Physiological differences in rooting and response to drought in shoots of female and male Torrey a grandis'Merrillii'
[Objective]This study,with an exploration of the rooting differences and the physiological differences in response to drought stress between male and female Torreya grandis'Merrillii',is aimed to provide a scientific basis for the cultivation of drought-resistant germplasm resources of T.grandis'Merrillii'.[Method]First,with the shoots of newborn male and female T.grandis'Merrillii'selected as materials,a comparison is conducted of the differences in rooting of summer cuttings between them.Then,PEG solution was applied to male and female T.grandis'Merrillii'with consistent rooting status for simulated drought treatment after which the changes of antioxidant enzyme activity,osmomodulating substances,membrane lipid peroxidation and reactive oxygen species content of male and female seedlings were compared and analyzed under different treatment times.[Result]The survival rate of male T.grandis'Merrillii'of summer cuttings was generally higher than female and the best time for cuttings was different for male and female T.grandis'Merrillii'.Cuttings for the female in June had higher survival,rooting rates and a higher number of lateral roots than those in July and August whereas the survival rate and rooting rate of male cuttings in August were higher than those in June and July,and the number of lateral roots was higher.When the male and female T.grandis'Merrillii'were cut for the same number of days,the survival rate and rooting rate of male plants were higher than the female ones.Drought stress caused significant changes in antioxidant enzyme activity in fragrant leaves,and disturbed its osmoregulatory function and reactive oxygen species metabolism balance.Under drought stress,female plants had higher superoxide dismutase(SOD)activity,peroxidase(POD)activity and catalase(CAT)activity,as well as lower malondialdehyde(MDA),proline(Pro),superoxide anion(O2-)and hydrogen peroxide(H2O2)than male strains.[Conclusion]The male T.grandis'Merrillii'of summer cuttings have a higher survival rate of cuttings than female,and under drought stress,the female T.grandis'Merrillii'can better use the antioxidant system to reduce the accumulation of reactive oxygen species and cell damage caused by drought stress.Thus,the female T.grandis'Merrillii'are more drought-tolerant than male ones.[Ch,4 fig.1 tab.28 ref.]
万方数据
维普
