Effects Of Exogenous ASA And CAMP On The Primordium Of Pleurotus Ostreatus

Pleurotus ostreatus is an edible basidiomycete widely distributed all over the world.It has fat flesh,delicious taste,high nutritional value and medicinal value,and is the most widely cultivated edible fungus with the largest consumption in China.The primordium formation of Pleurotus ostreatus is crucial in its growth and development,but there have been few studies on its molecular mechanism.L-ascorbic acid(ASA)is a representative reductones in animals,plants and microorganisms.It is a multifunctional metabolite that not only directly removes active oxygen produced in living organisms,but it also has very important physiological functions.Cyclic adenosine monophosphate(cAMP),as a second messenger,has been found in both prokaryotic and eukaryotic cells and is capable of regulating the growth and development of organisms in response to a variety of extracellular stimuli.In this experiment,the effects of L-ascorbic acid(ASA)and cyclic adenosine monophosphate(cAMP)on the primordium formation of Pleurotus ostreatus were studied by exogenous application,and the possible pathways and mechanisms were discussed.The main conclusions of this paper are as follows:1.The effects of different culture medium on the primordium formation of Pleurotus ostreatus were measured,and the medium which was most favorable for the formation of Pleurotus ostreatus was selected for subsequent addition experiments.The results showed that the mycelial growth rate,mycelial protein content and mycelial dry weight of the SA medium were the lowest in the three mediums of YM,PDA and SA.Its nutrition is the most barren,but the time required for primordium formation is the shortest.It is most beneficial for the formation of the primordium of Pleurotus ostreatus.It is in line with the theory of nutrient depletion,and the SA medium is selected for subsequent exogenous addition experiments.2.The effect of the ASA on P.ostreatus primordia formation were measured.Results showed that:①When ASA concentration at 0.5-1.5mm can promote the growth of mycelia,high concentration ASA can inhibit the growth of mycelia.ASA significantly reduced mycelial protein content compared with the control group.When the ASA concentration was 1.5 mM,the mycelial protein content was the lowest.When the concentration of ASA was 1.5 mM,the primordium of Pleurotus ostreatus is formed fastest,and the primordium formation time was 14-18 days.Compared with the control group,the addition of ASA increased AAO activity in the early stage of mycelial growth,and then rapidly decreased before the primordium formation,and approached zero.②After the addition of ASA,the expression levels of fst3 decreased during the mycelial growth stage.The expression levels of Po.WC-2 and fst4 increased,the expression levels of Po.WC-1 decreased during the Primordium formation stage.③There is no double superposition effect on the expression of Po.WC-1 by ASA plus blue light treatment.The addition of ASA under blue light down-regulates the expression of Po.WC-1.If blue light up-regulates the expression of Po.WC-2,under blue light The addition of ASA reduced the expression of Po.WC-2.If the blue light was down-regulated or did not affect the expression of Po.WC-2,the addition of ASA under blue light increased the expression of Po.WC-2.3.The effect of the cAMP on P.ostreatus primordia formation were measured.Results showed that:①When cAMP concentration was 0.5-3mm,it could promote the growth of mycelia,and high concentration of cAMP inhibited the growth of mycelia.cAMP significantly reduced mycelial protein content compared to the control group.The mycelial protein content was the lowest when cAMP was added at a concentration of 1 mM.When the concentration of cAMP was 1 mM,the primordium of Pleurotus ostreatus formed fastest,and the primordium formation time was 15-19 days.②After the addition of cAMP,the expression levels of Pkacl decreased,the expression levels of Po.WC-2 and Pkac2 increased during the mycelial growth stage.The expression levels of Po.WC-1,fst3 and Pkacl decreased,the expression levels of Po.WC-2 and fst4 increased during the primordium formation stage.③There is no double superposition effect on the expression of Po.WC-1 by cAMP plus blue light treatment.The addition of cAMP under blue light down-regulates the expression of Po.WC-1.If the CK group blue light up-regulates the expression level of Po.WC-2,then the blue light of the cAMP treatment group down-regulates the expression level of Po.WC-2.If the blue light of the CK group does not up-regulate the expression level of Po.WC-2,then the blue light of the cAMP treatment group is up-regulated by Po.WC-2 expression level.