① Pyrethroid pyrethrum is a famous insecticidal plant, which was introduced to Europe, America and Japan from West Asia as early as the middle of19th century. Yunnan and other places in China began to introduce and cultivate from abroad in the mid-1940s. The effective insecticidal components of this kind of plants are pyrethrins ⅰ, ⅱ (pyrethroid) and ⅱ); Botanical insecticides composed of six components, such as Ciner-INS Ⅱ, I] (Ciner-INS Ⅱ, II) and Jasmolini Ⅱ (Jasmolini, II), have been used for many years, but insects have almost no drug resistance, so the development of pyrethrum has become a hot spot in the development of natural insecticides.
(2) Azadirachta indica is a subtropical tree native to arid areas of Asia. It is cultivated in some countries in Central and South America. Extracts from different parts of the tree, especially its seeds, have shown the effects of inhibiting feeding, repelling, toxicity and endocrine interference to many insects of different ages. As a natural botanical insecticide, Indocalamus oil has been used in developing countries for many years. Azadirachtin, a triterpenoid, is the main insecticidal active ingredient in indoleamine oil. When the dosage of azadirachtin reached 0. 1m/L, it showed good activity and was harmless to people and animals. In view of its safety to environment, people and animals, the United States, India and some other countries are developing it. For example, Margosano produced in the United States has been registered as a commercial patent, and the product is made of seed extract, which has been approved by the environmental protection department for non-edible crops and nurseries; This improved preparation also has a market in the American market. India has produced "Azadirachta -mark", and Canada has begun to consider developing this pesticide. Myanmar extracted a large amount of Indosinian oil for export. High indoor temperature, dry climate and no typhoon are required, so many areas in Hainan and Yunnan are very suitable for planting. South China Agricultural University 1986 successfully introduced Hainan. And a small amount of culture was carried out. Yunnan, Sichuan and other provinces have also successfully introduced in dry-hot valleys and dry-hot areas.
③ Celastrus orbiculatus. It is a perennial woody vine of Celastraceae. Farmers in producing areas have long recognized that root bark has insecticidal activity and used root bark powder and leaf powder to control some vegetable pests, so it is called "vegetable insect medicine". I(CelangulinsI-IV is an effective insecticidal component isolated from Northwest Agricultural University in 1980s, and its chemical structure is identified as dihydroagarwood furan sesquiterpene. At the same time, the insecticidal efficacy tests of various formulations of Celastrus angulatus insecticidal preparation were carried out, the quality control methods and standards were established, the distribution of resource plants was investigated, and the introduction and cultivation experiments were carried out. ④ Stellera chamaejasme (Stellera chamaejasme). ) is a perennial herb of Stellera chamaejasme with high insecticidal activity. The insecticidal active components of Stellera chamaejasme were studied in Sichuan University. "A new class of active compounds with C6-C5-C6 structural skeleton was isolated from the root of Stellera chamaejasme for the first time. The structure-activity relationship study shows that the benzene ring or six-carbon ring structure at both ends of the main chain of the active compound is one of the core structures of the activity. With the increase of molecular skeleton unsaturation, the insecticidal activity also increases accordingly. Studies on insecticidal mechanism showed that these compounds had strong inhibitory effects on the activities of Ca2+-Mg2+-ATPase and AchE in insect cell membrane, and also had inhibitory effects on carboxylesterase and GSTase. Zhang Guozhou, etc. The ethanol extract of Stellera chamaejasme has strong biological activity against Pieris rapae larvae, Asian corncob larvae and Myzus persicae. Umbelline, Daphne, Stellera chamaejasme chromone and β -sitosterol are four active ingredients. ) has been separated and identified by activity tracking method.