低浓度NaCl对水培韭菜生长、产量及品质的影响

摘要

NaCl 一直以来被认为是一个胁迫因子,且是造成植物盐害的主要因素,而低浓度 NaCl 对植物生长不仅没有危害,反而具有促进植物生长,提高品质的作用。韭菜营养液水培作为一种新型的栽培方式,很好的解决了韭蛆等病虫的为害。为了探究低浓度NaCl添加到营养液中对韭菜生长、品质和产量的影响,试验设定了0 mmol·L−1(对照)、5 mmol·L−1、10 mmol·L−1、20 mmol·L−1、30 mmol·L−15个NaCl浓度,研究不同浓度NaCl处理下韭菜生长、生理和产量的变化。研究结果表明,韭菜的株高、假茎粗和叶长均以20 mmol·L−1 NaCl处理下最高,各处理的叶片数均多于对照,叶片宽度随着 NaCl 浓度的增加呈现下降趋势。低浓度 NaCl 增加了韭菜的光合色素含量,10 mmol·L−1处理下叶绿素a、叶绿素b、类胡萝卜素和叶绿素a+b含量最高。NaCl处理能有效降低韭菜中硝酸盐的积累,各NaCl处理硝酸盐含量分别比对照下降12.42%、13.17%、15.16%和26.76%。Vc 含量随添加 NaCl 浓度的增加表现出先上升后下降的趋势,其中各 NaCl 处理含量分别比对照高12.2%、12.8%、5.1%、−15.4%,可溶性糖与粗纤维均在10 mmol·L−1时达到最大值。产量以10 mmol·L−1处理最高,3茬产量及总产量分别比对照处理增加6.7%、6.6%、6.9%、6.7%。综合分析认为,韭菜营养液中添加10 mmol·L−1的NaCl,在促进韭菜生长,降低硝酸盐,改善品质和提高产量上综合表现最佳。%NaCl is always considered as a stress factor and as the main cause of salt stress in plants. However, it has been proved that low concentrations of NaCl have no harmful effect on plant growth. In fact, studies have shown that low concentrations of NaCl actually promote plant growth and quality. As a new mode of cultivation, hydroponic culture has been a suitable solution to control Chinese chive diseases caused by Chinese chive maggot. To explore the effect of low concentrations of NaCl on the growth, quality and production of Chinese chive, 0 mmol·L−1 (CK), 5 mmol·L−1, 10 mmol·L−1, 20 mmol·L−1 and 30 mmol·L−1 NaCl were respectively added to nutrient solutions in the experiment. The results showed that plant height, pseudo-stem diameter and leaf length were highest under 20 mmol·L−1 NaCl treatment. Leaf number of Chinese chive treated with NaCl increased compared with that of CK. However, leaf width decreased with increasing concentration of NaCl. The contents of photosynthetic pigments increased after treated with low concentrations of NaCl. Chlorophyll a, chlorophyll b, carotenoid and chlorophyll a+b contents were highest under 10 mmol·L−1 NaCl treatment. NaCl treatment decreased nitrate accumulation and nitrate content decreased by 12.42%, 13.17%, 15.16%and 26.76%respectively under 5 mmol·L−1, 10 mmol·L−1, 20 mmol·L−1 and 30 mmol·L−1 NaCl treatments compared with that under CK. Vitamin C content increased by 12.2%, 12.8%and 5.1%and−15.4%under 5 mmol·L−1, 10 mmol·L−1, 20 mmol·L−1 and 30 mmol·L−1 NaCl, respectively, compared with that of the control. The contents of soluble sugar, crude fibers and yield of Chinese chive were highest under 10 mmol·L−1 NaCl. Yield increased respectively by 6.7%, 6.6%, 6.9%and 6.7%in the first harvest, second harvest, third harvest and 3 combined harvests under 10 mmol·L−1 NaCl over CK. Comprehensive analysis showed that adding 10 mmol·L−1 NaCl to nutrient solution enhanced growth performance, decreased nitrate content, improved quality and increased production of Chinese chives.