Growth and Maintenance Respiration in Whole Plants, Tops, and Roots of Lolium multiflorum

摘要: Continuous measurements of CO2-exchange were separately carried out on tops and roots small swards Lolium multiflorum grown in nutrient solution growth chamber during 3–4 weeks. From these measurements, a daily carbon balance accumulated dry matter could be established. The data used to distinguish between two components respiration, one proportional or photosynthesis (growth respiration), the other plant weight (maintenance respiration). The separation respiration was made by multiple regression analyses with rate as independent variables. To ensure independency variables period, varied application alternate three-day periods high low irradiance. coefficients, efficiency converting assimilates into constructive (YG) maintenance coefficient (M) derived. Three experiments varying length photoperiod dark period out. for whole-plant separately. Growth whole plants well lower — hence efficiencies higher longer photoperiods were. than tops. root may originate from release HCO3− exchange NO3−. parameters found can utilized quantitatively computer models crop respiration.