摘要
在开顶式生长箱内,以黄瓜为试验材料,采用营养液培养方法,研究了不同氮、磷水平条件下大气CO2浓度对黄瓜植株矿质养分含量以及根系生长的影响。结果表明:黄瓜植株各部位N素含量随供氮水平提高而增加,磷水平提高也能促进各部位N含量的提高。植株各部位P含量随供磷水平的提高而升高,在相同磷水平下,缺氮会使各部位P含量升高。大气CO2浓度升高会使黄瓜植株各部位氮及特定部位的P含量降低。黄瓜根部的Ca含量随CO2浓度的升高而显著降低,氮和磷水平的升高极显著地增加其含量,且CO2浓度与供磷水平、供氮与供磷水平以及这三者之间存在明显的交互作用。供氮、供磷水平的升高极显著地提高了黄瓜叶片Ca的含量以及茎部Mg的含量,且两者存在明显的交互作用。黄瓜总根长和总根表面积随CO2浓度的增加有增大的趋势;在缺磷条件下,总根长和总根表面积随氮水平的提高而增大;而同一氮水平和CO2浓度下,磷水平的降低会增加总根长和总根表面积。总体看来,大气CO2浓度的升高能促进黄瓜根系的生长,但会使得黄瓜植株某些部位N、P、Ca、Mg等矿质元素含量降低,而供氮、供磷水平的提高可以通过增强黄瓜的生长与活力促进黄瓜根系对矿质养分的吸收,从而缓解由于CO2浓度升高带来的矿质元素含量降低的风险。由此,在对设施蔬菜CO2施肥的同时,也要注重适量提高合理配比下矿质元素的供应。
The effects of different combinations of atmospheric CO2 concentrations([CO2]),nitrogen(N)and phosphorus(P)levels on mineral nutrient concentrations and root growth of cucumber were studied by the nutrient solution culture method in the open-top chambers.Three[CO2]levels(400μmol/mol(CK,C1),625μmol/mol(C2),1200μmol/mol(C3)),three N levels(low N(N1),medium N(N2),high N(N3))and two P levels(low P(P1),medium P(P2))were designed.The results showed that N concentrations in all cucumber organs increased with the increase of N level,and N concentration in N3 treatment was significantly higher than those in N1 and N2 treatments.The increase of P level also promoted N concentrations in cucumber.P concentrations in all cucumber organs increased with P supply increasing.Under the condition of N deficiency(N1),P concentrations in all cucumber organs increased.Elevated[CO2]reduced N and P concentrations in specific organs of cucumber.Ca concentration in cucumber roots decreased significantly with the increase of[CO2],whereas higher N and P levels significantly increased Ca concentration.There were apparent interactions between the[CO2]and P level,N level and P level,and within these three factors on Ca concentration in cucumber roots.The rise of N and P levels also significantly increased Ca concentration in cucumber leaves and Mg concentration in cucumber stems,and there was a significant interaction between N and P levels.Total length and surface area of cucumber roots increased with the[CO2]increasing.Under the condition of P deficiency(P1),total length and surface area of cucumber roots increased with the increase of N level,whereas a decrease in P level caused the increase in total length and surface area of cucumber roots at the same N level and[CO2].In general,the increase of[CO2]can promote the growth of cucumber roots,but reduce the concentrations of mineral nutrient such as N,P,Ca and Mg in some organs of cucumber.However,the increase of N and P levels can promote the absorption of mineral nutrients in roots by enhancing the growth and vitality of cucumber,thereby can alleviate the risk of the decrease in mineral nutrient concentrations due to the elevated[CO2].The above results suggest that the applying suitable amount of mineral nutrients with matched proportion is quite necessary while CO2 fertilization is conducted to the greenhouse vegetables.
作者
陈雨娇
李汛
田兴军
段增强
CHEN Yujiao;LI Xun;TIAN Xingjun;DUAN Zengqiang(School of Life Science,Nanjing University,Nanjing 210023,China;State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China)
出处
《土壤》
CAS
CSCD
北大核心
2020年第6期1129-1138,共10页
Soils
基金
国家自然科学基金项目(41877103)
中科院战略性先导科技专项B类(XDB15030300)资助。
关键词
大气CO2浓度
氮水平
磷水平
矿质养分含量
根系生长
Atmospheric CO2 concentration
Nitrogen supply level
Phosphorus supply level
Mineral element concentrations
Root growth
