Genetic improvements in New Zealand forage cultivars

Abstract

Substantial genetic gains have been achieved across a range of temperate forage grass and legume species in New Zealand during the past 60 years. The genetic gains reported here compare favourably with those achieved in cereals and with those achieved for similar species internationally. Substantial improvements in grain yield of cereal crops have been achieved through changes in harvest index; however, increases in yield of forage grasses and legumes reflect increases in total above ground biomass. Rates of genetic gain have been lower in lucerne (Medicago sativa L.) than in red clover (Trifolium pratense L.) and white clover (Trifolium repens L.) and lower in perennial ryegrass (Lolium perenne L.) than in annual ryegrass (Lolium multiflorum Lam.) and tall fescue (Festuca arundinacea Schreb.). Gains in forage yield and quality have often exceeded 1% per year and have led to significant (0.3 to 1.3% per year) increases in animal performance. Keywords: animal performance, forages, genetic improvement, quality, symbiotic associations, yield