What are the precautions for bumblebee pollination in winter?
In winter, temperatures are relatively low, and because greenhouses are enclosed, many growers often choose bumblebees to carry out pollination work in order to improve their crops. However, during the bumblebee pollination process, due to environmental and climate change issues, in order not to affect the normal use of bumblebees, we need to pay attention to several points. Let's take a look together.
1. Pay attention to the harm of smoke fumigants to bumblebees
In winter, because ventilation periods are short, humidity inside the greenhouse is relatively high, so pests such as whiteflies, aphids, and thrips are more common. Under low-temperature and weak-light conditions, many farmers choose smoke fumigants to control pests in order not to increase humidity. Smoke fumigants have the advantages of fast insecticidal effect, no blind spots, low cost, and labor saving, but bumblebees are also a type of insect and will more or less be affected by smoke fumigants. Therefore, friends who choose to use bumblebees for pollination in winter greenhouse cultivation should note that during the bumblebee pollination period, it is best not to use smoke fumigants.
2. Pay attention to the impact of double-layer film on bumblebees
After entering winter, many growers choose double-layer film as a measure to increase and maintain temperature, because winter light is weak and daylight hours are short. With double-layer film, after sunlight enters the greenhouse and is filtered through the double-layer film, the visible light available to bumblebees will weaken and decrease; and if cloudy weather occurs, the filtered visible light available to bumblebees will be even less. This will cause bumblebees not only to work poorly, but even not to leave the hive to work. Therefore, in order to avoid this situation, before installing the greenhouse film, choose greenhouse film with good light transmittance, and the inner film can be installed as a pull-type so that the inner film can be pulled open during the day to increase light.
3. Be cautious when choosing pesticides
During the bumblebee pollination period, the choice of pesticide spraying is also crucial. It is best to choose low-toxicity or biological pesticides to avoid pesticide residues. If pesticides with high toxicity, high residues, and high systemic activity are used, it is very easy to cause bumblebee death. When spraying pesticides, pay attention to weather changes. Pesticides decompose faster under light and high temperature conditions than on cloudy days, so pay attention to the weather for the few days after spraying pesticides. If there are many cloudy days, the spraying interval should be appropriately extended.
4. Pay attention to the placement and insulation of the hive
In winter greenhouses, hives are generally hung on the back wall of the greenhouse, 1—1.2 m above the ground, and a shade board is built above the hive to prevent direct sunlight from shining on the hive. In northern winters, nighttime temperatures are relatively low and humidity is high, so insulation and moisture-proof work should also be done well. A breathable thin cotton quilt can be added over the hive.
The above is an introduction to the precautions for using bumblebees for pollination in winter. We hope it can help you. If you want to learn more related knowledge, please follow us.