Improving Yield Components and Desirable Eating Quality of Two Wheat Genotypes Using Si and NanoSi Particles under Heat Stress

Abstract

Global climate change is a significant challenge that will significantly lower crop yield and staple grain quality. The present investigation was conducted to assess the effects of the foliar application of either Si (1.5 mM) or Si nanoparticles (1.66 mM) on the yield and grain quality attributes of two wheat genotypes (Triticum aestivum L.), cv. Shandweel 1 and cv. Gemmeiza 9, planted at normal sowing date and late sowing date (heat stress). Si and Si nanoparticles markedly mitigated the observed decline in yield and reduced the heat stress intensity index value at late sowing dates, and improved yield quality via the decreased level of protein, particularly glutenin, as well as the lowered activity of α-amylase in wheat grains, which is considered a step in improving grain quality. Moreover, Si and nanoSi significantly increased the oil absorption capacity (OAC) of the flour of stressed wheat grains. In addition, both silicon and nanosilicon provoked an increase in cellulose, pectin, total phenols, flavonoid, oxalic acid, total antioxidant power, starch and soluble protein contents, as well as Ca and K levels, in heat-stressed wheat straw, concomitant with a decrease in lignin and phytic acid contents. In conclusion, the pronounced positive effects associated with improving yield quantity and quality were observed in stressed Si-treated wheat compared with Si nanoparticle-treated ones, particularly in cv. Gemmeiza 9.

Keywords: heat stress; late sowing; silicon; silicon nanoparticles; wheat; yield components.

Figure 1

Electrograph SDS-PAGE of glutenin protein extracted from grains of two wheat cultivars treated with silicon and nanosilicon (a) cv. Shandaweel 1 and (b) cv. Gemmeiza 9: M, protein marker; Lane 1, control; Lane 2, 1.5 mM potassium silicate; Lane 3, 1.66 mM nanosilicon; Lane 4, heated 1.66 mM nanosilicon; Lane 5, heated 1.5 mM potassium silicate; Lane 6, heated control.

Figure 2

Effects of silicon and nanosilicon on (a) water absorption and (b) oil absorption contents of flour of two wheat cultivars cv. Shandaweel 1 and cv. Gemmeiza 9 at normal and late seasons. Each value is the main of three different replicates ± SE. Columns with different letters are significantly different at p < 0.05.

Figure 3

Effects of silicon and nanosilicon on (a) lignin, (b) cellulose and (c) pectin contents in straw of two wheat cultivars cv. Shandaweel 1 and cv. Gemmeiza 9 at normal and late seasons. Data expressed as (g/1g DW). Each value is the main of three different replicates ± SE. Columns with different letters are significantly different at p < 0.05.

Figure 4

Effects of silicon and nanosilicon on stress intensity index (SII) of two wheat cultivars (Shandaweel 1 and Gemmeiza 9) grown under heat stress conditions.