Department of Agronomy, Faculty of Agricultural and Environmental Science, University of Gadarif, Al Gadarif, Sudan.
Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou City, China.
PeerJ. 2022 Oct 14;10:e13793. doi: 10.7717/peerj.13793. eCollection 2022.
Salinity is one of the primary abiotic stresses that cause negative physiological and biochemical changes due to the oxidative stress caused by the generation of reactive oxygen species (ROS). The effect of jasmonic acid (JA) as foliar spray and humic acid (HA) as soil amendment on the growth and biochemical attributes of forage sorghum plants exposed to salinity stress was investigated. Soil treated with NaCl at levels of 0, 2, and 4 g NaCl kg dry soil (designated as S0, S1, and S2) and soil amendment with humic acid at 0, 3, and 6 g HA kg dry soil (designated as HA0, HA1, and HA2). The plants were sprayed with three JA levels, including 0, 5, and 10 mM JA. Salinity stress increased carotenoid and soluble protein content, superoxide dismutase (SOD) activity, and malondialdehyde (MDA) content. In contrast, salinity stress reduced plant height, leaf area, relative growth rate, proline content, and the activity of peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX). At the S2 salinity level, HA2 rate increased plant high by 9.7%, relative growth rate by 70.8% and CAT by 45.5, while HA1 increased leaf area by 12.5%, chlorophyll content by 22.3%, carotenoid content by 38.1%, SOD activity by 20.9%, MDA content by 18.0%, POD activity by 24.6% and APX value by 21.7%. At the S2 salinity level, the highest plant height, chlorophyll content, soluble protein content and APX value were recorded at 5 mM JA, while the highest leaf area, the content of carotenoid, proline, and MDA, and the activity of POD and CAT were achieved at 10 mM JA. Generally, 10 mM JA and 3 g HA kg dry soil produced the best positive effects on forage sorghum plants physiological responses. Our study suggested that jasmonic acid and humic acid at appropriate rates can successfully mitigate the adverse effects of salinity stress on forage sorghum.
盐度是导致植物产生氧化应激,从而引发一系列负面生理生化变化的主要非生物胁迫因素之一。本研究通过叶面喷施茉莉酸(JA)和土壤施用腐植酸(HA)两种方式,探究了其对盐胁迫下饲用高粱生长和生化特性的影响。土壤中添加的 NaCl 浓度分别为 0、2 和 4 g NaCl kg 干土(记为 S0、S1 和 S2),同时土壤中添加的 HA 浓度分别为 0、3 和 6 g HA kg 干土(记为 HA0、HA1 和 HA2)。用 0、5 和 10 mM JA 三种 JA 浓度对植物进行叶面喷施。盐胁迫增加了类胡萝卜素和可溶性蛋白含量、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。相反,盐胁迫降低了株高、叶面积、相对生长率、脯氨酸含量以及过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)的活性。在 S2 盐胁迫水平下,HA2 处理组使株高增加了 9.7%,相对生长率增加了 70.8%,CAT 增加了 45.5%,而 HA1 处理组则使叶面积增加了 12.5%,叶绿素含量增加了 22.3%,类胡萝卜素含量增加了 38.1%,SOD 活性增加了 20.9%,MDA 含量减少了 18.0%,POD 活性增加了 24.6%,APX 值增加了 21.7%。在 S2 盐胁迫水平下,5 mM JA 处理组的株高、叶绿素含量、可溶性蛋白含量和 APX 值最高,而 10 mM JA 处理组的叶面积、类胡萝卜素含量、脯氨酸含量和 MDA 含量、POD 和 CAT 活性最高。总的来说,10 mM JA 和 3 g HA kg 干土对饲用高粱植株的生理响应产生了最佳的积极影响。本研究表明,在适当的浓度下,茉莉酸和腐植酸可以成功减轻盐胁迫对饲用高粱的不利影响。