The action of yeast elongating bacterial threads into steamed rice like a plant elongates its roots into the ground is called hazekomi and the conditions of hazekomi is called hazekomi conditions.
ちょうど植物が土中へ根を生やすように、酵母が蒸米の中へ菌糸を伸ばしていくことを破精込み（はぜこみ）といい、その態様を破精込み具合（はぜこみぐあい）という。