The purpose of this research was to investigate the influence of shade net and ventilation on the yield production ofonion seed in greenhouse. Two onion cultivars, ‘6701’ and ‘6704’, was used for this experiment, and grown in severalgreenhouses with different type of shade net percentages (0, 35, and 55%) and with or without ventilation. ‘6701’ and ‘6704’with parameter temperature showed a negative correlation coefficient around 10 o’clock, it was verified little or low correlationas the time progresses. ‘6701’ seed production has been analyzed in a difference humidity condition of the seed productionshowed high correlation around 14 o’clock. ‘6701’ and ‘6704’ seed production has been analyzed correlation with light intensity,seed production almost showed a negative correlation coefficient. Controlling relative humidity in the greenhouse are importantfactor to produce onion seed yielding under shading screen and ventilation condition.
