【作者】 白玉明；

【导师】 袁秀英；

【作者基本信息】 内蒙古农业大学 ， 森林保护学， 2007， 硕士

【摘要】 应用生态学方法研究了乌兰布和沙漠边缘花棒灌丛地土壤资源的分布格局及花棒克隆特性对沙漠环境的生态适应性。对严重影响花棒正常生长发育的锈病病原进行了鉴定并且对其重寄生菌的生物学特性进行了研究。研究结果如下:1、花棒灌丛地土壤水分,有机质、全氮、速效钾和速效氮等养分含量的分布具有空间异质性。灌丛地表层(0～5cm)土壤的中细粒子(0. 25～0.02mm )含量高,并且土壤水分、有机质、全氮、速效钾和速效氮含量相对优越,“沃岛”现象明显,而且,由灌丛内向外,含量逐渐降低。2、花棒具有独特的克隆生长构型:由枝条遇沙埋形成长间隔物的典型的游击型克隆生长构型和由根条形成的典型的密集型克隆生长构型。且固定沙丘的花棒分株种群比半固定沙丘具有较大的密度、较小的平均株距及相似的分株高度。3、花棒锈病病原为Uromyces onobrychidis (Desm.)Lév.,重寄生菌为Sphaerellopsis sp.,重寄生菌生长最适温度是20～25℃;在20℃下,PDA培养基上,10d即可形成分生孢子器,12d可见溢出淡黄白色孢子角;葡萄糖、甘露醇、淀粉、麦芽糖均为该菌适宜的碳源;相对湿度70%～98%孢子均能萌发,在水滴中萌发率最高;自然光下萌发最好;对氮源的利用,菌丝生长以硝酸钠,甘氨酸,蛋白胨,天冬酸为好;产孢以天冬酸,蛋白胨最好,甘氨酸和牛肉膏不产孢。更多还原

【Abstract】 Distributing patern of soil properties, including soil moisture and nutrients beneath the shrubs of Hedysarum scoparium and its ecological adaptability of clonal traits to sandy habitats in Wulanbuhe desert were studied using field experiments. We also identified the pathogeny and researched the biological characters of its hyperparasitism. The results are as following:1.The soil nutrients, such as organic mater, total N, available K and hydrolytic N, and the soil moisture under the shrubs of H. scoparium were heterogeneously distributed. It has shown an evident phenomenon, called "island of fertility" in the shrubs because there were high content of medium-fine soil parfcles(0.25～0.02mm) and relatively abundant soil moisture, organic mater, total N, available K and hydrolytic N on the soil surface under the shrubs, and furthermore, the content of soil moisture and nutrients gradually decreased from the center of the shrubs to its edge in this soil layer.2.Hedysarum scoparium has special patterns of clone growth:the guerrilla pattern,which is made up of long dropping branch was covered by sands;the phalanx patterns,which composed of roots.Comparing with the ramet population in the semi-fixed dunes,the ramet population in the fixed dunes exhibited higher ramet density and smaller average ramet spacing.They had similar ramet height3.The pathogeny of Hedysarum scoparium rust is Uromyces onobrychidis (Desm.)Lév. and the hyperparasite is Sphaerellopsis sp.. The optimum growth temperature for Sphaerellopsis sp.was 15~25℃. After 10 days of at a temperature of 20℃on PDA,conidia were formed,after 12 days,yellow white spore horn was also produced.There were 4 kinds of carbon sources including glu-cose,mannitol,starch and maltase were optimum.The relative humidity for spore germination were 70%~98%,but best in drops of water.The scatter light was better for the spore germination.Among nitrogen sources, sodium nitrate, glycine and peptone were better for mycelia growth .the spore formation was better on asparagines, peptone and, no spore was produced on glycine.更多还原