[Stem characteristics of different wheat varieties and its relationship with lodging-resistance.].

Taking four outstanding varieties Aikang 58, Zhoumai 18, Yumai 49 and Bainong 418 from Huanghuai wheat area as test objects, the lodging-resistance traits of different varieties at different growth stages were investigated by combining field and laboratory methods. The results showed that stem mechanical strength was at a high level between flowering and 20 days after flowering, declined significantly in 30 days after flowering. The lodging index was minimal in flowering period, maximal in 30 days after flowering, and was at an intermediate level in the other two periods.