杨树重要病害生物防治初探

自然界各种微生物生活在一起,成为复杂的群落。它们相互促进、制约,构成生物体的生态平衡。在森林病害防治中,利用益菌控制病菌的生存和活动,达到生物防治的目的。为了寻求这一新途径,在1982—1984年,对4种杨树重要病害进行了生物防治探索,从筛选和防病上作了研究。     

玉米田间作平菇研究

试验结果表明,内蒙古西部地区,玉米田间作平菇,在６月上旬至９月下旬是切实可行的。间作２００ｍ＾２平菇的玉米田产粮１５０ｋｇ,收鲜菇７３２．５ｋｇ,对照田产粮１２３ｋｇ,间作较对照增产２２％。     

L2 Controller Design for Nonlinear Systems with Dead- Zone Modification

An adaptive robust L2design method with dead -zone modification is proposed for a class of nonlinear systems with external disturbances and uncertain parameters. With priori knowledge of the bounds of the parametric uncertainties, the smooth projection method and the dead zone modification technology are incorporated into the adaptive laws to prevent parameter drifting and reduce the computation burden. The number of parameter estimates is minimal for the adaptive system. The algorithm can guarantee the tracking errors asymptotically converge to the desired dead zone if the external disturbances are zero. The system satisfies L2 disturbance rejection criterion when the external disturbances are considered.     

文昌鸡生态放养过程中驱虫程序的研究

采用虫卵漂浮法、麦克马斯特氏虫卵计数法对文昌鸡生态放养期间感染寄生虫的种类与粪便中虫卵数量进行监测。结果表明,文昌鸡生态放养感染的寄生线虫主要为鸡蛔虫和几种异刺线虫。自然条件下生态放养35 d后,每克粪便中寄生虫虫卵数（eggs per gram, EPG）达到了700,呈显著增长趋势。抽样宰杀30只鸡,检出18只感染鸡蛔虫成虫,感染率为60％,平均感染强度为8条/只。因此,建议整个生态放养期间驱虫3～4次为宜,首次驱虫时间为放养后25～30 d。     

农业科技成果产业化的影响因素及其对策的分析

从内蒙古自治区农业科技现状出发，简要分析了影响农业科技成果产业化的６个因素，并提出了实现农业科技成果产业化的５项对策。     

The potential protective value of ants in Northern Australian coffee plantations

Abstract

Native ants are the oldest example of biological control agents used in tropical tree crops. Unfortunately, intensification of agricultural practices has led to a simplification of habitat and subsequent loss of native ant biodiversity. This article describes research that evaluated the native and introduced ants present in the canopies of two Australian sun coffee plantations, their distribution pattern and their potential to limit pests. The presence in coffee plantations of a range of beneficial insects and parasites, plus the effect of ants, most notably Iridomyrmex suchieri Forel, may maintain potential pests at low levels in coffee plantations. These effects may be important for future biological control programs of coffee pests in Australia, although the sun coffee grown here does not harbor a large variety of canopy ant species.     

覆土有益微生物灭活菌体和无菌过滤液对蘑菇菌丝体生长的影响

研究覆土有益微生物的灭活菌体和无菌过滤液对蘑菇菌丝生长的影响,结果二者均有一定的刺激作用。相比之下,过滤液作用时间发生较早、作用强度大,灭活菌体作用时间发生较晚,作用强度小。     

冲天柏育苗试验结果分析

采用切根及喷云大-120 对冲天柏苗木生长的效果进行了试验, 结果表明: 切根和喷云大- 120 处理对冲天柏苗木的生长作用一般不显著, 在苗高、地径、冠幅等10 个性状中, 仅喷云大- 120 对主根发育影响显著,对侧枝数的发育呈负作用, 故在冲天柏育苗中不宜采用切根和喷云大-120 作技术处理。     

2000-2004年黑河流域生态调水

黑河流域是河西走廊和内蒙古高原西部著名的粮仓和绿洲。随着气候和人类活动等各种因素的影响,特别是中下游地区水资源配置严重失衡,导致下游荒漠化和沙漠化日趋严重,生态环境急剧恶化,下游额济纳地区已成为我国北方地区沙尘暴的沙源地之一,危害之广,波及西北、华北,乃至更广大地区。对此,党中央、国务院十分重视,多次指示加强管理,治理黑河。从2000年开始一场以水资源合理配置为核心的黑河干流水量统一调度以及流域综合治理全面启动,本文主要阐述2000-2004年水量调度情况,对中下游地区调度前后水文、气象资料作对比分析,以期引起社会各界了解、重视,进一步做好黑河水量统一调度工作和水文监督、监测工作。     

Activity,molecular mass and hydrolysis on baker's yeast protein of extracellular proteases from the putative probiotic bacteria Microbacterium sp. strain 8L and Exiguobacterium mexicanum strain 8N

The bacteria Microbacterium sp. 8L and Exiguobacterium mexicanum 8N are known to improve the culture of Artemia franciscana using baker's yeast as food. Using spectrophotometry, sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE), substrate‐SDS‐PAGE and pH‐stat in vitro‐digestibility assays, the activity, molecular mass and hydrolysis on baker's yeast protein of proteases from extracellular polymeric substances (EPS) of the strains 8L and 8N along with the pathogenic strains Microbacterium sp. 8R and Vibrio parahaemolyticus 588 CECT (Vp) were studied. The EPSs of 8L and 8R showed one activity band, on which the serine inhibitor phenylmethylsulphonyl fluoride (PMSF) had no effect. The EPSs of 8N showed four bands; two were unaffected by PMSF, whereas one was affected, and the other was partially affected. The EPSs of Vp showed two bands, one partially inhibited by PMSF. No inhibitory effects from 1‐chloro‐3‐tosylamido‐7‐amino‐2‐heptanone (trypsin inhibitor) were observed in the protease bands of the studied bacteria. The EPSs of 8L and 8N showed a similar degree of hydrolysis (pH‐stat). The EPSs of 8L had the lowest Dice index of similarity of yeast protein profiles at 1 h of reaction. We conclude that the strain 8L could benefit A. franciscana by providing bacterial proteases for digestion of baker's yeast.