EFFECTS OF SEA WATER AND HERBICIDE FOR SALT TOELARNT WEED MANGEMENT IN TURFGRASS

Sea water in combination with trifloxysulfuron-sodium and quinclorac were used to observe weed injury level in turfgrass field. The weed species viz., Sporobolus diander (L.) R. Br., Croton aromaticus L., Croton rotundus and Emilia sonchifolia (L.) DC. ex Wight except Emilia atrovirens were fully controlled when treated with 3⁄4 recommended trifloxysulfuron-sodium with sea water, 3⁄4 recommended trifloxysulfuronsodium with 3⁄4 sea water, 1⁄2 recommended trifloxysulfuron-sodium with sea water, 3⁄4 recommended quinclorac with sea water and 3⁄4 recommended quinclorac with 3⁄4 sea water. Eragrostis atrovirens (Desf.) Trin. ex Steud. exposed maximum (48%) injury when treated with 3⁄4 recommended trifloxysulfuron-sodium and sea water. Paspalum vaginatum Sw. showed only 8% injury to sea water in combination with 3⁄4 recommended quinclorac, indicating greater salt tolerance among the three turfgrass. Zoysia japonica Steud. also exposed no more than 14% injury when treated with sea water in combination with 3⁄4 recommended trifloxysulfuron-sodium or quinclorac. Cynodon dactylon (L.) Pers. ‘‘Satiri’ had up to 21% salt injury with 3⁄4 sea water in combination with 3⁄4 recommended trifloxysulfuron-sodium. Introduction Weeds cause a continuous problem in management of all turfgrass species. There are numerous herbicides available for pre and post weed control in bermudagrass (Cynodon dactylon), seashore paspalum (Paspalum vaginatum) and zoysiagrass (Zoysia japonica) (Teuton et al. 2004). Seashore paspalum exhibits exceptional salt tolerance (Uddin et al. 2009, 2011a, 2012a) and also bermudagrass, is listed as tolerant (Carrow and Duncan 1998). Most herbicides used in warm season turfgrass can control grasses and sedges. Non-selective use of herbicides such as glyphosate and glufosinate, provides control but injures desired turf (Hossain et al. 1999). Quinclorac is also leveled in turfgrass preemergence and post emergence for control of several weed species including Digitaria sanguinalis, Panicum repens, Trifolium repens, and Hydrocotyle spp. (Kelly and Coats 1999). Trifloxysulfuron-sodium, a sulfonylurea herbicide, has been developed for use in cotton, sugarcane and bermudagrass (Mosdell et al. 2001, Porterfield et al. 2002). Trifloxysulfuron-sodium was readily absorbed by shoots and roots and was rapidly translocated in weeds. Growth of susceptible weeds was inhibited by trifloxysulfuronsodium application with complete mortality within 1 to 2 weeks after application (Hudetz et al. 2000). Several golf courses have the capability to use saltwater for irrigation, and this practice is becoming more common in coastal environments (Duncan and Carrow 2000). Many weeds can be suppressed in saline conditions but salt tolerant weeds will require other means of control. Weeds are a common problem and need to be controlled in order to maintain a high quality turf. *Author for correspondence: . Department of Crop Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia. Department of Agronomy, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh.