Agronomic value and morphophysiological diversity of non-Ladino Italian white clover wild populations compared with variety germplasm

Abstract

Non-Ladino Italian white clover wild populations are widespread in hill and mountain areas of the Alps and northern Apennines. The agronomic value of these populations is unknown. This study was based on results of four experiments and had the following objectives: (i) comparing 11 small-leaved or medium-leaved wild populations from these areas with eight medium-leaved or large-leaved varieties of different origin and one wild population from Sardinia, for forage yield in a mown association with cocksfoot, forage yield under sheep grazing, seed yield, forage quality, and 14 vegetative or reproductive traits; (ii) investigating the relationships among traits; (iii) assessing the association of individual trait expression with the environments of origin of the wild populations. Clover competitive ability was greater in large-leaved material, tended to imply higher total yield of the association, and was unrelated to clover yield under grazing. Most wild populations from northern Italy were acyanogenic, several exhibited high yield under grazing and high seed yield, and one medium-leaved wild population outperformed any medium-leaved variety for forage and seed yield traits. Higher altitude of collecting site of these populations was related to lower forage yield and smaller size of some traits. Pasture collecting habitat implied greater adaptation to grazing than woodland, greater competitive ability than wasteland, and several morphophysiological differences relative to populations collected from wasteland or meadow. The Sardinian wild population displayed low seed yield and high cyanogenic potential, whereas the Ladino variety Giga was top-performing for forage yield in association and seed yield. Several vegetative and reproductive traits showed covariation. The generated results can drive the exploitation of non-Ladino genetic resources from northern Italy.