关键词: 玉米, 盐胁迫, Na+含量, K+含量, Ca²⁺含量, 种子萌发

Abstract:

Maize (Zea mays L.) seeds of a salt tolerant cultivar Denghai 9 and a salt sensitive cultivar Jundan 18 were germinated and grown in 1/4 and 1/2 Hoagland solutions with 0, 50, 100, 150, and 200 mmol L^-1 NaCl, respectively. The contents of Na⁺, K⁺, and Ca²⁺ in testa, embryo, endosperm, roots, root crown, and leaf were measured by ICP Mass. The Na⁺ content increased accordantly with the NaCl concentration in culture solution. In young seedlings, Na⁺ content in root and root crown was higher than that in leaf; in germinating seeds, it was significantly higher in embryo than in testa and endosperm. The capacity of Na⁺ accumulation in roots was strong, while the capacity of Na⁺ rejection in embryo was weak. The testa could also accumulate some Na⁺. The K⁺ and Ca²⁺ contents in germinating seeds and young seedlings of maize decreased obviously under NaCl stress, and the Ca²⁺ content showed changes in a large scale, which was 38.4%–55.9% in Denghai 9 and 65.6%–78.2% in Jundan 18. The capacities of Na⁺ accumulation and rejection as well as the Ca²⁺ selective absorption might be related to salt-tolerance of maize cultivars

Key words:

Maize, Salt stress, Na⁺ content, K⁺ content, Ca²⁺ content, Seed germination