[Response of chloroplast ultrastructure of ear leaves of spring maize to field managements].

Spring maize was selected as research object, and the characteristics of chloroplast ultrastructure of ear leaves were evaluated with scanning electron microscopy (SEM) as affected by irrigation, organic manure fertilization and nitrogen application. The results showed that with increasing irrigation amount, organic manure fertilization amount and nitrogen application amount, the chloroplast ultrastructure gradually became integrated, the membrane envelope of chloroplast became clear, the stroma lamellae increased and arranged regularly, the grana were clear and stacked increasingly, the starch particles increased and the osmiophilic grains decreased. Compared with other treatments, irrigation, organic manure fertilization and nitrogen application at a rate of 1200 milliliter per pot and per day, 4000 kilogram per mu and 23 kilogram N per mu could make the chloroplast ultrastructure show greater predominance. Compared with one topdressing, two topdressing and one deep application with control fertilizer made chloroplast become a more integrated membrane system. It was indicated that whether the chloroplast ultrastructure was normal was considered as an important index judging activities of plant cells, and reasonable field managements could make chloroplast ultrastructure of spring maize more stable, which was advantaged for high-efficiency production of spring maize.