Assessment of physio-biochemical indicators for drought tolerance in different cultivars of maize (Zea mays L.)

Abstract

Maize is an important cereal crop all-over the world and has been recently ranked at first among all cereal crops. However, growth of maize plants is negatively affected in arid and semi-arid areas of the globe due to scarcity of water, but genetically variable cultivars/lines differ considerably to respond to water limited conditions. To evaluate the response of some commercial cultivars of maize to water deficit conditions, a pot experiment was carried out. Eight maize cultivars (Sultan, Akbar, Pearl, MMRI, Maki Pak, Sahiwal 2002, Sadaf and Neelum) were subjected to varying [100%, 75% and 60% of field capacity (FC)] levels of water deficit conditions. Drought stress significantly decreased shoot fresh and dry weights, root fresh and dry weights and chlorophyll pigments (a and b) in all maize cultivars. However, free proline, glycinebetaine (GB), total phenolics, hydrogen peroxide (H2O2), malondialdehyde (MDA) contents, activities of enzymatic antioxidants (CAT, POD and SOD) and ascorbic acid (AsA) contents increased significantly under water deficit conditions. Of all maize cultivars, cv. Sadaf was superior in terms of plant growth, while, cv. Sultan proved to be inferior to the other cultivars examined in this study. It was concluded that osmoprotectants such as proline and GB can be used as stress tolerance indicators under drought stress conditions.

Methionine-induced regulation of growth, secondary metabolites and oxidative defense system in sunflower (Helianthus annuus L.) plants subjected to water deficit stress

“…However, the present study was carried-out to assess the effectiveness of exogenously applied L-methionine in upregulation of growth and some key biochemical processes of sunflower ( Helianthus annuus L.) plants exposed to water-deficit stress. It is now well evident that drought stress can markedly suppress the growth of plants, as already observed in different crops e.g., carrot [ 56 ], radish [ 57 ], maize [ 58 ], sunflower [ 59 ], and mung bean [ 60 ]. In the present study, drought stress (60% F.C.)…”

Grain yield, anthesis-silking interval and drought tolerance indices of tropical maize hybrids

“…However, the drought tolerance characteristic of crops is probably the most difficult to identify with great precision, since grain yield is a complex trait and is influenced by the genotype by environment interaction and other mechanisms associated with heterosis (Pereira 2016). Thus, in the absence of precise information regarding the complete genetic mechanism of drought tolerance in maize, some secondary characteristics of the plant have been used as selection criteria, such as agronomic traits and molecular markers (Mikić et al 2016), morpho-physiological mechanisms (Wattoo et al 2018), and physiobiochemical indicators (Shafiq et al 2019).…”

Thiamin stimulates growth and secondary metabolites in turnip (Brassica rapa L.) leaf and root under drought stress

“…To attain optimum growth and yield production, plants require both water and nutrients in the proper amount to fulfill their basic needs. Under water‐limited conditions, a significant reduction in plant growth and yield production has been observed in different crops, for example, canola (Shafiq et al 2014), cauliflower (Latif et al 2016), maize (Shafiq et al 2018), sunflower (Kosar et al 2018) and mungbean (Sadiq et al 2019). In all these studies, it has been reported that water stress‐induced reduction in plant growth can be related to oxidative stress, nutritional imbalance, hormonal alterations, suppression/deterioration of proteins, deactivation of enzymes and disturbance in secondary metabolism.…”