机械拨动幅度与持续时间对甘蓝幼苗生长及生理生化指标的影响OA

[Objective]The response characteristics of cabbage(Brassica oleracea var.capitata L.)seedlings to different intensities and durations of mechanical vibration were investigated,to screen the optimal vibration intensity that effectively controls excessive growth and cultivates strong seedlings,to provide theoretical basis and technical support for factory seedling culture.[Method]A self-propelled mechanical vibrator was tested on cabbage line'Shengan 15'by two-factor factorial design,which came up with 9 treatments based on 3 levels of vibration intensity and duration,namely T1(inclination angle of 0°-20° for 5 d),T2(20°-40° for 5 d),T3(40°-60° for 5 d),T4(0°-20° for 10 d),T5(20°-40° for 10 d),T6(40°-60° for 10 d),T7(0°-20° for 15 d),T8(20°-40° for 15 d)and T9(40°-60° for 15 d),as well as a group without vibration as control(CK).Based on measurements of growth-related indicators,principal component membership function analysis was performed to screen the optimal vibration intensi-ty that was contributed to strong seedlings.[Result](1)The plant height and hypocotyl length of seedlings were significantly re-duced after most vibration treatments compared to CK except for T1 and T2;stem diameter,root/shoot ratio and vigor index of seed-lings were significantly higher under T4-T7 than those of CK.(2)Total root length,root volume,total root surface area and root ac-tivity of seedlings under T4-T7 were significantly increased compared to CK.Except for T3,T8 and T9,the substrate disintegration rates under most treatments were slightly lower but not significantly different from CK.(3)Except for T9,the variable fluorescence(Fv),maximum fluorescence(Fm),potential photochemical efficiency of PS Ⅱ(Fv/Fo)and maximal photochemical efficiency of PS Ⅱ(Fv/Fm)in most treatments were significantly higher than those in CK;the non-photochemical quenching(NPQ)in all the treatments receiving mechanical vibration were significantly lower than that in CK.(4)The activities of catalase(CAT),peroxidase(POD)and superoxide dismutase(SOD),as well as the soluble protein content of seedlings under T4-T9 were significantly higher than those of CK,while the malondialdehyde(MDA)content was significantly lower.(5)Except for T1 and T9,the hardness of seedling epicotyl and hypocotyl was significantly higher under most treatments.(6)The principal component membership function a-nalysis indicated that T6 had the highest value.[Conclusion]Inclination angle of 40°-60° and vibrating for 10 d were considered the most suitable treatment for cabbage seedlings,with effectively controlled growth and stronger seedlings which were more suitable for mechanical transplantation.