Abstract: The study on the effects of daytime sub?high temperature (30 and 35 ℃) in spring and autumn on the growth,development,yield and quality of greenhouse tomato in northeast China showed that compared with the plant growing under feasible temperature 25 ℃,three days' daytime sub-high temperature increased the relative growth significantly,and made the plant spindling.Seven days or more sub-high temperature made the plant grow fast,with thinner leaves and presenility.Under sub-high temperature,the harvest time was earlier,the fruit weight and the 2nd and 3rd inflorescence lessened,the quality of fruit decreased,and the yield decreased significantly. Sub-high temperature had a strong influence on the normal growth and development of greenhouse tomato.The longer the plant suffered sub-high temperature from flower bud differentiation to fruit maturing,the worse the fruit quality,and the lower the yield would be.

Key words: Grassland, Free grazing, Uptake and emission