Physiological response of late sown wheat to exogenous application of silicon

Abstract

Late planting of wheat in rice-wheat cropping system is perhaps one of the major factors responsible for low crop yield. The main cause of reduction in yield is due to supra-optimal conditions during the reproductive growth. High temperature during reproductive phase induces changes in water relations, decreases photosynthetic rate, and transpiration rate, stomatal conductance and antioxidative defence system. Silicon (Si), being a beneficial nutrient not only provides significant benefits to plants growth and development but may also mitigate the adversities of high temperature. A field study was conducted at Agronomic Research Area of University of Agriculture; Faisalabad, Pakistan to assess the performance of late sown wheat with the soil applied Si. Experiment was comprised of three sowing dates; 10 th Nov (normal), 10 th Dec (late), 10 th Jan (very late) with two wheat varieties (Sehar-2006 and Faisalabad-2008), and an optimized dose of Si (100 mg per kg soil), applied at different growth stages (control, crown root, booting and heading). Results indicated that 100 mg Si per kg soil at heading stage offset the negative impact of high temperature and induced heat tolerance in late sown wheat. Silicon application improved 34% relative water contents (RWC), 30% water potential, 26% osmotic potential, 23% turgor potential and 21% photosynthetic rate, and 32% transpiration rate and 20% stomatal conductance in wheat flag leaf than control treatment. Further it was observed that Si application preventing the oxidative membrane damage due to enhanced activity of antioxidant enzymes, i.e. 35% superoxide dismutase (SOD) and 38% catalase (CAT). In conclusion results of this field study demonstrated that soil applied Si (100 mg per kg soil) at heading stage enhanced all physiological attributes of wheat flag leaf. Which in turn ameliorated the adverse effects of high temperature in late sown wheat. Study depicted that Si can be used as a potential nutrient in order to mitigate the losses induced by high temperature stress.

Influence of silicon treatments on some growth, physiological and biochemical traits of five Egyptian wheat varieties

“…G9 and MS1 varieties showed highest stability (4%) when compared with the other varieties. Our results agree with Gong et al (2005) and Sattar et al (2017) who stated that silicon appears to be involved in the fortification of plants against oxidation of cell membranes, leading to the protection of cell structures than various plant structures. Liang et al (2007) concluded that using Si leads to its deposition in cell membrane, certification and hardening beside decrease of membrane damage in shoots; without Si cell membrane is hurt and material leakage from cell to outside increases.…”

“…Similar conclusion was obtained by Gao et al (2006) noticed that the addition of Si increased water use efficiency by reducing leaf transpiration because silica-cuticle double layer formed on leaf epidermal tissue, the water flow rate in the xylem vessel and increased leaf water potential in potted wheat. Also, Sattar et al (2017) stated that application of Si enhanced the osmotic, relative water contents, turgor and water potential of wheat (T. aestivum) flag leaf, deposition of (Si) on leaf surface might reduce transpiration through controlling molecules of water.…”

Ecophysiological study of the impact of SiK^® fertilization on Castanea sativa Mill. seedling tolerance to high temperature

“…Vertical bars represent standard error (SE) (n = 4). et al (2016) and Sattar et al (2017), who proved that Si fertilization in cacao and wheat plants interfered in stomatal dynamics and photochemical reactions, therefore regulating photosynthesis.…”

Silicon-Mediated Improvement in Tolerance of Economically Important Crops Under Drought Stress

“…On the other hand, various studies have exposed that by absorbing Si, photosynthetic pigments can be increased in various plant species (Hasanuzzaman et al, 2018;Merwad et al, 2018). The application of Si on wheat (T. aestivum) plants showed better result by improving the leaves chlorophyll content (Ma et al, 2016), and photosynthesis rate (Sattar et al, 2017). Likewise, Maghsoudi et al (2016) demonstrated that Si leaf application increased photosynthesis pigments (chlorophyll a, b and total land carotenoids) and chlorophyll stability index (CSI) in different wheat (T. aestivum) cultivars under drought conditions.…”

“…Generally, plants maintain a high water level through osmotic adjustment under dry stress circumstances (Blum, 2017). Although, high drought circumstances trigger a considerable reduction in water content of leaf including water potential in various plants (Abid et al, 2018 Application of Si enhanced the osmotic, relative water contents, turgor and water potential of wheat (T. aestivum) flag leaf (Sattar et al, 2017). Such as the water content of wheat (T. aestivum) was increased during drought (Ratnakumar et al, 2016).…”