摘要
【目的】探讨不同氮浓度和品种差异对苗期薏苡生长和光合特性的影响,为阐明薏苡响应氮营养的机理及指导合理施氮提供理论依据。【方法】以皖薏1号和皖薏2号为材料进行水培试验,以NH4NO3为氮源,设4个氮水平(0、5、15和25 mmol/L)处理,处理后第4、8、12和16 d测定不同处理薏苡幼苗的地上部干重、根冠比、叶绿素含量、光合速率和叶绿素荧光参数。【结果】整个培养过程中,皖薏1号表现出茎细、叶窄、叶色偏浅,皖薏2号表现出茎粗、叶宽、叶色偏深,与皖薏1号相比,皖薏2号的株高相对偏低。2个皖薏品种5~25 mmol/L处理的地上部干重、叶绿素(a+b)含量、叶绿素a/b、净光合速率(Pn)、光系统Ⅱ最大光能转换效率(Fv/Fm)整体上高于0 mmol/L处理,而根冠比低于0 mmol/L处理。在整个培养过程中,皖薏1号的地上部干重随着氮浓度的增加逐渐增加,表现为0 mmol/L处理<5 mmol/L处理<15 mmol/L处理<25 mmol/L处理;皖薏2号的地上部干重随着氮浓度的增加呈先升高后降低的变化趋势,表现为0 mmol/L处理<5 mmol/L处理<25 mmol/L处理<15 mmol/L处理。不同培养时间下,5~25 mmol/L处理间的幼苗根冠比无显著差异(P>0.05,下同)。在0 mmol/L处理下,同一培养时间皖薏2号的地上干重和根冠比高于皖薏1号。2个品种除培养第4 d的叶绿素(a+b)含量为15 mmol/L处理最高外,其他培养时期的叶绿素(a+b)含量均随着氮浓度的增加而逐渐升高,且培养8~16 d时15和25 mmol/L处理的叶绿素(a+b)含量显著高于0 mmol/L处理(P<0.05,下同),相同条件下皖薏1号的叶绿素(a+b)含量均低于皖薏2号。皖薏1号5~25 mmol/L处理幼苗的Pn差异不显著,但均显著高于0 mmol/L处理;皖薏2号幼苗的Pn随着氮浓度的增加先升高后降低,均为15 mmol/L处理幼苗的Pn最高,且显著高于0 mmol/L处理。皖薏1号的Fv/Fm随着氮浓度的增加整体上呈升高趋势,皖薏2号的Fv/Fm随着氮浓度的增加呈先�
【Objective】In the present study,the effects of different nitrogen concentrations and varieties on seedling growth and photosynthetic physiology of different cultivars of coix were studied to provide theoretical basis for elucidating the mechanism of coix’s response to nitrogen nutrition and guiding rational nitrogen application.【Method】The hydroponic experiment was carried out with Wanyi 1 and Wanyi 2 as materials,NH4NO3 was used as the nitrogen source,and four nitrogen levels(0,5,15 and 25 mmol/L)were set.Coix seedling dry weight,root-shoot ratio,chlorophyll content,net photosynthetic rate and chlorophyll fluorescence parameters were determined at 4,8,12 and 16 d after treatment.【Result】During the entire cultivation process,Wanyi 1 showed thinner stems,narrower leaves,and lighter leaf color,and Wanyi 2 showed thicker stems,wider leaves,and darker leaf color.Compared with Wanyi 1,the plant height of Wanyi 2 was relatively lower.The above-ground dry weight,chlorophyll(a+b)content,chlorophyll a/b ratio,net photosynthetic rate(Pn),photosystem II maximum light energy conversion efficiency(Fv/Fm)of the two cultivars treated with 5-25 mmol/L nitrogen were generally higher than those under 0 mmol/L treatment,while the root-shoot ratio was lower than those under 0 mmol/L.During the entire cultivation process,the dry weight of the shoots of Wanyi 1 gradually increased with the increase of nitrogen concentration,showing 0 mmol/L treatment<5 mmol/L treatment<15 mmol/L treatment<25 mmol/L treatment;the dry weight of the shoots of Wanyi 2 increased first and then decreased with the increase of nitrogen concentration,showing 0 mmol/L treatment<5 mmol/L treatment<25 mmol/L treatment<15 mmol/L treatment.There was no significant difference in seedling root-shoot ratio among 5-25 mmol/L nitrogen treatments under different culture time(P>0.05,the same below).Under 0 mmol/L nitrogen treatment,the above-ground dry weight and root-shoot ratio of Wanyi 2 were higher than those of Wanyi 1 at the same culture time.Except fo
作者
王红娟
於春
路献勇
江本利
胡积送
余黎明
朱加保
闫晓明
WANG Hong-juan;YU Chun;LU Xian-yong;JIANG Ben-li;HU Ji-song;YU Li-ming;ZHU Jia-bao;YAN Xiao-ming(Institute of Cotton Research,Anhui Academy of Agricultural Sciences,Hefei 230001,China;Anhui Hui Nong Ecological Food Co.,Ltd.,Chizhou,Anhui 245108,China)
出处
《南方农业学报》
CAS
CSCD
北大核心
2020年第8期1925-1931,共7页
Journal of Southern Agriculture
基金
安徽省重点研究和开发计划项目(1804a07020114)
安徽省科技重大专项(18030701181)。
关键词
氮浓度
薏苡
水培
幼苗生长
光合特性
nitrogen
coix
hydroponics
seedling growth
photosynthetic characteristics