Four seasons of grapefruit is produced in Zhejiang, Guangxi, Guangzhou and other places, the four seasons of flowering, the fruit of the four seasons is called the four seasons of grapefruit. The market value of the four seasons of grapefruit is very high, and there are fruits in all seasons, so the management of it is more cumbersome than other grapefruit, and I will introduce it to you one by one.
1. Regulate the amount of flowering and fruit set
From late March to mid-April, the flowers are sparsely flowered, and 1 to 2 leafy inflorescences are retained, and all leafless inflorescences are removed. Fruit thinning is carried out from mid-June to early July, at which time the amount of fruit set in the tree body is basically determined. The degree of fruit thinning depends on the tree potential and the fruit load of the tree body, first remove the deformed fruit, the fruit on the weak fruit branch, and then remove the fruit with too much local hanging fruit, through multiple fruit thinning, so that the fruit set part of the tree body remains relatively uniform.
2. Control the summer shoots to protect the fruit
The contradiction between the adult treetops of the four seasons of grapefruit is prominent, often due to the strong hair of the summer shoots caused by serious fruit drops, resulting in a reduction in yield, so in mid-May or late May, the summer shoots need to be completely erased by hand.
3. Plant growth regulator and extra-root topdressing to preserve fruit
Most of the old leaves of the four-season teak tree fall off when the new leaves are formed, coupled with the rainy weather during the flowering period, so the nutrient supply of the tree is often insufficient, so the application of fruit preservatives and extra-root fertilization and fruit preservation is an important auxiliary measure that cannot be ignored, the first fruit preservation in early May (2/3 of the flower), and then every 7 to 10 days, a total of 3 times. With Ketran No. 1 60mg/kg, foliar po 100mg/kg, potassium dihydrogen phosphate 0.2% + urea 0.4%. Or you can use citrus fruit preservative 50g, "nine two 0" 1g, urea 150g, potassium dihydrogen phosphate 100g plus water 50kg fruit preservation.
4. Circumcision to preserve the fruit
For trees with less flowers, cut the main branch or the long branch in a circle with an electric knife as early as the beginning of flowering, and the depth is only to cut the cortex, and circumcise the flowers.
5. Timely drainage and irrigation
In the rainy weather during the flowering period and young fruit stage of the four seasons of grapefruit, it is necessary to pay attention to the drainage of water, if the field is long-term accumulation of water, resulting in serious fruit fall of grapefruit in all seasons. May to June fruit fall period, at the turn of spring and summer, the temperature changes greatly, in case of drought for more than 7 consecutive days, the weather is sweltering, it will seriously fall fruit, to timely irrigation. In case of heavy rain or heavy rain, the accumulated water should be removed in time, and the soil should be moderately relaxed and cultivated after the rain.
6. Pest control
Bud maggots
When the buds begin to turn from green to white, 5 to 7 days before the adult feathering is unearthed, 1.25 kg of diazin farmers and 15 kg of fine soil are evenly mixed on the tree disc and the ground beyond 15 cm around the tree disc to prevent the adult worm from emerging, and the canopy spray can also be carried out with 90% enemy insect 800 times liquid and 2.5% cypermethrin 2500 times liquid to kill the excavated adult insects, and at the same time, remove the affected flower buds in time.
Anthrax, scabs
Spray once a drug in 1 to 2 cm of spring shoots and 2/3 of the time of Xie Hua to protect the young fruits of spring shoots, and can use 0.3% to 0.5% Bordeaux liquid, 50% antibacterial special wettable powder 500 times liquid, 50% tolbuzin wettable powder 600 to 800 times liquid, 65% daisen zinc 600 times liquid.
Red spiders, rusty ticks
Use 10% Liuyangmycin 1000 ~ 2000 times liquid, 95% oil emulsion 150 ~ 200 times liquid, 15% pyridoxine emulsion 1500 ~ 2000 times liquid or 50% bromo mite ester emulsion 1000 ~ 3000 times liquid prevention and control.
The original authors are Zhou Renyi, Shen Shirong, Pan Xiaoqiang