High-yield and high-efficiency cultivation method for camellia oleifera

Abstract

The invention discloses a high-yield and high-efficiency cultivation method for camellia oleifera, and belongs to the technical field of agricultural planting. The cultivation method comprises the steps of variety configuration, field planting management, sapling management, adult tree management and flower and fruit retention, high and stable yield of camellia oleifera is achieved through the measures of scientific management, soil improvement, scientific pruning, on-demand fertilization, flower and fruit retention and the like in the whole growth period of camellia oleifera, and the yield and quality are improved.

Description

Technical Field

[0001] The invention relates to a high-yield and high-efficiency cultivation method for oil-tea camellia, in particular to a high-yield and high-efficiency cultivation method for oil-tea camellia based on the climate of Hunan. Background Art

[0002] Camellia oleifera is a woody oil plant unique to southern my country. It is a healthy and high-end edible oil that is deeply loved by the vast southern region. However, it is basically planted in barren mountains and other places. There is a lack of management and effective management technology. For many years, it has been based on experience and imitation of other fruit trees. There is no scientific management based on the biological behavior and phenological period of Camellia oleifera, resulting in low yield and quality decline. In addition, Hunan and Jiangxi belong to the hilly and mountainous areas of Hunan. The annual rainy season and light distribution are uneven, resulting in annual management inconsistent with the biological period and phenological period of Camellia oleifera. In addition, modern agricultural reclamation measures such as full reclamation have caused a decrease in soil organic matter, resulting in low yield of Camellia oleifera, serious alternate years, and quality decline. Summary of the invention

[0003] In order to overcome the above-mentioned defects in the prior art, the present invention provides a high-yield and high-efficiency cultivation method for oil tea, which achieves high and stable yield of oil tea and improves yield and quality through scientific management of the entire growth period of oil tea, soil improvement, scientific pruning, fertilization on demand, and protection of flowers and fruits.

[0004] A high-yield and high-efficiency cultivation method for oil-tea camellia comprises the following steps:

[0005] (1) Variety configuration: Select two or three varieties with the same flowering period, ploidy, and maturity period, and plant them in alternate rows;

[0006] (2) Planting management: From April to May and / or July to August of the first to third year after planting, when the new shoots mature, prune them every year to induce summer and late summer shoots to sprout, and at the same time, add 50-100 g / plant of potassium nitrate compound fertilizer to the roots;

[0007] (3) Management of young trees: From the first to the third year after planting, when the new shoots mature in April-May and / or July-August, prune the lateral buds every year to induce the germination of summer shoots and late summer shoots to achieve rapid growth. At the same time, supplement the roots with potassium nitrate compound fertilizer 50-100 g / plant;

[0008] (4) Management of mature trees: Starting from the fourth year after planting, stop pruning in spring and focus on winter pruning. The principle is to keep the main branches sparse and the small branches dense. Only remove the lower branches, diseased and insect-infested branches, and cross branches, etc. Fertilize scientifically according to the tree vigor;

[0009] (5) Preserving flowers and fruits: Ensure flower bud differentiation in April and preserve flowers and fruits in November, including garden cleaning, artificial pollination, shaking flowers to prevent gray mold, and fertilizing to preserve fruits.

[0010] Preferably, the high-yield and high-efficiency oil-tea cultivation method described in the present invention is based on the climate of Hunan.

[0011] Preferably, the varieties in step (1) are two or three of Huaxin, Xianglin 210 or Huajin;

[0012] Preferably, the large seedlings in step (2) refer to those that have grown for 3-5 years after grafting and have a ground diameter greater than 0.8 cm. Planting with large seedlings can effectively remove rigid seedlings and reduce maintenance connections and costs. Further preferred are large seedlings that are 4 years old, free of pests and diseases, and growing vigorously.

[0013] Preferably, the large-hole planting and placement of high-carbon organic fertilizer in step (2) refers to a 60*60*60 cm square hole, and a three-layer model of organic fertilizer, topsoil, and planting soil is used to improve the soil, promote root growth, and accelerate the growth of tea trees. The organic fertilizer is preferably semi-mature plant-derived organic fertilizer, which can maintain the soil organic matter content for a longer period of time in the later stage and play a role in water conservation and heat preservation.

