Photosynthetic activity and OJIP fluorescence with the application of a nutritional solution

The effects of macronutrients (Mg and P), and micronutrients (Mn, Cu, and Fe) application on the physiological performance of the photosynthetic apparatus were examined using the A/Ci curve and transient OJIP fluorescence methods. It was also evaluated the impact on the production, and dry matter of roots. The nutrients studied are responsible for several physiological mechanisms, such as the activation of enzymes, the constitution of chlorophyll, formation of ATP, DNA, and RNA, among others. Transient fluorescence parameters provide quick information on a wide range of photosynthetic component processes and can assist in understanding photosynthetic performance. For this purpose, a study was carried out with four concentrations of a nutrient solution (Mg, P, Mn, Cu, and Fe), and two application times, vegetation/reproduction and only reproduction stage. The nutrient solution application influenced positively the photosynthetic performance indexes, production, and root biomass. The increase in most photosynthetic indicators or reaction centers of different fluxes was positively impacted by different concentrations and at different times of application. The performance index on an absorption basis, PIABS, and quantum efficiency (phi Eo) were the most sensitive parameters to applications. Thus, the OJIP methods parameters that incorporate electron transport in addition to the PSII, can indicate useful parameters for determining the physiological performance of a nutritional solution.

Automated summary

The application of various nutrients positively impacts the photosynthetic performance and growth of plants, especially at different concentrations and stages of application, leading to significant increases in photosynthetic efficiency and yield.