Heat shock increases oxidative stress to modulate growth and physico-chemical attributes in diverse maize cultivars

Abstract

A b s t r a c t. The present investigation was conducted to appraise the physiochemical adjustments in contrasting maize cultivars, namely, PakAfgoi (tolerant) and EV-5098 (sensitive) subjected to heat shock. Seven-day-old seedlings were exposed to heat shock for different time intervals (1, 3, 6, 24, 48 and 72 h) and data for various physiochemical attributes determined to appraise time course changes in maize. After 72 h of heat shock, the plants were grown under normal conditions for 5 d and data for different growth attributes and photosynthetic pigments recorded. Exposure to heat shock reduced growth and photosynthetic pigments in maize cultivars. The plants exposed to heat shock for up to 3 h recovered growth and photosynthetic pigments when stress was relieved. A time course rise in the relative membrane permeability, hydrogen peroxide (H 2 O 2 ) and malondialdehyde contents was recorded particularly in the EV-5098 indicating that heat shock-induced oxidative stress. Activities of different enzymatic antioxidants greatly altered due to heat shock. For instance, an increase in superoxide dismutase activity was recorded in both maize cultivars. The activity of ascorbate peroxidase was greater in Pak-Afgoi. However, the peroxidase and catalase activities were higher in plants of . Heat shock caused a significant rise in the proline and decline in the total free amino acids. Overall, the performance of Pak-Afgoi was better in terms of having lesser oxidative damage and greater cellular levels of proline. The results suggested that oxidative stress indicators (relative membrane permeability, H 2 O 2 and malondialdehyde) and proline can be used as markers for heat shock tolerant plants.

Foliar Applied Acetylsalicylic Acid Induced Growth and Key-Biochemical Changes in Chickpea (Cicer arietinum L.) Under Drought Stress

“…Acetylsalicylic acid showed a positive effect on total phenolics and flavonoid contents under water stress condition (4A-B). The results are in agreement with finding by Hussain et al 47 …”

“…Acetylsalicylic acid showed a positive effect on total phenolics and flavonoid contents under water stress condition (4A-B). The results are in agreement with finding by Hussain et al 47 Osmotic adjustment is also an important way to resist adverse stress in plants. The osmotic adjustment substances, such as soluble protein and proline play vital roles in maintaining the osmotic equilibrium and integrity of membranes.…”

“…45 Ascorbic acid is one of important metabolites that considerably intervenes the abiotic stress in plants. 46 The results are in agreement with finding by Hussain et al, 47 who recorded increase in ascorbic acid content in maize plants exposed to high temperature stress. The present study revealed that activity of ascorbic acid was increased due to ASA ( Figure 3B ).…”

Assessment of Oxidative Stress by Detection of H2O2 in Rye Samples Using a CuO- and Co3O4-Nanostructure-Based Electrochemical Sensor

“…Abiotic stress factors, like high temperatures [8], drought [9], salinity [10], exposure to herbicides, and heavy metals [11], can disrupt the delicate equilibrium between ROS production and ROS scavenging in plants [12]. This can result in an accumulation of ROS, which can lead to oxidative damage to cellular components and impaired plant growth and development.…”