葉萵苣浮根式水耕之養分吸收

Abstract

葉萵苣行浮根式水耕，以不同濃度之Hoagland培養液測定結果，該培養液二分之一濃度生產量最高。經培養液和植體之分析計算其大致培養液吸收濃度N03-N、P、K．Ca、Mg分別為7、1.5、4.5、2.5、1me/l。浮根式水耕其主要氧來源為水表面供給為主，用馬達以循環法入方法，雖可略增加其溶氧量，但對葉萵苣之產量影響不顯著。 By using root-floating hydroponics, different concentrations of Hoagland solution were tested for nutrient absorption of leafy lettuce. Highest yield was obtained 1/2 concentration of standard solution. Results from the analysis of nutrient solution and plant suggested the optimum nutrient absorption for leafy lettuce being N03-N=7, P= 1.5, K=4.5, Ca=2.5, Mg=l me/l. Needed oxygen mainly came from the surface of water in root-floating hydroponics. Water circulating did not increase the lettuce yield.