The Effects Of Carnosine And Chitosan On Drought Resistance Of Bermudagrass

Carnosine is a natural dipeptide with anti-oxidation,freeradicals,andanti-cell aging.It is not only an antioxidant additive in food,but also plays an important role in the pharmaceutical and healthcare industries,such as seed treatmentformulation,elicitor of plant disease,fertilizer and soil modifier,fruit and vegetable fresher.Drought seriously affects the growth and development of turf grass.Mild drought affects turf quality while severe drought results in the death of turf plant.Taking bermudagrass(Cynodon dactylon cv.'Tifway')as materials,the alleviation of leaf spraying carnosine and chitosan on drought stress was examined.The specific research contents and conclusions were as follows:In greenhouse,five concentrations of carnosine(2 mg/L,4 mg/L,6 mg/L,8 mg/L,10 mg/L)and chitosan(0.01%,0.03%,0.05%,0.07%,0.09%)were screened and the optimal concentrations of carnosine and chitosan for obvious mitigated effects on drought stress in bermudagrass were obtained.Results showed that the concentration of 10mg/L had the most significant alleviation for carnosine in bermudagrass,with more green leaves and higher TQ than other concentrations under 20 d of drought stress.Five concentrations of chitosan caused higher drought resistance than control treatment,but 0.03%was the most one with more green leaves and superior TQ than other four concentrations.In growth chamber,plants were sprayed carnosine and chitosan with their respective optimal concentration.The physiological and ecological mechanisms of carnosine and chitosan mitigated effects on drought stress in bermudagrass were analyzed through measuring turf quality,leaf relative water content,electrolyte leakage,chlorophyll content,antioxidant enzymes activity as well as peroxidation products.The results showed that,spraying withcamosine and chitosan under drought stress,significantly improved turf quantity and leaf relative water content,decreased electrolyte leakage,and increased leaf Ch1 content.Moreover,it enhancedactivities of CAT and POD,as well as decreased the contents of H2O2 and MDA.In summary,compared with only distilled water spray,spraying carnosine and chitosan both exogenous substances can improve the drought resistance of bermudagrass and delay turfgrass aging.