NO3^--N与NH4^＋-N配比对热带地区水培荆芥生长和品质的影响

Effects of different NO_3^--N/ NH_4^+-N ratios on the development and quality of the hydroponic Schizonepeta tenuifolia briq in tropics

探明热带地区秋冬季水培荆芥营养液配方中的NO3--N与NH4+-N的合理配比,为水培荆芥的氮素养分管理提供理论依据。该研究以华南农业大学叶菜B配方为基础配方,设计营养液中NO3--N与NH4+-N的5个不同配比即NO3--N∶NH4+-N=5∶5、6∶4、7∶3、8∶2和10∶0,分析不同硝态氮与铵态氮配比处理荆芥的产量、品质和生理指标。结果显示:不同NO3--N与NH4+-N配比对水培荆芥的生长和品质有着显著的影响:NO3--N∶NH4+-N为6∶4和7∶3时,植株生物量最大;增加营养液中NH4+-N的比例,可以显著提高荆芥叶片中叶绿素和类胡萝卜含量;NO3--N∶NH4+-N为7∶3时,荆芥根系活力和可溶性蛋白最高;NO3--N∶NH4+-N为8∶2时,荆芥的可溶性糖含量最高;NO3--N∶NH4+-N为7∶3时,荆芥的硝酸盐含量最低。综合各项指标,NO3--N与NH4+-N的配比为7∶3时对水培荆芥最适宜。

To seek the appropriate NO3--N and NH4＋-N ratios for the hydroponic Schizonepeta tenuifolia Briq in fall and winter in tropics,five ratios of NO3--N to NH4＋-N（5∶5,6∶4,7∶3,8∶2,10∶0,respectively） in the nutritient solution prepared on fomula B of South China Agricultural University were designed to study the effects of NO3--N to NH4＋-N ratios on its development and quality.At the NO3--N to NH4＋-N ratio of 7∶3,the biomass of the hydroponic Schizonepeta tenuifolia Briq was the largest,the root vitality and soluble protein were the highest,and the nitrate content was the lowest.At the NO3--N to NH4＋-N ratio of 6∶4,the biomass of the hydroponic Schizonepeta tenuifolia Briq was the largest as well.At the NO3--N to NH4＋-N ratio of 8∶2,hydroponic Schizonepeta tenuifolia Briq got the most soluble sugar content.The results suggested that the ratio of NO3--N to NH4＋-N set at 7∶3,would be best for the growth of Schizonepeta tenuifolia Briq.