INFLUENCE OF PARENT AND TEMPERATURE DURING POLLINATION ON ALFALFA SEED WEIGHT AND NUMBER OF SEEDS PER POD

Alfalfa seed weight and number of seeds per pod are important characte ristics which have been associated with seed yield and seed quality. T he objective of this research was to investigate the relative influenc e of seed and pollen parents and temperature during pollination on ind ividual seed weight and number of seeds per pod. The relative influenc e of seed position in the pod on seed weight was also investigated. Tw elve diverse clones were designated as seed (4) and pollen (8) parents . They were grown in the greenhouse at 24/18 day/night temperature and then transferred to growth chambers which were maintained at either 1 8 or 27 degrees C during and 24 h after pollination. Seed weight and n umber of seeds per pod were influenced by temperature during pollinati on, and also by both seed and pollen parents. The position of the seed in the pod influenced seed weight. The largest seed occurred at the b ase of the pod, which may have resulted from a differential nutrient s upply from the base to the top of the pod. The number of seeds per pod was greatest at 27 degrees C. This was attributed to enhanced pollen fertility and fertilization success at the higher temperature. Both se ed and pollen parents influenced seed weight and number of seeds per p od, and there were significant seed x pollen parent interactions for b oth traits. Environmental influence and pod position effects on seed w eight and number of seeds per pod were small when compared with geneti c effects. Selection for seed characteristics in seed and pollen paren ts could improve alfalfa seed production and seed quality.