1, soybean flowers without real reason
1.1 internal cause
Internal cause is the guide of improper and cause of the local climate environment does not adapt.Soybean flowers and false phenomenon is put in bigger difference between the varieties, in variety of varieties, the early maturity varieties is lighter.In June 2013, xuzhou zhang town, about 66.67 hm2 soybean, about 33.33 hm2 plots by the daughter of shandong heze breeding farm planting beans, this variety is late varieties, vegetative growth and reproductive growth for a longer time at the same time, in suitable conditions, nitrogen fertilizer, the more the vegetative growth, often affect the photosynthetic product off to flowers, flowers fall off and immature pods [2].
1.2 the external cause
Because temperature is too high, too little rain, improper cultivation measures, lack of nutrients or imbalance, serious diseases, the soybean flowers and false [3].
(1) the temperature is too high.Soybean flowering pollination of optimum temperature for 20 ~ 25 ℃, 35 ℃ and stamens will die, suitable relative humidity is 70% ~ 90%.Zhang town grown daughter pudding period at the end of July, about 20 d at this time the town temperatures continue high temperature of 37 ℃, the soybean to flower or spend less, or flowering, but not real, so lead to excess plant vegetative growth, branches and leaves black thick, insect pest is more serious.
(2) too little rain.Flowering period of soybean moisture is critical to the drum, if this time meet drought can't timely watering, due to a lack of nutrients in the water can't transfer, can cause a lot of fallen petal falls pod or drum difficulties, make reproductive growth retardation, vegetative growth, TanQing, late, late immature pods.The daughter of zhang town grow beans of flowering period was hit the worst high temperature and drought in 20 years, which can lead to the flowering results [4].
(3) the improper cultivation measures.One is the planting density is too large.Different varieties, there are and the suitable planting density and density affect ventilation pervious to light, make the field microclimate, weakened photosynthesis, flowers loss or immature pods.Second, fertilizer is not reasonable.If too much water, especially nitrogen application time is too late, or too much will cause the moderate growth, stem leaf and drum difficult, TanQing late, don't mature harvest on time.Three is the continuous cropping.Plant diseases and insect pests of soybean continuous cropping, leading to a serious, especially soil borne diseases.
2, prevent technology
2.1 choose suitable varieties, improve seed purity
Choose good varieties is to prevent the soy is not one of the most important aspects of the firm, according to the different climate characteristic and plant habit, select drought waterlogging resistance, resistance to disease resistance, early maturity varieties in quality, and establish and improve the seed breeding base, guarantee provided by the purity of seeds and their good qualities.In recent years, suitable for xuzhou cultivated soybean varieties have a beans, LuNing 1 number 12, medium yellow 37 and medium yellow 13, etc.
2.2 adjust the planting structure, reasonable arrangement of crop
Reasonable planting structure, diversified forms of planting, can effectively reduce the occurrence of soil spread diseases and insect pests, avoid soil nutrient consumption of a single, keep the ecological balance and sustainable utilization of soil resources.Under this principle, reasonable arrangement of stubbles and take more than three years or rotation systems, not heavy as much as possible to meet crop planting (the next year to meet crop planting), reduce the pod and false phenomenon.
2.3 timely planting
Summer soybean high requirement to the short day, sowing early early flowering, also can cause the old infuriatingly strong seedlings and seedlings.Zhang town of summer soybean suitable sowing date on June 5 to 15, if it is late varieties should be sown after June 20.
2.4 scientific fertilization, balanced nutrition
Follow the "optimum nitrogen, increasing organic fertilizer, NPK under phosphorus and micronutrient fertilizer" principle.First of all, by the high quality organic fertilizer with suitable amount of nitrogen and phosphorus as a basal, cultivating strong seedling.General organic fertilizer of 22.5 t/hm2, potassium sulphate compound fertilizer 150 kg/hm2, molybdenum fertilizer and boron fertilizer.The second is to look at the seedling fertilizer.If the young thin, can be in before blossomming or early flowering topdressing urea around 75 kg/hm2.Flowers sprayed molybdenum fertilizer fertilizer, molybdenum with xerox 750 g/hm2 to foliar spraying of water 450 kg/hm2, spray once every 5 ~ 7 d, even 2 ~ 3 times.If water sufficient cause flourishing long, should be used in early flowering multi-effect azole 750 g/hm2 to foliar spray of water 450 kg/hm2, can reduce the plant height, prevent flowers fall off, reduce the empty abortive rate.
