作 者 ：刘景凯 刘世琦 冯磊 陈祥伟 薛小艳 成波 王越 李贺
期 刊 ：植物营养与肥料学报 2014年 20卷 4期 页码：989-997
Keywords:silicon, garlic seedling, quality, net photosynthetic rate, transpiration rate,
摘 要 ：【目的】大蒜是一种兼具营养价值和药用价值的蔬菜，由于品种退化、 土传病害严重等问题，导致大蒜植株矮小、 产量降低、 品质下降。硅作为一种公认的有益元素，在提高作物产量、 改善产品品质方面有非常重要的作用。但是关于硅对大蒜生长发育以及产量和品质的影响至今还没有相关报道，因此本试验研究了硅在青蒜苗生长和品质方面的作用，以期能为大蒜无土栽培优质高产提供一些理论参考。【方法】利用深液流水培方式，以“金乡白皮蒜”为试材，设置了5个硅水平（0、 0.75、 1.5、 2.25、 3.0 mmol/L）探讨了不同水平硅对青蒜苗生长、 光合特性及品质的影响。【结果】在0~1.5 mmol/L范围内，青蒜苗植株鲜重、 株高、 假茎长、 假茎粗以及色素含量均随硅浓度的增加而升高，当硅浓度高于1.5 mmol/L时，相关指标随其升高而降低，在硅浓度1.5 mmol/L时达到最大值； 同时叶片净光合速率（Pn）及气孔导度（Gs）也随营养液中硅水平的增加呈先升高后降低的趋势，硅浓度1.5 mmol/L时最高，比不施硅处理分别增加了32.41%和44.62%，而蒸腾速率（Tr）则恰好相反，随硅浓度增加先降低后升高，在Si1.5处理中最低，与对照相比降低了22.00%； 此外，叶片和假茎中可溶性糖、 游离氨基酸、 维生素C含量也随硅素水平的提高呈现出先升高后降低的趋势，硅浓度1.5 mmol/L时可溶性糖含量最高，与对照相比分别增加了25.37%~41.96%和21.28%~40.82%，维生素C和游离氨基酸含量则在Si2.25处理最高，但是Si2.25处理与Si1.5处理相比无显著差异； 硅浓度1.5 mmol/L时显著降低了叶片中可溶性蛋白含量，但能提高其在假茎中的含量，与不施硅处理相比叶片中可溶性蛋白含量降低了15.76%~21.62%，假茎中则增加了32.85%~53.73%。【结论】营养液中加硅后，青蒜苗植株鲜重、 株高、 假茎长和假茎粗均有明显增加，且其促进作用在其生育后期比生育前期更显著。加硅还可增加大蒜叶片内色素含量，增强光合速率，显著增加青蒜苗内可溶性糖、 可溶性蛋白、 维生素C和游离氨基酸的含量，提高其营养品质。因此，在大蒜施肥中，适当增加硅肥，有可能克服大蒜品种退化、土传病害对大蒜的不利影响。
Abstract:【Objectives】The degeneration of variety and serious soil-born diseases are important inhibitors for garlic plant growth, lower yield and quality. As a beneficial element, silicon plays an important role in improving yield and product quality. A study was conducted to investigate the effects of silicon on the growth and quality of garlic seedlings.【Methods】In this study, garlic cultivar, Jinxiangbaipisuan, was taken as an experiment material and five different concentrations of silicon, 0, 0.75, 1.5, 2.25 and 3.0 mmol/L, were used to treat garlic plants, and the growth, photosynthetic characteristics and qualities of garlic seedlings were measured. 【Results】The plant fresh weight and height, pseudo stem length and diameter and pigment contents are increased with the increase of silicon concentration from 0 to 1.5 mmol/L, while these items is decreased when the silicon concentrations are from 1.5 to 3.0 mmol/L, and the photosynthetic parameter (Pn and Gs) shows a similar trend. In the treatment of 1.5 mmol/L Si contents, Pn and Gs are increased by 32.41% and 44.62% respectively. The transpiration rate are decreased firstly and then increased with the increase of silicon contents, the minimum value appeares under Si of 1.5 mmol/L, in which the transpiration is reduced by 22.00% compared with the control. The contents of soluble sugar, free amino acids and vitamin C are also increased first and then decreased. The contents of soluble sugar in leaves and pseudo stems are highest under the 1.5 mmol/L silicon content, and are improved by 25.37%-41.96% and 21.28%-40.82% higher than those with the control. The contents of free amino acids and vitamin C reach their maximum values under Si2.25, and there are no significant differences between Si2.25 and Si1.5. The content of soluble protein in leaves is reduced by 15.76%-21.62%, in pseudo stems is improved by 32.85%-53.73% when the silicon concentration is 1.5 mmol/L.【Conclusions】 Proper Si addition can significantly increase the plant fresh weight and height and the pseudo stem length and diameter, the promoting effect is more significant at later period. Adding Si increase the pigment contents and photosynthetic rate in leaves, the nutritional quality of garlic seedlings because of the significant increase of the contents of soluble sugar, free amino acids and vitamin C. Therefore proper Si fertilization will be effective way in the relief of soil\|bron diseases and the deterioration of cultivars.
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