Citrus [scientific name] Citrus reticulata Rutaceae Citrus

【1】Control the growth of summer shoots

Paclobutrazol

Before summer shoots start to grow or when new shoots grow to within 3cm, 250-1000mg/L paclobutrazol liquid is sprayed 1-2 times on the foliage, which can shorten summer shoots by 50%-70% and increase fruit setting by 2%- 4%, the output is increased by 6% to 48%. In production and application, the concentration and frequency of use of different varieties are different: the best concentration of sugar orange is 300mg/L, the best concentration of Wenzhou mandarin is 750mg/L, the best concentration of ponkan is 1000mg/L, and the best concentration of local tangerine is 500mg/L /L, the range of orange usage is 250-750mg/L.

Fosamine-ammonium

When the summer shoots take up about 50% and the length is 1-1.5cm, spray the canopy with 750-1000mg/L liquid medicine. The number of summer shoots of Citrus decreased by 69, and the new shoots of orange citrus decreased by 43.7, and the lengths were 13.7cm and 13.3cm shorter than those of the control, respectively. The fruit setting rate was also significantly improved by spraying fosamine-ammonium. The spraying of 750mg/L of Citrus increased the most, which was 82.2% higher than that of the control.

Uniconazole

During the occurrence period of summer shoots, spraying the whole plant with 100-120mg/L dinoconazole solution can inhibit the shoot length of citrus saplings and promote fruit setting.

Meleic hydrazide

In order to delay citrus germination and avoid frost damage in early spring, spraying 800-1000mg/L Meleic hydrazide in late September can delay the spring germination of young citrus trees that have not yet produced fruit by 7 days, but it is not suitable for mature fruit trees.

Flumetralin

Spraying at the mature stage of spring shoots and the sprouting stage of summer shoots, when the length of new shoots is less than 7.5cm, use 125-250mg/L Flumetralin liquid spray for 2-3 times at intervals of 10 days, which can effectively inhibit the growth of new shoots. Promote fruit preservation, fruit expansion, and increase production.

【2】Protecting flowers and fruits, regulating fruit development

Sodium Nitrophenolate

Spraying 2.3-2.8mg/L liquid medicine once at the beginning of flowering, after fruit setting, and fruit expansion period can enhance the disease resistance of citrus, improve fruit setting rate, fruit expansion, increase sugar content, increase vitamin C content, and increase yield.

Diethyl aminoethyl hexanoate

Spray 8-15mg/L liquid once at the beginning of flowering, in the middle of physiological fruit drop, and when the transverse diameter of the fruit is 2 to 3 cm, which can accelerate the expansion rate of young fruit, improve the fruit setting rate, improve the disease resistance, and make the fruit surface smooth and thin. , sweet, early maturity, increased yield.

Brassinolide

Using 0.02-0.04mg/L brassinolide solution to spray once at the flower bud stage, young fruit stage and fruit expansion stage can significantly improve the fruit set rate of fruit trees, promote fruit expansion, increase yield, and have a good effect on later coloring. certain promotion.

Gibberellic acid

Spraying 25-50mg/L gibberellic acid liquid 7d after flowering and after the first early physiological fruit drop to before the second physiological fruit drop can promote the preservation of flowers and fruits. (Note: ① It can be mixed with cytokinin to improve the fruit retention rate of the first physiological fruit drop. ② The suitable period for the use of gibberellic acid in Wenzhou mandarin orange should be sprayed in advance from the end of full bloom to the time of withering. ③ When spraying , adding 0.2% urea, 0.2% potassium dihydrogen phosphate and 0.2% borax to the gibberellic acid solution can improve the effect of preserving flowers and fruits. ④ During the flowering and fruiting period, in high temperature and dry weather, the use of gibberellic acid should be combined with proper watering of the orchard. Combined to improve the effect of preserving flowers and fruits.)

Zeatin

During the flowering period and the late period of the first physiological fruit drop, evenly spraying with 0.002-0.003 mg/L liquid medicine has the effect of significantly increasing the fruit setting rate. In the fruit coloring stage, evenly spraying with 0.0015mg/L liquid can make the appearance of the fruit orange-red and the sugar content is high.

