I did a lot of research during my further study.
During the period of 1948, Qi Zhaosheng did a lot of research work on the application of systemic pesticides during his further study in the Agricultural Research Institute of Jerome Mountain, England. At that time, the research of laboratories in various countries had just begun. First of all, he studied the toxicity of bhc to plants by bioassay, and analyzed the internal absorption accumulated in crops at different development stages. In addition, he also took "Hiladan" (namely, octamethyl phosphate) as the experimental material, and carried out systematic conduction toxicity tests on leaves and roots of various crops, and achieved preliminary results. At the same time, it inspired him that if crop seeds can be treated with water-soluble octamethyl phosphate, the seedlings may have the effect of poisoning aphids and mites, which not only opens up a new way for pest control, but also is convenient to use and saves manpower and material resources.
Acquisition of invention patent
1949 in the second half of the year, Qi Zhaosheng began to design experiments. He selected broad bean seeds with an average grain weight of about 1g as experimental materials, soaked them in an aqueous solution with the concentration of octamethyl phosphate, and then potted them in a greenhouse. A few days later, he treated them below the toxicity limit of plants to produce seedlings, and he inoculated the plants with bean aphids. It was on this day that Dr. Hou Fu, Qi Zhaosheng's tutor, listened to his research report and rushed to the greenhouse to watch the death of the inoculated bean aphid; And spoke highly of this is a major discovery in the application of systemic medication. At the same time, Qi Zhaosheng also confirmed that broad bean seeds absorbed more water than drugs. The results showed that there was a phenomenon of "selective absorption" in broad bean seeds. Soon, Qi Zhaosheng conducted a field experiment of soaking broad bean seeds with chemical agents, and achieved remarkable yield-increasing effects. So he applied for an invention patent for this research, and wrote a paper published in the British journal Nature 1950. In his paper, he elaborated the mechanism of treating seeds and controlling aphids and mites with internal absorption agents, which made crops have preventive protection against pests after drug treatment, and increased the mode of action of drugs on absorbing mouthparts pests from contact to stomach poisoning. In 1950s and 1960s, this research result was often cited by researchers from all over the world.
1950 after Qi Zhaosheng returned to China, the research on systemic insecticides was further expanded, and many important achievements were made in the prevention and control of wheat and cotton pests, which effectively promoted the development of agricultural production.
2. Study on chemical control of cotton pests.
Dealing with cotton spiders
195 1 Shortly after returning to China, Qi Zhaosheng accepted the research task of cotton red spider control assigned by the Ministry of Agriculture. He took an open-top truck from Xinxiang, Henan Province to Liaocheng, Gaotang County, Shandong Province, and then visited cotton areas such as Haocheng and Hengshui in Hebei Province to fully understand the distribution and occurrence of cotton red spider. He recorded three host plants of red spider * * *11,belonging to 32 families and genera, and put forward measures to completely eradicate the overwintering host of cotton red spider and winter ploughing and winter irrigation. In order to control pests more effectively, chemical control of cotton pests was studied. At that time, the pesticide industry and chemical control technology in China were relatively weak. Facing the actual situation in China, Qi Zhaosheng went to Gaiping, Shanhaiguan and other places in Liaoning Province to investigate and summarize the equipment, cooking technology, packaging, transportation and supply of lime-sulfur mixture left over from the puppet government period in Northeast China. Then teach it to cotton farmers, so that this technology can be popularized and applied in cotton areas, and the harm of cotton red spider can be effectively controlled.
Control cotton aphid
From 65438 to 0953, Qi Zhaosheng stayed in the cotton area of Handan, Hebei. According to the needs of production, he carried out research on cotton aphid control. Especially, outstanding achievements have been made in the research on the occurrence law and chemical control countermeasures of cotton aphid. Aiming at the problem of vegetable oil chemicals (such as cotton oil soap, etc.) ) At that time, it was widely used to control cotton aphids, and he formulated two standard specifications and effective dilution concentration. In addition, the preparation method of tobacco lime water aphid killer is also proposed. In the mid-1950s, China began to produce HCH-C on a large scale, and Qi Zhaosheng studied the toxicity and control technology of this pesticide. After the production and promotion, the control effect of cotton aphid was obviously improved.
