生物多样性在害虫控制中的生态功能与机理

生态学的有害生物治（EBPM）或生态管理（EPM）是新世纪农业有害生物防治的新对策。应用系统工程的原理和方法改变农田生态系统生物多样性,进行害虫生态控制将越来越受到人们的重视。通过农田生态系统生物多样性、调节农田生态系统多样性对天敌和害虫的影响以及生物多样性控制害虫的机制及生物多样性在害虫生态控制中的利用前景4个方面,论述农田生态系统生物多样性在害虫控制中的生态功能与机理。     

施用蝗虫微孢子对草原地上部分天敌群落多样性的影响

为明确蝗虫微孢子对蝗虫的持续控制,2015年在青海省开展了蝗虫微孢子防治草原蝗虫的试验和连续跟踪调查。结果表明,施用蝗虫微孢子前后温性和高寒草原蝗区天敌种类无明显变化,但部分天敌类群所占比例发生了变化,施用蝗虫微孢子2、3、4周后,温性草原中寄生蝇所占比例分别显著增加了330.6%、752.8%、752.8%,高寒草原中寄生蝇所占比例分别显著增加了108.1%、309.9%、310.8%,温性草原中芫菁所占比例分别显著下降了43.5%、45.5%、75.5%,高寒草原中芫菁所占比例分别显著下降了54.2%、77.2%、76.3%。施用蝗虫微孢子2、3和4周后,温性草原的Shannon指数比防治前分别显著增加了5.7%、7.0%、3.8%,Pielou指数比防治前分别显著增加了6.2%、6.2%、3.7%,Simpson指数比防治前分别显著增加了5.4%、6.8%、4.1%;施用蝗虫微孢子2周后,高寒草原的Shannon指数、Pielou指数和Simpson指数比防治前分别显著升高了4.8%、5.4%、3.8%,施用3周后,3个天敌群落多样性指数比防治前分别增加了1.8%、1.3%、2.2%,但Shannon指数和Simpson指数与防治前无显著差异,而Pielou指数比防治前显著增加,施用4周后,3个指数均与防治前无显著差异。施用蝗虫微孢子2、3和4周后,天敌群落布雷柯蒂斯距离与防治前差异显著,而重复样区间的布雷柯蒂斯距离在整个调查期无显著变化。表明蝗虫微孢子施用后对不同生态类型草原天敌群落多样性有一定的保护作用。     

极端干旱区垂直线源灌方式对葡萄生长及水分利用效率的影响

灌溉方式对根系湿润方式的不同会影响作物生长及其对水分的利用效率。以常规滴灌方式为对照,通过田间试验研究了垂直线源灌方式对葡萄生长和水分利用效率的影响,结果表明:葡萄生育关键期灌水前后垂直线源灌方式根层土壤平均含水率可达到田间持水率的75.1%和82.8%,常规滴灌方式为田间持水率的60%和72%;垂直线源灌条件下净光合速率,蒸腾速率,气孔导度均较常规滴灌高,净光合速率均经历了气孔限制和非气孔限制,其中由水分胁迫引起的非气孔限制,垂直线源灌晚于常规滴灌出现,且表现不明显;垂直线源灌方式在地上生物量生长方面略好于常规滴灌方式,但两者未表现出明显差异;垂直线源灌方式较常规滴灌方式在产量上提高了1.2%;叶片水平上的水分利用效率,垂直线源灌方式较常规滴灌方式提高了57.4%。     

The role of models for multicriteria evaluation and multiobjective design of cropping systems for managing weeds

Weeds are both harmful for crop production and important for biodiversity, while herbicides can pollute the environment. We thus need new cropping systems optimising all cultural techniques, reconciling agricultural production, herbicide reduction and biodiversity conservation. Here, we show how to (i) develop models quantifying the effects of cropping systems on weed dynamics, (ii) integrate interactions between weeds and other organisms, (iii) predict the impact on production and biodiversity and (iv) use the model for multicriteria evaluation and multiobjective design of cropping systems. Among the existing weed dynamics models, we chose the one closest to our requirements to illustrate these different steps, that is, FlorSys which predicts multispecific weed dynamics as a function of cultural techniques and pedoclimate. We have illustrated the development of interaction submodels with the example of a crop pathogen whose propagation is increased when infecting grass weeds. To evaluate the weed flora impact, predicted weed densities were translated into indicators of harmfulness (crop yield loss, technical harvest problems, harvest pollution, field infestation, crop disease increase) and biodiversity (weed species richness and equitability, trophic resources for birds, insects and pollinators). Simulations were run over several years and with different weather scenarios (i) to optimise cultural techniques to control harmful weeds, (ii) to analyse the impact of changing agricultural practices (e.g. simplified tillage and rotations, no‐till, temporary crops) on weed density, species and trait composition and (iii) to evaluate cropping systems for their ability to reconcile agricultural production and biodiversity, thus identifying levers for designing sustainable cropping systems.     

