Biological Pollination
Pollination is a very important technological component of agricultural production in the conditions of glass-covered ground. Nowadays the pollination of tomatoes in greenhouses is realized by means of mechanical devices (electric vibrators, percussion onto espaliers) or with the aid of bees. Both of the methods have a lot of negative features and a low effectiveness. The new world tendency comes gradually instead of the ineffective technologies of pollination, which used before. It presents the application of bumble-bees in pollination process. This technology can improve the effectiveness of pollination and provide the positive increase of economical indexes in cultivation of various crops.
The technology of industry bumble-bee breeding is widely developed by many companies in Netherlands, Belgium, Israel. The formation of this sphere of production is also actively developed in Russian Federation. The main species for industry production and further practical application is Bombus terrestris.
The bumble-bee is an active pollinator of many plant species. Besides, it is a very important and necessary component for the support of ecological balance in nature. Bumble-bee families are used for the pollination of vegetable and small-fruit crops in glasshouses (tomato, eggplant, pepper, cucumber, strawberry and others). Bumble-bee application in pollination can provide the increase of yield-capacity. The addition of yield can amount from 5 to 25%, sometimes to 40%. The quality of fruits is enhanced by means of nutrient concentration rise. Therefore the quantity of marketable and fully-featured production increases and the number of nonconforming fruits decreases. It is observed the improvement of yield storability. At last bumble-bee pollination lowers labor inputs and enhances the level of cost effectiveness.
Directions for use
In dependence on species of cultivated crops and hive modification 5–10 hives with bumble-bees are set per 1 ha of greenhouse area. At first 3 hives should be disposed. After a week when the number of flowers increases one more hive is usually set. Then 2 hives more are added. The period of hive application in a greenhouse amounts to 7–10 weeks at optimal conditions (the availability of pollen for gathering, a temperature of 20–24°C, a humidity of 40–70%). The level of the minimal (7 weeks) and the maximal (10 weeks) periods of using depend on food quantity and the strength of a family (i.e. the number of individuals). The strength of the family reaches the maximum number of workers to 4–5th week after the placement in the greenhouse. Then the number of workers decreases. The change of hives is gradually realized after 8 weeks. The wasted hives should be utilized.
It is necessary to pay a particular attention to the correct disposition of hives on greenhouse area. The height of hive disposition in the greenhouse under the level of the ground should be 1–1.5 m. The hives should be disposed in such a manner that they are not mechanically damaged. They also mustn't be exposed to direct sunlight (overheat) and the influence of water (rain, condensate). It is necessary to ensure defense against ants. In the process of hive placement a small slope (near 5°) is made backward (a bee-entrance is elevated) in order that food (syrup) could be used entirely by bumble-bees. After the disposition of the hives on permanent places it is necessary to give 2–3 hours for the calming of bumble-bees. Then the bee-entrances can be opened.
It is necessary to remember that the abrupt changes (fluctuations) of temperature and air humidity influence very much on the flight intensiveness and the working efficiency of bumble-bee families. At the cooling of hives lower than 5°C or their overheating higher than 34°C the bumble-bee doesn't fly. In hot days bumble-bees fly in an early morning and in the beginning of evening.
In the process of chemical treatments the bumble-bees are removed from the greenhouse for a day or more dependently on the kind of chemical. The collection of the bumble-bees is made by the following manner. At first the left bee-entrance is closed, and in 2–3 hours (the time which is necessary for the bumble-bee collection) it is closed the right one. Before the start of treatment all the bee-entrances must be closed! It is forbidden application with synthetic chemicals (particularly insecticides), which have a wide range of action and a long residual influence. After the return of the hives on permanent places it is taken care that the orientation of bee-entrances should be in previous position. It is not recommended to disturb the bumble-bee hives without need.
