水分胁迫对玉米杂交种叶绿素含量的影响

 叶绿素含量是反映植物抗旱性的一个重要指标。为了研究玉米杂交种的抗旱性，筛选出抗旱性较强的玉米杂交种用于生产，本研究选用7个玉米杂交种，在遮雨棚中进行盆栽试验，通过控制浇水，研究水分胁迫对玉米杂交种叶绿素含量及抗旱性的影响。结果表明，花期干旱处理的叶绿素a，总叶绿素含量以及叶绿素a/b分别为5.464 mg/L，7.853 mg/L和2.286，均高于苗期干旱处理（分别为2.373 mg/L，4.769 mg/L和0.990）。在不同干旱处理进程中，苗期干旱有利于叶绿素b含量的提高，而在花期干旱中，随着干旱处理时间以及玉米的逐渐成熟，叶绿素含量显著下降。在不同杂交种间，无论是苗期干旱处理，还是花期干旱处理，长城706的叶绿素含量最高，苗期干旱处理下，其叶绿素a，叶绿素b以及总叶绿素含量分别为8.831，3.705，12.533 mg/L，花期干旱处理下，三者分别为12.608，4.277，16.881 mg/L；长城799，农单5号、北玉16号、海禾1号次之；而路单8号和会单4号的叶绿素含量最低。而叶绿素a/b在苗期干旱处理、花期干旱处理进程中，以及在不同品种间均无明显变化。由于叶绿素含量的高低可以反映不同玉米品种对水分胁迫的敏感程度，因此，从干旱处理中的叶绿素含量变化可以看出，长城706的抗旱性最强，长城799，农单5号、北玉16号、海禾1号的抗旱性较强，而路单8号和会单4号的抗旱性较差。叶绿素含量可以作为筛选玉米品种抗旱性的指标之一。

Effects of Water Stress on Chlorophyll Content of Maize Hybrid

Chlorophyll content is an important indicator to reflect drought resistance in plant. In order to study the drought resistance of maize hybrids and select the strong drought resistant maize hybrid used in agricultural production, seven maize hybrids were selected and planted in pot, placed in canopy, by controlling the watering to research effects of water stress on chlorophyll content and ratio of maize hybrids. The results indicated that the content of chlorophyll a and total chlorophyll, and the ratio of chlorophyll a and b in blossom period drought (they were 5.464mg/L, 7.853 mg/L and 2.286, respectively) were higher than that of in seedling stage drought (they were 2.373 mg/L, 4.769 mg/L and 0.990, respectively). In the different drought processing, seedling stage drought was conducive to improve chlorophyll b content. But chlorophyll content decreased significantly along with the prolonging of drought process time and the maturing of maize in blossom period drought. In different hybrids, both seedling stage drought and blossom period drought, chlorophyll content of Changcheng 706 was the highest (they were 8.831, 3.705,12.533 mg/L in seedling stage drought, and they were 12.608, 4.277,16.881 mg/L in blossom period drought), that of Changcheng 799, Nongdan No.5, Beiyu No.16 and Haihe No.1 were the second, and that of Ludan8 and Huidan 4 were the lowest. But the chlorophyll a/b showed no significant change in seedling stage drought, in blossom period drought, as well as in different cultivars. Chlorophyll content can reflect the water stress sensitivity in different maize varieties, therefore, according to the varieties of chlorophyll content in the drought processing, Changcheng 706 had the strongest drought resistance, Changcheng 799, Nongdan No.5, Beiyu No.16 and Haihe No.1 had stronger drought resistance, too, but Ludan No.8 and Huidan No.4 had poor drought resistance. The ratio of chlorophyll a and b had no significant difference among different hybrids. Chlorophyll content could be used as one of the indexes to select drought resistance of maize.