Herbal pesticides refer to the active ingredients extracted from herbs which are used for pest and disease control in crops or pure substances isolated from them. They are of great significance for the production of p...Herbal pesticides refer to the active ingredients extracted from herbs which are used for pest and disease control in crops or pure substances isolated from them. They are of great significance for the production of pollution-free agricultural products, as well as for exploiting the abundant plant resources in China for the prevention and control of pests. In this paper, the advantages of herbal pesticides,such as being environment-friendly, diverse patterns of action, safety for higher animals and the natural enemies of pests and making it hard for pests to produce resistance were first stated; then, Chinese herbal medicine resources with antibacterial and insecticidal activities from 49 families and their functions were reviewed, and 19kinds of herbal pesticides that have been developed and applied in China and seven kinds that have been produced on a large scale were also introduced; finally,three issues deserving further exploration during the development and application of herbal pesticides were presented, that is, research in variety selection and cultivation of herbs, and methods for extraction of active ingredients; basic research in the structure identification of herbal active ingredients, and the relationship between plant variety and active ingredients; development of lead compounds based on herbal active ingredients.展开更多
Aviation spraying is one of the most important methods for the treatment of forestry pests and diseases,which has a high operation efficiency and effectiveness.The combination of aviation spray and biological pesticid...Aviation spraying is one of the most important methods for the treatment of forestry pests and diseases,which has a high operation efficiency and effectiveness.The combination of aviation spray and biological pesticides to reduce the impact of pesticide spray on environment has become an important development in the direction of agricultural aviation.In order to explore the effects of aviation spray parameters on particle size distribution and activity retention of biological pesticide droplets,a system of droplets size test and an activity retention rate test system of biological pesticides were constructed.The related experiments were conducted by changing the structural parameters of the rotary cage nozzle(the diameter of nozzle)and the technical parameters of the operation(rotary speed and flow rate).The results showed that the average relative width S of the droplets of the rotary cage nozzle was close to 1,and the droplet distribution was uniform.The influence factors on the particle size distribution of biological pesticide droplets were rotary speed,nozzle diameter,medium and flow rate in descending order.The rotary speed,nozzle diameter,and medium had a significant influence on droplet size distribution.The average activity retention rate of Bacillus thuringiensis was 88.83%,and the germination rate of Beauveria bassiana was 89.80%.The rotary speed had a significant effect on the activity retention rate of bacterial and fungal biological pesticides,and it was negatively correlated.The rotary speed was between 3000-5000 r/min,and the activity retention rate was higher.The research results can provide guidance for spraying biological pesticides in aerial plant protection operations with rotary cage nozzle.展开更多
Paulownia is a fast-growing tree species that is mainly found in the central part of China. Three main cultivation areas of Paulownia are the Yellow-Huai-Hai Plain, south of the Yangtze River, and arid and semi-arid a...Paulownia is a fast-growing tree species that is mainly found in the central part of China. Three main cultivation areas of Paulownia are the Yellow-Huai-Hai Plain, south of the Yangtze River, and arid and semi-arid areas of Northwestern China. There are 9 species, 4 varieties and 4 forms used in the production in China. Study achievements were obtained in the fields of species/variety introduction, selection and breeding, afforestation techniques as well as the control of diseases and pests. The main problems existing in the current production include lack of improved varieties, mix-up of different varieties and variety degeneration due to the long course of a sexual reproduction. The author put forward countermeasures for the problems.展开更多
基金Supported by the International S&T Cooperation Program of China(2010DFA32810)~~
文摘Herbal pesticides refer to the active ingredients extracted from herbs which are used for pest and disease control in crops or pure substances isolated from them. They are of great significance for the production of pollution-free agricultural products, as well as for exploiting the abundant plant resources in China for the prevention and control of pests. In this paper, the advantages of herbal pesticides,such as being environment-friendly, diverse patterns of action, safety for higher animals and the natural enemies of pests and making it hard for pests to produce resistance were first stated; then, Chinese herbal medicine resources with antibacterial and insecticidal activities from 49 families and their functions were reviewed, and 19kinds of herbal pesticides that have been developed and applied in China and seven kinds that have been produced on a large scale were also introduced; finally,three issues deserving further exploration during the development and application of herbal pesticides were presented, that is, research in variety selection and cultivation of herbs, and methods for extraction of active ingredients; basic research in the structure identification of herbal active ingredients, and the relationship between plant variety and active ingredients; development of lead compounds based on herbal active ingredients.
基金The research was funded by the National Key Research and Development Program of the 13th Five-Year Plan(Project No.2018YFC1200400,and Project No.2018YFD0600202).
文摘Aviation spraying is one of the most important methods for the treatment of forestry pests and diseases,which has a high operation efficiency and effectiveness.The combination of aviation spray and biological pesticides to reduce the impact of pesticide spray on environment has become an important development in the direction of agricultural aviation.In order to explore the effects of aviation spray parameters on particle size distribution and activity retention of biological pesticide droplets,a system of droplets size test and an activity retention rate test system of biological pesticides were constructed.The related experiments were conducted by changing the structural parameters of the rotary cage nozzle(the diameter of nozzle)and the technical parameters of the operation(rotary speed and flow rate).The results showed that the average relative width S of the droplets of the rotary cage nozzle was close to 1,and the droplet distribution was uniform.The influence factors on the particle size distribution of biological pesticide droplets were rotary speed,nozzle diameter,medium and flow rate in descending order.The rotary speed,nozzle diameter,and medium had a significant influence on droplet size distribution.The average activity retention rate of Bacillus thuringiensis was 88.83%,and the germination rate of Beauveria bassiana was 89.80%.The rotary speed had a significant effect on the activity retention rate of bacterial and fungal biological pesticides,and it was negatively correlated.The rotary speed was between 3000-5000 r/min,and the activity retention rate was higher.The research results can provide guidance for spraying biological pesticides in aerial plant protection operations with rotary cage nozzle.
文摘Paulownia is a fast-growing tree species that is mainly found in the central part of China. Three main cultivation areas of Paulownia are the Yellow-Huai-Hai Plain, south of the Yangtze River, and arid and semi-arid areas of Northwestern China. There are 9 species, 4 varieties and 4 forms used in the production in China. Study achievements were obtained in the fields of species/variety introduction, selection and breeding, afforestation techniques as well as the control of diseases and pests. The main problems existing in the current production include lack of improved varieties, mix-up of different varieties and variety degeneration due to the long course of a sexual reproduction. The author put forward countermeasures for the problems.
