关键词: 玉米, 结实习性, 重叠作用, SSR标记

Abstract:

Barren tip phenomenon of the ear in maize (Zea mays L.) caused the yield loss and affected the quality of commodity grain remarkably. This phenomenon is generally regarded as a quantitative character easily affected by planting density, fertilizer and water supply, light and temperature conditions, etc. However, we found that this phenomenon varied a lot among varieties and inferred that it was caused by the difference of maize fructification habit. Based on this understanding, maize varieties were classified into two types, definite fructification type (ab. DF type) and indefinite fructification type (ab. IDF type), mainly according to the development states of the kernels on tip part of the ear. In order to probe the inheritance pattern of maize ear fructification habit, two inbred lines, lx01-3 (DF type) and wx04-1 (IDF type), and their F₁, F₂, BC₁ and BC₂ populations were analyzed on the ear fructification type under a planting density of 30000 plants per hectare in this experiment. The results showed that all ears of F₁ were IDF type which means IDF type is dominant over DF type; the ratios of IDF type versus DF type ears followed a 15:1 in F₂ and a 3:1 in BC₁ population while all ears were IDF types except one in BC₂ population, which indicates the trait of fructification habit probably controlled by two pairs of duplicate dominant genes. Two SSR markers, bnlg1601 and umc1663, were found closely linking with the genes controlling the trait of maize fructification habit. Thereby, the two genes were preliminarily located on chromosome 3 and 8 respectively.

Key words: Maize, Fructification habit, Duplicate effect, SSR marker