Chinachanta Kawiporn, Shutsrirung Arawan, Santasup Choochad, Pathom-Aree Wasu, Luu Doan Trung, Herrmann Laetitia, Lesueur Didier, Prom-U-Thai Chanakan
Department of Plant and Soil Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand.
Center of Excellent in Microbial Diversity and Sustainable Utilization, Chiang Mai University, Chiang Mai 50200, Thailand.
Plants (Basel). 2023 Sep 29;12(19):3441. doi: 10.3390/plants12193441.
Salinity is one of the most devastating abiotic stresses hampering the growth and production of rice. Nine indole-3-acetic acid (IAA)-producing salt-tolerant plant-growth-promoting rhizobacteria (ST-PGPR) were inoculated into Thai jasmine rice ( L.) variety Khao Dawk Mali 105 (KDML105) seedlings grown under different concentrations of NaCl (0, 50, 100, and 150 mM). The ST-PGPR strains significantly promoted the growth parameters, chlorophyll content, nutrient uptake (N, P, K, Ca, and Mg), antioxidant activity, and proline accumulation in the seedlings under both normal and saline conditions compared to the respective controls. The K/Na ratio of the inoculated seedlings was much higher than that of the controls, indicating greater salt tolerance. The most salt-tolerant and IAA-producing strain, sp. ORF15-23, yielded the highest values for all the parameters, particularly at 50 mM NaCl. The percentage increases in these parameters relative to the controls ranged from >90% to 306%. Therefore, sp. ORF15-23 was considered a promising ST-PGPR to be developed as a bioinoculant for enhancing the growth, salt tolerance, and aroma of KDML105 rice in salt-affected areas. Environmentally friendly technologies such as ST-PGPR bioinoculants could also support the sustainability of KDML105 geographical indication (GI) products. However, the efficiency of sp. ORF15-23 should be evaluated under field conditions for its effect on rice nutrient uptake and growth, including the 2AP level.
盐度是阻碍水稻生长和产量的最具破坏性的非生物胁迫之一。将9株产吲哚-3-乙酸（IAA）的耐盐植物促生根际细菌（ST-PGPR）接种到在不同浓度NaCl（0、50、100和150 mM）下生长的泰国香稻（L.）品种考道克玛利105（KDML105）幼苗中。与各自的对照相比，ST-PGPR菌株在正常和盐胁迫条件下均显著促进了幼苗的生长参数、叶绿素含量、养分吸收（N、P、K、Ca和Mg）、抗氧化活性和脯氨酸积累。接种幼苗的K/Na比远高于对照，表明其耐盐性更强。最耐盐且产IAA的菌株sp. ORF15-23在所有参数上均产生了最高值，尤其是在50 mM NaCl时。这些参数相对于对照的增加百分比范围为>90%至306%。因此，sp. ORF15-23被认为是一种有前景的ST-PGPR，有望开发成为一种生物接种剂，用于提高受盐影响地区KDML105水稻的生长、耐盐性和香气。诸如ST-PGPR生物接种剂等环境友好型技术也可以支持KDML105地理标志（GI）产品的可持续性。然而，sp. ORF15-23的效率应在田间条件下进行评估，以了解其对水稻养分吸收和生长的影响，包括2AP水平。
