Use of plant extracts (Ricinus communis) to control undesirable insects in the cultivation of caupi beans

Abstract

The objetive was to evaluate the action of the extracts from the castor bean plant, the shells of the seeds, the seeds and the leaves of the castor bean plant on the insects that are likely to cause damage in the caupi-bean plant. The experiment was carried out at the Federal Institute of Education, Science and Technology of Pará (IFPA- Campus Bragança) located in the municipality of Bragança, located in the northeast region of the state of Pará. The trials were conducted in the first half of 2023, namely: 1-Screening of castor bean by-products, seed hulls, seeds and castor bean leaves using ethanol as solvent; 2- Dose response curve extracting bioactive substances from seed, seed and leaf hulls with ethanol. Casualized blocks (CBD) with three repetitions and four treatments, divided into four blocks, each block had 50 plants with plant spacing of 20cm and 50 cm between rows with local breaded bean cultivar. Treatments were applied once/week after the infestation appeared, after filtering dilution was done for each case in a single spray. Testing of formulates with an interval of one week in each treatment were applied: witness, MSM, SM and FoM, all using ethanol at 92.8° INPM in the preparation of SE and applied in the dosage of 10%(m/v). Evaluation of treatments was performed 48 hours after spraying by counting live and dead insects. The effects of oil and leaf and shell extracts from the castor bean plant on mortality of aphids, caterpillars, bedbugs and cowpeas in beans were investigated using second order regression analyzes. The analyzes were carried out in the Past 4.14 program. As the concentration of oil extracted from castor bean seeds is increased, there is an increase in the mortality rate. The concentrations of aqueous extracts from the castor bean leaves, more efficiency in the results. Thus, the plant extracts tested are a viable alternative for the control of Aphis craccivora, Bemisia tabaci, Diabrotica speciosa, Spodoptera eridania and Nezara viridula, being affordable products for easy preparation and application.