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承德地区是东北大豆产区的南缘,全区山地丘陵为主,土地零散,地形和气候极为复杂,南北之间差别极大。其气候最大特点是:夏季七、八月雨热同期,气温最高月和降水最多月都在七月。五、六月气温回升但缓慢,降水也少。九月降雨渐少,但气温逐渐下降并来霜,这就形成了大豆一年一作的特点。一、承德地区大豆生长特点及低产原因当地大豆品种的生态型多是开花较晚的中、晚熟类型,北部则是早熟类型。其生长过程有明显的三个不同阶段。即始花前的缓慢生长阶段,单株日增鲜重仅0.66克,从始花(七月初)到结荚期(立秋前)为迅猛生长阶段,茎叶猛增,同时开花结荚,单株日增鲜重为4克。八、九月为稳健生长阶段,籽粒逐渐成熟,茎叶不再增长,但能维持20—40天的旺盛时期,很有利于产量的形成。叶片到气温下降时才变黄脱落。整个生长过程是一个明显的S形。承德地区大豆低产的限制因素是水、肥不足和播种管理粗放。具体表现在三方面:一是片面强调了大豆的耐瘠性和适应性广,把大豆种在玉米长不起来的
Chengde region is the southern edge of the northeast soybean production area, the region mainly mountain hills, scattered land, terrain and climate is extremely complex, very different between North and South. Its most prominent feature is the climate: rainy days in July and August in the same period, the highest temperature and precipitation in most months in July. In May and June temperatures rose slowly but with less precipitation. The rainfall in September is getting smaller, but the temperature is gradually dropping and frosting, which makes the soybean a year. First, the characteristics of Chengde soybean growth and low yield Local soybean varieties are mostly ecotypes flowering later, the late maturity type, the north is a precocious type. There are three distinct stages of its growth. That is, the slow growth phase before flowering, the daily fresh weight per plant was only 0.66 grams, from the beginning of flowering (early July) to the podding stage (before autumn) as a rapid growth stage, stems and leaves soared, at the same time blossom pod, single Daily fresh weight of 4 grams. August and September for the steady growth stage, the gradual maturity of the grain, stems and leaves no longer grow, but can maintain a strong period of 20-40 days, is conducive to the formation of yield. The leaves turn yellow when the temperature drops. The entire growth process is an obvious S-shape. The limiting factors for low yields of soybeans in Chengde are the lack of water and fertilizers and the extensive management of seeding. Specific performance in three aspects: First, one-sided emphasis on the barren and adaptability of soybeans, the soybean species can not grow in corn