[0014] The removal of the seedling cup and pruning of the root system described in step (2) is to prevent the seedling cup from affecting the growth of the root system and causing root entanglement problems, and at the same time, it can remove pests and diseases and accelerate the germination of new roots.

[0015] The post-planting pruning described in step (2) refers to selecting 2-3 branches with different directions, vigorous growth, and an angle of less than 45 degrees to the vertical line at 20-30 cm immediately after planting, and further optimizing the selection of 2 strong branches with an angle of 30-45 degrees to the vertical, which can effectively reduce transpiration and improve the survival rate.

[0016] During the management of the young trees in step (3), mancozeb and Metarhizium muscardine are sprayed in early March to prevent anthracnose and leaf beetles.

[0017] The saplings in step (3) refer to oil tea trees that have grown within 1-3 years after planting. The sapling pruning is carried out in spring and summer, and is further optimized to select three strong main branches facing outward when the spring shoots mature in April and the summer shoots mature in June each year, and shorten 1-2 nodes to leave the outer buds; this is conducive to promoting the induction of new branches from new and old mature branches, promoting vegetative growth, inhibiting reproductive growth, avoiding the differentiation of flower buds of small trees and consuming nutrients, and accelerating the expansion of the tree crown. Drip irrigation or watering and fertilization are immediately carried out after each pruning, 50-100 grams per plant per time, and further optimized to 80 grams per plant per time according to the growth of the plant. The fertilizer type is potassium nitrate type high nitrogen compound water-soluble fertilizer, N:P 2 O 5 :K 2 O=10:3:2; at the same time, optimize the new shoots to be larger than 3cm each time, spray the new shoots with mancozeb to prevent the occurrence of diseases; and stop fertilizing in autumn to prevent frost damage.

[0018] The adult trees in step (4) are in the fourth year after the four-year-old seedlings are planted; the crown width is required to be greater than 2 meters and the height is greater than 1.5 meters; pruning: It is carried out after fruit picking and before flowering every year, and the tree shape is mainly open-heart shape and pagoda shape. Since the oil tea blooms and bears fruit in spring, and the fruit is small, it is necessary to retain enough fruiting mother branches, and the method of cutting large branches and leaving more small branches is adopted, mainly retaining 5-8 level branches. Branches exceeding level 12 need to be cut back and rejuvenated. Pruning is further optimized to increase the number of fruiting branch groups and reduce the influence of the level on nutrient transport, and the branch level is controlled at level 6-7.

[0019] Step (5) of the fruit-preserving fertilization: The best time for fertilization is from 15 days before fruit picking to 15 days before flowering, and the further optimized time is 20-15 days before flowering, which can prevent the fruit from being too green and ripening late, and can also supplement nutrition for flowering to retain the time for nutrient absorption and conversion; low-nitrogen, high-phosphorus and medium-potassium compound fertilizer is used as the main fertilizer, and the fertilizer is supplemented at a ratio of 0.5-1% of the amount of fruit picked. The specific ratio depends on the tree vigor: the vigorous tree is based on N:P 2 O 5 :K 2 O=1:3:2, the moderate tree follows N:P 2 O 5 :K 2 O = 1:2:1, weak tree follows N:P 2 O 5 :K 2 O=1:1:1, nitrogen fertilizer is mainly ammonium nitrogen. At the same time, 15-20 kg of organic fertilizer should be applied in the ditch during the period of 2-3 years, and mix well after application in the ditch.

[0020] Step (5) of flower and fruit preservation is the management of the whole growth period of Camellia oleifera from flower bud differentiation to pollination and fruit setting every year; strengthening water supply to adult trees at the end of February to promote the awakening of new roots, which is conducive to the growth of strong spring shoots in March; when the new shoots mature in April, water and fertilizer are controlled, and fertilizer is applied accurately according to the tree vigor to promote flower bud differentiation and supplement N:P for weak trees. 2 O 5 :K 2 O = 1:1:1 nitrate nitrogen fertilizer 300-500 g / plant, moderate trees according to N:P 2 O 5 :K 2 O = 1:2:1, 100-200 g of ammonium nitrate nitrogen fertilizer per plant, strictly control fertilization during vigorous growth; in early June, the physiological differentiation of flower buds is completed, and the young fruits enter a period of rapid expansion. Also, according to the weak tree fertilizer N:P 2 O 5 :K 2O = 1:1:1 ammonium nitrate nitrogen fertilizer 150-200 g / plant; prune during flowering period, and wash the pollen in water to obtain pollen, suspend the pollen with 5% brown sugar and 0.1% boron fertilizer, and take pollen 3-4 days after flowering. If it is too early, the pollen cannot be dispersed, and if it is too late, the pollen vitality decreases; dilute the picked pollen with 5% brown sugar and 0.1% boron fertilizer nutrient solution, and carry out liquid pollination, which can be done manually or by drone, and pollinate 2-3 times; use drones to fly low and blow the flowers after the flowers wither to reduce gray mold; 15 days after the flowers wither, supplement 0.3% potassium dihydrogen phosphate, 0.01% boron calcium zinc, and brassinolide (determined by the commercial dilution multiple) to promote cell division and achieve fruit preservation.

