【摘 要】
：
当前，我国杂交作物的供种量已占用种量的90％以上，但常规作物的统一供种水平却十分低下，山东小麦常年种植面积6300万亩左右．占耕地面积的60％以上，约需种5亿公斤，1990年以前，统一供种量
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当前，我国杂交作物的供种量已占用种量的90％以上，但常规作物的统一供种水平却十分低下，山东小麦常年种植面积6300万亩左右．占耕地面积的60％以上，约需种5亿公斤，1990年以前，统一供种量不足20％,不少种子经营单位基本上是“杂交玉米种子公司”，基它作物种子经营量较少
At present, the supply of hybrid crops in China has occupied more than 90% of the total, but the uniform supply of conventional crops is very low. The annual planting area of Shandong wheat is about 6300 mu. Accounting for more than 60% of the arable land, about 500 million kilograms of which is required. Before 1990, the unified supply was less than 20% of the total area. Many seed management units were basically “hybrid corn seed companies”
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