Response To Light Intensity of Sun And Shade On Two Cool Season Turfgrass

Background: Obtaining superior performance of SupraNova and Lark C3 turfgrasses under shade conditions is a challenging task. Both durability and performance of turfgrass are significantly affected by shade. In particular, morphological and physiological adaptation to low light is critical for maintaining quality and overall performance in turfgrass plants. Results: The purpose of this study was to study the response of SupraNova and Lark turfgrass morphology and photo-physiological potential to shading. The plants of 'SupraNova' and 'Lark' were collected from the lawn plots of the Horticulture Research Center of Northeast Agricultural University of China for 2 years and treated with gradient shading 35.62% after 2 months of culture, normal light intensity 70.79 % and 93.45% with full sun as the contrast represented by CK for comparison. Lark showed TQ and TCI in shady stage compared with SupraNova. Lark showed strong resistance to MDA, H2O2, O2-, SOD, POD, CAT and AsA, indicating that the antioxidant system of C3 turfgrass at 35.6% shade level. Under 70.79% shade treatment, MDA, H2O2, O2-, SOD, POD, CAT and AsA of the two cultivars decreased the most, and the longer the shading time, the average daily growth of the two turfgrasses increased first and then decreased. Lark outperformed SupraNova throughout the shading treatment, with 70.79% and 93.45%, respectively. Lark showed increased Chl A and Chl (A/B) in response to different shading levels, while SupraNova had the highest concentrations of Chl B and total Chl. Chlorophyll fluorescence qP, ETR, and Fv/Fm decreased significantly when shaded at 93.45%;Conclusion: The results of this study proved that decrease was more significant in SupraNova than Lark, and shading caused more severe changes in leaf morphology and anatomical structure than Lark turfgrass has the highest negative tolerance than SupraNova turfgrass, which is due to the better photosynthetic product transport capacity of Lark plants. In its anatomical structure, and" vascular bundle sheath structure, which enables it to have higher photosynthetic efficiency to adapt to negative stress. SupraNova and Lark first increased and then decreased with the increase of shade degree