How does high temperature affect vegetables
Today, let's introduce the knowledge about how high temperature affects vegetables in terms of花草草. Keep reading!
How does high temperature affect vegetables
High temperature can easily cause excessive growth of seedlings, especially after night temperatures are too high, leading to excessive growth, which affects the flowering, fruit setting, and yield of vegetables later on. High temperature and drought can worsen diseases such as viral diseases, powdery mildew, and mite infestations. Triazole, Wuyiycin, and Fuxing can be sprayed to control powdery mildew; miticides can be sprayed to control mite damage. Watering is one of the most effective measures to relieve high temperature, and the frequency of watering can be increased appropriately.
High temperature has an adverse effect on vegetable growth, which is the basic reason for the lack of vegetables in autumn. Except for a few heat-tolerant varieties such as wax gourd, pumpkin, bitter gourd, green bean pods, and spinach, most vegetables are not heat-tolerant.
In the midsummer season, not only cool-season vegetables like spinach, cabbage, radishes, and Dutch peas cannot grow, but warm-season vegetables like tomatoes and peppers are also not suitable for planting.
Moreover, high temperature with abundant rain or high temperature with drought can lead to the recurrence of various diseases and pests, causing significant yield reduction or even crop failure, exacerbating the occurrence of the autumn淡 season.
Ⅰ. The main hazards of high temperature on vegetable growth and development
Plant water lossWhen the temperature is above 30℃, if there is no rain or little rain, it will cause soil drought and atmospheric drought.
When the water absorbed by the vegetable roots from the soil cannot meet the plant's evaporation demand, it will cause the leaves of the vegetable plants to curl and fall off, resulting in poor quality, reduced yield, and even withering and death.
Excessive growth of plantsHigh temperature can easily cause excessive growth of seedlings, especially after night temperatures are too high, leading to excessive growth, which affects the flowering and fruit setting of vegetables and yield.
Effect on bud differentiation and sex differentiationHigh temperature and long-daylight hours increase the number of male flowers in cucumbers and delay the differentiation of female flowers. During the bud differentiation of tomatoes and peppers, fewer flowers develop and they are not well-developed under high temperatures.
Loss of disease resistanceWhen the air or soil temperature is higher than the normal growth range of vegetable plants, it will cause some disease-resistant varieties to lose their resistance and become susceptible varieties, thus aggravating the occurrence of diseases.
Susceptible to physiological diseasesHigh temperature often comes with strong sunlight. When the strong sunlight shines on the fruits of vegetables like eggplants and melons for a long time, the sun-exposed side of the fruit can be sunburned, causing sunscald.
High temperature and drought can also adversely affect the flowering and fruiting process of vegetables such as eggplants and legumes, causing flower and fruit drop. Drought and water deficiency can easily cause diseases such as dry heart in Chinese cabbages and blossom-end rot in tomatoes.
Under high temperature, lycopene in tomatoes is difficult to form, so the fruits often show a mixture of yellow, red, and white colors, greatly reducing their commercial value.
Inducing various diseases and pestsHigh temperature and drought can worsen viral diseases, powdery mildew, and mite damage.
Ⅱ. Main measures to deal with high temperature damage
Interplanting with tall cropsTake full advantage of the shading effect of tall crops and properly match sun-loving and shade-loving crops. For example, planting eggplants and peppers together, corn and peppers together, and intercropping ginger in mulberry, tea, and orchard shade areas.
Timely shading and coolingIn summer and autumn seedlings, it is best to set up shade sheds to block sunlight. When planting leafy vegetables in summer and autumn, it is best to set up sheds covered with sunshade nets to prevent sunburn and pests. For open-field sweet peppers, sheds can be set up and covered with sunshade nets to prevent sunburn and diseases.
On the protective shed film, sunshade nets can be covered or mud slurry can be applied to prevent sunburn. For bare crop rows, a layer of wheat straw, rice straw, chopped straw, etc., can be spread on the ground to prevent the soil temperature from getting too high. To prevent the covering material from being washed away by watering, some soil can be pressed on it.
For vegetables exposed to sunlight, some weeds, old newspapers, etc., can be covered on them to prevent sunburn on the fruit.
Utilize the leaves to shade and prevent sunburn In the high-temperature periods of summer and autumn, the leaves should be fully utilized to shade and protect the fruit.
For example, when pinching off the tops of tomato plants, two layers of leaves should be left above the top layer of fruit to shade the young tomatoes from sunlight; after the cabbage is 80% mature and the cauliflower has formed a head, the outer leaves can be picked and covered on the head to prevent sunburn and improve quality.
In summer and autumn vegetable cultivation, dense planting is generally preferred over sparse planting to provide mutual shading and benefit growth.
Reasonable wateringWatering is one of the most effective measures to alleviate high temperature, and the frequency and amount of watering can be increased appropriately. Sprinkler irrigation or spraying water on the leaves can be used to prevent leaf dehydration, if conditions allow.
The timing should be in the early morning or evening, and it is strictly forbidden to water at noon when the temperature is high. Well water or low-temperature river water should be used for irrigation, and the soil should be watered evenly and thoroughly to keep it moist. After a hot thunderstorm, it is necessary to drain the water and irrigate with cool water to prevent heat injury.
Timely topdressingAccording to the type of vegetable crops and their growth stage, topdress fertilizers in conjunction with watering, but do not apply human waste. Nitrogen, phosphorus, and potassium fertilizers should be applied in combination, such as using nitrogen fertilizer as the main source and phosphorus and potassium fertilizers as supplements during the seedling stage; and using phosphorus and potassium fertilizers as the main source and nitrogen fertilizers as supplements during the fruit-setting stage.
Topdress once during the seedling stage, initial fruiting stage, and full fruiting stage. When the leaves are yellow and weak, a 0.1%-0.2% phosphorus acid hydrogen potassium solution, sprayable treasure, and Ainong can be sprayed on the leaves to promote vegetable growth and prevent early leaf senescence.
Especially after a hot thunderstorm, it is necessary to strengthen the cultivation of the soil and apply fast-acting chemical fertilizers in a timely manner.
Syndromic control of diseases and pestsFrom the initial flowering stage of tomatoes or the rosette stage of Chinese cabbages, a mixture of calcium chloride and naphthylacetic acid can be sprayed to prevent blossom-end rot or dry heart disease.
Plant growth regulators such as naphthylacetic acid, fall prevent, and 2, 4-D can be used to treat the flowers of solanaceous or leguminous plants to prevent flower and fruit drop; virus A, plant disease灵, and Fungus-toxin clear can be sprayed to prevent viral diseases.
Triazole, Wuyiycin, and Fuxing can be sprayed to control powdery mildew; miticides can be sprayed to control mite damage. It is important to note that vegetables sprayed with pesticides should be listed for sale after the safety interval to avoid affecting human health.
The above is a detailed introduction to how high temperature affects vegetables. Did you get it?