Cause analysis and control methods of cucurbit melon in greenhouse

Cucurbita melons refer to the female flowers of zucchini. Within 3-4 days after opening, the front part of the young fruit of zucchini changes from green to yellow, becomes thin and soft, the fruit expands rarely or even does not expand, the surface loses luster, the tip shrinks, and finally rotts or falls off. At present, melons have become a "roadblock" in the cultivation of zucchini. The causes and preventive measures of melons in zucchini are introduced to vegetable farmers.

Zucchini melons

I. Causes of melons

Zucchini melons are mainly caused by inappropriate environmental conditions or imbalance in nutrient supply.

1. Temperature. The temperature is too high, more than 35℃ during the day, higher than 20℃ at night, resulting in reduced photosynthesis of zucchini, enhanced respiration, a large number of carbohydrates transported to the stems and leaves, excessive growth of vines, malnutrition and melons. The temperature is too low, lower than 20℃ during the day and 10℃ at night, the absorption capacity of the roots of zucchini is weakened, and the photosynthesis is also reduced. Finally, due to nutritional hunger, melons appear.

2. Light. When the summer squash enters the flowering stage, if it encounters continuous cloudy days or continuous rainy days, the temperature difference between day and night is small, the photosynthesis of the summer squash will be affected, the production of nutrients is less than the consumption, and finally the melon will be transformed due to malnutrition.

3. Planting density. Density is also one of the factors affecting the melon transformation of summer squash. With high density, the roots of summer squash compete for nutrients in the soil, while the stems and leaves of the aboveground compete for space to extend. When the leaf area index is higher than 4, the light permeability decreases, the photosynthetic efficiency is not high, the consumption increases, and the melon transformation rate increases.

4. pollination. Due to poor pollination or no pollination of zucchini, the auxin of the plant cannot be produced in the ovary, resulting in the normal growth of the embryo and endosperm of zucchini. When the nutrient supply of female flowers is insufficient, the auxin content of the ovary will also decrease, and the fruit will not be produced.

II. Preventive measures

1. Adjust the temperature. Keep it at 25-30℃ during the day. If it exceeds 30℃, it should be released properly. Keep it at 15-20℃ at night. If the temperature is too low, it can be warmed by stove.

2. Supplemental lighting. Want to pull early late put straw mat to maintain the temperature inside shed, if encounter successive cloudy day or when the weather of continuous overcast rain, usable stick hang reflective film, the method that illuminate lamp strengthens illumination.

3. Determine the appropriate density. The planting density should be controlled at 2000-2500 plants per mu. When planting zucchini with large and small row spacing, the large row spacing is 80 cm, the small row spacing is 60 cm, and the plant spacing is 40 cm.

4. Hormone treatment. 2-3 days after the flowering of the female flowers of zucchini, spraying with 100 mg/kg gibberellin or 100 mg/kg of anti-falling element can make zucchini grow faster and not easy to meltdown.