Triacontanol

Using 0.5-0.6mg/L triacontanol liquid for foliar spraying during the flowering period can not only improve the degree of coloration, but also increase the yield of citrus, improve the quality of citrus, and increase the sugar content of citrus.

DCPTA

Spraying 20-30mg/L DCPTA liquid evenly on the whole plant at the first flowering stage, after fruit setting and fruit expansion stage can achieve the effect of preserving flowers and fruits, improving fruit setting rate, uniform fruit size, good coloring and sweet taste, early maturity and increasing yield.

Forchlorfenuron

On 3-7 days after flowering and 25-35 days after flowering, 5mg/L Forchlorfenuron

solution combined with 25-50mg/L gibberellic acid for key fruit spraying treatment can increase the rate of melon setting and avoid physiological fruit drop.

6-BA

At the beginning of blooming (before the first physiological fruit drop), the young fruit stage (before the second physiological fruit drop) and before the fruit expands, spray 33.3 ~ 50mg/L6-BA liquid once each, focusing on the flowers and fruits, It can achieve the effect of promoting fruit setting and increasing yield, and can also be mixed with gibberellic acid for better effect. (Note: The shedding parts and physiological functions of citrus fruits at different developmental stages are different. For preventing the first early physiological fruit drop, 6-BA has a better fruit-preserving effect than gibberellic acid, while in preventing the second physiological fruit. When the fruit is dropped, the fruit retention rate of gibberellic acid is better than that of 6-BA.

Gibberellic acid (GA4+7) and brassinolide

Spray the whole plant with 2.5～5mg/L gibberellic acid (GA4+7) (compounded with 0.01～0.02mg/L brassinolide) at the early flowering stage or young fruit stage, focusing on the flower and fruit parts, which can play a strong role in blooming , The effect of protecting the fruit.

【3】Reduce fallen leaves, resize years

6-BA

Spraying 33.3-50mg/L6-BA at the end of the flowering period of the young orange tree can significantly improve the fruit setting rate and increase the yield of the young orange tree.

Gibberellic acid

Spraying 100mg/L gibberellic acid in November (sweet orange) or mid-January (Wenzhou mandarin orange) during the flower bud differentiation period of the young orange tree can reduce the number of flower buds and avoid excessive fruiting in the next year.

Paclobutrazol

Spray 1000mg/L paclobutrazol once on the canopy of ponzu from August to late September, which can promote germination and differentiation, increase the number of flowers in the next year, and greatly increase the yield, thereby reducing the range of fruit in the size of the orange tree.

Ethychlozate

For Wenzhou mandarin oranges and local early varieties, spray 100-200 mg/L ethychlozate on the crown 30-40 days after the flowering of the big year orange tree, which can thin out the smaller and young fruits in the crown, so as to avoid too many fruits in the current year, and the effect is basically Equivalent to artificial fruit thinning.

【4】 Application of other regulators on citrus

Propyl Dihydrojasmonate and Gibberellic Acid

45d before harvest, spraying with 25mg/L propyl dihydrojasmonate and 1-3.3mg/L gibberellic acid can effectively prevent the occurrence of “floating skin” of citrus.

2,4-D and gibberellic acid

Before coloring, spray the fruit with 8～12mg/L 2,4-D liquid and 5～15mg/L gibberellic acid, which can achieve a good effect of fruit hanging and fresh-keeping.

Chitosan

After the citrus was harvested, 2% chitosan liquid was evenly sprayed on the fruit surface and dried, and no obvious spots appeared after being stored at 30°C for 7 days.

Prochloraz

After harvesting when the citrus is ripe, select the uninjured fruit, use 250～500mg/L prochloraz solution, or 180～225mg/L prochloraz with 4～5mg/L chitosan solution, or 150 mg/L chitosan solution. ～200mg/L Prochloraz combined with 25～33mg/L Imazalil liquid for 1～2min, pick it up and dry it for storage, it can prevent pedicle rot, anthracnose and mildew, and increase the storability.