The Feasibility Study On The Rust Disease Of Oxytropis Ochrocephala Bunge

It has conducted the preliminary research to the rust disease of Oxytropis ochrocephala Bunge From 2005 to 2006, the main findings as follows:1.Through appraise the pathogen of Uromyces punctatus and investigate transfer host, it indicates the invade pathogen of oxytropis ochrocephala is Uromyces lapponicus Lagerh., its aeciospores have edges and corners, circle or ellipse types, the superficial densely grow faint yellow or the near colorless wart shape tips, the diameter of tips are 16 ~ 25μm, teliospores have near ball, ellipse or oval types, bud bore grow in the spore's peak or the flank, the surface is brown or tan, The diameter is 20.5 ~ 26.0×18.5 ~ 21.0 microns, wall thickness is 1.5 ~2.0mm, near smooth or the minority with warts, the handle is short and colorless ,extremely easy to fall off.This uromyces punctatus don't have summer spore, belong Demicyclic forms, its life cycle is composed by the load spore, the spermatium, the aeciospores and the teliospores, but has not discovered its load spore stage. In the open country investigation and the room vaccinates experiment to discover don't find this bug have transfer host.2.The investigation discovered the Uromyces punctatus has get sickness at the initial period of turning green. From mid-June to late-June and mid-July to late-july are peak of disease arise. The sick oxytropis ochrocephala's distances of absolutely height and the branching number and healthy one's start enlarge from early July, Henceforth maintain this kind of tendency until the late growth season , when the sick oxytropis ochrocephala's head flower is poding ,the number of pod and the seed in the pod are less than heathy Uromyces punctatus. The sick oxytropis ochrocephala gradually have the diseased plant dry to die after the beginning of July, from mid-August have the big area sick oxytropis ochrocephala dry to die.3.The result of the test indicate that when the wattle of an oxytropis ochrocephala were infected by Uromyces punctatus over 40 percent, Its thousand grains' weight, germination power and the germination rate would be distinctly lower than the healthy one's(P<0.05).As the harm of Uromyces punctatus increases, It would also have influence on the height of the seedling, the fresh weight of 100 seedlings, the length of radicle. Infected by rust disease, both the chlorophyll content and water content in the leaf would decrease with different extent. Along with the aggravation of the disease, the decrease of chlorophyll content and water content goes up, and between the metaphase and anaphase of aeciospores, the decrease comes to its peak. Chlorophyll content and water content ascend at initial stages of winter spores no matter how hard the disease it experienced, but the potential of its instauration decreases as the degree of disease's harm increase.