Effects of Nutrient Solution Levels on the Growth, Yield and Mineral Contents in Hydroponically-Grown Bush Snap Bean.

Abstract

This study was conducted to determine the influence of nutrient solution levels on the growth, yield, mineral contents and some physiological characters of bush snap bean, and to determine their effects on water and nutrient uptake. The treatments used were 1/4, 1/2, 1, 11/2 and 2 times of the standard Enshi-shoho solution concentration. Increasing nutrient strength reduced vine length, but increased plant fresh and dry weights, leaf chlorophyll, photosynthetic rate, transpiration rate and stomatal conductance at flowering and early pod development stages. Water and nutrient uptake increased with increasing nutrient levels. N, P and K contents in the leaf blades and young pods increased while Ca and Mg decreased with increasing nutrient strength. Leaf blades had higher total-N, Ca and Mg contents, while pods did higher P and K. Percent pod set was slightly improved in 1/2 to 2-strength treatments. Pod yield was comparable among 1/2, 1, 11/2 and 2-strength treatments. The results indicate that 1/2 strength is sufficient for high yield of bush snap bean.