1. Temperature is not suitable

Melon vegetables suffer from high temperature and cold injury during their growing period, especially low ground temperature, which causes root dysplasia and reduces their absorption ability, resulting in insufficient nutritional supply of melon strips and melon melon.

Temperature is very important for greenhouse cultivation. When the daytime temperature in greenhouse is higher than 32 C and the night temperature is lower than 18 C, photosynergy will be hindered, assimilation products will increase, respiratory consumption will increase, and nutrient accumulation will decrease, which will lead to malnutrition and melon melon melon melon melon.

2. Carbon dioxide concentration

It's easy to melon when the concentration is too low.

3. Over-dense cultivation and unreasonable supply of fertilizer and water

Over-dense cultivation, lack of light, poor ventilation, resulting in canopy closure, unreasonable shelf shape, is not conducive to light cooperation, assimilation products, easy to cause melon. The lack of water and fertilizer or the lack of trace elements due to improper fertilization also affected the photosynthesis.

4. parthenocarpy

The temperature difference between day and night in greenhouse seedling raising and later growing period is large, forming more female flowers and fewer male flowers. At this time, insects have not yet been able to activate less pollination media, and do not stop artificial pollination, then they are mainly unisexual fruiting, and the species with weak unisexual fruiting are easy to melon.

5. Overgrowth of stems and leaves

Because of the factors such as plentiful nitrogen, high night temperature, watering and fertilizing before root melon sitting, temporary empty seedling, and sufficient water and fertilizer supply for no melon on the plant as usual, the stem is thick and long, the leaves are thin and big, the growth of melon strips is slow, and the female flowers and young melons can not be assimilated.

6. Overgrowth of flowers and fruits

There are too many female flowers and young melons on the plant, and the limited assimilation products can only be distributed to the big melon or part of the female flowers and young melons, which will cause most of the female flowers and young melons to melon. If the melon below is not harvested in time, the melon above will melt away easily.

7. Severe pests and diseases

Downy mildew, bacterial keratoplaque, anthrax, powdery mildew, black star disease and so on, will directly harm the leaves, causing leaf necrosis, seriously causing the whole leaf or the whole plant leaves withered, unable to stop the use of light cooperation and melon. Beneficiary insects such as aphids, yellow tea mites and whitefly destroy photosynergism by absorbing juice from leaves of cucurbits and vegetables and polluting them, resulting in malnutrition and melon melon melon.

8. Drug damage

The irrational selection of pesticides, excessive concentration of pesticides or excessive spraying of pesticides can cause melons and vegetables to suffer from pesticide damage and aging, so that the photosynthesis of leaves can be reduced or even lost.

The article originated from Jiangmen Vegetable Distribution

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