Effects of Shade Stress on Growth and Responsive Mechanisms of Bermudagrass (Cynodon dactylon L.)

Cynodon dactylon (L.) Pers. (bermudagrass) is a member of family Poaceae. It is a C-4 grass that grows extensively from both rhizomes and stolons, as well as by producing seeds. Due to its superior turf quality and outstanding durability, bermudagrass is widely used for residential and recreational areas worldwide. However, the grass is also considered as a troublesome weed in several crops mainly sugarcane (Saccharum officinarum), cotton (Gossypium hirsutum), maize (Zea mays), wheat (Triticum aestivum) and rice (Oryza sativa). It grows well in tropical and subtropical regions between 45 degrees N and 45 degrees S in more than 100 countries worldwide. Due to its ability to form a dense mat and fine textured appearance, bermudagrass is suitable for ornamental home lawns, golf course fairways/tees, athletic fields, industrial parks and soil erosion control as well. However, a major limitation to bermudagrass cultivation is susceptibility to shade stress. The shade come from trees in home lawns, shrubs or physical structures bring challenges for grass. Therefore, understanding how it adapts and grows well under shade is essential for the utilization and management of the important genetic resource of this species. Bermudagrass has been found to be moderately tolerant against shade because tolerance varies from genotype to genotype. It can tolerate shady conditions morphologically, physiologically, and anatomically by developing structural modifications (external/internal modifications), activating antioxidant enzymes and releasing primary/secondary metabolites. The objective of the current review is to better understand the growth and development of bermudagrass and its response mechanisms against shade stress.