Germination response of Phalaris paradoxa L. seed to different light qualities

The influence of different light regimes on the germination of Australian and English populations of Phalaris paradoxa L. (awned canary-grass) seed was investigated to determine the impact of changing tillage practices on weed infestation. Seeds of all biotypes were highly viable, but differed in levels of innate dormancy (26-99%). In one experiment seed from a single Australian biotype, either enclosed in the spikelet glumes or having the spikelet glumes removed, were exposed to nine light treatments. Germination was stimulated by red and white light, but was inhibited by far-red light. Time to 50%, germination was less for seed enclosed in the spikelet glumes than for naked caryopses, although the final percentage of seed germinating when still enclosed in the spikelet glumes was significantly lower than for naked caryopses. In another experiment, six Australian and English biotypes with varying dormancy characteristics were exposed to eight light treatments. Red light did not stimulate germination in the deeply dormant biotype, however stimulated all other biotypes. Germination in darkness was below 20% in all biotypes except for one where germination was 51%. To overcome dormancy seeds were imbibed and placed in darkness at 16degreesC for either 7 or 14 days prior to exposure to red or white light for a single 15-min period. Dormancy in all biotypes was overcome indicating that a period of burial may decrease the dormancy level and increase seed sensitivity to light. This increased light sensitivity suggests that exposure to light during tillage may stimulate germination in P. paradoxa seed.

Abstand, Ausbau, creativity and ludicity in Australian English

The social history of a language or variety, and its emergence, consolidation and stabiliza tion, allow us to combine the formal data of the language (principally its sound structure, grammar and lexis) with the external conditions in which they have evolved. The advance of Australian English in terms of its differentiation (Kloss's abstand) and elaboration of roles (Kloss's ausbau) pose problems of chronology, periodization, description and expla nation. This paper extends the conventional scope of abstand and ausbau to the analysis of the social history of Australian English. It argues that two factors are central to the emerging identification of Australian English: creativity, in the sense of morphological innovation, especially here in diminutives like reffo ('refugee') and pollie ('politician'); and in ludicity, defined as a deep-rooted playfulness with language. While these character istics are only part of the overall dynamics of the social history of Australian English, the evidence is sufficiently extensive to warrant further investigation. An earlier version of this paper was given at the Mitchell Symposium at Macquarie University on 26 April 2002 under the title ‘E pluribus plures? Diversity and integrity in Australian English’. I am grateful to members of the Symposium, and to two anonymous reviewers, for valuable comments and criticism