近等基因系抗旱性小麦氮素营养遗传性状的研究 Ⅳ.硝酸还原酶活力与小麦抗旱性指标的研究

用盆栽试验在无氮（Ｎ０）、每公斤土壤０．１５ｇ氮（Ｎ１）、０．３０ｇ氮（Ｎ２）和干旱胁迫（正常供水Ｗ１、轻度干旱Ｗ２、中度干旱Ｗ３、重度干旱Ｗ４）以及品系抗旱性差异（ＴＡＭ品种的高抗Ｖ１和低抗Ｖ３）的条件下研究冬小麦抗旱性和硝酸还原酶活性（ＮＲＡ）的关系。结果表明，近等基因系抗旱性小麦高抗（Ｖ１）和低抗（Ｖ３）品系孕穗期功能叶ＮＲＡ存在显著的差异，在Ｗ２到Ｗ４的干旱胁迫过程中，Ｖ１的ＮＲＡ大于Ｖ３。Ｎ１下Ｖ１的ＮＲＡ也大于Ｖ３。对品系、干旱胁迫、氮肥３因素试验结果，通过把同一品系同一水分处理的ＮＲＡ平均消除氮素的干扰；把同一品系同一氮肥处理的ＮＲＡ平均消除水分的干扰的结果分别证明，在中等氮肥水平内，任何干旱强度（轻度、中度、重度干旱胁迫）下，高抗小麦Ｖ１的ＮＲＡ＞低抗小麦Ｖ３的ＮＲＡ。在此条件ＮＲＡ作为抗旱性的指标。同时Ｖ１和Ｖ３可用于筛选小麦抗旱的形态学、生理和生化指标。

NITROGEN NUTRITION PROPERTIES OF DROUGHT TOLERANCE WINTER WHEAT OF NEAR ISOGENIC LINESIV. STUDIES ON NITRATE REDUCTASE ACTIVITY AT THE BOOTING STAGE AS INDEX OF DROUGHT TOLERANCE OF WINTER WHEAT

Pot experiment was applied to study the relationship among NRA and drought-tolerance of winter wheat under the treatment of nitrogen fertilization (N 0 of no nitrogen, N 1 of 0.15 g/kg soil and N 2 of 0.3 g/kg soil as urea), water stress (normal irrigation W 1, slight drought W 2, medium grade drought W 3 and heavy drought W 4) and variety difference (V 1 of high and V 3 of low tolerance of TAM 108,) of near isogenic lines. Results show that the NRA of V 1 is bigger than that of V 3 during the drought stress process from W 2 to W 4. The NRA of V 1 is also greater than that of V 3 within N 1 treatment. When eliminate the influence of nitrogen and water respectively, the NRA of V 1 is bigger than that of V 3 from W 1 to W 4 within N 1. It can be concluded from the experiment that NRA is able to apply as indices of drought tolerance of winter wheat. Drought indices can be screened by use of V 1 and V 3 under any water stress within medium nitrogen fertilization rate.