摘要
6-BA处理(10 mg/L)使供试品种株高、单株叶面积、鲜质量和干质量均有所降低。其中,处理后35 d的单株鲜、干质量明显低于对照。6-BA处理各品种的Chl a含量和Chl b含量在测定后期与对照相比表现增加趋势。6-BA处理各品种的光合速率(Pn)下降是其植株干质量明显降低的主要原因。6-BA处理对各品种叶绿素合成和暗反应的负向效应较小,而气孔导度(Gs)表现与Pn趋势相同,表明底物CO2传输能力下降,是6-BA处理植株干物质累积量较对照植株下降的重要原因。6-BA处理增加了处理后期过氧化氢酶(CAT)活性,CAT活性与MDA含量呈显著负相关(r=-0.738 1*),表明6-BA处理下细胞膜脂过氧化程度的降低,较大程度上是通过增加CAT活性所致。研究表明,与细胞分裂相比,光合碳同化作用受到过量6-BA的抑制程度更大。生产中,应根据小麦的熟期和叶片衰老特征,合理施用外源细胞分裂素类物质的浓度和数量。
Compared to control（CK）, the plant heights, leaf areas per plant, fresh weights and dry weights per plant of the tested cultivars in exogenous 6-BA treatment（ 10 mg/L）were all decreased. The fresh weights and dry weights per plant at 35 d after treatment were much lower than CK. Meanwhile, the chlorophyll a and chlorophyll b contents at late phase after 6-BA treatment showed an increase tendency compared to CK. It is found that the decrease of photosynthetic rate（Pn） in tested varieties in 6-BA treatment was the main reason of the reduction of dry matter production per plant. The tested 6-BA treatment had little adverse effects on chlorophyll synthesis and photosynthetic dark reaction in photosynthesis,and Pn showed same change pattern with stomatal conductance（Gs） in the measurement points. It was suggested that the decrease of CO2 transportation capacity by 6-BA was the main reason of lower in Pn and dry matter production per plant than CK. The 6-BA treatment increased the leaf catalase（CAT）activity at the late phase after treatment. There was a significant negative correlation between CAT activities and MDA concentration（r = -0.738 1^＊ ）, indicating that the decrease of over-oxidization degree of cell membrane system in 6-BA treatment was due to largely by the increase of CAT activity. In this study,it is found that the inhibition effect on photosynthesis by overdose exogenous 6-BA was much more than that on cell division. In wheat production, the concentration and amount of exogenous cytokinin materials applied should be carefully determined depending on the maturation properties and leaf senescence characteristics of the cultivars in future.
出处
《华北农学报》
CSCD
北大核心
2007年第5期1-7,共7页
Acta Agriculturae Boreali-Sinica
基金
国家粮食丰产科技工程项目(2004BA520A07-04)
河北省自然科学基金项目(C2006000434)
关键词
6-BA
小麦
生长
生理参数
细胞保护酶活性
6-BA
Wheat
Growth
Physiological parameter
Protection enzyme activity of cell
