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我县地处浅山丘陵区,土地瘠薄、耕层浅而粘重、灌溉条件差、生产水平低,常年油菜单产一直在30斤上下徘徊。低产原因(一) 播期晚本区油菜播种适期为9月下旬至10月5日之间,但因作物复种指数过高、腾茬晚,大面积油菜播期常推迟到10月下旬或11月上旬,致使冬前苗小苗弱而发生严重冻害。(二) 密度小移栽时没有保证密度,且腾茬晚移栽晚造成弱苗和越冬死苗,使密度过小,覆盖面积小,地面蒸发大,干旱加剧。(三) 苗期干旱10月至翌年元月,是油菜苗期阶段,这时本区总降水为29.6毫米,仅占年降水总量的29.5%,加之无灌溉条件,干旱加剧了越冬死苗。
My county is located in shallow hills, land barren, shallow and sticky farming, poor irrigation conditions, low production levels, perennial peanut yield has been hovering around 30 pounds. Reason for low yield (A) Late sowing date The sowing period of rapeseed in this area is between late September to October 5, but due to crop multiple cropping index is too high, stubble late, large area rape sowing is often delayed until late October or Early November, resulting in pre-winter seedling weak and serious freezing damage. (B) the density of small transplanting no guarantee of density, and late transplanting transplanting late planting caused by weak and overwintering dead seedlings, the density is too small, covering a small area, ground evaporation, increased drought. (C) seedling drought October to January the following year, is the stage of rapeseed seedlings, when the total precipitation in this area was 29.6 mm, accounting for only 29.5% of the total annual rainfall, combined with non-irrigated conditions, drought exacerbated winter dead seedlings .