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用磷酸（Ｈ３ＰＯ４）沿行带状喷施威拉米特砂壤土，有效地促进胡萝卜（Ｄａｕｃｕｓｃａｒｏｔａ Ｌ．）、花椰菜（Ｂｒａｓｓｉｃａ ｏｌｅｒａｃｅａＬ． ｖａｒ． ｂｏｔｒｙｔｉｓ）、黄瓜（Ｃｕｃｕｍｉｓ ｓａｔｉ－ｖｕｓ Ｌ．）、 莴苣（Ｌａｃｔｕｃａ ｓａｔｉｖａ Ｌ．）和洋葱（Ａｌｌｉｕｍ ｃｅｐａ Ｌ．）出苗。成苗数通常也有所增加。在生长前期这种效果特别明显。喷施磷酸后土壤不易板结；据测定表土机械穿透阻力减小。喷施磷酸作为抗土壤板结剂显著增加胡萝卜、黄瓜、莴苣和洋葱幼苗的含磷量。喷施磷酸比撒施或沟施重过磷酸钙（Ｃ Ｓ Ｐ）的产量通常要高些。用磷量相同，沟施重过磷酸钙，胡萝卜、莴苣和洋葱的出苗数、叶片含磷量及产量都比带状喷施磷酸要低。但沟施重过磷酸钙的黄瓜，其叶片含磷量及产量均有高于喷磷酸处理的趋势。磷酸处理在土壤ｐＨ值为５．０至６。１范围内能促进胡萝卜和莴苣出苗，而；在ＰＨ值为６．６时则出苗数减低。
Spraying Willamette sandy loam along a banded line with phosphoric acid (H3PO4) effectively promoted the growth of carrot (Daucuscarota L.), Brassica oleracea L. var. Botrytis, cucumber (Cucumis sati-vus L.), lettuce Lactuca sativa L.) and onion (Allium cepa L.). The number of seedlings is usually also increased. This effect is particularly noticeable in the early stages of growth. Spraying phosphoric acid after the soil is not easy compaction; according to the determination of surface soil mechanical resistance to reduce penetration. Spraying phosphoric acid as an anti-soil caking agent significantly increased the phosphorus content of carrot, cucumber, lettuce and onion seedlings. Spraying phosphoric acid is usually higher than applying or dosing SSP. With the same amount of phosphorus, ditch overshoot superphosphate, carrots, lettuce and onion emergence, the amount of phosphorus content and leaf yield than phosphate spraying is lower. However, the ditch oversized superphosphate cucumber, its leaf phosphorus content and yield were higher than the trend of phosphoric acid treatment. Phosphoric acid treatment promoted the emergence of carrot and lettuce at soil pH values of 5.0 to 6.1, whereas the number of emergence decreased at pH 6.6.