Hydrogel/superabsorbent polymer for water and nutrient management in horticultural crops-review

Abstract

The hydrogel is a soil conditioner able to retain water and plant nutrients. Hydrogel is commercially available as Stockosorb/Raindrop/Agrosorb. Stockosorb releases water and nutrient to the plants, when surrounding soil near root zone of plants starts to dry up. Hydrogel polymers are synthetic, water-absorbing monomers of high molecular weight. Polymers differ from each other in the specific monomer building block, amount of water absorbed per gram of material, particle size and distribution, response to salinity and cost. Benefits derived from polymer application to soil or artificial medium include: increase in water-holding capacity, increase in pore size/number, increase in soil nutrient reserves, and reduction in soil compaction. Initial use of polymers was reported in greenhouse production in the late 1970s, but is now used in the production of fruits, vegetables, and turf. Development of application equipment has the potential to expand the use of polymers to large commercial growers. Planting of horticulture crops on steep hill slopes and lack of supplementary irrigation and application of nutrients, cause gradual decrease in their productivity. So, this review was made elucidate the effect of hydrogels (Stockosorb) on the growth, yield, quality, nutrient absorption and retention, water conservation efficiency in horticulture sector.