盐胁迫对无芒雀麦幼苗叶片形态及解剖结构的影响

Effects of Salt Stress on Leaf Morphology and Anatomical Structure of Bromus Inermis Seedlings

为了探究盐胁迫下无芒雀麦(Bromus inermis)幼苗叶片形态及解剖结构的适应性变化,本研究以‘乌苏一号’无芒雀麦(Bromus inermis Leyss.‘Wusu No.1’)为材料,分别采用NaCl∶Na_(2)SO_(4)∶Na_(2)CO_(3)=4∶1∶0(A盐),NaCl∶Na_(2)SO_(4)∶Na_(2)CO_(3)=1∶4∶0(B盐)和NaCl∶Na_(2)SO_(4)∶Na_(2)CO_(3)=1∶1∶8(C盐)3种混合盐进行胁迫处理,其中A,B盐为中性盐,C为碱性盐,每种混合盐均设置四个不同的电导率(Electrical conductivity,EC)梯度5,10,15,20 ms·cm^(-1),以浇灌自来水为对照组(CK)。试验结果表明,当C盐EC值为15 ms·cm^(-1),A和B盐EC值均为20 ms·cm^(-1)时,各处理下幼苗的生长受到明显抑制;3种混合盐处理下,随着EC的增加,中脉厚度、主脉维管束直径、上下表皮细胞厚度、木质部面积变化均呈显著下降趋势,而上角质层厚度、韧皮部面积则表现出先增后降的变化趋势。总之,EC值<10 ms·cm^(-1)时,碱性盐比中性盐更促进无芒雀麦叶片各项指标的增长,当EC值>10 ms·cm^(-1)时,碱性盐对幼苗的抑制作用显著大于中性盐。

In order to investigate the adaptive changes of leaf morphology and anatomical structure of Bromus inermis seedlings under salt stress,the Bromus inermis Leyss.‘Wusu No.1’was taken as test material,three mixed salts,NaCl∶Na_(2)SO_(4)∶Na_(2)CO_(3)=4∶1∶0(A salt),NaCl∶Na_(2)SO_(4)∶Na_(2)CO_(3)=1∶4∶0(B salt)and NaCl∶Na_(2)SO_(4)∶Na_(2)CO_(3)=1∶1∶8(C salt)were conducted.Salt A and B are neutral salts,Salt C is an alkaline salt,Four different Electrical conductivity(EC)gradients(5,10,15,20 ms·cm^(-1))were set for each mixed salt,and the control group(CK)was irrigated tap water.The results showed that seedlings’growth was significantly inhibited when the EC of C salt was 15 ms·cm^(-1)and of A and B salt was 20 ms·cm^(-1).With the increase of EC,the thickness of midrib,the diameter of vascular bundle,the thickness of upper and lower epidermis cells,and the area of xylem decreased significantly,while the thickness of the upper cuticle and the area of phloem increased first and then decreased.In conclusion,when EC value<10 ms·cm^(-1),alkaline salt promoted the growth of various indexes of Bromus inermis leaves more than neutral salt.When EC value>10 ms·cm^(-1),the inhibitory effect of alkaline salt on seedlings was significantly greater than that of neutral salt.