Law of Occurrence and the Damage of Main Diseases and Pests in Ligusticum chuanxiong Hort Field

[Objective]The aim was to provide scientific basis for the prevention and treatment of the main diseases and pests. [Method]The systematic investigation was carried out in the process of seedling and field cultivation of Ligusticum chuanxiong. [Result]The main diseases were root rot,Powdery mildew and Spot blight,while the main pests were Epinotia leucantha Meyrick,Prodenia litura Fabr.,Scarabaeoidea,Tetranychus cinnabarinus Boisduval and Delia platura Meigen. [Conclusion]The law of occurrence of main diseases and pests were confirmed.

Identification and Control of Persimmon anthracnose

[ Objective] The study aimed to research the identification of Persimmon anthracnose and its controlling methods.[ Method ] The pathogen and characteristics, infection and occurrence law, damage symptoms of persimmon anthracnose were stated simply and the methods for con- trolling the disease were summed up. [ Result] The pathogen of Persimmon anthracnose was Gloeospor/um kaki Hod, belonging to Deuteromycotina. Germination and invasion of the conidia, sporulation and growth of mycelium all required high temperature, with the optimum temperature of 25 ℃ and the lethal temperature of 50 ℃ （10 min）. The occurrence strength of Persimmon anthracnose related with the factors including host, environment, culture circumstances, mainly doing harm to the fruits and branches. The occurrence of the disease could be controlled by such agricultur- al measures as cleaning the orchard, using the resistant varieties and planting the disease-free seedlings, adopting the balanced fertilization, improving the irrigation and drainage systems, conducting the dense planting and thin branches, building garden using the seedling that grafting on planted stock and raising the grafted parts of the stock. When the incidence was heavy, it needed to spray the fungicides or protective agent for the control of the Persimmon anthracnose. The fungicides should be mainly sprayed on the lesion of shoot, fruit surface and branches. [ Conclusion] The study provided the reference for the control of the Persimmon anthracnose.

Occurrence Regulation and Control Measure Comparison of Rice Sheath Blight

Rice sheath blight is widely distributed throughout the world, it can cause damage on many kinds of crops. Pathogen characteristics, infection cycle, occurrence law, damage law and different control methods of rice sheath blight in China are summarized, which will provide foundation for further worldwide research on the disease.

Occurrence and Control of Brown Patch in Energy Oil Plants Euphorbia lathyris L.

[ Objective] The purpose was to study the occurrence law and control effect of brown patch of E. lathyris. [ Method ] The pathogen of brown patch in E. lathyris was isolated and identified in Xingyi of Guizhou Province in 2008 -2009, and disease symptom observation and field fungicide efficacy test were conducted. [ Result ] The pathogen of brown patch in E. lathyris was fungus in Pseudoc ercospora sp., its suitable growth temperature was 20 -35 ℃, its occurrence peak was from June to September, and its field incidence were 30% -60%. Field efficacy test showed that 5 kinds of fungicides such as Thiophanate-methyl, Mancozeb, etc. had certain control effect on the disease, the relative control effect was 54. 3% -82.5%, in which mancozeb had better control effect, while Thiediazole copper had worse control effect. [Conclusion] The study would provide theoretical reference for further research on the cultivation of E. lathyris with hiah vield and aualitv and control of brown hatch.