Effects of calcium on growth, photosynthetic characteristics and quality ofaquicultural garlic seedlings

Effects of different calcium (Ca) levels on calcium content, growth, photosynthetic characteristics and qualities of garlic seedlings were studied using nutrient solution culture. Six different Ca2+ concentration treatments: 0, 1.0, 2.0, 3.0, 4.0 and 5.0 mmol/L(T0, T1, T2, T3, T4, T5) were designed in the experiment. The results show that the Ca contents of garlic seedlings are increased with the increase of calcium concentration, and the Ca content reaches the maximum in the 5.0 mmol/L treatment. Within the calcium adding range of 0-3.0 mmol/L, the increments of pseudostems and leaves, pigment contents and photosynthetic parameters of leaves enhanced correspondently with the calcium concentrations, while in the range of 3.0-5.0 mmol/L, the three items decreased with the increase of the calcium concentrations. The contents of allicin, soluble sugar, vitamin C, free amino acid, soluble protein in pseudostems and leaves improved with the calcium concentrations increased from 0 to 3.0 mmol/L, and the highest increased values of these contents are 50.3%, 84.7%, 92.7%, 53.5%, 69.4% and 66.1%, 113.1%, 105.8%, 66.1%, 60.1%, while these indexes are also reduced when the calcium concentration is higher than 3.0 mmol/L. Thus, calcium could effectively improve the growth, photosynthesis and qualities of garlic seedlings, and the treatment of 3.0 mmol/L calcium concentration is the best.