Akbari Alireza, Gharanjik Shahrokh, Koobaz Parisa, Sadeghi Akram
Department of Plant Breeding, Shahrood University, Shahrood, Iran.
Department of Molecular Physiology, Agricultural Biotechnology Research Institute of Iran (ABRII), Education and Extension Organization (AREEO), Karaj, Iran.
Heliyon. 2020 Feb 20;6(2):e03445. doi: 10.1016/j.heliyon.2020.e03445. eCollection 2020 Feb.
Plant growth promoting (PGP) effect of on wheat growth in different conditions has been mostly reported although mechanisms which caused wheat cultivars differently response to a PGP has been less studied. In this study, the effect of two strains, previously reported as PGPR, on the growth of four salt-sensitive commercial wheat cultivars under normal and saline conditions was investigated. Strain C-2012 differently affected the growth of the cultivars in the normal and stress conditions. Cultivars Gonbad with the highest (63%) and Zarin without increased dry biomass upon C-2012 treatments were selected for further study. Salinity significantly decreased seedling fresh and dry weight, K and chlorophyll content and glutathione S-transferase activity. Moreover, the stress increased proline and Na content and peroxidase (POX) and ascorbate peroxidase (APX) activity in both cultivars. Strain C-2012, generally, ameliorated the negative effect of the stress with increased chlorophyll and carotenoid and reduced Na content and APX and SOD activity in both cultivars, however, its effect on biomass was different. Increase in SOD, APX and POX activities in bacterial inoculated-Zarin, but not Gonbad, under normal conditions suggested that this cultivar may recognize strain C-2012 as a gentle stressor and not as a PGPR. These results showed that the responses of the wheat cultivars to a defined PGPR is different in the physiological, phenotypic and molecular level. Based on the results, the evaluation of the effect of a bio-fertilizer on each wheat cultivar is necessary prior to use in a commercial field.
虽然关于植物促生（PGP）对不同条件下小麦生长的影响已有较多报道，但导致小麦品种对PGP产生不同反应的机制却鲜有研究。在本研究中，我们调查了两种先前报道为植物根际促生细菌（PGPR）的菌株对四个盐敏感商业小麦品种在正常和盐胁迫条件下生长的影响。菌株C - 2012在正常和胁迫条件下对各品种的生长有不同影响。选择经C - 2012处理后干生物量增加最多（63%）的Gonbad品种和未增加干生物量的Zarin品种进行进一步研究。盐胁迫显著降低了幼苗的鲜重和干重、钾含量、叶绿素含量以及谷胱甘肽S - 转移酶活性。此外，胁迫还增加了两个品种中脯氨酸和钠的含量以及过氧化物酶（POX）和抗坏血酸过氧化物酶（APX）的活性。一般来说，菌株C - 2012减轻了胁迫的负面影响，增加了两个品种的叶绿素和类胡萝卜素含量，降低了钠含量以及APX和超氧化物歧化酶（SOD）活性，然而，其对生物量的影响有所不同。在正常条件下，接种细菌的Zarin品种中SOD、APX和POX活性增加，而Gonbad品种未增加，这表明该品种可能将菌株C - 2012识别为轻度胁迫源而非PGPR。这些结果表明，小麦品种对特定PGPR在生理、表型和分子水平上的反应是不同的。基于这些结果，在商业田间使用前，有必要评估生物肥料对每个小麦品种的效果。
