It is known that closely related crossbreeding leads to a decrease in offspring due to homozygous lethal genes. In gladiolus due to its polyploidy decrease in vitality at single use of ingots has little effect, but at pollination of gladiolus flowers with pollen (pollen from another flower of the same plant) the number of capsules and ripe seeds decreases in comparison with these indicators at artificial intervarietal pollination. The death of plants obtained from seeds from closely related pollination is noted at the stage of seedlings and further development of young plants, so that flowering reaches barely half of all the shoots, their development occurs slowly, so that flowering occurs not earlier than the 4th year after sowing, while seedlings from crosses or free pollination bloom on the 2nd-3rd year. Since almost all gladiolus varieties are derived from crossing varieties with each other, the offspring of self-pollination are essentially a second-generation (F2) hybrid and show signs of initial varieties.
Thus, 86.6% of hybrids had a small flower in their offspring from self-pollination of the large pink variety, which occurred from the crossing of the Happy End and Spring Made varieties, typical for the paternal variety (Spring Made), and 13.4% - the average, as in the mother's variety - the color of the flower varied from white to light red (the original varieties had orange-red and yellow flowers). Self-pollination of the fine flower yellow Spring Made variety resulted in seedlings with predominance of yellow small flowers. In the offspring of gladiolus, recessive symptoms (large flower, white color) appear in the offspring; it is characterized by a greater uniformity of flower color, but at the same time, a large number of "malocultured" signs: a short rare inflorescence, incorrect arrangement of flowers, weak lobes, a long tube. Seedlings from self-pollination do not provide material for selection of promising forms, but can be used for repeated crosses to create heterosis powerful forms of cultural gladiolus. So far, this technique has been poorly used in the selection of gladiolus.
Pollination of fruit crops is noticeably different from pollination of field and vegetable crops. Fruit plants bloom in the early spring months, when wild insects and honeybees are still scarce. Cold weather hinders the flight of pollinator insects. Most fruit growers are well aware that honey bees are especially needed in the garden in cold weather. With normal flowering of adult trees on an apple orchard hectare there are about 2.5 million flowers, of which only 3-5% are fertilized and converted into realizable fruits.
Among fruit crops, apple and cherry varieties are the best examples of self-sterilization. In order for cross-pollination to be effective, there must be compatible varieties in the garden. If two or more apple-trees grow in the garden, but the fruit is not tied with cross-pollination, then the varieties are intersterile. Almost all varieties of pears are self-sterile, although they are characterized by greater fluctuations in the degree of sterility than apple trees and cherries. Plums of Japanese origin are the most self-sterile, while plums of European origin tend to be self-fertilizing. Cherry, peach, blackcurrant, raspberry and blackberry varieties are almost self-fertilizing, but they need insects to ensure self-fertilization.
Self-sterile varieties require insects that provide effective cross-pollination. Often the wrong point of view is that self-fertilizing plants pollinate without insects. Cross-pollination between two self-fertilizing varieties always provides a better yield. Self-fertilizing plant types require less work by insects to produce fruits than do self-sterile plants. However, it is essential that the insects are evenly distributed in the garden. Even if the pollinator varieties are well placed, cross-pollination depends on many interrelated and complex factors. Not all visits to flowers by insects are effective. For example, an insect that is well pollen-covered provides cross-pollination of only a few flowers, because the supply of complete pollen on the insect's body is quickly consumed.
For pollination in the garden in unfavorable weather need families consisting of about 2.3 kg of adult bees and at least 6 frames of breeding. If bees are purchased for pollination in the south, the weight of the package for settling one beehive should be at least 2.3 kg. Packaged bees should arrive at the site 3--5 days before flowering to form a family and settle in with the new area before the pollination. Bees should be provided with sufficient space to store feed and the uterus should be given enough space to lay eggs. A two-hull beehive is sufficient for families that have been through the winter. Package bees of the second beehive building with honeycombs are given about 10 days after transplanting them into a beehive, which would be.