The Effects Of Factors On Occurrence Of Locust And Development Of New Technologies For Management In Shandong

Locust plague is the serious problem in Shandong Province, the occurring area are large. Locust seriously occurs recently. In order to control locusts thousands tons of pesticides had been sprayed and the cost of control more than 1 million USD per year. It needs to study on the effects of key factors on occurrence of locust and development of new control technologies. In this paper the distribution, occurrence and control area for locust have been determinated through field investing and analysis of data. Especially, the key fators affecting on occurrence of locust have been researched based on field experiments and analysis of data. Some new techniques for management of locust have been researched and demonstrated in large scale. The new system for management of locust to integrate ecological control, biological control and chemical control has been developed in Shandong.The main results are as following:1. There is about 567500ha, and distributes in 31 countries in Shandong. There are four types of locust breeding regions, sea coastal locust breeding region, lake locust breeding region, river locust breeding region and flood locust breeding region. The locust occurring area had been increasing since the end of 20 century in Shandong. The mean densities of locust also were increasing. The proportion of control area in occurring area was also increasing.2. Results of experiments showed that densities of egg, distribution of egg, survival proportion of egg, rainfall, temperature and coverage of plant are key factors to influence on locust occurrence in Shandong. The surviving and density of locust egg are positive to occurrence of first generation of locust. Water is the key factor to influence on the environment of locust breeding region. Rainfall, quantity of water in Yellow River and level of lake water is negative to locust occurrence. Temperature in Januray, November, and December is important, mainly infuences on the over winter eggs surviving. The higher temperature in these months, the higher surviving and serious occurrence are. The coverage of plant affects on the locust breeding environments. The coverage of plant is higher than 70% where is not suitable for locusts lay eggs. In some certain conditions, the lower coverage of plant, the more suitable for locust laying eggs and the high densities of locust.3. It have been demonstrated that ecological control and biological control are environmental sound and sustainable ways for control locust plague, and have been selected as the fundamental methods in locust management program. Several biologica lcontrol agents, such as Nosema locustae and Metarhzium have been demonstrated in field Shandong and the results showed effective for control locust. But it is necessary to usechemical control when locust outbreak. Several new chemicals, such as Regent, Dasburn and so on have been selected and demonstrated in large scale in Shandong.