Differences in Physiological Responses of Different Drought-tolerant Turnip Seedlings to Drought Stress and Rehydration
HE Miao
JIANG Yuanhao
MIN Haozhe
LIN Tao
WANG Duo
XUAN Zhengying
Abstract：In order to clarify the effects of drought stress and rehydration on the physiological characteristics of turnip seedlings[Huangqiamagu(B1):drought-resistant type;Qiamagu(B2):drought-sensitive type)],pot culture was used to control water.The relative conductivity,malondialdehyde(MDA),osmotic adjustment substances[soluble sugar(SS),soluble protein(SP),proline(Pro),reducing sugar],antioxidant enzymes[superoxide dismutase(SOD),peroxidase(POD),catalase(CAT)],functional substances(total phenols,flavonoids,anthocyanins)and endogenous hormones[auxin(IAA),abscisic acid(ABA),trans-zeatin nucleoside(ZR),gibberellin(GA3)]of leaves after mild drought stress and severe drought stress and rehydration were studied.The results showed that with the increase of drought degree,the relative conductivity and MDA content of leaves of two turnip seedlings increased gradually,while the increase of B1 was smaller.Under drought stress,the contents of Pro and SS in the leaves of B1 and B2 germplasm seedlings increased gradually,the content of reducing sugar increased first and then decreased,the content of SP in B1 germplasm increased first and then decreased,and B2 increased gradually.The activities of SOD and POD in leaves of B1 and B2 germplasm seedlings were in direct proportion to the degree of drought stress,with the maximum value of CAT in B1 under severe drought stress and the maximum value of CAT in B2 under mild drought stress.The contents of total phenols and flavonoids in leaves of B1 and B2 germplasm seedlings increased gradually.The anthocyanin content of B1 increased gradually,while B2 increased first and then decreased.And the change range of B2 indexes in each treatment was larger than that of B1.With the increase of drought degree,IAA,ABA and ZR increased first and then decreased,while GA3 decreased gradually,and the contents of IAA,ZR and GA3 in B1 were lower than those in B2.After rehydration,the contents of all physiological indexes recovered except POD of B2.To sum up,drought and rehydration have different effects on the physiological characteristics of leaves of different drought-resistant turnip germplasms.Under drought stress,drought-resistant germplasm is less affected and shows stronger drought adaptability and resilience.
Keywords：Turnip seedlingsDrought stressRehydrationPhysiological characteristics
Publication Date：2025-02-15
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 116-123 )