Ecological requirements of flowers and fruits of pollution-free cucumbers
Ecological requirements of flowers and fruits of pollution-free cucumbers
Cucumber flowers are divided into female flowers and male flowers, with a few being bisexual flowers. Female flowers are the basis for yield formation; their time of differentiation, number and quality are related to the variety and also to environmental factors. Under conditions of adequate water and fertilizer, a relatively low night temperature of 10-12°C and a short daylength of about 8 hours promote female flower differentiation, can increase the number of female flowers, and lower the node position at which female flowers are borne; excessively high night temperature and a 12-hour long daylength promote male flower differentiation. If the seedbed is not exposed to light day and night, or the light hours are artificially prolonged, female flower differentiation is instead affected, resulting in few or even no cucumbers in the early stage after transplanting. Plant hormones can also control the sex differentiation of cucumber flower buds. For example, ethephon at a concentration of 150-250 microliters/liter can promote female flower formation, while 0.1%-0.2% gibberellin can promote male flower formation. Summer and autumn cucumbers are in the high-temperature season during the seedling stage, so ethephon at a concentration of 150-250 microliters/liter can be sprayed at the 2-4 true leaf stage to promote female flower formation. In winter and spring, the seedling stage can satisfy the conditions of low night temperature and short daylength, so there is no need to spray ethephon (or cucumber-setting agent); otherwise, female flowers differentiate too many, causing severe fruit abortion during the fruiting period.
Cucumber has strong parthenocarpic ability, flowers and sets fruit continuously, and has a long fruiting period, with great yield potential. During the fruiting period, six major environmental factors (temperature, light, water, air, fertilizer, organisms) are required to be coordinated and supplied timely and in appropriate amounts, so as to ensure a balanced relationship between vines and fruits and achieve the goals of high yield, high quality and high efficiency.
In production, topdressing and irrigation with fruit-forcing water usually begin when the root cucumber has set or around the time of harvesting the root cucumber. If this water and fertilizer are applied too early, it easily causes excessive vine growth and fruit abortion; if too late, it affects fruit enlargement. After the fruit-forcing water and fertilizer, a sufficient and uniform supply of water and fertilizer must be ensured. During the fruiting period, four-stage variable temperature management is used: on sunny days, 25-28°C in the morning, 25-20°C in the afternoon, 18-15°C in the first half of the night (favorable for photosynthesis transport), and 15-13°C in the second half of the night (reducing respiratory consumption); on cloudy days, the daytime temperature is lower than on sunny days, and the nighttime temperature is about 10°C. If light is weak, the temperature should also be appropriately lowered; during the fruiting period, artificial carbon dioxide fertilization is beneficial for increasing yield and income. During the fruiting period, if environmental factors are unsuitable or pests and diseases are severe, the plants are prone to premature aging or excessive vegetative growth, cucumber fruits grow slowly, and abnormal fruits such as deformed cucumbers, aborted fruits, and bitter cucumbers may even appear.
Cucumber has strong parthenocarpic ability, flowers and sets fruit continuously, and has a long fruiting period, with great yield potential. During the fruiting period, six major environmental factors (temperature, light, water, air, fertilizer, organisms) are required to be coordinated and supplied timely and in appropriate amounts, so as to ensure a balanced relationship between vines and fruits and achieve the goals of high yield, high quality and high efficiency.
In production, topdressing and irrigation with fruit-forcing water usually begin when the root cucumber has set or around the time of harvesting the root cucumber. If this water and fertilizer are applied too early, it easily causes excessive vine growth and fruit abortion; if too late, it affects fruit enlargement. After the fruit-forcing water and fertilizer, a sufficient and uniform supply of water and fertilizer must be ensured. During the fruiting period, four-stage variable temperature management is used: on sunny days, 25-28°C in the morning, 25-20°C in the afternoon, 18-15°C in the first half of the night (favorable for photosynthesis transport), and 15-13°C in the second half of the night (reducing respiratory consumption); on cloudy days, the daytime temperature is lower than on sunny days, and the nighttime temperature is about 10°C. If light is weak, the temperature should also be appropriately lowered; during the fruiting period, artificial carbon dioxide fertilization is beneficial for increasing yield and income. During the fruiting period, if environmental factors are unsuitable or pests and diseases are severe, the plants are prone to premature aging or excessive vegetative growth, cucumber fruits grow slowly, and abnormal fruits such as deformed cucumbers, aborted fruits, and bitter cucumbers may even appear.