Comprehensive Control of Strawberry Gray Mold in Greenhouse
Strawberry gray mold has become an important disease in strawberry in the greenhouse. Especially if the flowers and fruits are infected, it will quickly rot and spread rapidly, which will have a great impact on the yield. The weight may be reduced by more than 40%. Freeze Dried Food,Freeze Drying Sea Shrimp,Food Hyaluronic Acid Powder,Freeze Dried Carrot Powder Ningbo Nutrition Food Technology Co.,ltd. , https://www.collagenworkshop.com
(I) Symptoms: When the flower is infected, the flower buds appear as small spots with water-stained needles at the beginning, and then expand into a nearly round or irregular shaped lesion. The calyx gradually extends to the ovary and young fruit. Causes the young fruit to rot softly, and when the humidity in the shed is high, the diseased part produces brown-brown mildew. Fruit infestation mainly occurs on green fruits. The top stigma of the fruit is spotted with water spots, and then it turns into a gray-brown spot. At the same time, the pathogens infiltrate deep into the pulp. When the air is wet, the disease is wet and soft, and when the weather is dry, the disease is presented. Dry rot, eventually causing the fruit to fall. The leaf blade suffers damage, usually at the base of the leaf near the petiole, and begins to appear as a water-stained small spot. Afterwards, it expands into a nearly oval, semi-circular, or irregularly shaped gray-brown lesion, and eventually spreads to the petiole. In the end, the affected area was wet and rotted, the leaves were dead, and the diseased part was born with brown-brown mildew.
(B) the conditions of the disease: The most suitable temperature for the development of the bacteria is 18-23 °C. More than 80% of relative humidity in the air is favorable for onset. If the cold wave is frequent, overcast and rainy weather, the relative humidity of the air in the greenhouse is above 90%, field water accumulation, overcrowding, improper ventilation, etc. will aggravate the occurrence and spread of the disease.
(III) Comprehensive prevention and control technologies: 1. Agricultural control: Strengthen the cultivation and management, enhance the disease resistance of strawberries, control the occurrence of gray mold, and limit the spread of diseases. The main measures are as follows.
(1) Selection of disease-resistant varieties: selection of high-quality, high-yield, and disease-resistant varieties. All-stars and new stars have a better overall performance and are suitable for promotion. Its outstanding features are resistance to disease, compact plants, ventilation and light transmission, high firmness, bright color, and high yield and quality.
(2) Balanced fertilization: According to the amount of nitrogen, phosphorus, and potassium required for the growth and development of strawberries, the fertilizer is supplied in proportion to avoid excessive nitrogen fertilizer application. On the basis of applying base fertilizer, 20 kg of diammonium phosphate can be topdressed per acre during the period of rapid growth of plants, and 30 kg of compound fertilizer containing nitrogen, phosphorus, and potassium can be applied per acre during the fruiting period. Generally not only nitrogen fertilizer.
(3) High-Ridge Cultivation: Change the cultivation habits of the flat mulberry planting. Before planting, the land shall be formed into a ridge with a height of 10 centimeters and a width of 35 centimeters or a groove width of 30 centimeters, with each row on both sides of each ridge. The high ridge cultivation changed the original flood plain flood irrigation into a small ditch along the ditch, reduce the amount of water, reduce soil moisture, increase ground temperature, reduce water evaporation, reduce the humidity within the greenhouse.
(4) Directional cultivation: Strawberry has a certain regularity in the result area, that is, the side facing the arch. When planting, the seedlings bow back toward the side of the wide line, so that the ear is placed under the conditions of ridge ventilation and light transmission to enhance disease resistance, and it is also conducive to field management.