Qingmao Leaf Chinese Cabbage is a type of Chinese cabbage native to the coastal area of ​​Tianjin, which was selected and cultivated by local farmers for several hundred years. Due to the fact that it is located at the intersection of marine and continental climates, the climate is variable and the soil salinity is high. Therefore, the varieties bred under this condition have strong adaptability to adverse climatic conditions and soil conditions, forming resistance and The characteristics of strong disease resistance, especially the resistance to dry heart disease are abnormally prominent; from the appearance point of view, the leaves of the Chinese cabbage leaves of Qingmao leaf are wrinkled in a walnut pattern, the photosynthetic area is enlarged, and the leaf color is dark green and chlorophyll content. High, increased photosynthetic efficiency, the ball rim is emerald and helps thin, leaf ball appearance, good merchandise. The Tianjin Kerun Vegetable Research Institute has carried out special research on Qingmao leaf and Chinese cabbage since the 1970s, and has successively developed "Jinqing series", "Autumn green series", "Jinbai series" and "Jinbai series" of different sizes of young leaves. More than 10 hybrid generations, such as the Jinqiu series, are more resistant to diseases and more ballistic than conventional conventional ones, have better product consistency and commercial quality, and have higher yields, but have been affected by greenhouses in recent years. As a result of the effects, the global temperature has been increasing year by year, and the warm winter has become more and more frequent, which has had a great impact on the production of Chinese cabbage in autumn, especially the determination of suitable sowing dates.In the face of the new situation, new cultivation techniques must be adopted: First, choose the appropriate variety The varieties suitable for autumn sowing in straight-barreled young leaves include the Qiu 78, Jinqiu 1, Qiulv 75 and Qiulv 80 with growth periods of 75-80 days, and the autumn green 60 and autumn green with the growing period of 55-65 days. 55. Tsukikura 65, Tsukihachi 606 and Tsubasa 56 and Tsugaru 45 with a fertility period of about 45 days. The specific selection of which variety depends on the purpose of the grower. If a large vegetable or a winter storage dish or a transported vegetable is needed, a variety with a growth period of 75 to 80 days can be used; if a small vegetable, a morning market, or a fore crop is needed Late, late evening, late growth period, etc. can choose the reproductive period of 55 to 65 days or about 45 days of the species; if you need to help white dishes can be selected Jin Bai 56 and Tianjin White 45. Second, select the appropriate sowing time The temperature requirement for the whole growing period of autumn sowing Chinese cabbage is gradually decreasing from high to low. The higher temperature at the early stage (about 25°C per day) is conducive to germination, emergence and strong seedlings. The slight decrease in temperature during the rosette period (about 20°C per day) is beneficial to the formation of rosette leaves (functional leaves). The need for cooler temperatures, but also requires a certain temperature difference between day and night (daytime 20 °C ~ 23 °C, night 10 °C ~ 15 °C), is conducive to leaf ball expansion and compaction. Therefore, proper sowing is an important part of autumn sowing cabbage. Premature sowing, a long time in the high temperature period is not conducive to the ball, easy to appear deformed, scattered trees, the wrong heart and other phenomena, in addition, the high temperature can easily lead to serious pests and diseases, affecting yield and quality; too late sowing due to accumulated temperature is not enough, The growth rate is too slow to form a normal ball. The principle of determining the appropriate sowing date includes two aspects, one is the characteristics of the selected species and the other is the purpose of planting. For the characteristics of varieties, the growth period of the selected species is mainly considered. The varieties with long growth stages have strict requirements for the sowing date. For example, it is 75-80 days of Jinqiu 78. It is advisable to sow on August 12-15, which is based on The purpose of planting is to determine the specific planting date. If fresh vegetables are to be marketed or brought to the market for early sowing, if they are to be stored and then put on the market, they can be sowed in an appropriate manner to reduce disease and facilitate storage. Variety of suitable short-growing period of sowing a wide range of fields, such as 60 days of autumn green 60 in August 8 to 25 can be planted in this range and then determine the specific sowing date according to the purpose of planting, if in order to be listed on the National Day It can be planted on August 8th. If you want to