水分和光照对厚皮甜瓜苗期植株生理生态特性的影响

以厚皮甜瓜‘西博洛托’为试材,研究了温室内育苗基质含水量和光照强度对厚皮甜瓜苗期植株生长发育和生理生态特性的影响.结果表明:不同基质含水量和光照强度对厚皮甜瓜苗期植株生长发育影响显著,随基质含水量的降低,苗期植株叶绿素a、叶绿素b和总叶绿素含量升高,叶片相对含水量和比叶面积下降,基质含水量为60%～80%时,幼苗净光合速率最高;随着光照强度的减弱,幼苗的叶绿素a、叶绿素b、总叶绿素含量以及叶片相对含水量、比叶面积和胞间CO2浓度升高,叶绿素a/b和净光合速率下降.在不同处理中,以80%基质含水量 100%温室光照处理的幼苗生长最健壮,壮苗指数、净光合速率等指标最高.

Effects of moisture and light intensity on ecophysiological characteristics of muskmelon seedlings

The muskmelon variety 'Xiboluotuo' was used as a test material in order to study the combined effects of substrate moisture and light intensity on growth,development and ecophysiological characteristics of muskmelon seedings in greenhouse.The results showed that the different substrate moisture and light intensity remarkably influenced the growth and development of muskmelon seedlings.With reduction of substrate moisture,chl a,chl b and chl a b increased,while relative water content(RWC)of leaf and specific leaf area(SLA)declined.Under 60%-80% water-holding capacity of substrate,net photosynthetic rate was the highest.With the decrease of light intensity,chl a,chl b,chl a b,RWC,SLA and intercellular CO2 concentration(Ci)went up,while chl a/b and net photosynthetic rate reduced.Among all the treatments,muskmelon seedlings with 80% water-holding capacity of substrate and 100% light density in greenhouse presented the most strong growth vigor,the highest healthy index and net photosynthetic rate.