Further observations on pollination and seed setting in lucerne
Dwyer, R.E.P.; Allman, S.L.
Agric Gaz New South Wales 43(2): 141-146
Although natural crossing occurs, the exact extent and the agencies involved are in doubt. The main tension in the flower is concentrated in the curved staminal column. A well-developed vascular system is formed in the wings of the flower petals. In the field, heat causes automatic tripping. Tripping is also achieved by dipping the flowers in alcohol. In the laboratory, under varying conditions of humidity, flowers tripped readily at 100-108 F.; this temp. is frequently exceeded in direct sunlight in summer. Pollen is scattered for a considerable distance following mechanical tripping. Wind probably increases this radius of spread. Pollen on the standards of untripped flowers germinated readily. Rain is unimportant for pollination, especially as excessive moisture inhibits pollen germination. Delayed tripping, with exposure of the anthers, was noted both in the open and under cages.