Management Technology of Grape flowering stage in Solar greenhouse

Management Technology of Grape flowering stage in Solar greenhouse

1 the core goal of flowering management

Comprehensive use of various technical measures to balance tree nutrition, reduce nutrient consumption, maintain dynamic balance between plant growth and flowering and fruit setting, and then make the distribution of tree nutrition more reasonable, and inflorescence get more nutrients, ensure better development and maturity of flower organs, lay a solid foundation for normal flowering, pollination and fertilization, and improve fruit setting rate.

(2) Management from inflorescence appearance to inflorescence expansion.

From mid-late January to early February, inflorescences grow from new shoots to the pre-anthesis stage in which inflorescences gradually elongate, stretch and buds develop and mature. The main technical points are as follows:

2.1 thinning branches. When you can directly see whether there are inflorescences on the new shoots, you can properly remove too many developing branches and retain the fruiting branches. Wipe off the sprouting of the root and the over-dense and weak branches on the fruiting branch group as soon as possible. In addition, multiple shoots growing on the same bud eye retain only the most robust or inflorescence shoots.

2.2 organize inflorescences. Through artificial selective trimming, reasonable regulation of tree load and increase of leaf-fruit ratio are beneficial to centralized supply of inflorescences left by tree nutrients, improve fruit setting rate, make ear compact, ear shape beautiful, and improve fruit quality.

2.2.1 thinning inflorescences. According to the tree potential and reasonable load 10 ~ 15 days before flowering, the inflorescences that were too dense and too weak were thinned, and one inflorescence was retained on the strong branch and the mediocre branch. In the case of low yield in the same year, strong branches can be considered to retain 2 inflorescences in order to achieve the purpose of increasing production. Remove two inflorescences from the same shoot that are not growing well.

2.2.2 pinch the tip of the inflorescence. Victoria grape is a large panicle variety 5 ~ 7 days before flowering, and its inflorescence length can reach 20 ~ 28 cm. In order to increase the fruit setting rate, the accessory spike can be cut off, and the whole length of 1 × 4 ~ 1 × 5 can be cut off from the top of the whole inflorescence and the top of the larger branch ear in the upper part of the ear. If the retained inflorescence branch spike is too dense, it is also necessary to properly cut off part of the thin branch spike with poor growth position. After this arrangement, the remaining inflorescences can get more nutrition during flowering and fruit setting, reduce the occurrence of falling flowers and fruits, and ensure the quality of fruit ears.

2.3 temperature and humidity management. The room temperature during the day is 20 ℃ ~ 27 ℃, the night time is 15 ℃ ~ 18 ℃, and the relative humidity is 60% ~ 65%. During this period, the temperature is greatly affected by the change of external temperature. When the weather is clear, the indoor temperature reaches 27 ℃ at noon, the air outlet can be opened and the air volume increases gradually with the increase of temperature. In the afternoon, the air outlet is closed at about 24 ℃, and the grass is covered at about 20 ℃ at room temperature. When the external temperature is too cold, two acts can be hung at the indoor front window, or the outer layer of the grass can be covered with plastic film to keep warm at night. The greenhouse temperature is required not to be too high during the day and low at night, otherwise it will lead to excessive growth or slow growth of fruiting branches, poor development of inflorescences and floral organs, slow growth of inflorescences and so on.

2.4 Water and fertilizer management. During the inflorescence emergence period, if the plant growth is weak, topdressing can be applied once, and magnetic nano-modified nitrogen fertilizer (N ≥ 46%) 15 ~ 20 kg/667 m ~ 2 and rooting bacteria fertilizer 5 ~ 10 kg/667 m ~ 2 are applied with water flushing. Pre-anthesis fertilizer can be applied once 7 ~ 10 days before flowering, 20 ~ 30 kg/667 / m ~ 2 of N, P, K (17-17-17) balanced compound fertilizer was applied on the pond surface, and water-soluble compound fertilizer (20-20-20 μ m ~ 2 TEL te) was applied with water flushing. It is worth noting that pre-flowering fertilizer can not be excessive application of nitrogen fertilizer, otherwise it is easy to cause new shoots to grow. 0.3% borax solution was sprayed on the leaves for 1 ~ 2 times. In addition, the fertilizer and water management at all stages before flowering should be strengthened to increase tree accumulation, which can effectively reduce the occurrence probability of Victoria parthenocarpy.

(3) flowering management

In mid-February, the first flower of indoor grapes bloomed to the stage of full bloom and fruit setting. The main technical points are as follows:

3.1 bind the tendrils to the new tips. When the new shoot grows to 30 ~ 50 cm, a single branch is tied to make it evenly distributed on the shelf surface. In order to make efficient use of space and reasonably increase the load, the new shoot is tied to the shelf surface along the trunk growth direction, and the weaker new shoot is allowed to grow upright in order to be strong. Strong branches can be slightly sprained at the base of 2 ~ 4 nodes to ease their growth potential. The strength of the new shoots should be small and the action should be light, otherwise it is very easy to make the new shoots fall off from the grape branches and cause unnecessary losses. The specific operation method is to bind the base of the new tip with one hand, lead the upper part of the new tip to the steel wire on the shelf surface with the other, and then bind and fix it. Remove tendrils while binding new shoots to save nutrition and prevent tree shape from being disturbed.

3.2 Heart extraction and secondary tip treatment. From 3 ~ 5 days before flowering to the first flowering stage, the heart of strong branches should be picked early and weak branches should be late. Generally, 5 ~ 7 leaves are reserved above the inflorescence, and 8 ~ 10 leaves are reserved for the vegetative branches without ear. The suitable coring degree is that the leaves in the coring part are equivalent to 1 ~ 1 ~ 2 of the normal leaves. The secondary shoots below the inflorescence were all removed, and only 1 ~ 2 secondary shoots at the top were retained above the inflorescence, leaving 2 ~ 3 leaves to pick the heart repeatedly each time.

3.3 temperature and humidity and water and fertilizer management. The room temperature is 25 ℃ ~ 27 ℃ during the day and 15 ℃ ~ 20 ℃ at night, and the relative humidity is about 60%. When the room temperature reaches 27 ℃, the temperature should be controlled at about 25 ℃. Higher than 30 ℃ during the day or less than 15 ℃ at night will adversely affect the various organs of the flower, thus affecting the normal progress of pollination and fertilization, resulting in a large number of flower and fruit drop. In addition, the flowering period is generally not watering and topdressing.

(4) Disease control

Spraying 70% sulvex suspension 1 000 ~ 1 500 times before and after anthesis or 50% Kaiser water dispersible granules 500 ~ 1 500 times each can effectively prevent the occurrence of grape gray mildew and downy mildew. Or at the initial stage of pathogen infection, the above agents were sprayed every 5 ~ 7 days for 2 ~ 3 times continuously. In order to prevent the occurrence of drug damage, it is not suitable to spray at noon on a sunny day.