Chitosan nanoparticles improve physiological and biochemical responses of Salvia abrotanoides (Kar.) under drought stress.

BACKGROUND: The use of organic nanoparticles to improve drought resistance and water demand characteristics in plants seems to be a promising eco-friendly strategy for water resource management in arid and semi-arid areas. This study aimed to investigate the effect of chitosan nanoparticles (CNPs) (0, 30, 60 and 90 ppm) on some physiological, biochemical, and anatomical responses of Salvia abrotanoides under multiple irrigation regimes (30% (severe), 50% (medium) and 100% (control) field capacity). RESULTS: The results showed that drought stress decreases almost all biochemical parameters. However, foliar application of CNPs mitigated the effects caused by drought stress. This elicitor decreased electrolyte conductivity (35%), but improved relative water content (12.65%), total chlorophyll (63%), carotenoids (68%), phenol (23.1%), flavonoid (36.4%), soluble sugar (58%), proline (49%), protein (45.2%) in S. abrotanoides plants compared to the control (CNPs = 0). Furthermore, the activity of antioxidant enzymes superoxide dismutase (86%), polyphenol oxidase (72.8%), and guaiacol peroxidase (75.7%) were enhanced after CNPs treatment to reduce the effects of water deficit. Also, the CNPs led to an increase in stomatal density (5.2 and 6.6%) while decreasing stomatal aperture size (50 and 25%) and semi-closed stomata (26 and 53%) in leaves. CONCLUSION: The findings show that CNPs not only can considerably reduce water requirement of S. abrotanoides but also are able to enhance the drought tolerance ability of this plant particularly in drought-prone areas.

Agronomic and environmental factors affecting cultivation of the winter mushroom or Enokitake: achievements and prospects.

The global interest in production of the winter mushroom or Enokitake (Flammulina filiformis previously known as Flammulina velutipes) is increasing owing to its nutritional and medicinally important bioactive compounds along with a marketable texture and flavor. This review presents the state of knowledge on achievements in solid-state cultivation and submerged cultures of Enokitake and how they are influenced by environmental factors and agronomic characteristics. A wide range of basic lignocellulosic substrates and supplementations have been reviewed in order to formulate an efficient and locally available substrate. Domestication of wild types of Enokitake and its economic and research implications are also discussed. Besides, the influence of environmental and agronomic factors on production and efficacy of the most important biologically active metabolites of Enokitake in both solid-state cultivation and submerged cultures has been discussed. Some of shortcomings of studies reporting cultivation of Enokitake are described and their contribution to future prospects is also discussed in this review.