水培条件下CO_2与NH_4^+/NO_3^-配比对番茄幼苗生育的影响  

Effects of interactions between different NH_4^+/NO_3^- ratios and CO_2 enrichment on growth and development of tomato seedlings under hydroponic culture conditions

作　　者：李娟[1] 周健民[1] 

机构地区：[1]中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室,南京210008

出　　处：《农业工程学报》2006年第7期138-142,共5页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金重点项目(30230250)资助

摘　　要：升高CO2浓度能够促进作物的光合作用,提高作物的生物量和产量,但关于CO2与NH4+/NO3-比及其交互作用对作物影响的研究较少,为探索番茄幼苗生长发育对CO2浓度升高的响应是否对NH4+/NO3-配比有较强的依赖关系,本试验在营养液栽培条件下,以番茄(L y cop ersicun escu lentum M ill)为试材,研究正常大气CO2浓度(360μL/L)和倍增CO2浓度(720μL/L)与不同NH4+/NO3-配比的交互作用对番茄幼苗生长的影响。结果表明:CO2浓度升高提高了低NH4+/NO3-比例处理中番茄叶片的光合速率和水分利用率,提高幅度随NH4+/NO3-比例的降低而增强,光合速率增强最大达55%。在同一CO2浓度处理下净光合速率与水分利用率均随NH4+/NO3-比例的增加而显著降低。这说明CO2浓度升高对番茄幼苗生长发育的促进作用随NH4+/NO3-比例的降低而提高,但并没有减弱全NH4+-N处理中番茄幼苗的受毒害作用。综上所述,CO2浓度升高能提高植物生产的节水能力和水分生产力;水培条件下,NO3--N是最适合番茄幼苗生长发育的氮源,其它NH4+/NO3-比例对番茄幼苗的生长发育有一定的抑制作用,仅以NH4+-N作氮源则番茄幼苗很难生长。Increasing atmospheric CO2 concentrations is generally expected to enhance photosynthesis and growth of agricultural C3 vegetable crops and, as a result, substantially increase yields. However, little is known about the combined effect of elevated CO2 and N species on plant growth and development. A growth chamber experiment was conducted to determine the influence of NH4^＋/NO3^- ratio and elevated CO2 concentrations on the growth and development of tomato seedlings. Tomato （Lycopersicon esculentum Mill var. Hezuo 906） was grown for 45 days in pots with nutrient solutions varying in NH4^＋ ： NO3 （%） ratio （100 ： 0, 75 ： 25, 50 ： 50, 25 ： 75, 0 ： 100） in growth chambers with ambient（360 μL/L） or elevated CO2 concentrations （720 μL/L）. Elevated CO2 increased photosynthetic rate and water use efficiency of tomato seedlings in all NH4^＋/NO3^- ratios in nutrient solution except ammonium-fed plants. Photosynthetic rate and water use efficiency of tomato seedlings were increased in the elevated CO2 treatment with increasing proportion of NO3^- in nutrient solutions and and photosynthetic rate were up to 55% higher at elevated than at ambient CO2 concentration. At both CO2 levels, the photosynthetic rate and water use efficiency of the plants increased as increasing proportion of NO3^- in the nutrient solutions. The resuits indicate that tomato seedlings may benefit more from CO2 enrichment when increasing proportion of NO3^- in nutrient solutions is supplied, and elevated CO2 does not inhibit the adverse effects on tomato seedlings when 100% NH4^＋-N in nutrient solution is supplied. In all, elevated CO2 concentration increased water saving on agricultural production and water productivity and at two CO2 levels, NO3^- N was the most suitable N source to tomato seedling growth, when other NH4^＋/NO3^- ratio was supplied, the growth of tomato seedling was inhibited to some extent. When the N source supplied as solely NH4^＋-N, tomato seedling was hard to grow normally.

关 键 词：CO2浓度升高 番茄 硝酸还原酶 可溶性蛋白质含量 生理生化指标 

分 类 号：S641.2[农业科学—蔬菜学]