The potential of sugarcane bagasse polymer composite for sustainable of Stevia rebaudiana productivity under deficit irrigation

Abstract

Recycling of ligno-cellulosic residues and economically viable crops production with improved water use efficiency is imperative to secure high-quality sustainable food production and implement the environmental sustainability. Therefore, the objective of this work was to evaluate superabsorbent sugarcane bagasse polymer composite (SBP) on Stevia rebaudiana quality and production under deficit irrigation. The experiment was conducted at Sabahia Agricultural Research Station, Alexandria, Egypt during two seasons 2017/2018 and 2018/2019 under the greenhouse conditions. Three SBP treatments (0.0, 2.0 and 4.0 g/5 kg of soils) using three irrigation levels (100%, 70% and 50% of field capacity) were applied. Data revealed that the soil amendment with SBP enhanced and gave the highest values of stevia growth parameters, chlorophyll, total soluble carbohydrate and steviol glycoside (SVglys) under both irrigation systems in both seasons. The SBP at dosage 2 and 4% levels into the soil led to an increase of dry leaves yield by 1.5 and 1.32 fold, respectively compared to yield in untreated soil under 70% field capacity. Calculated SVglys and determined by IR was high in soil amendment with 2.0% SBP (15.60%) under 100% irrigation levels and nearly closed in 70% irrigation level (15.02%). SBP application under deficit irrigation conditions increased of amount WUE and showed improvement in peroxidase isozyme system that can be used as a biomarker for characterizing drought stress tolerance. Hence, it could be recommended that SBP can be used to enhance the stevia productivity and enabled the survival of stevia plant under deficit irrigation conditions.