Growth of United States versus New Zealand white clover cultivars in diverse grasses in Mississippi, USA

The use of plant material outside the country of development is common, but whether such material is superior to existing types of the same species is questionable. Seven United States and eight New Zealand white clover (Trif olium repens) cultivars, germplasms, or breeding populations were evaluated for plant spread and dry matter yield for two years at Mississippi State, Mississippi, USA, when grown in monoculture or with grasses having differin g seasonal growth patterns, viz tall fescue (Festuca arundinacea) and bermu dagrass (Cynodon dactylon). Plant material originating in the United States had 49-53% greater plant spread and 79-222% greater clover dry matter yiel d in monoculture or in association with either grass than the New Zealand m aterial. Osceola, SRVR, and Brown Loam Syn#2 white clover had greater plant spread than all New Zealand material at 9 of 11 sampling dates. White clov er spread and yield under monoculture showed a closer correlation with grow th in association with common bermudagrass thin with tall fescue. White clo ver should be selected in the climate and with the grass association in whi ch it is to be utilised.