不同施氮水平对“民乐紫皮”大蒜光合特性与叶绿素含量及品质的影响

Effect of Different Nitrogen Levels on Photosynthesis Characteristics,Chlorophyll Content and Quality of Allium sativum L.‘Minlezipi'

为了探讨不同施氮水平对大蒜光合作用及品质特征的影响,以"民乐紫皮"大蒜为试材,采用盆栽试验,研究了4种施氮水平下其光合特性参数、叶绿素含量和品质指标的变化。结果表明:在0~240kg/hm^2施氮水平范围内,随施氮量的增加,大蒜叶片叶绿素含量、净光合速率、气孔导度、胞间CO_2浓度及蒸腾速率随施氮量的增加而升高,至施氮量240kg/hm^2时达最高,其后降低。大蒜鳞茎品质指标大蒜素以240kg/hm^2氮处理最高,除6g/盆施氮处理以外分别比不施氮处理增加3.98%、4.56%和6.82%。说明增施一定的氮肥能显著提高大蒜的光合特性和叶绿素含量,改善光合性能,最终影响到大蒜的品质。所有处理中以240kg/hm^2对叶片净光合速率、叶绿素含量和大蒜素的效果最佳,表明240kg/hm^2的施氮量更有助于降低大蒜的蒸腾作用,提高叶片的叶绿素含量、光合速率和水分利用效率,并获得较高的大蒜品质。

In order to investigate the effects of different nitrogen levels on photosynthesis and quality characteristics of garlic,the Allium sativum L.‘Minlezipi＇was used as test material,using of pot experiment to study under 4kinds of nitrogen levels of photosynthetic parameters,chlorophyll content and quality indicators change.The results showed that the chlorophyll content,net photosynthetic rate（Pn）,stomatal conductance（Gs）,intercellular CO2concentration（Ci）andtranspiration rate（E）were increased in nitrogen rate range of 0-240kg/hm2.The parameters were the highest at level of 240kg/hm2 nitrogen application and then reduced.The highest of garlic allicin was 240kg/hm2 nitrogen supply.Except 6g/pot N treatment,nitrogen treatment increased 3.98%,4.56% and 6.82%,respectively.It was said that adding some N fertilizer could significantly improve photosynthetic characteristics and content of chlorophyll of garlic,the photosynthetic performance improvement,and ultimately affect the quality of garlic.The 240kg/hm2 treatment was the best on leaf net photosynthetic rate,chlorophyll content and allicin at all treatments.The 240kg/hm2 treatment increased the chlorophyll content,photosynthetic rate andtranspiration rate,and obtain a higher of garlic quality.