摘要
在营养液水培条件下,研究了不同Zn^(2+)活度（pZn^(2+)9.7,pZn^(2+)11.0和pZn^(2+)>11.5）对水稻根叶的生长发育和若干生理特性的影响。结果表明:低Zn^(2+)活度下,对水稻秧苗的出叶速度减慢,但不同基因型间存在明显差异,极度缺锌（pZn^(2+)>11.5）时,敏感品种只生长3.5叶,而耐低锌品种生长4.5叶左右;轻度缺锌或缺锌初期叶绿素含量上升和根系氧化力下降,严重缺锌,则叶绿素含量显著降低,根系氧化力明显增加,且敏感品种比耐缺锌品种的变化更为明显。低Zn^(2+)活度增加地下部干物质的积累,pZn^(2+)从9.7下降到11.0,耐低锌品种的地上部干重虽下降,但因地下部干重显著增加,故总干重相近,锌敏感品种则地上部干重显著下降,而地下部干重增加不明显,所以总干重显著下降。严重缺锌（pZn^(2+)>11.5）时,所有供试水稻品种的干重均极显著地下降,敏感品种比耐低锌品种下降得更多。因此,缺锌条件下的秧苗出叶速度和干物质积累可作为筛选和鉴定耐缺锌品种的有效指标,pZn^(2+)11.0可能是一个筛选锌高效基因型的临界锌离子活度。
Six rice genotypes with different Zn efficiency were cultivated at different Zn2+ activities (pZn2+9.7, pZn2+11. 0 and pZn2+>11.5) in nutrition solution. Effect of different Zn2+ activities on the growth and some physiological characteristics of leaf and root of rice were studied. It was found that the ability of rice tolerance to Zn deficiency significantly differed among the rice genotypes. The growth rate of leaf significantly decreased at low Zn2+ activity, and there were obvious differences among the genotypes. The Zn-inefficient rece genotypes could only grow up to 3. 5 leaves and Zn-efficient rice genotypes could grow to 4. 5 leaves at pZn2+>11.5. The chlorophyll content slightly increased at pZn2+ from 9. 7 to 11. 0, but decreased at pZn2+>11. 5. Root oxidizing power (ROP) considerably increased at severe Zn deficiency (pZn2+>11.5). At seedling age of 39, it was interesting that ROP decreased about one-fold for the Zn-efficient genotypes but increased markedly for Zn-inefficient genotypes when plants were grown at pZn2+ 11.0. Dry matter (DM) accumulation of roots increased when Zn2+ activities were lower than pZn2+11.5 for all the genotypes tested. However, Shoot DM of Zn-efficient rice genotypes significantly decreased but their root DM significantly increased when pZn2+ decreased from 9.7 to 11.0. Shoot DM of Zn-inefficient rice genotypes significantly decreased and no significant increase in root DM were observed when pZn2+decreased from 9. 7 to 11. 0. Therefore, the DM ofwhole plant for Zn-efficient rice genotypes had not significantly decreased while that for Zn-inef-ficient rice genotypes had significantly decreased at relatively low Zn2+ activities. At pZn2+> 11. 5, the DM of all rice genotypes significantly decreased, especially for Zn-inefficient rice genotypes. It could be concluded that the growth rate of rice leaf and DM accumulation of shoot at relative low Zn activity could be used as the index for identifying Zn-efficient rice genotypes. Further, pZn2+11.0 might be a critical Zn2+ activity to screen Zn-efficient rice genotypes.
出处
《作物学报》
CAS
CSCD
北大核心
1999年第4期466-473,共8页
Acta Agronomica Sinica
基金
国家自然科学基金
浙江省自然科学基金 (编号:39598)
关键词
水稻
品种
锌营养效率
出叶速率
干物质产量
Rice genotypes
Zn-ef ficiency
Leaf growth rate
Dry matter yield
