Key points of simple plastic film mulching technology for crown of early-maturing Satsuma mandarin

Key points of simple Film mulching Technology for the Crown of precocious Wenzhou Satsuma

Yiling District, Yichang City, Hubei Province is the hometown of precocious mandarin in China. At present, the cultivated area of citrus is 23300 hm2, and the annual output is more than 700,000 tons. As frosts often occur in the middle and late November of each year, 85% of the oranges are concentrated on the market from October to November, resulting in great sales pressure, and low prices often hurt farmers in high-yielding years. In order to avoid frost damage and prolong the supply cycle of precocious Wenzhou mandarin market, in 2010, the national modern citrus industrial technology system Yichang wide-skinned citrus comprehensive test station carried out a simple film mulching technology for the crown of precocious Wenzhou mandarin in Cangwu Village, Xiaoxita Street, Yiling District. Seven years' practice has proved that this technology can effectively reduce the abnormal fruit drop and rot of early-maturing Wenzhou mandarin fresh fruit, improve the fruit appearance and internal quality, prolong the supply period of fresh fruit for 3045 days, and increase the sales price by 0.400.60 yuan / kg. Generally covered with plastic film for about one and a half months, the net income can be increased by more than 1 000 yuan per 667 m2.

1 Technical key points

Preparation before film mulching. Select the polyethylene agricultural film with high light transmittance, which is generally required to have a thickness of 0.06 to 0.08 mm and a width of 4 to 8 m, and to prepare cloth strips, nylon ropes or braided ribbons, wooden stakes, etc.; to cut or retract the protruding branches at the top and periphery of the crown so as not to pierce the film and cut off the dead branches, disease and insect branches on the tree, together with ground weeds, litter and fruit, etc., concentrated burial or burning Within one week before plastic mulching, the canopy was sprayed evenly with avermectin 1500x solution + Dasheng Mmur4560000x solution + 2myryl D 30mg/kg, or Lvying 200x solution + prochloraz 500ml 1000fold solution + 24m D 30mg/kg, etc.

Time and method of film mulching. The main purpose of film mulching is to prevent the fruit from losing its economic value when it is frozen. Plastic film mulching is too early, the temperature has not dropped below 20 ℃, plastic film mulching is easy to burn leaves and fruits; too late, the fruit has been frozen and rotted. The suitable time for film mulching in Yiling District is before November 5. When a single plant is covered with film, a strip of cloth, nylon rope or braided belt is used to tie around the film and tighten it, and fix it with a wooden stake; when covering the film on both sides, the two ends of the film are fastened with a rope and fixed with a wooden stake, and a rope is pulled between the two trees along the vertical direction of the film to prevent the film from being overturned by the wind. For both coating methods, the gap between the edge of the film and the ground should be kept at a gap of 20 to 40 cm.

Management after film mulching. Strengthen daily inspection, pay special attention to film coverage after strong wind, rainfall and snow. The strong wind is easy to open or pierce the film, and if it is opened, blown or scratched after the strong wind, it should be repaired or fixed in time; rain and snow are easy to oppress or collapse to cover the film, and the water or snow on the film should be shaken off in time after rain and snow, and the damaged parts should be repaired in time. Prevent high temperatures. In a sunny day with high temperature, we should pay attention to timely opening the film and ventilation, so as to avoid sunburn. Remove the film in time. After all the fruits are harvested, the film should be removed from the canopy in time to facilitate tree restoration and reduce the impact on production in the coming year [Jishan Huayao].

2 points for attention

Garden choice. Selecting hilly or sloping land, the management level is higher, the tree is strong, and the damage of diseases and insect pests is lighter. The yield per 667m ~ 2 is carried out in the orchard of 3 000 ~ 5 000 kg, but it is not suitable to choose the sloping land and flat orange orchard.

Remove the fruit. The big fruit of early ripening Wenzhou mandarin is easy to float when harvested late. The fruits with transverse diameter greater than 65 mm can be harvested and sold, and the non-commercial fruits such as disease, pest, sunburn fruit and malformed fruit can be removed, and the tree load can be kept at about 2 mm.

Spray to protect the fruit. After plastic film mulching, the temperature and humidity in the crown rise, which is easy to aggravate the occurrence of red spiders and some diseases, and even cause abnormal fruit drop. Therefore, must be sprayed before plastic mulching to control red spiders, diseases and fruit protection of the combination of pollution-free chemicals, 2mai 4murD must be wet fruit pedicel.

Pick the fruit in time. After plastic film mulching, delayed harvest can improve fruit quality, but the harvest time is not as late as possible. If the pericarp is harvested too late, it is easy to float, which affects the fruit quality, is disadvantageous to postharvest transportation and storage, and is also disadvantageous to tree restoration [1]. According to the sales characteristics of precocious Wenzhou mandarin, the film mulching time in Yiling district is 40-60 days, and the early sale should be completed before the end of December, no later than the first ten days of January of the following year.