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81.
《蒙古秘史》中的野生食用植物研究 总被引:7,自引:1,他引:6
哈斯巴根 《干旱区资源与环境》1996,10(1):87-96
经考证,在《蒙古秘史》中的植物古蒙古名称中,有山荆子、稠李、地榆、鹅绒委陵菜、葱、山韭、山丹和野韭等8种野生食用植物。植物区系及地理分布的研究表明,这些植物在十二世纪蒙古人所采集的地点,即现在的蒙古国肯特山脉地区仍有广泛分布。从民族植物学的研究看,它们在蒙古族民间被用于代粮、野菜、茶用、药用和调味品,比过去的利用有了很大的发展,已成为独特的植物利用文化。本文不仅对蒙古学研究能够提供可靠的依据,而且对寻找新的食用植物种类及其开发利用研究也提供了一些基本资料。 相似文献
82.
张方明 《甘肃农业大学学报》1996,(2)
通过对博士研究生特点的综合分析,在教学实践中强化三个主要环节,探索了适合博士生特点,反映课程要求的教学方法。 相似文献
83.
Alba Marina Cotes Philippe Lepoivre Jean Semal 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(5):497-506
An experimental protocol consisting in the colonisation of pregerminated bean seeds dressed withTrichoderma sp. was used in order to study the mechanisms correlated with the protective effect againstPythium splendens. Seed dressed with TH-11 (T. koningii) for 24 h presented a higher protective effect and a higher level of seed colonisation as compared to those dressed with TH-13 (T. longibranchiatum). The levels of seed coat colonisation by TH-11 and TH-13 was shown to be correlated with the carboxymethylcellulase activity, as measured in the seed coats retreived from germinating dressed bean seeds. The seed coat colonisation was also associated with an increased activities of endo-1,3--glucanase and endochitinase measured in seed extracts, and an inhibitory effect of seed extracts onPythium sporangia germination. Pretreatment of TH-13-dressed seeds with a commercial cellulase improved all parameters mentioned above, thus suggesting a role of cellulase activity in the colonisation process and the linked protective effect. The possible role of hydrolytic enzymes in the protective effects is discussed. 相似文献
84.
光敏核不育水稻选育与利用的几个问题讨论 总被引:4,自引:0,他引:4
对现有光敏核不育材料进行了分类,分为4种遗传类型;其中,温光弱感到光敏核不育系是最为理 想的遗传工具,并就其选育途径和选择“粳不籼恢”繁殖制种技术体系进行了论证. 相似文献
85.
本文研究香菇干制过程的计算机控制。在研制了系统硬件之后,根据实验结果,确定了控制对象的广义数学模型,用飞升曲线法求取模型中各参数。用计算机仿真技术对几种常用的算法进行比较,得出了采用大林算法的控制方案。 相似文献
86.
Aleš Lebeda Ida Blok 《European journal of plant pathology / European Foundation for Plant Pathology》1990,96(1):51-54
Results are given on the occurrence of sexual compatibility types of seven isolates ofBremia lactucae originating fromLactuca serriola (prickly lettuce). It is concluded that the isolates studied are heterothallic. Both compatibility types (B1 en B2) were determined, but type B2 was prevalent. Sexual recombination ofB. lactucae isolates originating from wild and cultivated lettuce may occur.Samenvatting Zeven isolaten vanBremia lactucae, afkomstig vanLactuca serriola in Tsjechoslowakije, zijn onderzocht op hun sexuele compatibiliteitstype door ze te combineren met Nederlandse fysio's vanB. lactucae, afkomstig van cultuursla (L. sativa), waarvan het compatibiliteitstype (B1 of B2) bekend is. Alle isolaten vanL. serriola bleken heterothallisch te zijn, waarbij type B2 meer werd aangetroffen dan type B1. Sexuele recombinatie vanBremia-isolaten van wildeLactuca-soorten en cultuursla blijkt goed mogelijk te zijn. 相似文献
87.
试验分别用温汤去雄杂交和两种化学去雄剂化学去雄诱导草地早熟禾雄性不育,结果表明,在两种化学去 雄剂作用下去雄效果比较理想,温汤去雄雄性不育率达100%。 相似文献
88.
高寒牧区牧鸡鸭治蝗效果试验 总被引:3,自引:1,他引:3
在青海湖北岸高寒牧区利用人工饲养的鸡鸭进行放牧防治草原蝗虫。结果表明,在60d的防治期内,牧鸡鸭平均灭治效果达91.4%,为人工利用天敌治虫技术在高寒牧区的应用提供了依据。 相似文献
89.
The loreyi leaf worm,Mythimna (Acantholeucania) loreyi Duponchel (Lepidoptera, Noctuidae), is a pest of gramineous crops and causes significant economic damage to maize. In field
surveys on maize to determine the parasitoid community and its impact on the pest in the eastern Mediterranean region of Turkey,
nine parasitoid species were found associated with immature stages ofM. loreyi: The hymenopteran (Braconidae and Ichneumonidae) parasitoidsCotesia (=Apanteles) ruficrus (Haliday),Chelonus oculator Panzer,Meteorus ictericus Nees,Hyposoter didymator (Thunberg),Sinophorus sp.; and the dipteran (Tachinidae) parasitoidsPseudogonia rufifrons Wiedeman,Exorista rossica Mesnil,Gonia picea (Robineau-Desvoidy) andLinnaemya vulpina (Fallen) — the last three recorded for the first time as parasitoids ofM. loreyi in Turkey.C. ruficrus was the dominant parasitoid species, being recovered from 38.5% of the larvae collected and was also the most prevalent species,
existing in 91.0% of the fields in whichM. loreyi was found. Total parasitism levels achieved by braconid species was 41.4%, by ichneumonid parasitoids 4.8%, and by tachinid
parasitoids 1.9%. In a separate field experiment, seasonal population fluctuations and natural efficiency ofC. ruficrus onM. loreyi were found to be 35.1% and 42.4%, respectively. Population levels ofC. ruficrus were closely related to fluctuations in the population ofM. loreyi, with parasitism ranging between 0 and 77.3% during the study.
http://www.phytoparasitica.org posting Aug. 28, 2005. 相似文献
90.
The establishment of predacious mites in commercial orchards may be accelerated by the transfer of pruned wood in winter and
summer from donor orchards to release orchards. Following winter pruning, 3-year-old and older wood is collected and transported
as soon as possible in bundles to a release orchard for distribution. If the release orchard is composed of dwarf trees, then
one or two bundles of 5 kg each are placed vertically at the base of the trunk of every tree in the block (0.5 to 1 ha); if
the trees are of standard size, then four or five bundles used. Following summer pruning, annual shoots and suckers are distributed
immediately in a release orchard composed of dwarf trees by placing 12–15 branches on the foliage of fruit-bearing branches;
if the release orchard is composed of standard trees, then 50 branches are used. The pruned wood should have 20–25 leaves
and not less than one predator per leaf. The release orchard should have a light infestation (two or three mites per leaf)
of pest tetranychids. These phytophagous mites would serve as food and help establish the predators. The release orchard grower
should develop a pest management program based on the same groups of pesticides used in the donor orchard.
http://www.phytoparasitica.org posting Aug. 31, 2005. 相似文献