Main Producing Areas of Mandarin Oranges and Key Points of Cultivation and Management Techniques

China is one of the places of origin of citrus in the world, with numerous famous, special and high-quality citrus brands, so where are mandarin oranges produced? How are they cultivated and managed?

1. Where are mandarin oranges produced?

At present, 104 citrus products across the country have obtained origin protection or geographical indication status, mainly concentrated in Guangxi, Guangdong, Hunan, Hubei, Jiangxi, Sichuan, Chongqing, Fujian, Zhejiang, Hainan, Yunnan, Guizhou, Shaanxi and other areas.

Take Hunan and Guangdong as examples. Hunan citrus varieties are mostly honey mandarins and oranges, and the more influential ones include Dongjiang Lake Honey Mandarin, Yongxing Bingtang Orange, Daozhou Navel Orange, Xiangxi Ponkan, Yizhang Navel Orange, Mayang Bingtang Orange, etc.

Among Guangdong citrus varieties, geographical indication products with good development momentum at present include Meizhou Golden Pomelo, Xinhui Mandarin, Xinhui Chenpi, Lianjiang Red Orange, etc.

2. How are mandarin orange trees cultivated and managed?

1. Soil management

Soil is the unconsolidated layer on the land surface composed of minerals, organic matter, water, air and organisms, with fertility and capable of growing plants.

Citrus grows well in light soils, but if a suitable rootstock is used and there are good drainage conditions, citrus can also grow in heavy loam. Soil with a pH above 8.0 is unfavorable for citrus growth. Citrus is sensitive to soil salinity and boron (even in deep soil), and is also sensitive to compacted soil.

Citrus roots are mainly distributed in the 0.90 m soil layer and vary depending on irrigation conditions. The vast majority of aerobic active roots are distributed in the surface 30 cm soil layer. In light soils, the recommended irrigation cycle is 2 times per week, and daily irrigation is even better.

Obviously, because water in light soils easily permeates below the active root zone, frequent and small amounts of irrigation will produce better results.

2. Fertilizer and water management

Citrus needs irrigation in dry months, so when winter is dry and the temperature is above 13°C, irrigation must be carried out. In addition, dehydration is dangerous, as it causes fruit moisture to flow to the leaves and causes the fruit to shrivel. In the past, irrigation mainly used furrow irrigation or overhead sprinkler irrigation above the canopy, but sprinkler irrigation carries a risk of salinization, and furrow irrigation can cause decreased soil aeration.

Now there is a tendency to use drip irrigation and micro-sprinkler irrigation under the canopy, irrigating in bands, with part of the soil surface kept dry.

For orchards where phosphorus and potassium fertilizers were not fully applied before planting, the application of phosphorus and potassium fertilizers should be increased year by year; one month after young trees are planted, new roots begin to become active, and diluted manure water can be applied. The amount of fertilizer should be small rather than large, and dilute rather than concentrated, especially chemical fertilizers, where even more attention should be paid during application to avoid damaging the roots.

3. Pest and disease management

The most serious damaging ones mainly include:

(1) Citrus blossom midge: when the flower buds show white, spray with 80% dichlorvos emulsifiable concentrate at 1000 times dilution + 90% crystalline trichlorfon at 800 times dilution, which can also control aphids at the same time.

(2) Mites (red, yellow and white spiders): spray with 40% Yinman emulsifiable concentrate at 1500-2000 times dilution; spray with 34% Saomanite emulsifiable concentrate at 1000-1500 times dilution. The above three acaricides should be used alternately or mixed.

(3) Scale insects: at the early stage of hatching, namely late April and mid-May, spray with 40% Supujie emulsifiable concentrate at 1500-2000 times dilution, which can control arrowhead scale, red wax scale, black scale, cottony cushion scale, etc.

(4) Aphids and whiteflies: spray with acetamiprid or imidacloprid preparations at 1000-2000 times dilution.

(5) Leafminer: deltamethrin, Kung Fu emulsifiable concentrate and other pesticides can be evenly sprayed when new shoot leaves grow to 1-1.5 cm; for swallowtail butterflies, manual killing of eggs or small silkworm-like larvae on tender buds and tender leaves can be used, and yellow sticky boards can also be used to trap and kill adults, or pesticides such as Mieshaoli and trichlorfon can be used for control. Under normal circumstances, fungicides and insecticides can be mixed (alkaline pesticides should be used alone), which can both improve efficacy and reduce labor intensity.