Effect of phosphorus on celery growth and nutrient uptake under different calcium and magnesium levels in substrate culture

Abstract

A greenhouse pot experiment was performed to study the effect of phosphorus (P) on celery (Apium graveolens L.) growth, quality and nutrient uptake under different calcium (Ca) and magnesium (Mg) levels in substrate culture. Results showed that there were significant interactions between P and the level of Ca and Mg in the growing media. Celery above-ground fresh weight, total dry biomass, leaf area, and P, Ca and Mg concentrations in celery leaves significantly increased from 0 to 124 mg/l P application. The opposite trends were observed for root/shoot ratio, leaf chlorophyll, carotenoids, soluble protein, soluble sugar, vitamin C, and nitrogen and potassium concentration in celery leaves. Medium Ca and Mg level (Ca 320 and Mg 192 mg/l) significantly increased celery above-ground fresh weight, total dry biomass and leaf area compared to low (Ca 160 and Mg 96 mg/l) and high (Ca 640 and Mg 384 mg/l) levels. This study suggested that 124-248 mg/l P applications under medium Ca and Mg level were appropriate for celery nutritional requirements.