[0021] All the weeding work not listed above is routinely done once in June and at the end of September each year, just like traditional farming work, so I will not go into details.

[0022] Based on the above technical solution, the present invention has the following technical effects:

[0023] The present invention provides a high-yield and high-efficiency cultivation method of oil-tea based on the climate of Hunan:

[0024] 1. Adopt deep fertilization to improve soil and increase the organic matter content of Hunan red soil and reduce the cost of trenching and fertilization in the later stage;

[0025] 2. Changing the traditional autumn and winter pruning method can effectively shorten the growth period by 2-3 years, and at the same time save fertilizer costs by applying fertilizers as needed according to the growth volume;

[0026] 3. Alternative bearing can be avoided through promoting growth in spring shoots and managing flower bud differentiation; measures to preserve flowers and fruits can reduce flower and fruit drop during the autumn and winter rainy seasons in Hunan Province, increase yield by more than 40%, and keep the tree vigor stable and prevent premature aging. DETAILED DESCRIPTION

[0027] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0028] Young tree management

[0029] Example 1

[0030] Select 4-year-old Xianglin 210 seedlings, with a height of 118-122cm, a crown width of 110-120cm, and a ground diameter of 0.8-1.0cm. Dig a large hole and bury 20 kg of organic fertilizer rapeseed cake per plant. The hole size is 60*60*60CM square. Use a three-layer model of organic fertilizer, topsoil, and planting soil. Remove the seedling cup before planting, trim the root system, plant in mid-November, and prune after planting. Keep 2-3 branches at 20-30 cm in different directions and 30-45 degrees to the vertical direction. Shorten and expand the crown in April when the spring shoots mature and in June when the summer shoots mature from the first to the third year after planting; immediately add water and apply potassium nitrate type high nitrogen compound water-soluble fertilizer N:P after each pruning. 2 O 5 :K 2 O = 10:3:2, 80 g / plant / time;

[0031] Example 2

[0032] Select 4-year-old Xianglin 210 seedlings, with a height of 118-122cm, a crown width of 110-120cm, and a ground diameter of 0.8-1.0cm. Dig a large hole and bury 20 kg of organic fertilizer rapeseed cake per plant. The hole size is 60*60*60CM square. Use a three-layer model of organic fertilizer, topsoil, and planting soil. Remove the seedling cup before planting, prune the root system, and plant in mid-November. Prune after planting, and keep 2-3 branches at 20-30 cm in different directions and 30-45 degrees to the vertical direction. From the first to the third year after planting, only prune and expand the crown when the spring shoots are mature in April each year; immediately add water and apply potassium nitrate type high nitrogen compound water-soluble fertilizer N:P after each pruning. 2 O 5 :K 2 O = 10:3:2, 80 g / plant / time;

[0033] Example 3

[0034] Select 4-year-old Xianglin 210 seedlings, with a height of 118-122cm, a crown width of 110-120cm, and a ground diameter of 0.8-1.0cm. Dig a large hole and bury 20 kg of organic fertilizer rapeseed cake per plant. The hole size is 60*60*60CM square. Use a three-layer model of organic fertilizer, topsoil, and planting soil. Remove the seedling cup before planting, trim the root system, and plant in mid-November. Prune after planting, and keep 2-3 branches at 20-30 cm in different directions and 30-45 degrees to the vertical direction. From the first to the third year after planting, only prune and expand the crown when the summer shoots are mature in June each year; immediately add water and apply potassium nitrate type high nitrogen compound water-soluble fertilizer N:P after each pruning. 2 O 5 :K 2 OO=10:3:2, 80g / plant / time;

