摘 要：
通过水培试验研究不同氮处理(5 mmol·L~(-1)NO_3~--N、10 mmol·L~(-1)NO_3~--N和5 mmol·L~(-1)NO_3~--N+5 mmol·L~(-1)NH_4~+-N)对奶油生菜生长和生理特性的影响。研究结果表明,35 d后,总氮浓度相等时,NH_4~+-N抑制奶油生菜生长,该处理叶面积、株高、地上鲜重、地上干重、地下鲜重和地下干重分别降低78.2%、60.4%、87.0%、81.3%、80.1%和87.5%(P<0.05),此外,两者的生理活性如根系活力、可溶性蛋白质、超氧化物歧化酶活性和硝酸还原酶活性均有显著性差异(P<0.05)。与10 mmol·L~(-1)NO_3~--N(12.89 g)相比,5mmol·L~(-1)NO_3~--N(8.90 g)处理奶油生菜生物量稍微有所降低,叶面积、根长和地下干重分别降低48.1%、50.3%和37.5%(P<0.05),而叶可溶性糖含量和花青素相对含量分别升高67.5%和51.9%(P<0.05),而对NO_3~--N的吸收两者的比值在第21 d达到最大值,后者是前者的3.15倍。研究结果表明奶油生菜是喜硝蔬菜,且生菜的硝态氮适宜浓度前期(前21 d)为高浓度(10 mmol·L~(-1)),以便促进奶油生菜生长,后期(21 d后)可改为低浓度(5 mmol·L~(-1))以提高品质。
译 名：
Effects of different nitrogen on growth and physiological response of Lactuca sativa L. var. ramosa Hort with hydroponics in a plant factory
作 者：
ZHAO Yun-xia;YUAN Liu-huan;KONG Xiang-shi;TIAN Xing-jun;School of Life Sciences,Nanjing University;
单 位：
ZHAO Yun-xia%YUAN Liu-huan%KONG Xiang-shi%TIAN Xing-jun%School of Life Sciences,Nanjing University
关键词：
Lactuca sativa L.var.ramosa Hort;;nitrate nitrogen;;ammonium nitrogen;;physiological response
摘 要：
The effects of different nitrogen treatments( 5 mmol·L NO_3~--N,10 mmol·L~(-1) NO_3~--N,5 mmol·L~(-1) NO_3~--N +5 mmol·L~(-1) NH_4~+-N) on the growth and physiological characteristics of Lactuca sativa L. var. ramosa Hort were studied.The results showed that after 35 days,NH4+-N inhibited the growth of lettuce with the same nitrogen concentration. The leaf area,plant height,aboveground fresh weight,aboveground dry weight,underground fresh weight and underground dry weight decreased by 78. 2%,60. 4%,87. 0%,81. 3%,80. 1% and 87. 5% respectively( P < 0. 05). In addition,there were significant differences in their physiological activities such as root activity,soluble protein,superoxide dismutase activity and nitrate reductase activity( P < 0. 05). Compared with the treatment of 10 mmol·L~(-1) NO_3~--N( 12. 89 g),the biomass of lettuce reduced slightly with the treatment of 5 mmol·L~(-1) NO_3~--N( 8. 90 g),and the leaf area,root length and underground dry weight decreased by 48. 1 %,50. 3% and 37. 5% respectively( P < 0. 05),but the content of soluble sugar and anthocyanin increased by 67. 5% and 51. 9% respectively( P < 0. 05),while the ratio of NO_3~--N uptake reached the maximum on the 21 st day,which was 3. 15 times of the former. Our results showed that the creamy lettuce was a nitrate favorite vegetable,and the optimum concentration of nitrate nitrogen in lettuce was high( 10 mmol · L~(-1)) in early prophase( 21 days) in order to promote the growth of butter lettuce,but later( 21 days) low concentration( 5 mmol·L~(-1)) was better to improve quality.
