Abstract:As a new type of watersaving polymer materials, aquasorb can ameliorate soil structure, facilitate formation of soil aggregate, enhance water holding capacity of soil, adjust plant rhizosphere environment,,reduce the loss of soil nutrients and promote crop growth. In the experiment, microcrystalline cellulose aquasorb and straw residue aquasorb were synthesized using by orthogonal optimization. In the process, acrylic acid was employed as graft monomer, potassium persulfate (KSP) as initiator, and N,N′methylene bisacrylamide (NMBA) as crosslinking agent. The the max water absorbency of two aquasorbs (microcrystalline cellulose aquasorb and straw residue aquasorb) were 401.20g/g and 382.22g/g, respectively. In this paper, the effects of these two kinds of cellulose aquasorbs on the physicochemical properties of the substrate and growth physiological indexes of cucumber seedlings such as roots activity, seedling index and G value (the growth rate of the daily average dry mass) etc. were compared. The results indicate that after the addition of two cellulose aquasorbs in plug seedling, there are significant effects on promoting soil physicochemical properties and the growth of cucumber seedlings. After 36 days, when the mass fraction of microcrystalline cellulose aquasorb is 0.3%, the G value, seedling index and root activity of cucumber seedlings samples can reach (0.0154±0.0009)g/d, 0.4892±0.0762 and 61.82μg/(g·h), respectively. When the mass fraction of added straw residue aquasorb is 0.3%, the G value, seedling index and root activity of cucumber seedlings samples can reach (0.0156±0.0004) g/d, 0.5089±0.0985, 60.90μg/(g·h), respectively. The research results show that straw residue aquasorb can be used as a new type soil aquasorb applied in field production.