黄瓜感染枯萎病后病理组织学的研究

 用病毒RNA (TMV RNA),寄主mRNA (烟草mRNA)及植物核糖体,建立了离体核酸核糖体反应体系及分析监测方法。测定了TMV RNA,mRNA与核糖体结合的饱含量及竞争系数。将此体系用于筛选植物病毒病选择性治疗药剂,并用原生质体,整株植物进行生测,检测离体筛选结果,测定了分子结构不同的抗病毒药物的选择性常数,分析了离体试验,原生质体试验及整株试验中的药物筛选阈值。

HSTOPATHOLOGICAL STUDY ON CUCUMBER INFECTED BY FUSARIUM WILT

The process of fungous infection and cytological structure changes in seedling roots from suscepti- ble and resistant cucumber cultivar. inoculated with Fusarium oxysporum f. sp. cucumerinum were studied in this paper. Fusarium spores germinated as infecting hyphae which might penetrate the host epidermal cells , pass through the cortical cell. , and then enter into the xylem vessels. After infected by the pathogen , some occlusions such as wall-coatings , tyloses and brown-like materials were formed consequently in the vesseles. The various reactions of occlusion were earlier and more extensive in re- sistant cultivar than in susceptible one. Tylose. were formed by elonged parenchyma cells and secreted from pits. Nucleus could be observed in tyloses and a parenchyma cell could produce more than one ty- loses simultaneously . The function of these occasions was to prevent the pathogen growth.