Common vetch (Vicia sativa L.) is a well-adapted winter legume in the Mediterranean area, used for both forage and grain production. Phosphorus (P) is a key nutrient influencing plant growth, development, yield, and nutritional quality. This study evaluated how phosphorus availability (0 vs. 60 kg ha−1 P2O5) affected the growth, physiological characteristics, yield and environmental resource-use efficiency of two common vetch cultivars, BK-45 and Evinos, over two growing seasons (2020–2021 and 2021–2022). Phosphorus fertilization significantly enhanced vegetative growth, increasing plant height (37.5%) and leaf area index (57%) compared with the control. Improved physiological performance was also observed, as P application increased the chlorophyll content (SPAD) and normalized difference vegetation index (NDVI), particularly during later growth stages. Evinos showed better growth and chlorophyll content around anthesis, whereas BK-45 retained more chlorophyll at maturity. These influences on canopy development and photosynthetic capacity translated into improved yield components, with increases in seeds per pod (40%) and pods per plant (33%), resulting in a higher seed yield (0.127 kg m−2 vs. 0.06 kg m−2 in the control). The dry biomass increased by 50%, with BK-45 showing the strongest response to P fertilization. P fertilization also improved water-use efficiency (WUE) and radiation-use efficiency (RUE), thereby promoting resource use and also the sustainability of the crop. These findings underscore that phosphorus fertilization plays a key role in improvement of common vetch seed yield, forage yield and the sustainability of the cultivars, with the interactions depending on the seasonal variation.
Papakaloudis et al. (Sat,) studied this question.