1.植物病理學有那些分支學科？請你就其中3個主要分支學科，闡述其研究熱點和研究進展。（40分）
2.目前我國植物病害防治工作中存在那些主要問題？請你闡述解決這些問題的方法。（40分）
3.請你將下列英文資料翻譯為中文。（20分）
Koch's Postulates
In order to substantiate that an organism, group of organisms, or combination of organisms and environmental factors are causal agents for a disease one must fulfill Koch's postulates. While this principle and concept are universally accepted by all pathobiologists (plant and animal),it is all too often over looked and there are diseases with putative causal agents that have never been demonstrated by Koch's Postulates. Years of research may have been spent on organisms never proven to cause particular diseases. Whenever one speaks about, or hears about, a disease,one should always seek to find out if Koch's Postulates were performed.In effect, Koch's Postulates are the scientific method applied to pathobiology. As such, without them Pathobiology becomes an art and not a science.
Pathogen must ALWAYS be associated with disease in all diseased plants. There are no exceptions allowed.
Pathogen must be isolated and established in PURE culture. This may be difficult with obligate parasites, but methodologies have been developed to fulfill this requirement even with obligate parasites.
Inoculation of a healthy plant of the same variety must reproduce EXACTLY the same symptom(s). Inoculation must be of a healthy plant of the same species and cultivar. This may be difficult if one isolates from a plant of unknown cultivar.
The symptoms must be reproduced essentially identical to the initial diseased plant, taking into account differences between the initial plants environment and the health inoculate plant.
Pathogen must be reisolated from inoculated plant and its identity confirmed as the same as the original isolate. The organism recovered must be the identical to the original isolate. There are no exceptions.