In recent years, the occurrence and harm of many kinds of pests and diseases have become increasingly serious in Yunnan sugarcane areas, which have greatly affected the sustained and stable development of sugarcane pr...In recent years, the occurrence and harm of many kinds of pests and diseases have become increasingly serious in Yunnan sugarcane areas, which have greatly affected the sustained and stable development of sugarcane production, so the situation of their prevention and control has become rigorous. In order to scien- tifically and effectively prevent and control pests and diseases of sugarcane to en- sure the safety of sugarcane production, on the basis of an investigation and re- search, according to the present situation of sugarcane production in Yunnan, the occurrence dynamics of major pests and diseases of sugarcane were analyzed, and corresponding control strategies were proposed according to the major pests and diseases as well as their occurrence and damage characteristics.展开更多
This study was aimed at determining the effects of mixed and single cropping agroecosystems on the prevalence of different species of insect pests and coccinellids. It involved six growing crops： maize Zea mays L., b...This study was aimed at determining the effects of mixed and single cropping agroecosystems on the prevalence of different species of insect pests and coccinellids. It involved six growing crops： maize Zea mays L., beans Phaseolus vulgaris L. and cowpeas Vignaunguiculata L. Walp in single and mixed stands and sampling throughout the phenology of the crops. Eight insect pest species were recorded on maize grown alone, while thirty seven insect species were endemic on cowpea mono cropped and were of six orders whereas twenty two insect pest species occurred on beans. The predator population was most abundant in the mixed stands of maize and beans （2.33 predators per 30 aphids） as compared to their occurrence in pure stands of cowpeas （0.85 predators per 30 aphids） as there were numerous aphids on beans at pre-flowering phase that supported a higher population level of coccinellids. Also, predator population was at the peak during the tussling stage of maize as they fed on the pollen grains while aphids on cowpeas co-existed mutualistically with black ants that protected them against predation. The genus Cheilomenes spp. was the most ubiquitous predator with a mean of 4.00 individuals per 30 aphids while Hippodamiavariegata was the least abundant predator species with a mean of 0.92 individuals per 30 aphids in all the agroecosystems as the Cheilomenes spp. had a faster discovery rate, range of perception, effective capture efficiency and a shorter handling time of a prey.展开更多
Schistosomiasis, an important parasitic disease, is severely harmful to human heath in China . The beach along the Yangtze River is a important habitat of snail that is Schistosomiasis＇s only intermediate host. pro...Schistosomiasis, an important parasitic disease, is severely harmful to human heath in China . The beach along the Yangtze River is a important habitat of snail that is Schistosomiasis＇s only intermediate host. program of afforesting for wiping out snail（Oncomelania hupensisi） and Schistosomiasis, comprehensive administration and exploitation of the three kinds of beaches proposed by Peng Zhenhna and Jiang Zehui is a pioneering.work hased on the ecological and economic theory. The development process of forestry for snail control and Schistosomiasis prevention is reviewed, and mechanisms and major afforesting techniques are summarized in this paper.展开更多
文摘In recent years, the occurrence and harm of many kinds of pests and diseases have become increasingly serious in Yunnan sugarcane areas, which have greatly affected the sustained and stable development of sugarcane production, so the situation of their prevention and control has become rigorous. In order to scien- tifically and effectively prevent and control pests and diseases of sugarcane to en- sure the safety of sugarcane production, on the basis of an investigation and re- search, according to the present situation of sugarcane production in Yunnan, the occurrence dynamics of major pests and diseases of sugarcane were analyzed, and corresponding control strategies were proposed according to the major pests and diseases as well as their occurrence and damage characteristics.
文摘This study was aimed at determining the effects of mixed and single cropping agroecosystems on the prevalence of different species of insect pests and coccinellids. It involved six growing crops： maize Zea mays L., beans Phaseolus vulgaris L. and cowpeas Vignaunguiculata L. Walp in single and mixed stands and sampling throughout the phenology of the crops. Eight insect pest species were recorded on maize grown alone, while thirty seven insect species were endemic on cowpea mono cropped and were of six orders whereas twenty two insect pest species occurred on beans. The predator population was most abundant in the mixed stands of maize and beans （2.33 predators per 30 aphids） as compared to their occurrence in pure stands of cowpeas （0.85 predators per 30 aphids） as there were numerous aphids on beans at pre-flowering phase that supported a higher population level of coccinellids. Also, predator population was at the peak during the tussling stage of maize as they fed on the pollen grains while aphids on cowpeas co-existed mutualistically with black ants that protected them against predation. The genus Cheilomenes spp. was the most ubiquitous predator with a mean of 4.00 individuals per 30 aphids while Hippodamiavariegata was the least abundant predator species with a mean of 0.92 individuals per 30 aphids in all the agroecosystems as the Cheilomenes spp. had a faster discovery rate, range of perception, effective capture efficiency and a shorter handling time of a prey.
文摘Schistosomiasis, an important parasitic disease, is severely harmful to human heath in China . The beach along the Yangtze River is a important habitat of snail that is Schistosomiasis＇s only intermediate host. program of afforesting for wiping out snail（Oncomelania hupensisi） and Schistosomiasis, comprehensive administration and exploitation of the three kinds of beaches proposed by Peng Zhenhna and Jiang Zehui is a pioneering.work hased on the ecological and economic theory. The development process of forestry for snail control and Schistosomiasis prevention is reviewed, and mechanisms and major afforesting techniques are summarized in this paper.
