The United Graduate School of Agricultural Science, Laboratory of Field Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan.
Department of Genetics and Plant Breeding, Faculty of Agriculture, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, 1706, Bangladesh.
Appl Biochem Biotechnol. 2018 Dec;186(4):999-1016. doi: 10.1007/s12010-018-2784-5. Epub 2018 May 26.
Four selected Amaranthus tricolor cultivars were grown under four irrigation regimes (25, 50, 80, and 100% field capacity) to evaluate the mechanisms of growth and physiological and biochemical responses against drought stress in randomized complete block design with three replications. Drought stress led to decrease in total biomass, specific leaf area, relative water content (RWC), photosynthetic pigments (chlorophyll a, chlorophyll b, chlorophyll ab), and soluble protein and increase in MDA, HO, EL, proline, total carotenoid, ascorbic acid, polyphenols, flavonoids, and antioxidant activity. However, responses of these parameters were differential in respect to cultivars and the degree of drought stresses. No significant difference was observed in control and LDS for most of the traits. The cultivars VA14 and VA16 were identified as more tolerant to drought and could be used for further evaluations in future breeding programs and new cultivar release programs. Positively significant correlations among MDA, HO, compatible solutes, and non-enzymatic antioxidant (proline, TPC, TFC, and TAC) suggested that compatible solutes and non-enzymatic antioxidant played vital role in detoxifying of ROS in A. tricolor cultivar. The increased content of ascorbic acid indicated the crucial role of the ASC-GSH cycle for scavenging ROS in A. tricolor.
四种精选的苋菜品种在四种灌溉制度（田间持水量的 25%、50%、80%和 100%）下生长，以随机完全区组设计进行了 3 次重复，以评估其在干旱胁迫下的生长和生理生化响应机制。干旱胁迫导致总生物量、比叶面积、相对水含量（RWC）、光合色素（叶绿素 a、叶绿素 b、叶绿素 ab）和可溶性蛋白减少，而 MDA、HO、EL、脯氨酸、总类胡萝卜素、抗坏血酸、多酚、类黄酮和抗氧化活性增加。然而，这些参数的响应因品种和干旱程度的不同而不同。在对照和 LDS 下，大多数性状没有显著差异。VA14 和 VA16 品种被鉴定为对干旱更具耐受性，可用于未来的育种计划和新的品种发布计划中的进一步评估。MDA、HO、相容性溶质和非酶抗氧化剂（脯氨酸、TPC、TFC 和 TAC）之间存在显著正相关，这表明相容性溶质和非酶抗氧化剂在苋菜品种的 ROS 解毒中发挥了重要作用。抗坏血酸含量的增加表明 ASC-GSH 循环在苋菜清除 ROS 中起着关键作用。
