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Water matricidal potential (kPa) of the substrate from August 18, 2016 to August 31, 2016. 

Water matricidal potential (kPa) of the substrate from August 18, 2016 to August 31, 2016. 

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Water stress can affect the yield in tomato crops and, despite this, there are few types of research aiming to select tomato genotypes resistant to the water stress using physiological parameters. This experiment aimed to study the variables that are related to the gas exchanges and the efficiency in water use, in the selection of tomato genotypes...

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... water availability of the substrate was not restrictive for the water demand of the plants (-10 kPa), until the deficit beginning. After 2 days of the water deficit imposition, during the physiologic evaluations, the substrate was submitted to a moderate matricidal potential (below -25 kPa) ( Figure 1). Guida et al. (2017), when submitting tomato plants to a water stress, observed that the soil matricidal potential below -28 kPa promotes a reduction in the stomatal conductance, affecting the crop yield. ...

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