Effects Of Buffalograss Seeds Soaking With Exogenous Hormones On Germination And Seedling Growth And Physiology

Buffalograss(Buchloe dactyloides)is the plant of Herbaceae Eragrostis subfamily.Buffalograss had many excellent characteristics,such as its low height,leaves in beautiful color,soft and tidy texture,adaptability,especially its strong resistance to drought,adaptability to maintain management and resistance to cutting.However,the germination rate was low due to the mechanical restraint of the uptake of the seeds and the internal factors of the seeds,so that the seeds were dormant and the germination rate was low.If measures were not taken to break the dormancy,even under appropriate conditions,only a few seeds would germinate.In addition,the baffulograss seedlings grow slowly,combined with irregular germination will easily lead to weed invasion and failure to form turf after sowing.Thus,the study on breaking dormancy of buffalo grass seeds and promoting the seedling growth makes sense.We studied the effects of exogenous hormones on dormancy and seedling growth and physiology of the seeds of buffalograss by soaking the seeds with different concentrations of gibberellin,auxin and abscisic acid.The main research conclusions were summarized as follows:(1)The study on effects of exogenous hormones soaking seeds on the seed germination of buffalo grass found that 1500 mg/L of gibberellin could significantly break the seed dormancy,improve its germination ability,accelerate its germination rate,raising the germination energy from 37.63% to 68.56% and the germination rate from 54.15% to 73.28% and enhance its seed vigor.Soaking seeds with 450 mg/L of auxin could enhance its seed vigor.Soaking seeds with abscisic acid could significantly inhibited the germination of the seeds.And the effect of gibberellin on the germination and seed vigor was better than that of auxin.Thus,1500 mg/L of gibberellin works best to promote buffalo grass seed to germinate and form turf.(2)The effects of exogenous hormones soaking seeds on the growth of buffalo grass seedlings were studied.Results showed that 2000 mg/L of gibberellin had a significant effect on the growth of aerial part in the early stage of seedling growth.450 mg/L of auxin had a weaker effect on the growth of aerial part of buffalo grass than that of gibberellin,but it had a significant effect in promoting the growth of its under-ground part.During the early period of seedling growth,250-450 mg/L of abscisic acid inhibited the growth of the aerial part;during the later period,it promoted its growth.Thus,2000 mg/L of gibberellin can be used to promote the growth of buffalo grass aboveground part and 450 mg/L of auxin can be used to enhance the root growth of buffalo grass to strengthen the seedling and prevent other weeds from invading.(3)The effects of exogenous hormones soaking seeds on the physiology of buffalo grass seedlings were studied.The results showed that with the growth and development of bison grass seedlings,the contents of non-structural carbohydrate and endogenous hormones increased first and then decreased with seeds soaking with the three kinds of hormones.Hormone soaking may enhance the carbon metabolism of seedlings by regulating the content of endogenous hormones.The hormones used in this study has a certain inhibitory effect on the soluble protein of buffalo grass seedlings.(4)The effects of exogenous hormones soaking seeds on the growth of buffalo grass mature seedlings were studied.The results showed that 1000 mg/L of gibberellin could increase the nonstructural carbohydrate and endogenous hormones.350 mg/Lof auxin and 100 mg/L ofabscisic acid had certain dwarfing effect on the mature seedlings and couldincrease the content of soluble protein and endogenous abscisic acid and increase its resistance.In summary,1500 mg/L of gibberellin or 450 mg/L ofauxin soaking seeds could significantly promote the germination force and seed vigor of buffalo grass.250 mg/L of abscisic acid soaking seeds could significantly inhibit the germination ability of buffalo grass.While the three kinds of hormones could all significantly promote the growth rate and the intensity of the physiological activities during the development of baffulo grass seedlings and have little effect on that of baffulo grass mature seedlings.This paper provided experimental basis for understanding the effects of exogenous hormones soaking seeds in improving germination uniformity and the germination ability and promoting the growth and physiology of the seedlings,theoretical basis for the rational use of plant hormones to promote seed germination and seedling growth and important reference value for buffalo grass to form turf...