Maize hybrid production technology
1 Reasonable sowing 1.1 Timely early sowing, film-covered warming Some late-maturing varieties have a long maternal growth period. After pollination, the temperature in the middle and late stages of filling begins to fall, and the accumulated temperature required for normal maturation cannot be met, resulting in poor maturity and seed germination. The rate is low. For these varieties, timely sowing and timely heating of the cover film will be adopted, and water and fertilizer management will be strengthened in the middle and later stages to ensure the healthy growth of the plants. This measure not only satisfies the accumulated temperature required by these varieties, but also matures earlier than open field seed production. 1.2 reasonably determine the density of the planting density is too small, low seed production; density is too large, due to water, fertilizer, light and other factors, resulting in the grain is not full, the germination rate will not go. Therefore, a reasonable planting density should be determined. 1.3 Reasonable period of error to ensure that the flowering period meets at the time of planting so as to ensure a reasonable period of error, so that the flowering period meets. In case of no meeting, the principle of “Ningke and other fathers, and not the father and other mothers†should be followed, that is to say, the mother would rather leave 2 ~ 3d, but the father of loose powder 2 ~ 3d can not be. 2 Do a good job in field management 2.1 Timely seedlings, Dingmiao in the plant 5 to 6 leaves when the Dingmiao, between the weak seedlings and hybrid seedlings, try to keep the mother size uniform growth, the father left size seedlings (pull on the basis of hybrid seedlings) In order to prolong the loose powder period, it will facilitate pollination. 2.2 timely watering, fertilization, disease prevention, pest control, weeding, weeding, ensure robust growth of seed, ensure seed maturity and grain growth, to prevent the growth of plants due to water, fertilizer, disease and other reasons, affecting the germination rate of the seed . In addition, timely application of fertilizers and preventing the lodging of corn was performed after the application of panicle fertilizer. 3 Strictly go to miscellaneous and mischief. The first time before sowing, seeds with inconsistent grain type and grain color were removed. The second time can be combined with Dingmiao, according to the leaf shape, leaf color and stem base color and seedling growth, will not meet the typical characteristics of the hybrid seedlings removed at the same time, combined with the inferior, the unqualified disease seedlings removed. The third time in the jointing stage, due to mixed growth plants with superior growth, the plants were significantly taller than the parent plants, and the leaf color and leaf shape were also significantly different. All the plants that did not meet the typical traits were removed, and the poor and diseased plants were also removed. . The fourth time before tasselling, the hybrid plants were identified based on the plant growth, plant type, leaf color, leaf shape, leaf width, and filament color, and all the plants that did not meet the typical characteristics were removed. After harvesting on the fifth time, in the field, spikelets, grain types, grain color, cob color, and other characteristics were used to remove spikelets and spikelets that were inconsistent with the standard spikes. 4 Timely and thorough detoxification is the key to ensuring the purity of seed. It is necessary to organize well the manpower, master the timing of emasculation, pull it out once a day, and it is timely and thorough. We asked for the promotion of tying with one or two parietal lobes. The tassels pulled out were concentrated and brought out to the ground. This will not only ensure the quality of emasculation, but also promptly remove the growth center where the top consumes more nutrients and ensure that the ear has more nutrients. At the same time, it can also stimulate the mother to advance spinning 2-3d to promote early maturing. In short, the general principle of emasculation is: males and females do not meet each other, the field is not blind, and the three types of seedlings are not seen. 5 When the paternal parental pollination is finished, the parent must be removed promptly and thoroughly. This can save water and fertilizer, reduce the inefficient consumption of nutrients, and promote the mother's complete absorption. At the same time full of light, good ventilation, help prevent disease and promote maternity ear premature. And prevent the mixing during harvest, thus ensuring the seed purity and germination rate. 6 Accelerate dehydration in time There are three methods commonly used for dehydration: 6.1 Drying the field skins 6.1.1 Drying the standing culm skin When the parent ear enters the wax ripening stage, it can even be peeled off during the emulsification period. To peel off in the end, can not stay above the grains, in order to prevent the accumulation of water at the base of the ear, so that the grains have mildew. 6.1.2 Drying of stalk stalks The methods and requirements for stripping stalks are the same as those for standing stalk stalks. The difference lies in that when the loquat leaves are peeled off, the stem on the ear position is twisted and bent to the underside of the ear, so that the ear of the loquat leaves is planted on the top of the plant to promote dehydration faster. 6.1.3 Early harvesting combined with sorghum drying and early harvesting is the harvest at the latest when the grains begin to harden at the end of wax ripening. Since the source of moisture is cut off after harvesting, the dehydration process is shortened. The method of drying the sorghum is to cut off the upper part of the corn stalk while harvesting, and then peel off the outer leaves of the ear to leave 3 to 4 pieces of stalks inside and leaves 2 to 3 pieces of the ear respectively. The leaves are tied together and hung on the gills and rotated once every 2 to 3 days until they reach the standard moisture. 6.2 After the harvested seeds are harvested and transported, they can be air-dried by the “four-up†method, ie, drying on the shelves, the upper house, the upper wall, and the upper tree. In addition, it is also possible to use a large space yard for flat drying, requiring that it be turned twice a day and must not be loaded, bagged, or stored for a long time. 6.3 In artificially drying low-temperature years, natural precipitation with slow-maturing and slow-drying hybrid combinations is difficult, and mechanical drying can be used. High-moisture seeds should be intermittently dried using multiple intermittent drying. Once precipitation is too much, the seeds are heated for a long time and the temperature is too high, which affects the seed germination rate. 7 Securing, harvesting, seed harvesting, threshing, and selective processing are the last steps to ensure seed quality. In the acquisition process, households should be removed before threshing, removing spikelets and self-crossing ears, and concentrated threshing. In the threshing and selection processing, it is necessary to ensure that the site and machinery are clean and prevent artificial mixing.