How to prevent and control jujube tree rust disease? Mastering integrated control techniques is key
Jujube rust disease, also known as jujube mist, often causes massive leaf drop during the fruit expansion stage. Diseased trees produce shriveled jujube fruits with reduced sugar content in the flesh, most of which are inedible. Due to the damage caused by rust disease, serious yield reductions occur, variety quality deteriorates, and farmers' economic income is directly affected. Severely diseased trees that drop leaves early will sprout a second time, affecting the...
Jujube rust disease, also known as jujube mist, often causes massive leaf drop during the fruit expansion stage. Diseased trees produce shriveled jujube fruits with reduced sugar content in the flesh, most of which are inedible. Due to the damage caused by rust disease, serious yield reductions occur, variety quality deteriorates, and farmers' economic income is directly affected. Severely diseased trees that drop leaves early will sprout a second time, affecting the following year's yield. Therefore, integrated measures must be adopted for early prevention and control to minimize the losses caused by the disease.
Jujube rust disease begins to occur in early July, breaks out in large numbers after August, and continuously reinfects, causing massive leaf drop. In terms of control, it is important to focus on agricultural control as the primary approach and chemical control as supplementary, seize the favorable control period, improve control effectiveness, and reduce disease occurrence.
Thorough orchard cleaning: Carry out orchard cleaning every late autumn, remove diseased fruits and diseased leaves remaining on the trees, sweep up fallen leaves and fallen fruits under the trees, and burn or deeply bury them in a centralized manner to reduce overwintering pathogens. At the same time, carry out deep winter plowing to deeply bury pathogens and dig out some pests so that birds can eat them or they freeze to death. This also improves soil physical and chemical properties, creating conditions for healthy growth of jujube trees.
Scientific fertilization: According to surveys, jujube orchards with poor soil fertility, weakened tree vigor, low yield, and poor quality have severe occurrences of jujube rust disease. Therefore, scientific fertilization should be carried out to build up soil fertility, provide sufficient nutrients for the growth and development of jujube trees, and improve the disease resistance of jujube trees. In terms of fertilization, emphasis should be placed on applying base fertilizer, mainly organic fertilizer, combined with phosphorus and potassium fertilizers; spraying flower fertilizer, mainly foliar fertilizer during the flowering period, with 0.3%-0.5% potassium dihydrogen phosphate solution; and supplementary fruit-promoting fertilizer, mainly a combination of quick-acting nitrogen, phosphorus, and potassium fertilizers.
Eliminate standing water: Long-term standing water in jujube orchards can cause jujube fruits to drop, massive root death, and worsened jujube rust disease. Therefore, in low-lying areas prone to water accumulation, drainage should be carried out promptly during the rainy season. Also, carry out timely deep intertillage to loosen the soil in the orchard, promote root activity, reduce orchard humidity, and alleviate the occurrence and damage of rust disease.
Rational pruning: For jujube orchards with excessive planting density and vigorous growth, appropriate pruning should be carried out to facilitate ventilation and light penetration, strengthen tree vigor, and improve the disease resistance of the tree body. Pruning should focus mainly on thinning branches. New jujube heads sprouting from jujube spurs and new jujube heads sprouting within the canopy should be promptly removed if not needed, to reduce nutrient consumption, improve ventilation and light conditions, resist rust disease occurrence, increase fruit set rate, and enhance fruit quality.
Chemical control: Mainly spray 200-fold Bordeaux mixture once in early July for protection. Spray 200-fold Bordeaux mixture again in early August. Alternatively, use 70% thiophanate-methyl wettable powder at 800-fold solution for spray control to control the occurrence and spread of jujube rust disease.