| Abstract: | The effects of 10 mM nitrate on the growth and nitrogenous componentsof Zea mays L. var. W64A wild type (normal) were compared tothose on its opaque-2 (high lysine) mutant during the first10 d of seedling growth at a constant temperature of 26 °Cand with a 16 h photoperiod. Nitrate supply had no effect onthe growth of embryonic axes in both lines till day 6. Growthof both lines was enhanced slightly after that time, however.Increases in 80% (v/v) ethanolsoluble and protein nitrogen werealso observed only after day 4 when the supply of nitrogen fromthe storage proteins in the endosperm was limiting. Nitratehad no effect on the synthesis of chlorophyll during leaf developmentbut it did increase the total chlorophyll in mature and senescingprimary leaves. The increase in nitrogenous components or chlorophyllin opaque-2 was more pronounced than in the normal type. Itmight be related to the lower proline or higher lysine in themutant. |