In 1960s, organophosphorus pesticides came out one after another in China. The pesticide parathion developed for the first time in China was tested on Qi Zhaosheng, and it was quickly applied to control aphids in a large area. In view of the first use of highly toxic organophosphorus pesticides in China, he summed up a set of strict safety operation rules from practice and suggested using the minimum diluted liquid medicine with the effective component of 30ppm in production. These suggestions and measures not only ensure the safety of cotton farmers, but also improve the control effect of cotton aphids, which has played a positive role in promoting the application of highly toxic pesticides in China.
Double effects of cotton bollworm and cotton spider
At the end of 1970s, the development and application of pyrethroid insecticides developed rapidly all over the world. In order to keep up with this situation, Qi Zhaosheng visited France, Britain and Ivory Coast, and made a detailed understanding and analysis of the development, synthesis and application of these drugs. In addition to making suggestions to relevant domestic departments, experiments were carried out in Xinxiang, Henan Province to control cotton bollworm with permethrin, cypermethrin, pyrethroid and deltamethrin, which created conditions for the popularization and application of such chemicals in cotton areas nationwide in the early 1980s. In his research, he also found that the mixture of pyrethroid and chlordimeform not only has obvious synergistic effect on cotton bollworm, but also can treat cotton spider, which greatly reduces the control cost.
Control corn borer
In view of the problems existing in chemical control of cotton pests, Qi Zhaosheng actively advocated the study of integrated control measures of cotton pests. 1952 put forward a number of comprehensive application measures when studying the control of cotton red spider. In the early 1970s, he emphasized the coordinated use of various cotton pests and various prevention and control measures, and gradually carried out comprehensive management of cotton diseases, insects, weeds, rats and other pests. In production, he found that the corn borer in wheat-cotton intercropping field did serious harm to cotton seedlings, and the stem breaking rate was as high as 30%. The reason is that the harvested wheat stalks are put in cotton rows, which makes the corn borer transfer to cotton seedlings and bite off the tender stems, causing harm. To this end, he suggested that the wheat straw should be taken out of the field in time, so as not to give the corn borer a chance to climb out and do harm. This simple and easy prevention method is easily accepted by the masses.
Establish a demonstration area for ecological pest control.
During the Sixth Five-Year Plan period, Qi Zhaosheng presided over six national units to undertake the national key tasks, namely, to establish comprehensive management bases and large-scale demonstration areas in the Yellow River basin and the middle and lower reaches of the Yangtze River. Under his leadership, according to the main components of the cotton field ecosystem and their relationships, the cooperative team carried out comprehensive control research on major pests and diseases such as cotton wilt, verticillium wilt, cotton aphid, cotton bollworm, cotton spider and bedbug. Through several years' efforts, five main pest control indicators have been formulated and revised, reducing the number of drug use and control investment; Through reasonable crop layout and trapping plants, the ecological diversity of cotton fields is enriched, which is beneficial to the reproduction of natural enemies, and the control effect is improved by combining rational drug use. It has also made gratifying achievements in the basic research of cotton bollworm, the life table of cotton bollworm and the identification of cotton variety resistance. Based on these achievements, they formulated comprehensive prevention and control measures for major cotton pests and diseases according to the characteristics of different cotton ecological zones, which effectively controlled the pests and diseases in the demonstration areas and received remarkable economic, social and ecological benefits. 1988 This research achievement won the second prize of National Science and Technology Progress Award. In the same year, Qi Zhaosheng was awarded the second prize of the State Council for his outstanding achievements in the pilot project of agricultural development in the Huang-Huai-Hai Plain.
Vigorously develop powder spraying equipment
Qi Zhaosheng not only took the lead in researching and introducing advanced technologies for cotton pest control, but also greatly improved pesticide application equipment. In 1950s, during the popularization and application of HCH powder, there was a lack of powder spraying equipment in rural areas. He visited the cotton area, summed up the experience of cotton farmers in preventing and controlling pests and diseases, and created a simple pesticide application tool of "skin rat". During the period of 1957, he improved the single-tube sprayer to have a nozzle when promoting the control of cotton aphid by absorbing phosphorus internally in Xinxiang, Henan Province, and the efficacy was doubled. As early as 1956, he cooperated with the Civil Aviation Administration to carry out the experiment of spraying BHC powder on An -2 aircraft to control cotton aphids in Anyang, Henan Province, which is a precedent for using aircraft to control pests in northern cotton areas of China. During the period of 1958- 1960, Qi Zhaosheng cooperated with the Civil Aviation Administration to carry out a large-scale experiment of controlling cotton bollworm by aircraft in Xinxiang County, Henan Province, and achieved remarkable results in increasing production in a large area. Through two years of prevention and control practice, a large number of data and experience of aircraft pest control have been accumulated, which has contributed to the development of aircraft pest control in China.
