EFFECT OF SEASONAL WEATHER CONDITIONS OF SAUDI ARABIA ON THE PERFORMANCE AND GROWTH OF EIGHT CULTIVARS OF TURFGRASS

摘要

Eight cultivars of warm season turfgrasses were evaluated for their growth and performanceunder seasonal weather conditions of Saudi Arabia and the results were compared with theirgrowth in controlled conditions in a greenhouse. Selected cultivars belonged to the major categories of turfgrass, i.e. Zoysiagrass, Bermudagrass and St. Augustinegrass. The study wasconducted at Muzahmiya, where the field station of King Abdulaziz City for Science and Technology is situated. Experiments were designed in a randomised complete block design (RCBD)and the following growth parameters were evaluated monthly: coverage, colour, visual quality,fresh and dry matter production. Leaf samples collected in summer and winter were subjected tototal chlorophyll analysis to give values for total chlorophyll content. The Zoysiagrass, 'Miyako'performed well in the summer season, but its relative, 'Nagissa' burnt off. Under greenhouseconditions 'Nagissa' produced a significantly higher amount of biomass during summer butunder open conditions it suffered leaf-scorching. The cultivar 'Tifgreen' performed well throughout the year under both conditions, but during winter it showed leaf-scorching. St. Augustinegrassshowed desirable qualities during summer but during winter it showed leaf-area reduction,yellowing and leaf-scorching. The cultivar 'Tifway' showed a drastic reduction in the leaf-areaduring summer under open and greenhouse conditions. Among the cultivars a variant of 'Miyako'and St. Augustinegrass produced significantly lower amounts of chlorophyll content duringwinter under both conditions.The two local Bermudagrasses studied showed inconsistent responses to the climatic conditions and their overall quality was not suitable for turfgrass. Eventhough the local Bermudagrasses lacked the aesthetics required for lawn grass, tfceir compactrooting system and low maintenance made them suitable as ground cover and they may be usedas a soil binder for eroded areas.