Lemon is warm, resistant to shade, not cold, and also afraid of heat. Therefore, they are suitable for annual average temperature 17 ~ 19℃, greater than or equal to 10℃, annual effective accumulated temperature of 5200 ~ 6500℃, monthly average temperature 1℃ and extreme low temperature of 6 ~ 8℃.
In the area where the annual average temperature is lower than 17℃, the area where the short-term low temperature is -5℃ and the periodic freezing injury, it is not suitable for economic planting in the open field.
The requirements for soil and topography are not strict. Flat land and hilly slope are suitable for planting, but the slightly acidic soil with deep and loose soil layer, rich organic matter, strong water and fertility conservation, good drainage, low groundwater level and pH value of 5.5 ~ 6.5 is the best.
1, lemon distribution range
Lemon is native to Malaysia, distributed in the United States, Italy, France, Mediterranean coast, Southeast Asia and America, and also cultivated in China, Taiwan Province Province, Fujian, Guangdong and Guangxi.
2, lemon pest control
Lemons have strong resistance to pests and diseases, especially in the north, where the climate is dry and there are few pests and diseases. Mainly prevent pests and diseases, and pay attention to cleanliness and hygiene in cultivation management. There is dust on the leaves, so it should be washed with water. Ventilation and light transmission are also important.
disease
There are mainly anthrax, scab, gummosis, foot rot, macular disease, brown spot and so on. The main control methods are: strengthening cultivation management, paying attention to irrigation and drainage, applying more organic fertilizer and pruning in time to avoid orchard closure. The prevention and treatment of gummosis and hoof rot is to cut off the affected part first, and then apply lead-copper or ethyl aluminum phosphate solution to the affected part for 7- 10 days, 1 time. Other diseases are mainly sprayed 1 time from April to September (it can be mixed with other pesticide abuse). When you are sick, you can add fresh life or new life.
insect pest
mite
Artificial release of predatory mites, interplanting agastaches in orchards, etc. Attention should be paid to using Bordeaux mixture or stone sulfur mixture and broad-spectrum bactericide as little as possible to avoid killing natural enemies. Spraying 0.5% fruit juice for 500 times, a total of 1 time, from fruit picking to spring shoot germination in the following year to eliminate overwintering eggs and treat other pests and diseases. When the spring shoots are about 2 cm long and the tender leaves stretch, the time is about the end of March, and the annual leaves of lemon are investigated 65,438+0 times every 7-65,438+00 days. When the number of mite eggs reaches 200/65,438+000 leaves, or when the number of mites reaches 50%, it should be sprayed in time, and the number of mites reaches 600/ hour after flowering. The pesticide should be 0.5 Victoria 2000 times solution, 5% Nisolone 2000 times solution, 15% etofenprox 2000 times solution, red mite 3000 times solution, acaricide 1000- 1500 times solution, etc. When the average density of rust mites reaches 2-3 heads/field of view in summer and autumn (hand-held magnifying glass 10 times), or when a few black fruits are found in individual trees and rusty brown leaves appear in individual branches and leaves, spray engraving should be carried out.
Bud maggot
According to the prediction of pests and diseases, it is necessary to use the favorable opportunity of spraying drugs when the adults don't fly immediately when they are unearthed, or when they sprout (as white as mung beans), or when they just sprout and the adults are about to emerge. 25% carbaryl powder 1.5 kg or 2.5% trichlorfon powder 1.5 kg can be selected per mu, and 30-35 kg of fine loess can be mixed. You can also choose 2.5% triadimefon 2000-2500 times or 20% pyrethroid 3000-4000 times for ground spraying, 7 7- 10/day 1 time, and spray it twice continuously.
scale insect
If the pesticide is applied 2-3 times during the incubation period, 70% Amilol 6000- 10000 times, or 3% Meuron 2000-2500 times, Mick 1000- 1500 times and 48% Loben 65438 can be selected. Cut off dead branches, dead branches and closed branches.
Whitefly
Combined with pruning in winter, the dense and weak branches, sprouting branches and insect branches are cut off to improve ventilation and light transmission conditions. Reduce the population base of overwintering insects. 1-2 instar nymphae should be controlled by pesticides in the peak period. For the types and concentrations of pesticides, see scale insects. Protect and utilize natural enemies. The natural enemies of whitefly pests include parasitic bacteria, parasitic bees and predatory natural enemies. Pay attention to the selection of chemicals that do little harm to beneficial organisms when controlling pests and diseases.
swallowtail
When the number of larvae is small, the eggs can be taken out and the larvae can be killed. When the larvae occur for a long time, they should be sprayed at the peak of 2-3 instars. The medicine can be 2000 times that of 20% pyrethroid killing solution, or 3000-4000 times that of 2.5% kungfu solution.
Leaf miner
It is mainly to erase sporadic early-onset and irregular summer shoots and put them together to reduce the population base. When it is found that the damage rate of new buds reaches 5% when new buds are pulled out, or the egg (worm) rate of new buds reaches 30% after new buds are released, spraying drugs is started. Spraying continuously for 2-3 times every 7- 10 days, 1 time. The medicament can be 7% Amirault 1000- 1500 times, 0.5% trifluoroether 800 times, 2.5% gongfu 2000-3000 times, 20% isocarbophos EC 800 times, etc.
Reference link: Lemon (Rutaceae Citrus) _ Baidu Encyclopedia