Variation in Phalaris tuberosa L.

Abstract

Variation in the performance, morphology, and nitrogen content of lines of Phalaris tubevosa introduced from the Mediterranean region and of the Australian commercial line was examined. Regional differences existed in culm height, date of anthesis, seed weight, and nitrogen content of tops, but not in chromosome number.

Comparison of six lines, one each from Australia, Morocco, Algeria, Turkey, Israel, and Greece, grown at four different temperatures, established the high sensitivity of the Israeli line to high temperatures, and the vigour of the Israeli and Moroccan lines under low temperatures. The Algerian line showed some sensitivity to high temperatures also, but generally lines other than the Israeli responded similarly to increasing temperature. Regional differences in yield, apical dominance (reflected in tiller number and ratio wt. primary shoot/wt. tops), and leaf size and shape were obtained under each of four temperature regimes in a second experiment involving 55 lines.

In a field experiment, herbage yields from a Moroccan, an Algerian, and an Israeli line were compared with that of the Australian line grown in swards with Trifolium subterraneum and cut at intervals over 1 year. Lines differed in their response, but the introduced lines were no better than the Australian line.

The results are discussed in relation to the agronomic utilization of P. tuberosa, the possible geographical origin of the Australian line, and the question as to how far results from glasshouse experiments have predictive value in field experiments.