Abstract:

To investigate the effects of arbuscular mycorrhizal fungi （AMF） on ion absorption and movement of cotton seedlings under salt and alkali stress， the pot experiment was conducted. ‘Xinluzao 45’ was as material to inoculate Funneliformis mosseae， and the control was not inoculated AMF. The seedlings of 3-leaves were treated by salt and alkali stress with 0， 50， 100， 150， 200 mmol·L^-1， and the changes of seedling growth and ion content under different treatments were analyzed. The results showed that， with the increase of salt and alkali stress， the root infection rate of cotton decreased gradually and the mycorrhizal dependence increased. With the increase of salinity and alkali stress， the biomass of cotton seedlings decreased gradually， and AMF inoculation could significantly promote the growth and development of cotton. Under various salt and alkali stress treatments， AMF inoculation significantly increased the biomass of cotton seedlings. The contents of Na⁺ and Na⁺/K⁺， Na⁺/Ca²⁺， Na⁺/Mg²⁺ in organs of cotton seedlings were significantly decreased， and the contents of K⁺， Ca²⁺， Mg²⁺ in organs of cotton seedlings were significantly increased. The transport of Na⁺ from underground to surface was decreased， while the transport of K⁺， Ca²⁺ and Mg²⁺ from underground to surface was increased. In conclusion， salt and alkali stress could inhibit the transport of K⁺， Ca²⁺ and Mg²⁺ from underground to above-ground. Inoculation with AMF inhibited the uptake and upward transport of Na⁺ by cotton roots， and promoted the uptake and upward transport of K⁺， Ca²⁺ and Mg²⁺ by cotton roots. Thus， Na⁺/K⁺， Na⁺/Ca²⁺， Na⁺/Mg²⁺ could be reduced， the damage of Na⁺ to cotton plants could be alleviated， and the growth and development of cotton seedlings can be promoted.

Key words: saline alkali content, ion transport ratio, infect, cotton

摘要：

为探究丛枝菌根真菌（arbuscular mycorrhizal fungi， AMF）对棉花苗期逆境离子吸收和运转的影响，采用盆栽试验，以棉花‘新陆早45号’为材料，接种摩西斗管囊霉，以不接种AMF为对照，待棉花生长至3叶期进行不同水平（0、50、100、150、200 mmol·L^-1）盐碱胁迫，分析不同处理下棉花幼苗生长及叶、茎、根离子含量的变化。结果表明，棉花根系侵染率随盐碱胁迫程度的增加而逐渐降低，菌根依赖性随盐碱胁迫程度的增加而增加。随着盐碱胁迫程度的增加，棉花幼苗生物量逐渐降低，而接种AMF可显著促进棉花生长发育。在各盐碱胁迫处理下，接种AMF 显著提高了棉花幼苗生物量；显著降低棉花幼苗各器官的Na⁺含量及Na⁺/K⁺、Na⁺/Ca²⁺、Na⁺/Mg²⁺，显著提高棉花幼苗各器官的K⁺、Ca²⁺、Mg²⁺含量；降低了Na⁺由地下向地上的运输， 同时增加K⁺、Ca²⁺、Mg²⁺由地下向地上的运输。综上，盐碱胁迫可抑制K⁺、Ca²⁺、Mg²⁺由地下向地上部的运输，接种AMF能够抑制棉花根系对Na⁺的吸收及向上运输，促进根系对K⁺、Ca²⁺、Mg²⁺的吸收及向上运输，从而降低Na⁺/K⁺、Na⁺/Ca²⁺、Na⁺/Mg²⁺，缓解Na⁺对棉花植株的伤害，促进棉花幼苗的生长发育。

关键词: 盐碱含量, 离子运输比, 侵染, 棉花