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1.棉花根际細菌总数,一方面是愈近根面愈多,愈远愈少;另一方面是随到棉花发育时期的不同作有規律的变化,出苗后渐增,至开花期达于最大,以后又慢慢减少,R/S最高可达127强。2.孢子細菌数相反,根面最少,距根面愈远愈多。3.氨化細菌数在棉花根际细菌总数中占絕对优势,往往达后者的80—90%,其数量上的变化也和后者完全一致。4.棉花根面沒有发現亚硝酸化細菌和硝酸化細菌。根际之中虽然有,但为量不多。5.棉花根部分泌有抑制纖維素分解細菌的物貭,因此棉花根面上沒有发現纖維素分解细菌,根际內也很少,并且在距根十厘米以內的土壤中;数量上的变化也不大。其量随植物的生长而增加,增加的趋势是开花期以前緩慢,結铃以前剧速上升。6.棉花根际沒有找到好气性自生固氮菌。因为原来土壤中就沒有它,或者极少。
1. Cotton rhizosphere total bacteria, on the one hand, the more proximal root more, less and less; on the other hand is with the cotton development period for the regular changes, increased after emergence, up to the flowering stage in The largest, and then slowly reduced, R / S up to 127 strong. 2 spores the contrary, the root of the least, more and more from the root surface. 3. Ammonia bacterial count in cotton rhizosphere bacteria accounted for the absolute advantage, often up to 80-90% of the latter, the quantitative changes are exactly the same with the latter. 4.Not nitrosated bacteria and nitrobacteria were found in cotton root surface. Although there are in the rhizosphere, but not much. 5. cotton roots inhibit secretion of cellulose decomposition of bacteria, so no cellulolytic bacteria found in the root surface of cotton, the rhizosphere is also very small, and within 10 cm from the root of the soil; the number of changes Not large. The amount increases with the growth of the plant, the trend of increase is slow before the flowering period, the dramatic rise before the bell. 6. Cotton root can not find aerobic autotrophic bacteria. Because the original soil does not have it, or very little.