3. Develop new domestic pesticides.
System monitoring
With the wide application of pesticides, cotton insects have developed resistance to various pesticides. On the one hand, Qi Zhaosheng systematically monitored the development of cotton insect resistance and put forward the idea of stopping or delaying the development of cotton insect resistance, on the other hand, it made suggestions on developing new domestic pesticides. 1963, cotton farmers all over the country reported that the efficacy of internal phosphorus absorption in treating aphids decreased. He and his assistant immediately went deep into the cotton area to investigate and confirmed that the resistance of cotton aphid was increased by 7- 15 times respectively. In order to solve this problem, after research, he proposed soaking or dressing seeds with phorate, supplemented by spraying overwintering hosts in the early stage to reduce the invasion of aphids, alternately using chemicals such as phorate, spraying leaves on the back to contact insects and other methods, and achieved good results.
During this period, Qi Zhaosheng also cooperated with the pesticide room of our unit to screen "biocides" and synthesized 100 kinds of phosphate, phosphite and thiophosphate compounds. Four or five "biocides" were screened out and mixed with internal phosphorus to improve the effect of killing aphids. At the same time, he also screened and applied new chemicals to control aphids. In more than 50 drug samples of 1 1 and1,it was found that the efficacy of "baomianfeng" was 3- 15 times higher than that of phosphorus absorbed internally, and the effect of controlling cotton spiders was also confirmed.
Multi-party cooperation
Qi Zhaosheng realized from practice that the development of new pesticides in China should be carried out by the cooperation of pesticide synthesis research units and production units, so as to get twice the result with half the effort. He and his assistant focus on biological monitoring and efficacy identification of new pesticides. In the late 1950s, in cooperation with the Institute of Elements of Nankai University, the field experiments and tests of dithiophosphate pesticides were carried out. In the early 1960s, he took Spodoptera litura as a test insect and actively cooperated with Shenyang Institute of Chemical Technology to detect dichlorvos pesticides. He believes that this insecticide is highly toxic, can be absorbed and conducted by plants, and is effective in controlling chewing mouthparts pests. At the same time, the antifeedant "antifeedant amine" and five homologues synthesized by the Department of Chemistry of Tianjin Normal University were tested in the field. The results showed that the larvae of Helicoverpa armigera felt abnormal mouthparts after feeding on "antifeedant amine", and then stopped feeding and died. Immortal pupae, even after emergence into adults, are mostly deformed. At that time, this research reached the international advanced level.
Constantly experiment
197 1 Qi Zhaosheng According to the literature, monocrotophos B, which came out in the late 1960s, is very effective in controlling cotton bollworm and aphid mites. He actively suggested to the Ministry of Chemical Industry that it should be developed as soon as possible. At the same time, in cooperation with the Institute of Elements of Nankai University, a series of indoor and field experiments were carried out on small samples and pilot drug samples, which provided pharmacodynamic data for the official production of Qingdao pesticide plant.
In the cooperation with other units, Qi Zhaosheng always treats every job with an extremely rigorous scientific attitude and a very responsible work spirit. In 1970s, phoxim was used to control cotton bollworm in cooperation with Taiyuan Chemical Plant and Tianjin pesticide plant. Many field experiments show that phoxim has different degrees of phytotoxicity to cotton. At the drug appraisal meeting, he insisted on writing this accidental phenomenon into the appraisal book for reference in popularization and application. He cooperated with Shanxi Institute of Light Chemical Industry and other units to identify the efficacy of methomyl and mixed methomyl, pointing out that the latter emulsion has occasional phytotoxicity and suggested that it be processed into powder. Myzucarb is an efficient insecticide against many kinds of aphids, which was fully affirmed abroad at that time. However, he made a control test on the small samples provided by the relevant domestic units. The results showed that the efficacy of the pesticide against cotton aphids was far less than that of peach aphids and wheat aphids, and pointed out that the pesticide had obvious selectivity among different aphid species.
In the early 1980s, Qi Zhaosheng actively supported the research and development of aldicarb in Tianjin pesticide industry based on experimental data. At the same time, with the development of pesticides, guide our hospital to design related farm tools.