Management methods for grapefruit flowering period
Pomelo enters its full flowering period from April to May every year. Management at this stage directly affects fruit quality and yield. Many growers often lose flowers and fruits due to neglect flowering maintenance. How to achieve high yield goals through systematic management? This article will deeply analyze the three core dimensions of pomelo tree flowering management. Pomelo tree shaping and pruning technology The flower branch screening principle For old trees over 5 years old, it is recommended to retain strong flower branches with a diameter of ≥ 0.8 cm. Reserve 15-20 fruiting mother branches per square meter of crown, and follow the principle of "removing the weak and retaining the strong" to cut off crossing branches, pest and disease branches and excessively dense branches. Special attention should be paid to retaining the southeastern branches to ensure transparent light. The crown shaping specification adopts the natural open-center pruning method, and the opening angle of the main branch is controlled at 45-60 degrees. The spacing between each layer shall be maintained at 50-60cm, and the top truncation height shall not exceed 3 meters. After pruning, the light transmission rate of the crown should reach more than 30% to ensure the normal development of inner chamber branches. The operation points of picking the top of spring shoots 2-3 times, retaining 8 leaves when the tip length is 15cm for the first time, and the interval between the second picking is 20 days. Combined application of 0.2% potassium dihydrogen phosphate solution can promote the thickening of lateral branches by 20%-30%. The trace element ratio plan for the nutritional control system during flowering period requires supplementing boron-zinc-iron compound fertilizer during flowering period. The recommended formula is 0.1% borax +0.05% zinc sulfate +0.02% iron EDTA. Foliar spraying should be completed before 10 a.m., focusing on the back of the flower ears, and applying it twice continuously at an interval of 7 days. Collaborative management of water and fertilizer uses drip irrigation systems to maintain soil water content at 60%-70%, combined with the application of high-phosphorus water-soluble fertilizers (N:P:K=10:40:10). Pay attention to alternating rhizosphere fertilization and foliar topdressing to avoid fertilizer damage. The branch renewal strategy selects summer shoots with a diameter of 0.6- 0.8 cm as preparation branches, and each plant retains 3-5 strong new shoots. Spiral binding method is used to guide the spatial distribution of branches, and indolebutyric acid is applied to promote lignification. During the key control period of comprehensive pest and insect pest prevention and control, the bud stage, full flowering stage, and dead flowering stage are the three major control nodes. Focus on monitoring the occurrence of thrips, red spider and (T-J) diseases, and it is recommended to use a compound preparation of spinosad + difenoconazole. Biological control technology hangs 30 insect trapping yellow boards per mu, and arranges 10 frequency-vibrating insecticidal lights at intervals. Release Amblyseius cucuris to control the red spider population, and maintain the benefit-to-harm ratio of 1:50 to achieve the best prevention and control effect.
Flowering management is the prime time for the anniversary management of pomelo trees. Through the trinity management model of precise pruning, scientific fertilizer supplementation, and three-dimensional prevention and control, the fruit setting rate can be significantly increased by 15%-20%. It is recommended that growers establish a flowering management log to record daily temperature and humidity, farming operations and tree responses, laying a foundation for sustainable high yields.