海盐胁迫对苏牧2号象草叶片解剖结构的影响

Influence of Sea Salt Stress on Anatomical Structure of Leaf of Elephant Grass Sumu No.2

以苏牧2号象草和N51(对照)象草为材料,研究了不同海盐浓度对其幼苗叶片解剖结构的影响。结果表明:随海盐浓度升高,苏牧2号和N51表皮气孔总密度、刚毛总密度及泡状细胞长度总体呈增大的趋势,其中N51象草气孔总密度在10g/L处理下显著下降;苏牧2号和N51单位面积的维管束数目总体表现为逐渐增大,只有N51的海盐处理6g/L比4g/L的维管束数高6.86%。相同海盐浓度胁迫时,6g/L和10g/L处理下,苏牧2号气孔总密度显著高于N51,泡状细胞的相对长度和单位面积维管束数目均高于N51,表皮刚毛总密度在10g/L处理下显著高于N51。这一结果表明,在中、高等海盐浓度胁迫下,苏牧2号比N51具有相对较高气孔密度和刚毛密度,提高了其净光合速率,降低了其蒸腾作用,单位面积上维管束数目较多,保证了水分和养分的运输,使其具有较高的抗生理干旱的能力,是其耐盐能力较N51强的部分原因。

Under different sea-salt concentration,the anatomical structure of leaves of Sumu No.2 and N51（CK） napier grass seedlings were studied.Along with the sea salt concentration increased,the total stoma density,total leaf hair density and motor cell length of Sumu No.2 and N51 increased except that the total stoma density was significantly decreased under 10g/L sea-salt concentration.The vascular bundle number per square millimeter of Sumu No.2 and N51 napier grass were increased with sea-salt concentration increased besides 6g/L of N51 was higher by 6.86% than that of 4g/L.Under the same sea-salt concentration,the total stoma density of Sumu No.2 was obviously higher than N51,and the vascular bundle number per square millimeter and the motor cell length of Sumu No.2 were higher than N51 under 6 g/L and 10 g/L treatments;The total leaf hair density of Sumu No.2 was significantly higher than N51 under 10g/L treatments.The result showed that relatively high stoma density,the vascular bundle number per square millimeter and the total stoma density of Sumu No.2 improved its net photosynthetic rate,ensured the moisture and nutrients transport and reduced moisture transpiration which made Sumu No.2 have high ability to resist physiological drought,which was the part of reasons that Sumu No.2 was more salt-resistant than N51.