EFFECT OF TASSEL INJURIES ON THE GRAIN-YI ELD AND QUALITY IN MAIZE

We have examined the role of mechanical stress (hail injury effect), h eat and drought stress effect - by weather - commonly in the hybrid co rn seedproduction, over three years. The role of weather as component of effects of physiological processes, and plant life processes - is v ery important - especially in the hybrid corn seed production. Our con clusions: The partial tassel injuries, do not cause big yield loss, in good years. The yield loss can be equal with the whole yield of poor years. The partial tassel injuries can cause 25-50% yield loss in aver age years. The stressing factors against the tassel caused huge damage s in bad years. The result with heat, and drought weather stressing ef fects can be the worst. The partial tassel injuries in this case can c ause eliminating the whole seed yield also. The breaking of the tassel branches (one of the treatments) had the most gentle damage effect. T reatment - removing of the tassel central spike - delays the starting of pollen shedding. Treatment - removing the tassel branches - can sho rten the pollen anthesis. The effect of tassel injuries: poor fertiliz ated reduced biological value seeds. The ratio of roundish fractions g rew. Because of the poor fertilization, the seeds maturity conditions are different. It depended on the seeds' position on the cob. The dama ge effect is growing after the harvesting, drying processes, and germi nation ability is deteriorating. These results are valid only to the c oncrete crossing combinations, place, and year. Because the parental l ines compatibility, the synchronization, and floration weather can be different.