Effects Of Several Biostimulants On The Activity Of SnRK1 And Salt Tolerance Of Strawberry

The sucrose non-fermenting-1-related protein kinase 1?SnRK1?plays central role in regulating carbon metabolism and energy balance in plant.Meanwhile,it can activate the defensive system of plant to copy with the high salt stress.2,1,3-Benzothiadiazole?BTH?,?-Aminobutyric acid?BABA?,Salicylic Acid?SA?and Harpin play an important role in plant growth and development and against stress.There is little research on the regulation between SnRK1 and biostimulants.Strawberry?Fragaria×ananassa?cultivar‘miao xiang 7'was used to investigate the effects of BTH,BABA,SA and Harpin with a different concentration on carbon metabolism,SnRK1 activity,the expression characteristics of 5genes which were downstream of the SnRK1 in one day and make sure the best concentration.Then we studied effects of 150 mg?L^-11 BTH,0.2mmol·L^-11 BABA,100?mol?L^-11 SA,1:1000 Harpin and their mixtures?on SnRK1 activity,the expression characteristics of 5 genes which were downstream of the SnRK1 and growth of strawberry plant in one month.Finally,we researched the effects of these biostimulants and their mitures on SnRK1activity and plant growth,in order to study the effects of 4 biostimulants on strawberry salt tolerance and the correlation with SnRK1.The main results are shown as follows:1.The exogenous spraying of BTH,BABA,SA and Harpin in different concentration on strawberry leaves could promote SnRK1 activity in 12 hour.150 mg?L^-11 BTH,0.2mmol?L^-1BABA,100?mol?L^-1SA and 1:1000 Harpin work best,SnRK1 activities are promoted24.04%,15.92%,22.48%,26.59%after 4 hour's treatments.BTH and Harpin have better effects than BABA and SA,and they still take effect at 12 h.4 biostimulants up-regulate the relative expression level of the genes down stream of SnRK1obviciously,especially,FaABCB related to the transporation of auxin and FaUDG related to sugar change are more sensitive to the biostimulants in 4 hour.Sprying of 4 biostimulants can effectively promote the net photosynthetic rates and the soluble sugar and starch contents in one day.2.The plant growth of strawberry seedings are better than the control after one month's treatments of 150 mg?L^-11 BTH,0.2mmol?L^-11 BABA,100?mol?L^-11 SA,1:1000 Harpin and mixture??150 mg?L^-11 BTH+0.2 mmol?L^-11 BABA+100?mol?L^-11 SA?and?(150 mg?L^-1BTH+0.2 mmol?L^-11 BABA+100?mol?L^-11 SA+1:1000 Harpin).SnRK1 activities change little after 4 day's treatments,but they are promoted a lot after the second sprying of these biostimulants at the 15 day,and the mixtures work better.Which indicates that 4biostimulants influence SnRK1 activity in a short time,and overlays of them work better.3.Compared to the control without salt stress,salt stress weken the plant growth,SnRK1activity,netphotosyntheticrates,chlorophyllfluorescence parameters,SPAD,CAT and SOD activities,increase O₂^-content,MDA content,increase Na⁺content and reduce K⁺content in strawberry leaves and roots.Sprying 150 mg?L^-1BTH,0.2mmol?L^-11 BABA,100?mol?L^-11 SA,1:1000 Harpin and mixture?and?before salt stress can increase the SPAD,net photosynthetic rates,?PS?and Fv/Fm,promote the ability of photo-assimilation to remit the hurt of salt on plant growth and reduce the death of cells;The exogenous biostimulants can promote CAT and SOD activities,reduce O₂^-and MDA content,rejust the cell solute potential to relieve the salt hurt;The exogenous biostimulants can increase the accumulation of K⁺and reduce the absorb of Na⁺,which indicate that the exogenous biostimulants remit the salt hurt by regulating the absorb and allocation of ions.From the point of the effects of these biostimulants,mixtures work better than the single.