Key Points of Early-Maturing Cultivation Techniques for Eggplant in Greenhouses

Eggplant, also known as “qie”, with the alternative name “luosu”, is one of the few purple vegetables and is also a very common home-cooked vegetable on the dining table. In some areas of Jiangsu, Zhejiang and Anhui it is called luosu, while in Guangdong and Guangxi it is called aigua. It is an annual herbaceous plant of the genus Solanum in the nightshade family, and is perennial in the tropics. Its fruit is edible, and the color is mostly purple or purplish-black, though there are also light green or white varieties, and the shapes include round, oval, pear-shaped and various others.

Eggplant is also fairly rich in nutrients, containing protein, fat, carbohydrates, vitamins, as well as calcium, phosphorus, iron and many other nutrients. In particular, its content of vitamin P is very high. Every 100 grams contains 750 mg of vitamin P, which many vegetables and fruits cannot match. Vitamin P can keep blood vessel walls elastic and preserve their physiological function, preventing hardening and rupture, so eating eggplant regularly helps prevent and treat high blood pressure, coronary heart disease, arteriosclerosis and hemorrhagic purpura. Vitamin P can keep blood vessel walls elastic and preserve their physiological function, protecting the cardiovascular system and acting against ascorbic acid; this substance can enhance the adhesion between human cells, strengthen the elasticity of capillaries, reduce the fragility and permeability of capillaries, prevent microvessel rupture and bleeding, keep the cardiovascular system functioning normally, and prevent hardening and rupture, so eating eggplant regularly helps prevent and treat high blood pressure, coronary heart disease, arteriosclerosis and hemorrhagic purpura. Protecting the cardiovascular system and acting against ascorbic acid: in addition, eggplant also has the effect of preventing and treating scurvy and promoting wound healing.

How can eggplant be cultivated in a greenhouse for early maturity?

Seed selection and seedling raising:

For protected cultivation of eggplant in early spring, early-maturing, high-yielding, disease-resistant and high-quality green eggplant varieties should be selected. For example, Zhoukou Waibacao and Xinxiang Caoqingqie. These two varieties generally form flower buds at 7 leaves and are suitable for dense planting. When grown as seedlings with heating wires in a greenhouse, the seedling age is 90-100 days, and it is best to transplant when they have 7-8 leaves and have formed large buds. If transplanted when the seedling age exceeds 120 days, there will be slow seedling recovery, the first eggplant is prone to dropping, and although flowering begins early, the early yield is low. If the seedling age is less than 80 days, the initial flowering period is too late and the early yield decreases. Temperature is the key to cultivating strong seedlings. Under suitable low temperatures, the differentiated flower buds are positioned at lower nodes and the proportion of long-styled flowers is greater. The daytime temperature should be between 20°C and 25°C, the nighttime temperature between 15 and 17°C, and the soil temperature above 15°C. During the seedling period, when there are 2 leaves and 1 heart leaf, thin the seedlings once, with a nutrient area of 100 sq cm per plant. Before transplanting, cut and turn the soil blocks, and harden the seedlings at low temperature. Cultivation management:

In early spring, when the soil temperature at a depth of 10 cm in the greenhouse steadily reaches 10°C, open a 15 cm deep furrow according to the row spacing, lay one heating wire at the bottom, cover with 5 cm of soil, and water thoroughly so that the soil temperature rises above 12°C. Choose a sunny noon to water with dark water and transplant the eggplant seedlings, cover with a small arch shed at night and remove it during the day. In eastern Henan, transplanting should be done in late February. The on-off time of the heating wire should be controlled flexibly. Before seedling recovery, turn it off during the day and on at night; after seedling recovery, turn it on in the middle of the night when there is a cold wave, and turn it off when there is no cold wave. To increase the early yield, the planting density is 4000 plants, with a plant and row spacing of 33 cm × 50 cm. This can increase the early yield by about 25%. In the early stage in the greenhouse, the temperature is low and the light is poor, while in the later stage the temperature is high and the proportion of short-styled flowers is large, so under conditions without insect pollination it is easy for flowers to drop. Therefore, when the first eggplant and the opposite eggplant flower, dipping the flowers with 20-25 ppm of 2,4-D or 40-50 ppm of Zuoguoling can make the fruit-setting rate reach more than 85%.

Evaporation in the greenhouse is low, and the temperature in early spring is low, so the number of waterings should be as few as possible. Before transplanting, water heavily once along the furrow, watering enough to soak through. Water once at transplanting, watering first and then covering with soil. When the eggplant grows to the size of an egg, choose a sunny day to water once with fruit-promoting water, and apply one fruit-promoting fertilizer along with the water. Apply 10 kg of urea or 1500 kg of decomposed human and animal manure per mu. Water less at other times. Eggplant branching increases in multiples of 2, so when dense cultivation is practiced, the structure must be adjusted promptly. After the eggplant is harvested, remove 1 row every 2 rows. For the rows that are thinned out, after the opposite eggplant has set, leave 2 leaves above it and pinch off the growing tip. For the retained rows, promptly remove old leaves and prune empty branches to maintain a reasonable population. From 7 days before transplanting until seedling recovery, do not ventilate. From transplanting until seedling recovery, the soil temperature should be kept above 15°C to promote rapid seedling recovery. When the first eggplant grows to the size of an egg, choose a sunny day to water with fruit-promoting water, do not ventilate that day, and ventilate promptly afterward to reduce humidity in the greenhouse. After the first eggplant is harvested, gradually increase the amount of ventilation. When ventilating, first ventilate at the top, then at the sides; begin by ventilating at noon on sunny days, then transition to all-day ventilation; first ventilate during the day, then transition to ventilating at night as well. Keep the daytime temperature in the greenhouse at 25-30°C, not exceeding 35°C and not below 20°C; keep the nighttime temperature at 15-17°C. Pest and disease control:

Phytophthora blight, brown spot disease and Verticillium wilt are the three major diseases in eggplant cultivation, and in continuous cropping land Verticillium wilt causes the most serious damage. During cultivation, cultivate less and shallowly, damage the roots less, ventilate more, appropriately control the amount of watering, save seed from disease-free plants, rotate once with allium and garlic crops within 3-4 years to reduce the amount of soil-borne pathogens, soak the seeds for 2 hours with a 500-fold solution of 50% carbendazim wettable powder, then soak the seeds with 10 ppm of 10% naphthaleneacetic acid liquid, water the thinning seedlings with a 500-fold solution of 50% thiophanate-methyl wettable powder; mix 50% carbendazim wettable powder with 10 times the amount of soil and spread it in the sowing bed and transplanting furrow, using 30 grams of medicated soil per sq m, and before disease onset spray the leaf surface 2-3 times with a 5 ppm solution of 10% naphthaleneacetic acid, spraying once every 10-15 days. During the occurrence period of Phytophthora blight and ring rot disease, spray the leaf surface twice with a 600-fold solution of 75% chlorothalonil wettable powder or a 1000-fold solution of 48% Ruikumai, once every 5 days. During the occurrence period of Verticillium wilt, drench the roots with a 600-fold solution of Kangkuning or an 800-fold solution of 48% Ruikumai, which can effectively control the spread of the disease.