Detailed Explanation of the Causes and Control Methods of Peanut White Grubs
Peanut is the most important cash crop in China. As the peanut planting area continues to increase, the yield rises year by year, but the damage from peanut white grubs is also becoming more and more serious. They gnaw on the peanuts during growth and harvest, causing the peanuts to have wormholes, which seriously affects yield and quality. So what causes white grubs? How should they be controlled? Let's take a look together.
I. Causes of White Grub Occurrence
1. There has been no obvious change in peanut cultivation. When plowing and harrowing, the soil is not worked deep, only shallow plowing is done, or even no-till is used, which simply cannot destroy the living environment of white grubs. As a result, white grubs become more serious year after year.
2. In rural areas, most farmers like to use farmyard manure such as chicken manure or pig manure for fertilization, but these fertilizers are applied directly without being fully decomposed. They carry a large amount of bacteria and insect eggs, which also causes white grubs to run rampant.
3. Many farmers apply pesticides improperly. The concentration used is too low or the spraying amount is insufficient, or the same pesticide is used for control over a long period, leading to pesticide resistance. Therefore, white grubs become more serious year after year.
II. White Grub Control Methods
1. Deep plowing and land preparation
After harvest and before the end of the year, deep plow and prepare the land once, with a required depth of more than 25 cm. At the same time, combine this with irrigation of freezing water, which can effectively kill overwintering insect eggs. When using farmyard manure, microbial agents must be added for full decomposition and fermentation, which can effectively prevent white grubs from breeding.
2. Treatment before sowing
Before sowing, seed dressing can be done with 0% chlorpyrifos 100 mL + 70% imidacloprid 15 g + 50% thiram 40 g. This can not only effectively control white grubs, but also has excellent control effects on other underground pests and diseases. Alternatively, before land preparation, broadcast 3% phoxim granules at 2 kg per mu, which can also effectively prevent damage from underground pests.
3. Control during the growing period
White grubs mainly occur during the pod growth period, so from flowering and pegging to the pod-setting stage, that is, in July-August, use 250 mL of % phoxim, mix with 30 kg of soil, and broadcast it around the peanut plants, which can effectively control them. Or use a 0% phoxim 800-fold solution, remove the sprayer nozzle, and carry out root drenching, or use 40% isofenphos-methyl 800-fold for root drenching. Be sure to do this during the flowering and pegging stage.
The above is an introduction to the causes and control methods of peanut white grubs. We hope it can help you. To learn more related knowledge, please stay tuned to us.