氮形态对3种叶色生菜光谱吸收及产量品质的影响

Spectral Absorbance,Yield and Quality Responses of Three Leaf-color Lettuces to Various Nitrogen Forms Supply

采用玻璃温室水培盆栽的方法,研究了2种氮形态,即10 mmol/L硝态氮(N10)和5 mmol/L硝态氮与5 mmol/L铵态氮结合(N5+A5),对3种叶色生菜叶片光谱吸收及产量与品质的影响。氮形态与生菜叶色均影响了叶片光合色素的光谱吸收值,但不影响光谱吸收曲线变化趋势。与N5+A5处理相比,N10处理下3种叶色生菜光吸收峰值波长处的吸光度增加,同时3种叶色生菜叶片的光合色素含量大都有增加,但地上部鲜质量、地上部干质量显著降低。且不同叶色生菜生物量受氮形态影响程度不同,绿叶生菜地上部鲜质量降低幅度最大。氮形态处理对3种生菜叶片的类黄酮和花青素含量无显著影响。N10处理下,绿叶生菜和红叶生菜的总酚含量略高于N5+A5处理,绿叶生菜抗坏血酸含量则显著高于N5+A5处理。以上结果表明,氮形态对3种生菜光吸收特性和产量存在显著影响,且不同品种蔬菜影响程度不同。针对不同叶色生菜,调节氮供给形态和光环境,是提高不同叶色生菜产量和品质的可能途径。

The effect differences of nitrogen forms,10 mmol/L nitrate nitrogen(N10)and 5 mmol/L nitrate ni-trogen combined with 5 mmol/L ammonium nitrogen(N5 +A5),on spectral absorbance,yield and quality responses of three leaf-color lettuces.The results showed that spectral absorbance was influenced by nitrogen form and the cul-tivars of lettuce.The spectral absorbance was greatly increased under N10 treatment compared with N5 +A5 treat-ment.However,the chang trend of spectral absorbance curves of three leaf-color lettuces was not distinctly effected by nitrogen form.The contents of photosynthetic pigment were strikingly promoted when supplied with N10.On the contrary,significant decreases were found in shoot fresh weight,shoot dry weight and root cap ratio under N10 treat-ment.There was no remarkable difference in contents of flavonoid and anthocyanin between the two nitrogen form treatments.However,the total phenols contents of green lettuce and red lettuce were slightly improved when supplied with N10.And the ascorbic acid content of green lettuce was prominently enhanced by N10 treatment.These results indicated that nitrate nitrogen remarkably influenced the spectral absorbance and yield of three leaf-color lettuces, and the effects differed between cultivars.Regulating nitrogen form and light environment based on different color lettuce was a feasible approach to promote the yield and quality of different color lettuce.