affecting aflatoxin contamination, we are directing our program toward marker-assisted breeding to enhance or improve general genetic resistance to ear-feeding insects and invasion by Aspergillus spp.     

Recurrent selection for maysin, a compound in maize silks, antibiotic to earworm

A thorough knowledge of the inheritance of maysin, a flavone glycoside with antibiosis to corn earworm, Helicoverpa zea Boddie, in the silks of maize will assist breeders in choosing the most efficient method of incorporating this trait into elite inbreds. Two breeding populations, one having exotic origin (EPM), the other from southern inbred lines (SIM) were subjected to six cycles of recurrent selection for increased silk maysin. Ten per cent of the individuals evaluated in populations were selected for recombination as S₁ progenies in each cycle. Progress was evaluated as C0 to C6 population cycles in a randomized complete‐block experiment with five replications in 1997 and 1998. Maysin fresh weights in silks of the C0 populations were 0.54% for EPM and 0.36% for SIM. Responses of 0.19% per cycle in EPM and 0.22% per cycle in SIM resulted in an EPM (C6) population with 1.76% maysin and an SIM (C6) population with 1.69% maysin. Silk maysin concentrations above 0.2% begin to substantially reduce larval growth and prevent completion of the life cycle when husk coverage is sufficient to force the insect to feed on silks while entering the ear. Chlorogenic acid and two analogues of maysin, apimaysin and 3′‐methoxymaysin, were found in such minor quantities in silks that they could not be credited with any impact on antibiotic activity against the insect. Selection has effectively increased silk maysin concentration in both EPM and SIM. Trait responses for maysin are highly heritable and will allow the plant breeder to introgress resistance to the corn earworm into elite material easily.