Kagawa University

About: Kagawa University is a education organization based out in Takamatsu, Japan. It is known for research contribution in the topics: Cancer & Population. The organization has 6028 authors who have published 11918 publications receiving 224111 citations. The organization is also known as: Kagawa Daigaku.

Chapter 2 Silicon as a beneficial element for crop plants

Abstract: Silicon (Si) has not been proven to be an essential element for higher plants, but its beneficial effects on growth have been reported in a wide variety of crops, including rice, wheat, barley, and cucumber. Si fertilizer is applied to crops in several countries for increased productivity and sustainable production. Plants take up Si in the form of silicic acid, which is transported to the shoot, and after loss of water, it is polymerized as silica gel on the surface of leaves and stems. Evidence is lacking concerning the physiological role of Si in plant metabolism. Since the beneficial effects of this element are apt to be observed in plants which accumulate Si, the silica gel deposited on the plant surface is thought to contribute to the beneficial effects of Si, which may be small under optimized growth conditions, but become obvious under stress conditions. In this review, the effects of Si under biotic stresses (disease and insect damage) and abiotic stresses including climate stresses (typhoon and cool summer damage), water deficiency stress, and mineral stresses (deficiency of P and excess of P, Na, Mn, N and Al) are discussed.

Regulation of Ascorbate-Glutathione Pathway in Mitigating Oxidative Damage in Plants under Abiotic Stress

Abstract: Reactive oxygen species (ROS) generation is a usual phenomenon in a plant both under a normal and stressed condition. However, under unfavorable or adverse conditions, ROS production exceeds the capacity of the antioxidant defense system. Both non-enzymatic and enzymatic components of the antioxidant defense system either detoxify or scavenge ROS and mitigate their deleterious effects. The Ascorbate-Glutathione (AsA-GSH) pathway, also known as Asada–Halliwell pathway comprises of AsA, GSH, and four enzymes viz. ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase, play a vital role in detoxifying ROS. Apart from ROS detoxification, they also interact with other defense systems in plants and protect the plants from various abiotic stress-induced damages. Several plant studies revealed that the upregulation or overexpression of AsA-GSH pathway enzymes and the enhancement of the AsA and GSH levels conferred plants better tolerance to abiotic stresses by reducing the ROS. In this review, we summarize the recent progress of the research on AsA-GSH pathway in terms of oxidative stress tolerance in plants. We also focus on the defense mechanisms as well as molecular interactions.