Fluctuations in Radiation Use Efficiency Throughout the Growth Cycle in Diploid Potato Crop

Abstract

The capture of incoming solar radiation under unlimited light, water, and nutrient conditions by plant canopies and converting it into biomass has been described as radiation use efficiency (RUE). RUE has been computed as a function of biomass accumulation and intercepted photosynthetically active radiation without considering the loss of photoassimilates due to respiratory processes. This study evaluated the RUE in diploid potato crop (Solanum phureja Juz. et Buk.) across six experiments in Colombia. Total biomass was measured during the crop season from the early vegetative stage through maturity. However, this proposal involves not only the total biomass accumulated concerning the amount of photosynthetically active radiation intercepted but also took into account the losses by respiration, following Thornley respiration approach. This research demonstrates that the RUE is not a constant value as the respiration process leads to RUE values being variable in a non-linear way over time. The daily RUE simulation, conducted through an interpolation process, revealed significant variation from emergence to the end of the cycle. This indicates an error in assuming a constant RUE throughout the entire growth period, particularly in assessing its physiological impact across the entire growth and development crop cycle.