At the time of rearing the plant, as function as water to the plant body after the thing and the budding which offer the seed which makes the preservation water material constituent for plant rearing come in contact where the germinating rate of the seed of the above-mentioned plant is high, and a resource of the growth promotor under the environment where the moisture of arid belt and the like is little, is shown, it is to offer the seed which makes the preservation water material constituent for plant rearing come in contact which is superior in seeding operating efficiency. It makes the preservation water material constituent for plant rearing come in contact which includes the water absortion power resin grain which possesses the physical properties of specification on the surface of the seed of the plant. Physical properties of specification under pressurizing 2.07kPa 60 minutes pure water absorption magnification ratio (AAPw) is 60 - 200 [g/g].植物の育成に際して、乾燥地帯等の水分の少ない環境下においても、上記植物の種子の発芽率が高い植物育成用保水材組成物を付着させた種子を提供すること、発芽後の植物体への水、及び成長促進剤の供給源としての機能を発揮するとともに、播種作業性に優れた植物育成用保水材組成物を付着させた種子を提供することである。植物の種子の表面に特定の物性を有する吸水性樹脂粒子を含む植物育成用保水材組成物を付着させる。特定の物性とは2.07kPa・60分間の加圧下純水吸収倍率(AAPw)が60~200[g/g]である。
