Festuca apennina – a Future for the ‘Ryegrass of Alpine Pastures’?

Widespread in the Swiss alpine region, Festuca apennina could serve as a fodder plant for higher elevations. It also forms vigorous hybrids with meadow fescue and ryegrass. Does this make it suitable for improvement by breeding?

Which fodder plants are suitable for higher elevations where extreme weather conditions and short growing seasons prevail? Back at the beginning of the 20^th century, Friedrich Stebler, the first director of the subsequently founded Swiss agricultural research stations, described Festuca apennina (see box) as a potentially valuable fodder plant for the alpine region. Until now, however, its agronomic potential was largely unknown.

We investigated the occurrence of Festuca apennina and its preferences in terms of elevation as well as nutrient and water balance, focusing in particular on the naturally occurring hybrids that it forms with meadow fescue and ryegrass. Comparative field trials at different elevations were carried out to assess the potential of possible breeding activities.

Elevation is key for prevalence

Festuca apennina was found to be widespread in alpine meadows above 1500m.a.s.l., preferring nutrient-rich sites with ample water supply. At intermediate elevations, particularly between 1350 and 1450m, it faces strong competition from naturally occurring hybrids (the products of crossings) of Festuca apennina and meadow fescue (see graph).

Such crossings were also easily created by controlled mutual pollination. In growing trials, the hybrids often grew several times more abundantly than both parent species (heterosis or hybrid-vigour effect). At certain alpine locations, the hybrids were present in downright invasive numbers, due inter alia to a massive clonal spread caused by long rhizomes. Such swards are reminiscent of Italian ryegrass meadows on the Swiss Central Plateau.

Natural crossing with ryegrass

Hybrids of Festuca apennina and ryegrass were also discovered and investigated for the first time. Intergeneric hybrids of this type are termed Festulolium and in breeding terms are deemed to be promising for combining benefits of both genera.  The discovered Festulolium hybrids are relatively rare, but they too can spread over more than 100 metres via rhizomes. They are one of the few known examples where Festulolium hybrids occurring without human intervention can establish and thrive in nature.

Sterility as an impediment to propagation

Both hybrid forms are almost completely sterile, i.e. they are non-seed-forming (see box). The indehiscent anthers are the feature by which they are most readily recognisable. To exploit the agronomic potential of these hybrids, ways would have to be found to propagate them. Doubling the number of sets of chromosomes could restore their fertility. Vegetative propagation would also be a promising solution for use in small-scale cultivation niches, e.g. for the remediation of weed-infested animal resting-place patches.

Festuca apennina is on a par with meadow fescue

Twenty accessions of Festuca apennina from nine different mountain cantons were collected, propagated in isolation and their seed stored in the gene bank. Although the plants were inferior to meadow fescue when grown on the Swiss Central Plateau, the best accessions in the growing trial at 1000m.a.s.l. were on a par with recommended varieties of meadow fescue as the trial progressed. Strong dormancy and high seed shedding are traits that would have to be improved in a possible breeding programme. The results of our trials allow the selection of suitable germplasm for this.