[0035] Comparative Example 1

[0036] Select 4-year-old Xianglin 210 seedlings, with a height of 118-122cm, a crown width of 110-120cm, and a ground diameter of 0.8-1.0cm. Dig a large hole and bury 20 kg of high-carbon organic fertilizer per plant. The hole size is 60*60*60CM square. Use a three-layer model of organic fertilizer, topsoil, and planting soil. Remove the seedling cup before planting, trim the root system, and plant in mid-November. Prune after planting, retaining 2-3 branches at 20-30 cm in different directions and 30-45 degrees to the vertical direction. Prune and expand the crown every winter from the first to the third year after planting; immediately add water and apply potassium nitrate-type high-nitrogen compound water-soluble fertilizer N:P after each pruning. 2 O 5 :K 2 O = 10:3:2, 80 g / plant / time;

[0037] Comparative Example 2

[0038] Select 4-year-old Xianglin 210 seedlings with a height of 118-122cm, a crown width of 110-120cm, and a ground diameter of 0.8-1.0cm. Plant directly without digging large holes. Remove the seedling cups before planting, trim the roots, plant in mid-November, and trim after planting. Keep 2-3 branches at 20-30cm in different directions with an angle of 30-45 degrees to the vertical direction. Do not trim for the first 3 years after planting.

[0039] The measurement is carried out in winter every year. 20 trees are selected from each case to measure their plant height, crown width and ground diameter. The plant height and crown width are measured with a ruler, and the ground diameter is measured with a vernier caliper. The corresponding average values ​​are taken and the corresponding tree vigor conditions are recorded. See Table 1 for details.

[0040] Table 1

[0041]

[0042] Through case comparison: planting in large holes and burying organic fertilizer deeply can effectively improve tree vigor and avoid premature aging; two prunings can accelerate crown expansion and thicken trunks; and the requirements of mature fruit-bearing trees can be reached in three years.

[0043] Management of mature fruit bearing trees

[0044] Example 4

[0045] After the four-year-old seedlings are planted, the crown width is required to be greater than 2 meters and the height is greater than 1.5 meters in the first three years based on the above seedling management. Starting from the fourth year, the whole garden is watered once on February 20. Fertilization and irrigation are stopped from the end of March to mid-April. Mancozeb is sprayed on the leaves once. The physiological differentiation of flower buds is completed in early June, and the young fruits enter the rapid expansion period. The weak trees are fertilized with N:P 2 O 5 :K 2O=1:1:1 ammonium nitrate nitrogen fertilizer 150-200g / plant; from July to September, appropriate irrigation is carried out according to climate requirements, and pruning is carried out once after fruit picking in November. The tree shape is mainly pagoda-shaped, and large branches are cut and more small branches are left. 6-7 level branches are retained, and the angle between the branches and the vertical line is 45-55 degrees; 20 days before flowering, low nitrogen, high phosphorus and medium potassium water-soluble fertilizer is applied once, and fertilizer is supplemented according to the ratio of 0.8% of the amount of fruit picked, according to N:P 2 O 5 :K 2 O=1:3:2; Thinning branches during the flowering period in mid-November, with ventilation and light transmission as the main pruning during the flowering period. At the same time, select the flowers obtained 3-4 days after flowering and put them into water to wash out the pollen. The pollen is suspended with 3% brown sugar and 0.1% boron fertilizer. The collected pollen is diluted with 5% brown sugar and 0.1% boron fertilizer nutrient solution for liquid pollination. It can be pollinated manually or by drone, and pollination is carried out 1-2 times; in late November, drones are used to fly low-altitude to blow the flowers after the flowers wither to reduce gray mold; on the tenth day after the flowers wither, 0.3% potassium dihydrogen phosphate, 0.01% boron calcium zinc and brassinolide are supplemented (brassinolide is determined by the commercial dilution multiple)

