Central Research and Development Department, Experimental Station, E. I. du Pont de Nemours and Company, Wilmington, Delaware 19898.
Appl Environ Microbiol. 1983 Jun;45(6):1775-9. doi: 10.1128/aem.45.6.1775-1779.1983.
Inoculation of corn (Zea mays) seeds with Azospirillum brasilense strain Cd or Sp 7 significantly enhanced (30 to 50% over controls) the uptake of NO(3), K, and H(2)PO(4) into 3- to 4-day- and 2-week-old root segments. No gross changes in root morphology were observed; altered cell arrangement in the outer four or five layers of the cortex was seen in photomicrographs of cross sections of inoculated corn roots. The surface activity involved in ion uptake probably increased, as shown by the darker staining by methylene blue of the affected area. Shoot dry weight increased 20 to 30% in inoculated plants after 3 weeks, presumably by enhancement of mineral uptake. Corn and sorghum plants grown to maturity on limiting nutrients in the greenhouse showed improved growth from inoculation approaching that of plants grown on normal nutrient concentrations. Enhanced ion uptake may be a significant factor in the crop yield enhancement reported for Azospirillum inoculation.
用固氮螺菌 Cd 或 Sp7 菌株对玉米种子进行接种，显著提高了（比对照高出 30%至 50%）3 至 4 天大和 2 周龄的根段对 NO3、K 和 H2PO4 的吸收。未观察到根形态的明显变化；在接种玉米根横切的显微照片中，观察到外皮层的第四或第五层细胞排列发生了改变。离子吸收所涉及的表面活性可能增加，这可以通过受影响区域的亚甲基蓝染色更深来证明。接种后 3 周，接种植物的地上部干重增加了 20%至 30%，可能是由于矿物质吸收的增强。在温室中用限制养分种植的玉米和高粱植物，从接种中获得的生长改善接近在正常养分浓度下生长的植物。增强的离子吸收可能是固氮螺菌接种报告的作物产量提高的一个重要因素。
