水分胁迫对银杏叶片叶肉细胞超微结构的影响

应用温室盆栽方法,研究了土壤水分胁迫对4个银杏品系1年生实生苗叶片超微结构的影响,结果表明:(1)在正常土壤水分条件下,银杏各品系叶肉细胞及细胞核正常,核膜清晰,少数叶绿体中含淀粉粒和嗜锇颗粒,细胞质中含较多电子密度强的黑色物质;(2)在土壤含水量为田间持水量60%的水分条件下,银杏各品系叶肉细胞及细胞核基本正常,核膜基本清晰,叶绿体片层较清晰,叶绿体含少量嗜锇颗粒和淀粉粒,叶绿体外膜、细胞核膜和细胞壁上附着电子密度强的黑色物质;(3)在土壤含水量为田间持水量40%的条件下,银杏各品系叶肉细胞核膜大部分消失,多数叶绿体模糊,片层开始紊乱,所含嗜锇颗粒有增大、增多趋势;(4)在土壤含水量为田间持水量20%的条件下,银杏各品系细胞核膜基本消失或消失,多数叶绿体外膜变得模糊,片层基本消失,叶绿体中嗜锇颗粒明显增多,少数叶绿体中虽含有片层却出现膨胀现象;(5)从各品系叶肉细胞超微结构的综合情况分析,44号和11号品系耐旱能力强于32号和55号品系。

The effect of water stress on mesophyll cell ultrastructure of Ginkgo

One year old seedlings of Ginkgo biloba L.which grew in a pot under greenhouse conditions with varying soil water levels was used to study the effects of water stress on ultrastructure of mesophyll cell.Four soil water levels,i.e.,80%,60%,40% and 20 % of field capacity,were employed,and the time of treatment was 110 days.The results showed that at the soil water level of 80% of field capacity,the karyon was normal,and the karyotheca was clear.Some starch particles and plastoglobulis were seen in few chloroplast,and much atrament was seen in the cytoplasm,too.At the soil water level of 60% of field capacity,the mesophyll cell and karyon were normal,and the karyotheca and chloroplast lamellae were clear basically.There were few plastoglobulis and starch particles in the chloroplast,and the atrament was seen in the cytoplasm,cell wall and chloroplast ectoblast,too.At the soil water level of 20% of field capacity,much of karyotheca and chloroplast lamellae disappeared,and the plastoglobulis became much more and bigger.At the soil water level of 40% of field capacity,the karyotheca,chloroplast ectoblast and chloroplast lamellae disappeared basically,and there were more and more plastoglobulis in the chloroplast.