[0046] Example 5

[0047] After the four-year-old seedlings are planted, the crown width is required to be greater than 2 meters and the height is greater than 1.5 meters in the first three years based on the above seedling management. Starting from the fourth year, the whole garden is watered once on February 20. Fertilization and irrigation are stopped from the end of March to mid-April. Mancozeb is sprayed on the leaves once. The physiological differentiation of flower buds is completed in early June, and the young fruits enter the rapid expansion period. The weak trees are fertilized with N:P 2 O 5 :K 2 O=1:1:1 ammonium nitrate nitrogen fertilizer 150-200g / plant; from July to September, appropriate irrigation is carried out according to climate requirements. Pruning is carried out once after fruit picking in November. The tree shape is mainly pagoda-shaped. The large branches are cut and more small branches are left. 6-7 level branches are retained, and the angle between the branches and the vertical line is 45-55 degrees; after flowering, low nitrogen, high phosphorus and medium potassium water-soluble fertilizer is applied once, and fertilizer is supplemented according to the ratio of 0.8% of the amount of fruit picked, according to N:P 2 O 5 :K 2 O=1:3:2; Thinning branches during the flowering period in mid-November, with ventilation and light transmission as the main pruning during the flowering period. At the same time, select the flowers obtained 3-4 days after flowering and put them into water to wash out the pollen. The pollen is suspended with 3% brown sugar and 0.1% boron fertilizer. The collected pollen is diluted with 5% brown sugar and 0.1% boron fertilizer nutrient solution for liquid pollination. It can be pollinated manually or by drone, and pollination is carried out 1-2 times; in late November, drones are used to fly low-altitude to blow the flowers after the flowers wither to reduce gray mold; on the tenth day after the flowers wither, 0.3% potassium dihydrogen phosphate, 0.01% boron calcium zinc and brassinolide are supplemented (brassinolide is determined by the commercial dilution multiple)

[0048] Example 6

[0049] After the four-year-old seedlings are planted, the crown width is required to be greater than 2 meters and the height is greater than 1.5 meters in the first three years based on the above seedling management. Starting from the fourth year, the whole garden is watered once on February 20. Fertilization and irrigation are stopped from the end of March to mid-April. Mancozeb is sprayed on the leaves once. The physiological differentiation of flower buds is completed in early June, and the young fruits enter the rapid expansion period. The weak trees are fertilized with N:P 2 O 5 :K 2 O=1:1:1 ammonium nitrate nitrogen fertilizer 150-200g / plant; from July to September, appropriate irrigation is carried out according to climate requirements, and pruning is carried out once after fruit picking in November. The tree shape is mainly pagoda-shaped, and large branches are cut and more small branches are left. 6-7 level branches are retained, and the angle between the branches and the vertical line is 45-55 degrees; 20 days before flowering, low nitrogen, high phosphorus and medium potassium water-soluble fertilizer is applied once, and fertilizer is supplemented according to the ratio of 0.8% of the amount of fruit picked, according to N:P 2 O 5 :K 2 O = 1:3:2; thinning in mid-November during the flowering period, diluting with 2% brown sugar and 0.1% boron fertilizer nutrient solution for foliar fertilization; in late November, use drones to blow flowers at low altitude after the flowers wither to reduce gray mold; supplement 0.3% potassium dihydrogen phosphate, 0.01% boron calcium zinc, and brassinolide on the tenth day after the flowers wither (brassinolide is determined by the commercial dilution multiple)

[0050] The above embodiments weeded once at the end of June and the end of September, respectively, and the weeding was done manually.

[0051] Comparative Example 3

[0052] After the four-year-old seedlings are planted, the crown width is required to be greater than 2 meters and the height is greater than 1.5 meters in the first three years based on the above seedling management. From the fourth year onwards, the conventional traditional management method is followed: 500 grams of compound fertilizer + 10 kilograms of organic fertilizer are applied in the furrows every two winters, and then wait for the second year to repeat, without doing any other work to preserve flowers and fruits or flower bud differentiation;

[0053] Comparative Example 4

[0054] After the four-year-old seedlings are planted, the crown width is required to be greater than 2 meters and the height is greater than 1.5 meters in the first three years based on the above seedling management. From the fourth year onwards, the conventional traditional stocking method is adopted: that is, no more management is done, only picking work is done;

[0055] The weeding in the above cases was done manually, once at the end of June and once at the end of September.

[0056] Based on the above cases, 10 plants with consistent growth were selected for comparison in each case, and their average number of flowers, fruiting rate, average fruit weight, and single-plant yield were measured. Three years of data were taken. The fruit setting rate refers to the number of fruits retained on the branches at the end of March divided by the number of stigmas retained. See Table 2 for details.

