How to prevent and control deformed and hollow tomatoes?
Prevention and control methods for deformed and hollow tomatoes
In greenhouses, tomatoes are highly prone to deformed fruit and hollow fruit, with some plants affected at a rate above 50%, and in some cases the entire first cluster of tomatoes in a whole greenhouse is deformed or hollow, delaying the marketing period and reducing both yield and quality.
I. Symptoms
Deformed fruit: Tomato fruits develop a pointed, peach-like tip, irregular swelling, large areas of corky scarring on the skin, or split fruit with exposed seeds.
Hollow fruit: A cavity forms between the tomato skin and the gelatinous pulp, and the fruit takes on an angular, multi-ridged appearance.
II. Causes
1. Causes of deformed fruit: These are mainly caused by improper management during the seedling stage. Whether a tomato fruit develops normally depends on the quality of flower bud differentiation. The differentiation period of the 1st to 3rd clusters occurs during the seedling stage from 2-3 true leaves to 7-8 true leaves. If winter seedling raising is mismanaged, flower bud differentiation is poor under weak light and night temperatures below 10°C; if the temperature is low while water is plentiful and nitrogen fertilizer is excessive, flower buds tend to over-differentiate, forming multi-ridged fruit; if the seedling age is prolonged and the seedling stage is cold and dry, the seedlings remain in a suppressed state, the floral organs tend to become corky, and after fruit set, scarred fruit and split fruit with exposed seeds form.
2. Causes of hollow fruit: These are mainly caused by improper management during the flowering and fruit-setting period. (1) The effect of fruit-setting hormones. Spraying hormones such as 2,4-D and fruit-setting agents two days before flowering causes the skin to develop quickly while the placenta develops poorly, resulting in a cavity forming near the skin inside the ovary; using fruit-setting hormones at too high a concentration or on cloudy and snowy days can also cause hollow fruit; (2) A prolonged period of low temperature and weak light during fruit set reduces photosynthetic products, so the supply of nutrients transported to the fruit falls short of demand; (3) Large-fruited varieties with high fertilizer requirements, such as Maofen 802, cannot be supplied with enough fertilizer; (4) Insufficient watering during fruit set hinders fruit growth and development.
III. Prevention and control methods
1. Prevention and control of deformed fruit (1) During seedling raising, maintain a daytime temperature of 20-25°C and a nighttime temperature of 13-17°C to prevent temperatures below 10°C, which cause deformed flowers. (2) When seedlings become leggy, do not rely solely on lowering temperature and drought to control the seedlings. While maintaining a suitable temperature, appropriately control water and spray 85% daminozide soluble powder at 2000 mg/kg, or spray chlormequat at 1000-1500 mg/kg; this can control leggy growth without affecting normal flower bud differentiation. (3) Deformed fruit cannot develop into normal fruit and should be removed as early as possible to reduce nutrient consumption and promote the growth of other flowers and fruits.
2. Prevention and control of hollow fruit (1) Use fruit-setting hormones properly. Especially at low temperatures in early spring, wait until the flowers have opened before spraying hormones. Alternatively, after the flowers open, first vibrate the flowers to promote pollination and then treat them with hormones, which can prevent flower drop and promote normal fruit enlargement. When using hormones such as 2,4-D, prepare the concentration appropriately, and note that they should be used in the morning or afternoon and on sunny days. (2) For large-fruited varieties such as Maofen 802, water and fertilize promptly during the flowering and fruit-setting period to prevent malnutrition caused by a lack of fertilizer and water. (3) For early spring tomatoes after flowering and fruit set, if there is a prolonged period of low temperature and cloudy, snowy weather, increase the temperature promptly and keep the nighttime temperature above 13°C. (4) Fruit with mild hollowness can be encouraged to ripen normally by strengthening fertilizer and water management. Fruit with severe hollowness should be removed as early as possible to avoid consuming nutrients.
I. Symptoms
Deformed fruit: Tomato fruits develop a pointed, peach-like tip, irregular swelling, large areas of corky scarring on the skin, or split fruit with exposed seeds.
Hollow fruit: A cavity forms between the tomato skin and the gelatinous pulp, and the fruit takes on an angular, multi-ridged appearance.
II. Causes
1. Causes of deformed fruit: These are mainly caused by improper management during the seedling stage. Whether a tomato fruit develops normally depends on the quality of flower bud differentiation. The differentiation period of the 1st to 3rd clusters occurs during the seedling stage from 2-3 true leaves to 7-8 true leaves. If winter seedling raising is mismanaged, flower bud differentiation is poor under weak light and night temperatures below 10°C; if the temperature is low while water is plentiful and nitrogen fertilizer is excessive, flower buds tend to over-differentiate, forming multi-ridged fruit; if the seedling age is prolonged and the seedling stage is cold and dry, the seedlings remain in a suppressed state, the floral organs tend to become corky, and after fruit set, scarred fruit and split fruit with exposed seeds form.
2. Causes of hollow fruit: These are mainly caused by improper management during the flowering and fruit-setting period. (1) The effect of fruit-setting hormones. Spraying hormones such as 2,4-D and fruit-setting agents two days before flowering causes the skin to develop quickly while the placenta develops poorly, resulting in a cavity forming near the skin inside the ovary; using fruit-setting hormones at too high a concentration or on cloudy and snowy days can also cause hollow fruit; (2) A prolonged period of low temperature and weak light during fruit set reduces photosynthetic products, so the supply of nutrients transported to the fruit falls short of demand; (3) Large-fruited varieties with high fertilizer requirements, such as Maofen 802, cannot be supplied with enough fertilizer; (4) Insufficient watering during fruit set hinders fruit growth and development.
III. Prevention and control methods
1. Prevention and control of deformed fruit (1) During seedling raising, maintain a daytime temperature of 20-25°C and a nighttime temperature of 13-17°C to prevent temperatures below 10°C, which cause deformed flowers. (2) When seedlings become leggy, do not rely solely on lowering temperature and drought to control the seedlings. While maintaining a suitable temperature, appropriately control water and spray 85% daminozide soluble powder at 2000 mg/kg, or spray chlormequat at 1000-1500 mg/kg; this can control leggy growth without affecting normal flower bud differentiation. (3) Deformed fruit cannot develop into normal fruit and should be removed as early as possible to reduce nutrient consumption and promote the growth of other flowers and fruits.
2. Prevention and control of hollow fruit (1) Use fruit-setting hormones properly. Especially at low temperatures in early spring, wait until the flowers have opened before spraying hormones. Alternatively, after the flowers open, first vibrate the flowers to promote pollination and then treat them with hormones, which can prevent flower drop and promote normal fruit enlargement. When using hormones such as 2,4-D, prepare the concentration appropriately, and note that they should be used in the morning or afternoon and on sunny days. (2) For large-fruited varieties such as Maofen 802, water and fertilize promptly during the flowering and fruit-setting period to prevent malnutrition caused by a lack of fertilizer and water. (3) For early spring tomatoes after flowering and fruit set, if there is a prolonged period of low temperature and cloudy, snowy weather, increase the temperature promptly and keep the nighttime temperature above 13°C. (4) Fruit with mild hollowness can be encouraged to ripen normally by strengthening fertilizer and water management. Fruit with severe hollowness should be removed as early as possible to avoid consuming nutrients.