1, choose suitable regeneration species. According to the author's many years of experimental observations, most of the early and middle-maturing hybrids that are promoted at present can be cultivated for regeneration. Spring, Black Beauty, Japan Sweet Jane, and Xiongnong 8 are most suitable. In short, cutting vines to reproduce cultivars, should be high quality, high yield, disease resistance, stem vine regeneration ability and other comprehensive traits good varieties. 2, determine the best sowing date of spring melon. In order to promote better growth and development of watermelons, spring cucumber sowing should be advanced as soon as possible, generally in mid-and late March sowing nursery, seedling age 25-30 days, planting in mid-April, and implement plastic film cover cultivation. Where conditions permit spring-sowing watermelon can be covered with double membranes or greenhouse cultivation, it is more advantageous for the high yield of regenerated watermelon. 3, increase spring preharvest fertilizer. In order to promote the development of spring watermelon root system, vigorous vitality, maintain vine leaves enduring, and powerful new hair, 1 week before spring harvest watermelon harvesting available nitrogen fertilizer, usually 15-20 kg urea per acre, and All vines are topping. According to the experiment, fertilization was carried out on the 7th day before cutting vines, on the 2nd day after vine cutting, and on the 7th day after vine cutting. The result is that: different fertilization periods have a great influence on the yield of regenerated melon. Fertilizer is applied on the 7th day before vines are cultivated, and 738 kg of melons are produced per acre. On the 2 nd day after cutting vines, 691 kg of melons are produced per acre; On the seventh day of fertilization, 439 kilograms per mu were produced, and the former yield was significantly higher than the latter two. 4, cutting time and methods. In order to create conditions for the early reaping of the regenerate melons, we should pay attention to strengthening the management of spring sowing watermelons, and strive to make their 2nd and 3rd female flowers sit in order to ensure that the harvest period is relatively consistent. When all the melons have been harvested, they can be harvested in a timely manner, and do not wait for the ripening of individual high-potential melons. The method of cutting vines is to keep 10-15 cm vines at the base of the main vines and side vines, and the rest are cut with a knife. The knife must be sharp, and the incision must be smooth, and it must not be brushed and fluffed. The cut stems, together with fallen leaves and weeds, should be cleared out of the garden in time. In order to reduce the risk of infection, cutting vines must be done after sunny dew. Pay attention to not stay too long, because the high-node axillary bud germination is slow, the new vine thin and weak, and the axillary buds germinate quickly at the base, the new vines are scattered and strong, easy to sit melon, knot big melon. One Step SARS-CoV2(COVID-19) IgG/IgM Test IgG and lgM antibodies to 2019 Novel Coronavirus can be detected with 2-3 weeks One Step SARS-CoV2(COVID-19) IgG/IgM Test Kit NINGBO AUTRENDS INTERNATIONAL TRADE CO., LTD , https://www.metests.com
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