Summer corn flower grain management technology

The flowering stage refers to the stage from the tasseling to the maturity of corn. In this period, the vegetative growth is basically over, and the vegetative growth and reproductive growth at the ear stage progress to the stage of reproductive growth centered on flowering loose powder and fertilization, which is a key period for forming yield, determining the number of kernels and grain weight. The main target of this period of management is to raise roots and protect leaves, prevent premature aging and greed, prolong the functional period of green leaves, prevent grain abortion, and increase seed setting rate and grain weight. The main technical measures for field management are:

　　 1. Follow the "attacking fertilizer" as appropriate. The high-yield practice has proved that the corn leaf area is large, the photosynthetic efficiency is high, and the leaf function period is long, which is the basic guarantee for achieving high yield. One of the important guarantees for the ripening of corn stalks is the sufficient inorganic nutrients in the flowering stage. Therefore, the attacking fertilizer should be pursued as appropriate. The so-called discretionary application depends on the appearance of the plants in the field. In the field where the panicle fertilizer is sufficient, the plant looks good, the leaves are dark green, and there is no early decline, the field may not be applied to avoid prolonging the growth period; If the plant is defeated, it should be supplemented with granular fertilizer. The attacking fertilizer is generally applied before and after the flowering stage of the ear, combined with watering, applying 5 kg of urea or 10 to 15 kg of ammonium bicarbonate . The high-yielding summer maize requires a large amount of fertilizer in the late growth stage, and the plot that lacks fertilizer during the filling stage can also be quickly replenished by foliar topdressing. During filling with 1% to 2% urea solution, 3% to 5% of the leach solution or superphosphate 0.1% to 0.2% potassium dihydrogen phosphate solution spraying, extended function of leaves, increased thousand kernel weight 7 More than % .

　　 2. Go to the male in time. De-male can reduce nutrient consumption, promote nutrient transport to the ear, increase light intensity, increase light energy utilization, reduce plant height, and enhance lodging resistance. At the same time, the male can also bring some corn borers and aphids out of the field. Reduce damage, promote grain development, increase kernel number and grain weight, and generally increase yield by about 10 %. The emasculation is carried out before the tassel has just been withdrawn without loosening the powder. It is easy to bring out the leaves too early to reduce the photosynthetic area. The tassels have already bloomed loose powder and reduced the emasculation effect. Going to the male to go to the male or the male to the male, the number of male plants does not exceed half of the total number of plants, the ground does not go to the male, even the rainy days and high temperature and dry weather do not go to the male, in order to prevent pollen deficiency affect pollination and cause thin The grain is bald.

　　 3. Artificial assisted pollination. Artificial assisted pollination can ensure normal pollination and fertilization, improve seed setting rate, reduce baldness and promote grain uniformity. Auxiliary pollination is more effective for plants with late silking and for larger and weaker plots. Artificial pollination is generally carried out at the end of the flowering period. It is selected from 9 to 11 am on a sunny day . The powder is collected and pollinated continuously for 2 to 3 times. It is necessary to pay attention to the pollination of different plants.

　　 4. Watering and draining in time. The corn flower grain stage is the critical period of water demand. In this period, the water consumption of corn accounts for about 50 % of the total water consumption , and the suitable soil water content is 70 % -80 % of the maximum water holding capacity in the field . Popcorn grain filling period should be the key to good water twice: first during flowering to seed formation stage, water is the key to promoting the grains; the second time in the milk stage, water is the key to increased grain weight. The flowering period irrigation should be different depending on the cockroach, and it should be used flexibly. The sandy loam and light loam should increase the number of irrigation; the clay and loam can be filled with water in a timely manner; the large population should increase the number of irrigation and irrigation. In addition, if there is too much rain in the corn flower grain period, attention should be paid to timely drainage.

　　 5. Remove empty stalks and small plants. There are always a certain number of plants in the corn field to form empty stalks or low-small plants with inconsistent ears. They not only consume nutrients and water in vain, but also affect the photosynthesis of other plants. Therefore, after pollination, Low and small plants should be removed early, and the limited nutrients and water should be concentrated to the normal plants, so that the ears are large and multi-seed.

　　 6. Weeding in shallow cultivating. In the late stage of corn grouting, it is smoothed once to break the soil compaction, loose soil, weeding and weeding, promote soil nutrient conversion and root absorption, prevent premature aging and increase grain weight. When you are shallow, you should prevent excessive root damage and break the blade.

　　 7. Control pests and diseases. The main pests and diseases of summer maize flower grain stage are corn borer, armyworm, cotton bollworm, aphid, size spot and rust. DDVP 600 to 800 times the base of filaments dropwise with 50% corn borer insect strains of the spinning rate of 20%. In the filling stage, when the drill Ear corn borer, with 50% or 50% DDVP phoxim 800 to 1000 times per 10 ml, corn Ear perfusion. Foliar spray 50% phoxim 1500 times solution to control armyworm, cotton bollworm, 40% omethoate 1500 ~ 2000 times liquid to control aphids. Corn size spot disease is controlled by spraying with 50 % carbendazim or 70 % thiophanate-methyl WP 500 times. Corn rust mu triadimefon available 20% EC 100 ml of 75 ~ 50 kg of water spraying.

　　 8. Harvest at the right time. The mature external appearance of corn is characterized by loose coloration of the leaves, hardening of the grains, and brightening of the cortex. A black layer appears at the section where the grain meets the cob, indicating that the corn has entered the ripening stage and the corn can be harvested. If the green leaves are good and the growing season is allowed, you can postpone the harvest for another 5 to 7 days, which will increase the yield.

Author: Chen Maochun   Source of information: Farmers Daily