基质栽培中营养液浓度及硝铵比对番茄生长的影响

Effects of Nutrient Solution Concentration and Ratio of NO-N to NH-N on Tomato Growth in Soilless Culture

以番茄为试材,采用无机基质栽培的方法,研究了不同营养液浓度(氮浓度分别为3.2 mmol·L-1(T0.4)、5.6 mmol·L-1(T0.7)、8.0 mmol·L-1(T1)、16.0 mmol·L-1(T2)、24.0 mmol·L-1(T3))和硝铵配比(NO-3-N/NH+4-N=100/0(R100)、75/25(R75)、50/50(R50)、25/75(R25)、0/100(R0))对番茄苗期生长的影响。结果表明:营养液浓度和硝铵比对番茄株高和生物量的影响有显著的交互作用。在硝态氮占主导的情况下(R100和R75处理),T2处理番茄地上部生物量最大,较其它处理显著提高7.8%~62.2%。在T0.7与T1浓度下,R75处理较R100处理地上部生物量显著提高7.6%和13.6%。铵态氮含量占主导的R25和R0处理显著降低番茄株高和地上部生物量,降幅达19.6%~26.9%和17.8%~48.6%。总根长、根表面积和根系生物量随营养液浓度的升高而下降,在低浓度条件下(T0.4)完全硝态氮更有利于番茄根系的生长,R100处理根表面积、总根长和根系生物量较其它硝铵比处理显著提高23.7%~88.7%、22.2%~112.7%和5.0%~180.0%,T0.4处理根冠比较T1处理显著提高1.3~1.7倍。硝铵复配相较于单一氮源使SPAD值提高9.9%~13.2%。综上,苗期以壮根为主要目的的管理策略中,推荐营养液浓度EC值控制在0.6~1.4 mS·cm-1,含盐量控制在0.51‰~1.01‰;此时氮浓度为3.2~5.6 mmol·L-1,硝铵比推荐75/25。

Tomato was used as test material,a pot experiment was conducted to evaluate the effects of nutrient solution concentrations(the N content was 3.2 mmol·L-1(T0.4),5.6 mmol·L-1(T0.7),8.0 mmol·L-1(T1),16.0 mmol·L-1(T2),24.0 mmol·L-1(T3)) and nitrate-ammonium ratio(NO-3-N/NH+4-N=100/0(R100),75/25(R75),50/50(R50),25/75(R25),0/100(R0)) on tomato seedling growth in soilless culture.The results showed that there was a significant interaction between concentration and ratios of NO-3-N to NH+4-N on plant height and biomass of tomato.Aboveground biomass of tomato in T2 treatment was the largest,which was significantly increased by 7.8%-62.2% compared with other concentration treatments under the treatments of R100 and R75.In the concentrations treatments of T0.7 and T1,the aboveground biomass of R75 treatment significantly increased by 7.6%and 13.6%than R100 treatment.In the treatments of R25 and R0,which the NH+4-N content was higher than NO-3-N,tomato plant height significantly reduced by 19.6%to 26.9%,and aboveground biomass reduced by 17.8%to 48.6%than the treatment of R100.Total root length,root surface area and root biomass decreased with the increase of nutrient solution concentration.Under the lower concentration(T0.4)of nutrient solution,nitrate nitrogen was more beneficial to the growth of tomato roots,and root surface area,total root length and root biomass of R100 treatment were significantly increased by 23.7%-88.7%,22.2%-112.7% and 5.0%-180.0% compared with other ratio of nitrate to ammonium treatments.Root-shoot ratio of T0.4 treatment was significantly higher by 1.3-1.7 times than T1 treatment.The SPAD value in the treatment of combined addition of NO-3-N and NH+4-N increased by 9.9% to 13.2% than the alone addition of NO-3-N or NH+4-N.In general,in the stage of tomato seedling,the recommended nutrient solution concentration EC value was 0.6-1.4 mS·cm-1 and the salt content was 0.15‰ and 1.01‰,in which the N concentration was 3.2-5.6 mmol·L-1,and the suitable the ratio of nitrate to ammonium was 75/25,the recommended concentration and NO-3-N/NH+4-N ratio could enhance the growth of tomato roots.