Physiological and biochemical responses of hybrid maize (Zea mays L.) varieties grown under heat stress conditions

Abstract

Maize (Zea mays L.) is the second most commonly produced and consumed crop after wheat globally and is adversely affected by high heat, which is a significant abiotic stress factor. This study was carried out to determine the physiological and biochemical responses of hybrid corn varieties under heat stress (‘HS’) compared to control (‘C’) conditions during the 2020 and 2021 growing seasons. The experiment was conducted under natural conditions in the Southeastern region of Turkey, where the most intense temperatures are experienced. This experiment used split plots in randomized blocks with three replications, with ‘HS’ and ‘C’ growing conditions applied to the main plots and the different hybrid corn varieties (FAO 650) planted on the sub plots. Mean values of days to 50% tasseling (DT, day), grain yield (GY, kg ha−1), leaf water potential (LWP, %), chlorophyll-a (Chl-a, mg g−1), cell membrane damage (CMD, %), and total phenol content (TPC, μg g−1) were significantly different between years, growing conditions, and hybrid corn varieties. Changes in the climate played a significant role in the differences between the years and growing conditions (GC), while the genetic characteristics of the different corn varieties explained the differences in outcomes between them. The values of DT, GY, LWP, Chl-a, CMD, and TPC ranged from 49.06–53.15 days, 9,173.0–10,807.2 kg ha−1, 78.62–83.57%, 6.47–8.62 mg g−1, 9.61–13.54%, and 232.36–247.01 μg g−1, respectively. Significant correlations were recorded between all the parameters. Positive correlations were observed between all the variables except for CMD. The increased damage to cell membranes under ‘HS’ caused a decrease in the other measured variables, especially GY. In contrast, the GY increased with decreased CMD. CMD was important in determining the stress and tolerance level of corn varieties under ‘HS’ conditions. The GY and other physiological parameters of ADA 17.4 and SYM-307 candidate corn varieties surpassed the control hybrid corn cultivars. The results revealed that the ADA 17.4 and SYM-307 cultivars might have ‘HS’-tolerate genes.

A quick and effective method for thermostability differentiation in cucumber (Cucumis sativus L.)

“…High temperature is a major factor affecting the development of agriculture globally (Barnabas et al, 2008; Zhang et al, 2019). With the elevating ambient temperature, the negative effects of high temperature on the growth and development of crops are becoming increasingly obvious, especially in yield and quality (Battisti and Naylor, 2009; Herman et al, 2017; Zhao et al, 2017; Ezin et al, 2022; Tas, 2022). Germplasm resources with different heat resistance provide important materials for breeding (Rana et al, 2011; Harohalli Masthigowda et al, 2022).…”

Maize and heat stress: Physiological, genetic, and molecular insights

“…An increase in CMD caused decrease in LWP, and inhibition of chlorophyll synthesis as well as degradation of chlorophyll a/b. Moreover, total phenol content (TPC) was also found to be decreased in susceptible genotypes under heat stress (Tas, 2022).…”

“…Exposure to heat stress severely affects physiological processes such as seed germination and vigor, root growth, leaf enlargement, reproductive development, ASI, photosynthesis, grain filling duration, and rate of grain filling, which eventually reduce yield and grain quality (Figure 2). At the cellular level, the rapid production of reactive oxygen species (ROS) leads to cellular membrane damage (CMD), protein degradation, and inhibition of chlorophyll synthesis (Tas, 2022). Heat stress also interferes with gaseous exchange by altering stomatal conductance, which leads to decrease in tissue water potential of plants (Urban et al., 2017).…”

Transcriptional dynamics of maize leaves, pollens and ovules to gain insights into heat stress-related responses

“…The morphological and physiological effect of maize under heat stress is discussed in detail by El-Sappah et al. (2022) and Tas (2022) .…”