High-yielding cultivation techniques of Jufeng grape

Jufeng grape variety belongs to European and American hybrids. In the autumn of 1954, four branches were given by the delegation of Okayama University in Japan, which was propagated by Beijing Agricultural University and spread to the whole country in the 1960s. At present, among the fresh grape varieties sold in the market, Jufeng grape has large ears, large grains, bright color, thick meat, moderate sour and sweet, and is favored by consumers. Several key technical links should be paid attention to in cultivation management.

Main characters of Jufeng grape

1. Sprouting in the first and middle of March and flowering in early May. The accumulated temperature is 3132 ℃-3412 ℃ from germination to maturity.

2. Flower bud differentiation is good and yield is stable.

3. Leaves: medium-sized leaves, the general leaf area is 138.9 square centimeters, and the maximum leaf area under the core is 230square centimeters.

4. Resistance, susceptibility to black pox, gray mold, ear axis brown blight, downy mildew.

Poor performance of fruit setting and its causes

There are two kinds of bad fruit setting, one is low fruit setting rate, the other is serious fruit drop, and the other is good fruit setting, but the size and size of the ear is serious, the proportion of normal large seedless fruit is small, and the abnormal seedless small fruit is very large.

The main reasons for the bad fruit setting of Jufeng grape are:

1. The floral organ is abnormal. The abnormal rate of ovules in female organs is high, reaching 76.8%, and only 23.5% of the ovules can be pollinated normally.

2. The time of fertilization is long. It takes about 120 hours to complete the whole pollination, such as malnutrition or adverse environmental effects, leading to fruit drop due to abortion in the middle of fertilization.

3. Hormone imbalance in the body. The buds with poor fruit setting have higher contents of 920 and cytohormones, which can accelerate the development and maturation of ovules, but the germination of pollen tube is still relatively slow. as a result, the maturation process of male and female organs is not consistent, and most of the ovules miss the opportunity of fertilization. resulting in falling flowers and fruits.

4. The tree is out of balance and exuberant. The overgrowth of new shoots not only increases the content of hormones such as 920 in floral organ, but also competes for nutrients from stamens, weakens reproductive growth, causes failure of fertilized immature embryos, and increases the shedding of ovary and seedless fruit.

5. Environmental factors. When the daytime temperature was lower than 20 ℃ during flowering, the percentage of drupe increased, and rainfall washed away the secretion of stigma and made the pollen fall off.

Key cultivation techniques

Goal: to increase fruit setting rate, reduce fruit drop and stabilize yield

1. Control nitrogen fertilizer and tree potential before flowering. Before flowering, the new shoot is controlled below 70 cm, which is beneficial to fruit setting. The length of new shoot is more than 80 cm before flowering, and the fruit setting is low. The main measures to control the growth of new shoots are to control nitrogen fertilizer and water before flowering. In vineyards with medium fertility, base fertilizer can be applied less, 0.5 tons of chicken manure and 100 jin phosphate fertilizer can be applied per mu, without pre-bud fertilizer, 100 jin of compound fertilizer + 40 jin of potassium sulfate can be applied per mu after fruit sitting, which can be applied twice at an interval of 10 days. Apply 40 jin of potassium sulfate per mu in the hard core period, such as 20 jin of compound fertilizer per mu of vineyards with many hanging fruits. Coloring fertilizer and then apply appropriate potash fertilizer.

2. Pick the heart before flowering. From 5 days before flowering to the flowering stage, the weak shoots can leave 5 murine 6 leaves on the inflorescence, and the vigorous growth can leave 3 murine 5 leaves on the inflorescence, and enter the flowering and fruiting stage after 5 days. A large amount of nutrition is concentrated on the inflorescence, which is beneficial to fruit setting.

3. Spraying Zhuangzhuangsu on the leaves before flowering

The mequonium water agent (zhuangsu) produced by Jiangsu Nantong Shizhuang Chemical Co., Ltd. has an active ingredient of 25%, 15 mg per bottle and 15 jin of water per bottle. The concentration of growth can be increased by 12 jin of water per bottle and sprayed 5 times before flowering.

4. Yield control cultivation

High-quality fruit enters the supermarket, with a yield of 2500 jin per mu and 3400 clusters per mu. It is generally required that the yield per mu should be controlled at about 3500 jin, the ratio of vine to fruit should be 1: 0.8 / ml, the effective leaf surface should be 20 / 25 per bunch of fruit, the 5 leaves above the ear should not retain the leaf surface of the accessory tip, and the fifth leaf of the ear should be retained. There are 40 fruits per panicle. At present, the output of many vineyards is more than 4000 jin. The concept of high yield and low price sales should be gradually changed.