Effects of salt stress on the growth of Platycodon grandiflorus seedlings and the number of soil microorganisms in the rhizosphere
OBJECTIVE To study the effects of salt stress on growth and development of Platycodon grandiflorus seedlings and rhizosphere soil microbial quantity.METHODS Two-year-old potted P.grandiflorus seedlings were used as test materials,seedling height,root length,fresh and dry weight of shoot and underground part 200,400,600 mmol·L-1 salt),and the amount of microorganism in rhizosphere soil of P.grandiflorus was determined under 10,20,30,and 45 d treatments.RESULTS Salt stress inhibited the growth and development of P.grandiflorus seedlings.With the increase of salt stress concentration,the seedling height,root length,fresh and dry weight of P.grandifloras seedlings decreased.The amount of fungi in rhizosphere soil of P.grandiflorus seedlings increased first and then decreased with the increase of salt stress concentration and the extension of cultivation time,the number of bacteria and actinomycetes was on the rise.CONCLUSION The number of bacteria and actinomycetes in the rhizosphere soil of P.grandiflorus increases significantly with increasing salt stress concentration,suggesting that bacteria and actinomycetes may play a role in the adaptation of P.grandiflorus to salt stress.
Salt stressPlatycodon grandiflorusBiomassRhizosphere soilMicrobial quantityBacteriaFungiActinomycetes
NETL
NSTL
万方数据
