A Stability Analysis Using AΜΜΙ and GGE Biplot Approach on Forage Yield Assessment of Common Vetch in Both Conventional and Low-Input Cultivation Systems

Abstract
Common vetch (Vicia sativa L.) is a widespread legume crop in the Mediterranean mega-environment, due to its versatile uses and its compatibility with organic and low-input farming systems. However, its adaptation to various such environments should be studied and varieties suitable for forage yield must be selected. This study aimed to explore forage yield stability of common vetch varieties based on the stability index, with a specific target to explore common vetch variety behavior in various environments. Six Greek varieties of common vetch were used over four environments for two years. The cultivation was conducted using a strip plot with the varieties randomized within each plot in both conventional and low-input cultivation systems. (Alexandros) and (Tempi) varieties showed stability for days to 50% of flowering (index >4000), while (Pigasos) and (Zefyros) for fresh forage yield (>200) across environments. Combined estimations, also showed stability of (Pigasos) and (Zefyros) for fresh forage yield. Comparisons between the conventional and low-input farming systems generally showed minor differences but revealed varieties that exhibit stable performance even in the low-input farming systems, where stability is generally a little higher. The AMMI and GGE biplot analysis depicted the stability performance of the varieties regarding the traits under experimentation. As far as the fresh forage and dry matter yield, (Zefyros) was the most stable and productive variety over all others. Correlations between traits displayed the positive relation of fresh forage yield with days for 50% flowering and dry forage yield. Positive correlations may be proved useful for indirect breeding through traits with high stability leading to the selection of traits that show low stability.