Biochar and super absorbent polymer improved growth, yield, and phytochemical characteristics of Satureja rechingeri Jamzad in water-deficiency conditions

Biochar is a stable, carbon-rich byproduct of organic matter thermal degradation. The application of biochar demonstrates improved soil properties, water holding capacity, crop plant growth, and nutrient retention. The purpose of this study was to determine the effect of biochar and super absorbent on several phytochemical parameters of S. rechingeri Jamzad when grown in a water-stressed conditions. During two consecutive cropping seasons (2017-2019), an experiment was conducted using a split-plot factorial design with a randomized complete block design in three replications. Irrigation (100%, 80%, and 60% of irrigation requirement) [I] was used in the main plots, while subplots received a combination of two levels of cow manure biochar (0 and 10 t ha(-1)) [B] and two levels of stockosorb (R) super absorbent (0 and 60 mg per plant) [SA]. Despite the relatively high diversity of compounds found in savory essential oils, the mean comparison revealed that IxBxSA had a significant effect on the majority of the primary components found in savory essential oils. Carvacrol (67.2-85%) was the first major constituent of savory essential oils in the two years, followed by 1, 8-cineole, terpinen-4-ol, gamma-terpinene, and linalool. The experimental results indicated that drought stress increased the percentage of essential oil in two years but decreased dry matter and essential oil yield. Evidently, biochar and SA alone exhibit a similar effect on the content of savory essential oils, increasing growth rate and essential oil content (%). In general, this study confirmed that the combination of biochar and SA resulted in the highest savory leaf area, dry weight, and essential oil yield when compared to the application of biochar or SA alone under drought stress conditions.

Automated summary

The study showed that the combination of biochar and super absorbent had a significant impact on the phytochemical parameters of S. rechingeri Jamzad under water-stressed conditions, resulting in the highest savory leaf area, dry weight, and essential oil yield.