SEED PRODUCTION QUALITY IN TRIFOLIUM-BALANSAE AND TRIFOLIUM-RESUPINATUM - THE EFFECT OF TEMPERATURE

Seed production is a crucial factor determining the survival of the sm allseeded annual pasture legumes Trifolium balansae and T. resupinatum , which are new to Australian farming systems. Work with other species suggests that temperature may be important in determining seed produc tion and quality. T. balansae cv. Paradana and T. resupinatum lines SA 12240, SA 14433 and cv. Kyambro plants were placed in a controlled en vironment at 18/13, 21/16, 24/19 and 30/25 degrees C when flowering st arted. Hardseededness and the formation of green and yellow seeds, as opposed to brown seeds in T. resupinatum, were positively related to t emperature. Seed weight was negatively related to temperature, but the effect of temperature on seed production was not clear. The level of seed production was higher in Paradana than in SA 12240, SA 14433 and Kyambro at all temperatures, due to a higher number of seeds per inflo rescence; the generic potential for seed production was greater in Par adana than in SA 12240 and SA 14433. Early inflorescences produced mor e numerous and heavier seeds with a higher hard seed content than late inflorescences; inflorescence maturity did not influence seed colour. Differences between early and late inflorescences from the field were similar.