ECOLOGICAL ADAPTATION IN LOLIUM - MORPHOLOGICAL AND PHYSIOLOGICAL-PARAMETERS AT EARLY STAGES OF GROWTH IN 2 VARIETIES WITH DIFFERENT DEGREE OF PERSISTENCE

Two differently adapted varieties of L. perenne L., characterized by contrasting level of persistence in the Mediterranean environment, were evaluated during the initial period of plant growth for some physiological and morphological traits. No differences were observed when plants were grown at 20.degree. C. At 10.degree. C, the temperature of spring growth, the 2 cultivars differed in root and shoot development and water soluble carbohydrate content, while at 30.degree. C, the temperature characterizing the summer stress period, they differed in CO2 uptake and specific leaf weight. The results are discussed in relation to the role of the differences in the early stage of plant growth on persistence of the 2 varieties.