The protective effect of silicon (Si) against environmental stress has been observed in many crops. The objective of this work was to evaluate the impact of SiK® (potassium silicate) fertilization on the resilience capacity of chestnut plants growing under high air temperature conditions and their recovery capacity after a turnover to adequate temperatures. Castanea sativa plants were supplied with 0 mM, 5 mM, 7.5 mM, and 10 mM SiK® and exposed sequentially to 25°C, 32°C, and 25°C for 1 month each. Data suggested that silicon are involved in increasing the heat tolerance of chestnut plants by reducing the oxidative damage and improving the antioxidant enzymes and metabolites. Under heat stress (32°C), there was an increase in the catalase, ascorbate peroxidase, and peroxidase activities, as well as in the phenol content of supplemented plants, which consequently reduced the electrolyte leakage, lipid peroxidation, and hydrogen peroxide content. Additionally, a lower proline content was measured inside the leaves' tissues of Si-treated plants. Besides the resilience against heat stress, after exposure to 32°C, the recovery was also quick.
The aim of this work was to evaluate the impact of Si fertilization on the resilience capacity of chestnut plants growing under high air temperatures and its recovery capacity after returning to optimal temperatures. Castanea sativa plants were supplied with 0, 5, 7.5, and 10 mM potassium silicate (SiK ®) and exposed for a month at each temperature, 25, 32, and 25°C. The results demonstrated that phytoliths were accumulated in the leaf tissues, both on the cell wall and xylem vessels, suggesting their role in the plant's tolerance to heat. Under high temperature, Si fertilization in chestnut plants increased the gas exchange and the photochemical efficiency of the PSII as the increase of 50% on performance index suggests. The presence of Si also induced higher contents of photosynthetic pigments and promoted a better adaptation of chloroplasts to high temperatures. The present study suggests that the application of Si may be used to enhance the high temperature tolerance of chestnut plants.
Drought is an abiotic stress that may be aggravated by climate changes with increasingly warmer and drier summers. This is a severe problem in the chestnut crop in Portugal due to its need for water during this time, which is essential for good formation and development of the fruit. Si fertilization is referenced by several authors as important in the tolerance of plants under drought. The experiments were carried out in the field trial and chestnuts were fertilized with 0, 5, 7.5, and 10 mM potassium silicate (SiK), which was applied to the soil and to the leaves and exposed to a non-irrigation and an irrigation phase during the summer. Results indicate that Si fertilization increased the relative water content and water potential, while the transpiration rate, stomatal conductance, and stomatal density were reduced under deficit irrigation in Si-treated plants (10 mM SiK). Moreover, the Si induces a higher photosynthetic activity and vessel frequency with a smaller diameter, promoting a higher relative hydraulic conductivity and a lower vulnerability to cavitation. This work suggests that Si can be used as a potential source to induce drought tolerance in chestnuts.
The European chestnut (Castanea sativa Mill.) is a specie with great economic importance in Europe that have been present for thousands of years. In Portugal, the chestnut helps to maintain a positive trade balance, by contributing to the gross national product (GDP). One of the biggest threats for the chestnut is the ink disease caused by Phytophthora cinnamomi, this disease is problematic to chestnut crop with a damaging impact. Silicon (Si) is classified as a beneficial nutrient, having the ability to make plants more resistant to attacks by pathogens. Studies on the effect of silicon on chestnut are practically non-existent, so the aim of this study was to evaluate the impact of silicon in the resistance of chestnut plants to P. cinnamomi. The plants were treated by 0 mM, 5 mM, 7.5mM and 10 mM SiK ® with the analyzed mad at 0, 15 and 30 days after inoculation by P. cinnamomi. These findings showed that the Si-treated plants had higher survival rate resulted from the presence of phytoliths in root tissues, that acted as a mechanical barrier reducing the development of pathogenic structures and they arealso associated with the improvement on antioxidant activity through the increase of CAT and SOD, higher values of total phenols compounds and less oxidative damage. The presence of Si in PDA medium reduced the growth of P. cinnamomi all over the time, presenting high PI. This work shows that the Si fertilization in chestnut plants contributes to increase the resistance against P. cinnamomi infection.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.