Wild plant populations that cannot be controlled can be a factor in decreasing production of cultivated plants. Various types of wild plants or weeds are considered to be very detrimental to crystal guava farmers in Wates Village, Ngaliyan District, Semarang City. Not to mention the existence of pest attacks is a factor that can reduce yields of crystal guava. Excess control using chemicals such as herbicides and pesticides causes high costs for farmers. Concerns about the high selling price of crystal guava fruit which can reduce the number of enthusiasts are unavoidable.
Seeing the problems that occurred, the 2022/2023 Thematic KKN Team PPK Ormawa HMD Agricultural Science Undip carried out socialization and assistance on the use of weeds as biopesticides. This program adopts the concept of utilizing wild plants that are considered harmful and useless to become useful plants because they contain compounds that can control pests in crystal guava plants. The wild plant used is bandotan or Ageratum conyzoides which has flavonoids, saponins, coumarine, HCN, 5% eugenol, and essential oils which are able to repel pests and inhibit the development of pests, especially insect pests.
The program, which was implemented on December 29, 2022 at the Pendopo Agung Kebun Gapuro, Wates Village, Semarang, was accompanied by Agus Subhan Prasetyo, S.P., M.Si. as the supervisor of the Thematic KKN Team PPK Ormawa HMD Agricultural Science Undip and collaborated with the Agroecotechnology Study Program Undip led by Dr. Dian Safitri, S.P., M.Si. The target of this program is aimed at all farmer groups in Wates Village, including the Sumber Raharjo Farmer Group, the Rejo Tani Farmer Group, and the Rukun Makmur Women Farmer Group.
The activity was carried out by utilizing wild plants, namely bandotan, to become a natural pesticide that is able to control aphids that attack crystal guava plants. The implementation of the activity begins with the delivery of basic material. The material brought by the Thematic KKN Team PPK Ormawa HMD Agricultural Science Undip related to the dangers of using herbicides and the use of bandotan plant as a vegetable pesticide followed by direct practice of making biopesticides with farmers. The enthusiasm of the farmers was shown by the large number of participants who attended the demonstration and they were active in asking questions about the material that had been presented.
The demonstration of making biopesticide from bandotan plant begins with pulverizing ½ kg of bandotan leaves until smooth and removing the sap, then putting it in a container containing 1 liter of water and then soaking it for 24 hours. After soaking, the bandotan leaf extract is filtered into a container. Before being applied to the plant, bandotan leaf extract is mixed with 2 grams of detergent and then stirred until smooth. The bandotan leaf extract solution can be sprayed all over the plant with spraying times in the morning and evening to make it more effective.
All participants paid attention to the production steps of making biopesticides. It is hoped that the Wates Village farmers will be able to implement the activities that have been carried out by the Thematic KKN Team PPK Ormawa HMD Agricultural Science Undip as a form of pest and weed control by paying attention to ecological aspects so that good quality crystal guava plants are produced without reducing yields.