Chintakovid Nutwadee, Tisarum Rujira, Samphumphuang Thapanee, Sotesaritkul Thanyaporn, Ullah Hayat, Datta Avishek, Cha-Um Suriyan
National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Khlong Luang, Pathum Thani 12120 Thailand.
Agricultural Systems and Engineering, Department of Food, Agriculture and Bioresources, School of Environment, Resources and Development, Asian Institute of Technology, Khlong Luang, Pathum Thani 12120 Thailand.
Physiol Mol Biol Plants. 2025 Jun;31(6):877-893. doi: 10.1007/s12298-025-01618-x. Epub 2025 Jul 16.
Rhizome yield traits and curcuminoids in turmeric ( L.) rhizome are the major determining factors for its production, especially under water-limited environments. Chitosan, a member of biostimulants, regulates physiological adaptation strategy and works as a chemical elicitor in several plant species under withholding water. The objective of the present study was to assess growth characteristics, physiological adaptation, rhizome attributes, total curcuminoids content, and upregulated expression levels of curcuminoids-related genes in turmeric under water withholding using chitosan biostimulant. The response of two contrasting genotypes, high curcuminoids cv. Surat Thani (ST) and low curcuminoids cv. Pichit (PJT) was evaluated under two water management practices (withholding water for 45 days [WD] and daily irrigation/well-watered [WW] condition) with or without foliar application of chitosan at 20 mg L. Leaf area and pseudostem dry weight in ST grown under WD were significantly decreased by 39% and 26%, respectively, over WW condition without chitosan application, whereas the two water management practices resulted in similar responses in plants treated with 20 mg L chitosan foliar spray. Fresh weight and dry weight of rhizome under WD were decreased by > 40% over WW treatment. Leaf temperature and crop water stress index were sustained at a low level by 20 mg L chitosan application, resulting in the preservation of leaf osmotic potential and photon yield of PSII, especially in PJT. In contrast, gas exchange parameters such as transpiration rate, net photosynthetic rate, and stomatal conductance were severely affected by WD, which in turn reduced the amount of total soluble sugar. Under WD, the expression levels of curcuminoids-related genes were increased, whereas total curcuminoids content in the turmeric rhizomes was significantly decreased. The results indicate that foliar application of chitosan as a biostimulant plays a positive role in reducing the harmful impact of drought stress and improving growth characteristics; however, the degree of positive effect is dependent on genotype, application dose, and level of water availability.
The online version contains supplementary material available at 10.1007/s12298-025-01618-x.
姜黄根茎产量性状和姜黄素类物质是其产量的主要决定因素，尤其是在水分受限的环境中。壳聚糖作为生物刺激素的一种，可调节生理适应策略，并在几种缺水植物中作为化学诱导剂发挥作用。本研究的目的是评估使用壳聚糖生物刺激素在水分胁迫下姜黄的生长特性、生理适应性、根茎属性、总姜黄素类物质含量以及姜黄素类物质相关基因的上调表达水平。在两种水分管理措施（45天水分胁迫[WD]和每日灌溉/充分浇水[WW]条件）下，评估了两种对比基因型，即高姜黄素类物质品种素叻他尼（ST）和低姜黄素类物质品种披集（PJT）在叶面喷施或不喷施20 mg/L壳聚糖情况下的响应。与未喷施壳聚糖的WW条件相比，WD条件下生长的ST的叶面积和假茎干重分别显著降低了39%和26%，而在喷施20 mg/L壳聚糖叶面喷雾处理的植株中，两种水分管理措施导致的响应相似。与WW处理相比，WD条件下根茎的鲜重和干重降低了>40%。喷施20 mg/L壳聚糖可使叶片温度和作物水分胁迫指数维持在较低水平，从而保持叶片渗透势和PSII的光量子产量，尤其是在PJT中。相比之下，蒸腾速率、净光合速率和气孔导度等气体交换参数受到WD的严重影响，进而降低了总可溶性糖的含量。在WD条件下，姜黄素类物质相关基因的表达水平增加，而姜黄根茎中的总姜黄素类物质含量显著降低。结果表明，叶面喷施壳聚糖作为生物刺激素在减轻干旱胁迫的有害影响和改善生长特性方面发挥了积极作用；然而，积极作用的程度取决于基因型、施用剂量和水分可利用水平。
在线版本包含可在10.1007/s12298-025-01618-x获取的补充材料。
