Question

what will be the transpiration rate during day or night?

Answer 1

Day- and night-time transpiration, and leaf growth in hydroponically grown barley plants with (partially) excised root system. Barley plants had an intact seminal root system (control); or had three or five of six seminal roots removed close to the root base, just above the nutrient solution (the cut was sealed with Vaseline); or all six roots removed close to the base, with the cut end extending ∼2 cm into the nutrient solution; or had the tip 2 cm of all six seminal roots removed, with the cut end extending into the nutrient solution. Only seminal roots were manipulated, since adventitious roots were developed little and contributed little to water uptake in control plants (compare with Fig. 4). (A) Continuous recordings of transpiration. Transpirational water loss was related to total leaf area as determined at the end of experiments. The part of traces that is boxed in was used to calculate average transpiration rates during the day and night shown in (B) [means±SD of five (control) and three (treatments) plant analyses]. (C) Growth of leaf 3 in plants with an intact root system (control) and in plants that had three or five of six seminal roots excised; means±SD of 12 plant analyses from three batches of plants. In (B) statistically significant differences between transpiration rates are indicated by different letters (P<0.05, Student's t-test).