Grape grain reason summary
Varieties on the genetic variety characteristics: such as giant peak is characteristic of ovule development completely, ovule abnormal rate is as high as 48%, so the young fruit of nutrients less competitive and fruit drop off.Red globe grape yield is higher, the grape expands coloring period leads to the off grain.
Nutrition supply: the grape tree potential, vegetative growth and reproductive growth not harmonious, thanks to compete for nutrients and aggravate.If the tree storage nutritional deficiencies, flowering before and after a large number of nutrient flow to the vigorous growth of new shoots or vice tip, such as not rationally control will cause a lot of the fallen petal fruit drop.The growth tree storage of nutritional deficiencies, causes the ovule dysplasia, lead to drop phenomenon.Hormone use undeserved, solution with uneven off grain of grapes;Nitrogen fertilizer too much out of grapes
Management: grape flower before nitrogen, water too much cause foliage mong long;Leave too close, poor ventilation, affect pollination, and so on, all can cause a lot of grapes out of fruit.Grapes) coloring period lack of microelement boron, zinc etc out of grapes.
Meteorological factors: flowering abnormal weather, such as drought, low temperature and rainy season, blooming or wind can cause bad fertilization and a lot of fruit.Too late rain, less light, the temperature changes of environment, will also lead off grain.When temperature is too high (32 ℃ ~ 42 ℃), during the fruit coloring, part fruit grain of light direct victims, date, burning disease, black drying shrinkage, lead to grain.
Physiological fruit drop: when the grape fruit grain length to 3 ~ 4 mm large, part of the fruit will fall off due to malnutrition to stop development, known as the physiological fruit drop of grape.
Plant diseases and insect pests of fruit: grapes in the rainy season, high temperature, high humidity's most prone to disease, downy mildew, anthracnose disease, powdery mildew, black blain will make fruit such as a large number of loss.In mature before and after high temperature drying, vulnerable to the dangers of starscream, and fruit drop.
Grape grain of prevention and cure
Choose the well-bred, scientific pruning
Select floral organ development is a sound disease-resistant grape varieties.Scientific thin flower thinning, reasonable with branches and have fruit, reasonable load, stable tree potential;Timely before flower heart picked vice tip and control;Spend about 1 week before choke ear, ear.
On the basis of, pay attention to fall fertilization
Putaohua before 3 ~ 5 days to flowering control irrigation, after spend more reasonable irrigation and fertilization, p, k, control of nitrogen fertilizer.
Grape autumn tree fertilizer is the guarantee the nutrient storage, keep the tree body, guarantee the spring flowers, fruit, important measures to reduce the fruit drop.Autumn basal dressing is not enough, must be carried out in the spring fertilizer, and add a small amount of nitrogen fertilizer.Grapes and 6 ~ 8 month after flowering in high temperature and rainy season, fertilizer should be given priority to with high potassium and low nitrogen fertilizer, to control the urea or high nitrogen fertilizers, prevent branches moderate growth.
Scientific use of regulator, trace element supplement in time
Regulator could inhibit the growth of grape nutrition, improve the nutritive condition of flowering.When using, should be in strict accordance with the doses used, combined with the climate condition, cannot excessive or a small amount.
In the grapes of borax spraying 0.5% ~ 1.0%, before and after flowering to improve its fruit rate.By means of spraying on the leaf fertilizer, timely supply, boron, zinc, copper and other trace elements, added tree storage of nutritional deficiencies, promote increasing fruit-bearing rate, reduce the grape fruit drop phenomenon.
Combined with the environmental changes, to do a good job of plant diseases and insect pests prevention
Like a lack of rain dry grapes.During the rainy season, high temperature, high humidity under the condition of disease, pest and disease easily happened caused fruit drop off.
Downy mildew: the early onset of medicament, optional dimethomorph or ene, acyl urea cream cyanide, spray, depending on the weather conditions, use 2 ~ 3 times in a row.
