Impact of rice husk polymer composite application under deficit irrigation on productivity and stress tolerance of some sugarcane varieties

Abstract

The superabsorbent polymer composite based on rice husk (RPC) and loaded with urea (RPUC) as environmental-friendly products were evaluated on three sugarcane varieties productivity  ​and stress tolerance under deficit irrigation in the greenhouse during 2019 and open-field during 2020/2021 at El-Sabahia Agricultural Research Station of Alexandria (31°, 13N latitude), Sugar Crops Research Institute, Agricultural Research Center, Egypt. Four levels of RPC or RPUC (0 (control), 1, 2, and 4gm) under three irrigation intervals (2,3, and 4 weeks) were carried out in the greenhouse. The data showed that water stress at 3 weeks irrigation interval has a negative effect and is non-significant on growth parameters when applied 2 g or 4 g of RPC and  RPUC as well as increment of stalk characteristics. So, the composite levels were used for the field experiment. The treatment RPC and RPUC in the soil had a remarkable effect in improving all growth and quality parameters of sugarcane varieties at 3 weeks irrigation interval. Statistical analysis of RPC and RPUC has recorded the highest average cane yield in variety GT54-9 (52.89 ton/fed) followed by G2003-4 (43.62 ton/fed) then G2004-14 (34.88ton/fed).  Application of 4g RPUC and 2g RPC significantly increased sugar yield by 64.53 and 46.04%, respectively as compared to untreated ones. Treatment with different RPC levels and 4g RPUC showed two positive marker bands at values Rf 0.86 and 0.93 which can be considered as indicated for drought-tolerant treated varieties. So RPC and RPUC can be utilized as effective means for the water deficit characterized locations.