关键词: 玉米, 根系, 土壤质地

Abstract: Corn was planted in containers with a volume of 3 m × 2 m × 1 m , in which different textural soils including light loam, loam and light clay were filled as the natural status. The effect of soil textural on corn root was studied. The results showed that the morphology, distribution, growth of corn root system were significantly different among three kinds textural soils. Corn root in light clay changed direction frequently during growth process so that it had more curved root system compared with that in light loam and loam, which characterized by "more deeper in light clay soil, more finer root diameter". More sub-roots in basal and less sub-roots in deeper soil were also observed in light loam than that in loam and light clay soil. The sequence of average root diameter(ARD) was light clay＞loam＞light loam. At jointing stage, the vertical and horizontal distribution of corn root cultivated in light loam was the most extensive, followed by loam and light clay. However, no significant difference was found among three kinds textural soils after male tetrad stage. The portion of root in top soil increased with more physical light clay component in soil. Growth dynamic of corn root in light loam was characterized by "earlier development and earlier senescence". Daily increase rate of root length density in light loam was far higher than that in loam and light clay, which reached 538.6 m·m-3·d-1 before jointing stage and root amount reached maximum at silking stage, then root began senescent. Growth dynamic of corn root in light clay was characterized by "later development and later senescence", that daily increase rate of root was low in early stage, root amount reached maximum at doughy stage and senesce rate was far lower than that of light loam during late stage. Root in loam had a balanced growth during the whole period.

Key words: Corn, Root system, Soil texture