I. Reasons for early walnut-eating fruit
The main reason for the low and unstable production of the existing walnuts is the severity of the falling fruit, which, according to studies such as the wanggen constitution, is generally between 40 and 90 per cent. There were three peaks for the general flowering fruit, the first from the end of april to the middle of may, which accounted for 50 to 70 per cent of the total flowering fruit; the second for four to six weeks, from late may to late june, which accounted for 30 to 40 per cent; and the third for mid-june to mid-july, which accounted for 10 to 20 per cent。
1. Poor pollination
In the northern region, the temperature has changed sharply in the spring and has fallen sharply to below 0°c in the event of cold currents, sometimes accompanied by wind or rain, and the freezing of walnuts has lost their capacity to pollinate; even if the flowerers are not harmed and there is a lack of pollinators in bad weather conditions, they will fall to the ground as a result of poor pollination. Walnuts belong to females and males, and most of the time the same tree was open to females and males. According to tests by the hebei university of agriculture, the main plant varieties should be within 300 metres of pollination trees and be fertilized or not capable of pollination at more than 300 metres. There are currently walnut gardens that are not equipped with pollinating trees; young walnuts are flowered only by females, and without artificially assisted pollination, they will also fall in large numbers。
Some of the walnuts are planted in thin-soiled mountainous areas, with extensive post-plant management, insufficient fatty water, inappropriate trims, more dangerous pests, and inadequate nutrient accumulation of the trees, resulting in a large amount of physical fallout。
3. Disaster weather
Winds, storms, hails, etc. Can also lead to a great deal of fallout。
Ii. Measures to prevent falling fruit
1. Artificially assisted pollination
According to the experiment, artificial pollination of females at the beginning of the flower season can increase the rate of sitting fruit by 17. 3% - 19. 1%, and twice, by 26%。
(1) pollow harvesting and dilution. Collecting male sequences of near-dumping or fresh-dumping powder from staggered adult trees, spread them on paper and in dry areas, room temperature is maintained at 20-25°c, powder is distributed over a period of one to two days, pollen is sifted, bottled and placed at 2-5°c low temperatures. Bottled pollen storage should be air-friendly and too closed to reduce pollination. In order to facilitate pollination, one piece of raw powder may be diluted by mixing with 10 pieces of starch。
(2) pollination is scheduled. The female column is the best time for pollination when it is fractured and brightly coloured, and its inner plume is gleaned with a large amount of slime. The period is very short, with only two to three days, and the male pre-form species are often fertilized without a complete reversal of the pillars. These characteristics need to be understood in pollination。
(3) pollination methods. Artificial shivering can be performed using double-stammer bags containing 1:10 diluted pollen. They can also be sprayed with pollen 1:5,000 water suspension。
2. Spray micro-fertilizers, hormones
A flower spray of boron acid, rare earth and cactin can significantly increase the seating rate of walnut trees. According to a multifactor synthesis study conducted by the shanxi institute of forestry science in 1991-1992, the optimal concentrations for female flowering were 54 mg/kg and 475 mg/kg, respectively. Three factors affect the sibling rate in order of magnitude: cactin。
The three factors used at the same time were 61. 93 per cent seating, compared with 39. 7 per cent and an increase of 55 per cent. In addition, 0. 5 per cent urea and 0. 3 per cent potassium dihydrophosphate were sprayed during the flower season, which improved the nutrient status of the tree and promoted sit-ins。
3. Elimination of males
Absorption of male buds can save water and nutrients for female development, thereby improving the nutritional conditions of female development, increasing the sit-in rate and increasing yields. According to the analysis centre of the chinese institute of forestry science, a male budding volume of 0. 036 grams was increased to 0. 66 grams, increasing by 0. 624 grams, including 4. 3 per cent nitrogen, 1. 0 per cent phosphorus, 3. 2 per cent potassium, 11. 1 per cent protein and amino acid, 4. 3 per cent fat, 31. 4 per cent sugar and 11. 3 per cent gray. If a walnut is detached from 90 per cent of the male sequence, about 50 kg of moisture and 1. 1 to 1. 2 kg of dry matter can be saved. In a sense, the removal of male buds is a reverse water injection and fertilization measure. In principle, the period during which the male buds are removed is appropriate for early contracting, usually within 20 days before the buds begin to grow, i. E., when the buds expand。
The number of males is appropriate for 90-95 per cent of all-tree males. It is reported in the literature that there are 100 to 130 small flowers, 12 to 26 small flowers, 2 pharmacists and 900 pollen per room, which calculates that there are 1. 8 million pollen grains per male line. Although pollen sprouts range from 5 to 8 per cent, the remaining male sequences are sufficient. Cultivated and less lumbered plants may be shunned appropriately。
For seedlings, pollinators are properly small in size and the main planter can be quite diverse. Specific locomotive methods: a wooden pole with a length of 1 to 1. 5 metres, a branch to be pulled down, artificially disassembled or combined with a trim. The effect of hysteria on the production of walnut trees is clear, with an increase of 15 to 20 per cent in the rate of sit-in and 12. 8 to 37. 5 per cent in production。