[0057] Table 2

[0058]

[0059]

[0060] It can be seen from the above that the method of the present invention significantly increases the yield. It also shows that in the comparative example, if fertilizer is not applied according to the growth of the oil-tea tree, it will cause vigorous vegetative growth, which is not conducive to reproductive growth and flowering and fruiting.

Claims

1. A high-yield and high-efficiency cultivation method for oil-tea camellia, characterized in that: The following steps are involved: (1) Variety configuration: Select two or three varieties with the same flowering period, ploidy, and maturity period, and plant them in alternate rows; (2) Planting management: Select 3-4 year old seedlings, plant them in large holes, and place 15-30 kg of high-carbon organic fertilizer per plant; remove the seedling cups before planting, prune the roots, and plant in the rainy season after the beginning of winter. Prune after planting, leaving 2-3 branches in different directions at 20-30 cm; (3) Management of young trees: From the first to the third year after planting, when the new shoots mature in April-May and / or July-August, prune them every year to induce summer and late summer shoots to sprout. At the same time, add 50-100 g / plant of potassium nitrate compound fertilizer to the roots. (4) Management of mature trees: Starting from the fourth year after planting, stop pruning in spring and focus on winter pruning; (5) Preserving flowers and fruits: Ensure flower bud differentiation in April and preserve flowers and fruits in November, including garden cleaning, artificial pollination, shaking flowers to prevent gray mold, and fertilizing to preserve fruits.

2. The high-yield and high-efficiency cultivation method of camellia oleifera according to claim 1, characterized in that: The high-yield and high-efficiency oil-tea cultivation method is based on the climate of Hunan Province. The varieties in step (1) are two or three of Huaxin, Xianglin 210 or Huajin.

3. The high-yield and high-efficiency cultivation method of camellia oleifera according to claim 1, characterized in that: The large seedlings described in step (2) refer to seedlings that have grown for 3-5 years after grafting and have a ground diameter greater than 0.8 cm.

4. The high-yield and high-efficiency cultivation method of oil-tea camellia according to claim 1, characterized in that: The large-hole planting described in step (2) is specifically as follows: a 60*60*60 cm square hole is used, and a three-layer model of organic fertilizer, topsoil, and planting soil is used to improve the soil, wherein the organic fertilizer is a semi-mature plant-derived organic fertilizer.

5. The high-yield and high-efficiency cultivation method of camellia oleifera according to claim 1, characterized in that: The post-planting pruning in step (2) refers to selecting 2-3 branches with different directions, vigorous growth and an angle of less than 45 degrees with the vertical line at a distance of 20-30 cm immediately after planting.

6. The high-yield and high-efficiency cultivation method of oil-tea camellia according to claim 1, characterized in that: During the sapling management process in step (3), mancozeb and Metarhizium anisopliae should be sprayed in early March.

7. The high-yield and high-efficiency cultivation method of oil-tea camellia according to claim 1, characterized in that: The pruning described in step (3) is specifically to select three strong main branches facing outwards when the spring shoots mature in April and the summer shoots mature in June each year, and prune them by 1-2 nodes, leaving the outer buds.

8. The high-yield and high-efficiency cultivation method of camellia oleifera according to claim 1, characterized in that The winter pruning described in step (4) is specifically as follows: adopt the method of cutting large branches and leaving more small branches, mainly retaining 5-8 level branches, and more than 12 level branches.

9. The high-yield and high-efficiency cultivation method of oil-tea camellia according to claim 1, characterized in that: The fruit-preserving fertilization in step (5) is to apply fertilizer from 15 days before picking the fruit to 15 days before flowering, using a low-nitrogen, high-phosphorus, and medium-potassium compound fertilizer, and supplement fertilizer at a ratio of 0.5-1% of the amount of fruit picked.

10. The high-yield and high-efficiency cultivation method of oil-tea camellia according to claim 1, characterized in that: The flower and fruit preservation in step (5) refers to the management of the entire growth period from flower bud differentiation to pollination and fruit setting of the oil tea every year; watering the adult trees is strengthened at the end of February, and when the new shoots mature in April, water and fertilizer are controlled, and fertilizer is applied accurately according to the tree vigor to promote flower bud differentiation.

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