go to the market at night, go to market, reduce the disease, and use less pesticide to sow late; if you want to use it as a big vegetable and store it, you can sow it before and after August 14th. Gain more harvest because the suitable harvest period of Qiu Lu 60 is longer, that is, it matures when it grows to 60 days or so, and it can be harvested. If it is not collected, the leaf ball can continue to grow, and the yield is higher. Third, the election and preparation The selected land should be selected to contain more organic matter and fertile soil, and it is necessary to keep water strong and to facilitate drainage. The key is not to link crops with cruciferous vegetables to reduce the invasion of diseases and insect pests. Before the site preparation, adequate base fertilizer should be applied, especially for planting medium and late-maturing varieties with large trees. The growth period is longer and the amount of fertilizer required is large. Attention should be paid to the application of base fertilizer. In general, good quality manure or compost 3000 to 4000 kg and superphosphate 300 kg can be used per acre, and the two can be mixed and used as a base fertilizer and applied to the soil. In some areas along the coast of Tianjin and Hebei, due to the high saline-alkali content in the soil, it should be cultivated in flat hoe. In non-alkaline areas, small high ridges can be planted on top of high ridges to facilitate drainage and prevent soft rot. Fourth, sowing The sowing methods of different varieties are basically the same. The live broadcast method is used in most of the autumn sowing seasons, because the live broadcasting method is simple and easy to grasp, and labor and labor are saved. The live broadcast is divided into seed drilling and hole sowing. Compared with the seedlings, sowing seedlings can save seeds, and the workload of seedlings and plantings during seedlings is reduced. However, special attention must be paid when sowing seedlings. Therefore, in the case of adequate seeds, most of the drill method. V. Saplings and trees Generally sowing seedlings after sowing, the seedlings are more dense, small seedlings are too dense, crowded easily lead to leggy, so that the seedlings are weak, affecting the normal growth in the later period, which affects the yield, and therefore time and seedlings and fixed trees. Usually in the pull cross period and 4 to 5 true leaves during the seedlings 2 times, set in the 7 to 8 leaf period, plant spacing varies from species to species, late mature trees about 40 cm, early-maturing small trees about 33 cm. When setting trees, extra attention should be paid to removing weak seedlings, diseased seedlings and hybrid seedlings. In the absence of seedlings and ridges, seedlings should be promptly filled. After the trees were established, weeding and weeding were carried out immediately. Sixth, fertilizer and water management 1. Fertilization. The fast-growing fertilizer in the rosette stage ensures the rapid growth of functional leaves, mainly urea, ammonium sulfate or diammonium phosphate, with an application rate of 15 to 20 kg/mu; the quick-improving fertilizer can be used to ensure the rapid growth of leaf bulbs during the ball-forming period. Demand, respectively, in the early stage of the ball and the middle of the ball, respectively, topdressing nitrogen fertilizer (urea or ammonium sulfate), the amount of 20 kg / acre, each time after fertilization should be timely watering. 2. Watering. Sewage water before sowing to ensure the emergence of seedlings and seedlings need to grow; seedlings should be little water pouring to ensure that the micro-climate environment conducive to the cultivation of strong seedlings; lotus seedlings appropriate to promote the roots to the depth of development; watering season should be sufficient In order to ensure the rapid growth of the leaf ball; for the winter storage dish to stop watering 7-8 days before harvest. VII. Pest Control The main diseases of Chinese cabbage in Jin and Shu area include downy mildew, soft rot, viral disease and brown rot. The main pests include roundworm, cabbage caterpillar, and diamondback moth. Chinese cabbage leaf type cabbages all have strong resistance to disease. If appropriate late sowing is adopted to avoid disease cultivation, and strong water and water management are used to cultivate strong seedlings and strong trees, the occurrence of diseases is extremely light or even non-pathogenic, so the appropriate sowing date is selected. And to strengthen the cultivation and management of each growth stage is the key to disease prevention; besides, observing the appearance of fields at any time, discovering the conditions and pests timely treatment, and eradicating the diseases and insect pests in the bud, can minimize the damage of pests and diseases, and at the same time reduce The amount of pesticides reduces production costs.
