Synergistic Effects of Kaolin and Silicon Nanoparticles for Ameliorating Deficit Irrigation Stress in Maize Plants by Upregulating Antioxidant Defense Systems

Alleviating the drought stress and improving the plant resistance properties of Triticum aestivum via biopriming with aspergillus fumigatus

BACKGROUND

Wheat (Triticum aestivum L.) is one of the most widely grown and vital cereal crops, containing a high percentage of basic nutrients such as carbohydrates and proteins. Drought stress is one of the most significant limitations on wheat productivity. Due to climate change influences plant development and growth, physiological processes, grain quality, and yield. Drought stress has elicited a wide range of plant responses, namely physiological and molecular adaptations. Biopriming is one of the recent attempts to combat drought stress. Mitigating the harmful impact of abiotic stresses on crops by deploying extreme-habitat-adapted symbiotic microbes. The purpose of this study was to see how biopriming Triticum aestivum grains affected the effects of inoculating endophytic fungi Aspergillus fumigatus ON307213 isolated from stressed wheat plants in four model agricultural plants (Gemmiza-7, Sids-1, Sakha8, and Giza 168). And its viability in reducing drought stress through the use of phenotypic parameters such as root and shoot fresh and dry weight, shoot and root length, and so on. On a biochemical and physiological level, enzymatic parameters such as catalase and superoxidase dismutase are used. Total phenolics, flavonoids, and photosynthetic pigments are non-enzymatic parameters. Making use of molecular techniques such as reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTS

It has been found that using Aspergillus fumigatus as a biological biopriming tool can positively impact wheat plants experiencing drought stress. The total biomass of stressed wheat plants that had been bio-primed rose by more than 40% as compared to wheat plants that had not been bio-primed. A. fumigatus biopriming either increased or decreased the amount of enzymatic and non-enzymatic substances on biochemical scales, aside from the noticeable increase in photosynthetic pigment that occurs in plants that have been bio-primed and stressed. Drought-resistant genes show a biopriming influence in gene expression.

CONCLUSIONS

This is the first paper to describe the practicality of a. fumigatus biopriming and its effect on minimizing the degrading effects of drought through water limitation. It suggests the potential applications of arid habitat-adapted endophytes in agricultural systems.

Silicon and titanium nanoparticles modulated drought and chromium toxicity by adjusting physio-biochemical attributes and fatty acid profiles of black cumin (Nigella sativa L.)

Drought and chromium (Cr) stress are the main environmental issues affecting plant performance. Although the positive effects of silicon dioxide (SiO2) and titanium dioxide (TiO2) nanoparticles (NPs) are used as a promising strategy to control abiotic stresses; their synergic effects on controlling drought and Cr toxicity are unknown. This study aimed to investigate the effects of foliar applications of SiO2 (200 mg L-1) and TiO2 (60 mg L-1) NPs on growth, chlorophyll (Chl) content, lipid peroxidation, antioxidant enzyme, and fatty acid profile of black cumin (Nigella sativa L.) under drought (soil moisture at 50% field capacity (FC) and Cr toxicity as K2Cr2O7 at 10 mg L-1. The results showed that drought and Cr stress significantly reduced growth and Chl a + b, but increased malondialdehyde (MDA), electrolyte leakage (EL), and the activity of antioxidant enzymes. The use of NPs particularly SiO2 NPs modulated drought and Cr stress through enhancing Chl content and alleviating MDA, EL, and antioxidant activities. Under drought stress, SiO2 NPs enhanced shoot weight (26%), root weight (25%), seed yield (36%), Chl content (26%), but lowered MDA (22%), EL (14%), catalase (CAT, 32%), and superoxide dismutase (SOD, 33%) activity relative to non-NP application. The main changes in fatty acid profile corresponded to abiotic stresses, where they increased polyunsaturated fatty acids (PUFAs) but decreased monounsaturated fatty acids (MUFAs). Multivariate analysis showed that plant weight, seed yield, Cl content, and oleic acid negatively correlated with MDA, EL, antioxidant enzymes, and linoleic acid. In total, the use of SiO2 is recommended for modulating drought and Cr stress to reach the maximum seed yield of black cumin and a healthy fatty acid profile.