伊犁地区5个引种白蜡对干旱胁迫的响应

为探讨伊犁地区5个引种白蜡的抗旱性差异,为区域化推广栽培提供理论依据,以5个3a生引种白蜡苗木为材料,采用盆栽控水试验方法,设置4个水分梯度(CK、T1、T2、T3,田间持水量分别为80％～85％、55％～60％、40％～45％、30％～35％),测定其SOD活性、POD活性、MDA含量、脯氨酸含量、可溶性蛋白含量、叶...     

Effects of weed control practices on surface-dwelling arthropod predators in tomato agroecosystems

Weed control, an important practice in agroecosystems to protect crop production, is usually achieved with herbicides. However, these pesticides are expensive, pose potential risks to the environment, may affect some beneficial organisms indirectly, and decrease overall arthropod biodiversity, including pests and their natural enemies, by removing weeds that might act as hosts or shelters for many organisms. The activity density response of important surface-dwelling arthropod predators (ground beetles [Coleoptera: Carabidae], ants [Hymenoptera: Formicidae] and spiders [Arachnida: Araneae]) to herbicides (trifluralin and paraquat), and to two alternative weed management practices (rye straw mulch and mechanical treatment to maintain weeds below threshold levels, in comparison with an untreated check), was assessed using pitfall traps. The mulch treatment had the greatest effect on activity density, reducing the number of predators trapped significantly (P<0.05). Herbicide use resulted in significant (P<0.05) reductions in the activity density of ground beetles. Most predators were trapped in the check plots — which had the highest weed biomass, followed in turn by numbers trapped in the threshold weed control treatment, the full herbicide application and the mulch treatment plots. http://www.phytoparasitica.org posting July 10, 2002.     

中国步甲属（鞘翅目：步甲科）物种多样性及其保护问题

步甲属是步甲科昆虫中的一个大属,其以体形大(相对于步甲科昆虫)、体态优美、色彩艳丽而著称。步甲属昆虫多生活于森林中,以蚯蚓、蜗牛等为食,与环境关系密切,在作为生物多样性指示物方面有一定的应用前景。我国步甲属种类非常丰富,且特有成份高。目前已知约410种,其中特有种为324种,占79．02％;在分布于我国的46个亚属中,18个为特有亚属,特有率为39．1％。本文在分析中国步甲属物种多样性及其特点的基础上,对这一类群的研究和保护问题提出了建议。     

鸭病毒性肝炎病毒JH2株感染雏鸭血清生化指标的动态变化

用1型鸭肝炎病毒山东分离株JH2人工感染3日龄健康樱桃谷雏鸭,对接种后1～5 d的血清酶、血糖及血脂等多项血清生化指标进行测定,结果表明:鸭肝炎病毒感染雏鸭1～2 d内丙氨酸氨基转移酶、天门冬氨酸氨基转移酶活性较未攻毒的对照组极显著升高:碱性磷酸酶活性在接种后2～3 d内与对照组差异极显著;接种后1～5 d攻毒组总胆红素和间接胆红素的含量均低干对照组,其中接种后1、3、4 d时差异显著;攻毒组胆碱脂酶和甘油三脂在接种后1～2 d内较对照组极显著升高,胆固醇在整个试验中无明显变化;谷氨酰胺转移酶活性在接种后1～4 d内较对照组有极显著升高;乳酸脱氢酶活性1～3 d内较对照组极显著升高,而肌酸激酶活性虽高于对照组,但差异不显著;雏鸭在接种后1～3 d内表现出明显的低尿酸血症,接种后1 d肌酐含量较对照组显著升高;α-淀粉酶活性呈逐渐升高的趋势,但均低于对照组,接种后1～2d与对照组差异极显著:攻毒组总蛋白、白蛋白和球蛋白在整个试验期间表现为先升高后降低的趋势,血清葡萄糖在接种后1 d降至最低,与对照组差异极显著.     

“果畜结合”生态果园调查报告

果畜结合是改善洛川县果园土壤有机质含量低、土壤肥力不足,提高苹果产量和质量有效途径。     

乳酸锌对断奶肉兔生长性能、肠道发育和血清生化指标的影响

本试验旨在研究饲粮中添加乳酸锌对断奶肉兔生长性能、肠道发育和血清生化指标的影响.选择28日龄同期断奶新西兰兔420只,随机分为5组:对照组(饲喂基础饲粮,饲粮中添加硫酸锌形式的锌0 mg/kg)、硫酸锌组(在基础饲粮中添加硫酸锌形式的锌80 mg/kg)以及3个乳酸锌组(在基础饲粮中分别添加乳酸锌形式的锌20、40、8...