混合盐碱胁迫对普通田菁生物学特性的影响研究OA

To explore the effects of mixed salt-alkali stress on the growth and physiological characteristics of Sesbania cannabina,a sand-vermiculite mixed substrate experiment was conducted with five stress levels(CK,0.26%,0.52%,0.78%,1.04%).Growth,root traits,chlorophyll SPAD value,chlorophyll fluorescence parameters,and relative electrical conductivity were measured at 7,14,and 21 days after treatment.The results showed a low-concentration promotion and high-concentration inhibition pattern,with inhibitory effects intensifying with increasing stress level and duration.Under 0.26%stress,root morphological traits and aboveground dry weight increased significantly(P<0.05).Under 1.04%stress,growth parameters,root traits,Maximum photochemical efficiency(Fv/Fm),Actual photochemical quantum yield of PSII(Y(II)),Photochemical quenching coefficient(qP),SPAD value and relative electrical conductivity were significantly decreased,while Non-photochemical quenching coefficient(NPQ)increased significantly(P<0.05).In summary these results indicate that S.cannabina has certain adaptability to low-level mixed salt-alkali stress,while moderate to high-level stress damages its physiological functions in root architecture,photosynthetic system,and cell membrane stability.