腐殖酸钠对紫花苜蓿根系生长及生物量的影响

【目的】探索腐殖酸钠(SH)单施及其与磷肥(P)配施对紫花苜蓿根系生长的影响.【方法】采用盆栽试验,设6个SH施肥水平(SH,SH2,SH3,SH4,SH5,SH6)和2个磷肥施用水平(P1,P2),测定单株株高、单株地上及地下生物量、单株主根长、单株根表面积、单株根平均直径、单株根体积及根系活力.【结果】与对照(CK)相比,SH单施及其与P配施对紫花苜蓿主根长、根表面积、根平均直径、根体积、根系活力、地下生物量、株高及地上生物量均有显著地促进作用,且促进程度表现为SH-P1SH-P2SH;同时,紫花苜蓿地下根系性状与地上部性状呈极显著正相关(P0.01).在SH-P1处理组中,根系各形态指标、根系活力、株高及植株生物量随SH施用量的增加而增加,但当其增至一定程度(SH4或SH5)后开始呈下降趋势.综合分析可得,SH5-P1处理综合表现最好,且获得的地下生物量与地上生物量最高.【结论】试验肥效最佳的处理组合为SH5-P1,即腐殖酸钠为11.25g/盆,磷肥为3.41g/盆.

Effects of sodium humate on root growth and biomass of Medicago sativa

[Objective]In order to explore the effect of the single application of sodium humate (SH) and combined application with phosphorus (P)on root system of Medicago sativa.[Method]Pot experi-ment was conducted to measure plant weight,aboveground and underground biomass ,main root length, root surface area,average root diameter,root volume and root activity.[Result]The single application of SH and the combined application of SH-P had a significant promotion on root length,root surface area,av-erage root diameter,root volume,root activity,underground biomass,plant height and aboveground bio-mass of Medicago sativa,compared with the control (CK)and the promoting degree appeared in the de-creasing order of SH-P1 ,SH-P2 and SH.The root traits were significantly positively correlated with those of aboveground (P<0.01).Under the fertilizer combination of SH-P1 ,root morphological indexes,root ac-tivity,plant height and plant biomass increased as the increasing of SH application amount and showed a declining trend when SH rose from SH1 to SH4 or SH5 .Integrated analysis indicated that SH5-P1 treatment was the best with the highest aboveground and underground biomass.[Conclusion]SH5-P1 is the optimal fertilizer combination,including sodium humate 11.25 g and phosphorus 3.41 g per pot.