Cultivated lucerne is the most widely grown forage legume in pastoral agriculture. Persistence is critical for most pastoral production systems and its definition includes concepts of productivity, but maintenance of adequate plant numbers is essential. There were three important eras in lucerne persistence breeding: species introduction leading to local varieties and land races (adaptation), development of multiple pest-resistant, autumn dormancy-specific cultivars, and introducing complex traits and the use of biotechnologies. Today’s persistent cultivar needs, at a minimum, adaptation, proper autumn dormancy, and targeted pest resistances. Adding complex, ‘persistence-limiting’ traits to these minimum base traits, such as tolerance to grazing, acid, aluminum-toxic soils, and drought, is successfully being achieved via traditional selection, but biotechnologies and inter-specific hybridisations are also being employed in some cases. The main issues around biotechnologies are public perception and regulatory issues which continue to hamper transgene deployment while genetic marker programs need to lower costs and concentrate on successful application. There is not one persistent ‘ideotype’ that will fill all situations, but specific ones need to be developed and targeted for geographies such as the subtropics. Finally, breeders need to understand what persistence traits lucerne producers are willing to pay a premium to obtain.

Genetic improvement programs for livestock and pasture plants have been central to the development of the New Zealand (NZ) pastoral industry. Although genetic improvement of livestock is easily shown to improve animal production on-farm, the link between genetic improvement of pasture plants and animal production is less direct. For several reasons, gains in farm output arising from improved plant performance are more difficult to confirm than those arising from livestock improvement, which has led to some debate in the livestock industries about which plant traits to prioritise in future breeding programs to deliver the greatest benefit. This review investigates this situation, with the aim of understanding how genetic improvement of perennial ryegrass (Lolium perenne L.), the predominant pasture grass, may more directly contribute towards increased productivity in the NZ dairy industry. The review focuses on the dairy industry, since it is the largest contributor to the total value of NZ agricultural exports. Also, because rates of pasture renewal are greater in the dairy industry compared with the sheep and beef industries, genetic gain in pasture plants is likely to have the greatest impact if the correct plant traits are targeted. The review highlights that many aspects of ryegrass growth and ecology have been manipulated through breeding, with evidence to show that plant performance has been altered as a result. However, it is not clear to what extent these gains have contributed to the economic development of the NZ dairy industry. There are opportunities for breeders and scientists to work together more closely in defining economic traits that positively influence pasture performance and to translate this information to objectives for breeding programs, systematically linking information on the measured traits of ryegrass cultivars to economic values for those traits to assist farmer decision-making regarding the most appropriate cultivars to use in their farm system, and better defining genotype × environment interactions in key productivity traits of modern ryegrass cultivars. Changes in priorities for investment of public- and industry-good funds in forage improvement research and development will be needed if these opportunities are to be captured.

Post-anthesis water deficit and increasing vapour pressure deficit are common and can result in reduced grain yield and the development of small or shrivelled wheat kernels (screenings) that reduce grain value. Previous studies suggest incorporation of a tiller inhibition (tin) gene to restrict tiller number and thereby slow water use and promote the development of larger, fertile spikes to increase kernel weight. This paper reports on the influence of the tin gene on grain yield and screenings in multiple wheat genetic backgrounds assessed in field experiments in 2005 and 2006. Across environments, grain yield ranged from 0.90 to 5.50 t/ha and screenings from 4 to 20%. The effect of tin on grain yield and screenings varied with environment and genetic background. Grain yield was unchanged in tin lines derived from varieties Brookton, Chara, and Wyalkatchem assessed in southern Australian environments. However, there was a 31 and 10% advantage of free-tillering over tin-containing Silverstar lines for the 2005 western and 2006 northern experiments, respectively, resulting in an average 12% reduction in grain yield of Silverstar tin lines. In northern experiments, where screenings ranged from 4 to 12%, Silverstar-based tin lines produced significantly fewer screenings than free-tillering sister lines. Reduction in screenings was associated with a higher kernel weight ( 10%) and a tendency for lower grain yield, although individual Silverstar tin progeny with grain yield equivalent to the parent were readily identified. The incorporation of the tin gene has considerable potential to reduce the incidence of screenings in commercial wheat crops. Variation in grain yield associated with the tin gene was dependent on genetic background, with potential for selection of higher yielding tin progeny for commercial line development.

Adzuki bean germplasm was introduced to Australia from China as part of a program to develop better adapted varieties for the Australian sub-tropics than the current standard varieties derived from Japan, and to develop an export industry targeting Japan. Since adzuki was a new crop in Australia, the key questions were whether suitably adapted genotypes could be obtained from China, and whether these were higher yielding than the Japanese derived local standards and of acceptable seed quality.

A geographically stratified core collection of adzuki bean (Vigna angularis) landraces from China was field evaluated for agronomic and phenologic traits at sites in China in a related study, and also at Hermitage Research Station, Queensland, in the main target region for adzuki cultivation in Australia.

A relationship was found between the regional patterns of adaptation in the core collection grown in China and yield performance at Hermitage. In particular, the late maturing gene pool which originated from South China had the greatest yield at the lower latitude location in Australia, and a gene pool from central China combined both high yield and acceptable seed quality. These lines from China were superior in yield to the local standards, and many also had suitable seed quality for the Japanese market.

In further screening of these selections from Hermitage, they were also superior in yield to the local standards in central Queensland, but not in central New South Wales.

The breeding of higher yielding varieties for Queensland with suitable quality for the Japanese market is suggested, both by direct releases of identified Chinese accessions and by further crossing of the medium and late maturing superior selections from China with the local standard varieties Erimo and Bloodwood, which have the large red seed desired in Japan.

For New South Wales, one accession from China was comparable to the local checks and appears useful for gene pool diversification, however a separate introductory screening evaluation of Chinese germplasm in New South Wales is suggested to better identify promising accessions with phenology suited to the more temperate latitudes.

Thus characterisation of genetic diversity for adaptation can assist with the introduction of germplasm for a new crop. The diversity in the adzuki germplasm from China provided the needed phenologic flexibility for introduction of the crop to southern Queensland, with superior yield to the standard varieties from Japan and acceptable seed quality.

White clover is one of the most important pasture legumes in global temperate regions. It is an outcrossing, insect-pollinated species with gene flow occurring naturally between plants. A 2-year study was conducted to assess the relationship between gene flow and physical distance in white clover under field conditions in southern Australia. White clover plants exhibiting a red leaf mark phenotypic trait acted as pollen donors to recipient plants lacking leaf markings at distances up to 200 m distant from the donor plants. Progeny were scored for the dominant red-leafed phenotype and gene flow was modelled. Paternity was confirmed using simple sequence repeat markers. A leptokurtic pattern of gene flow was observed under conditions designed to measure maximised gene flow with the majority of pollination occurring in the first 50 m from the donor pollen source. The combined use of simple sequence repeat and visual markers confirmed that there was also a white clover pollen source in addition to the donor plants. This research confirms the difficulty in ensuring absolute containment of gene flow in an outcrossing species grown in an environment when endemic populations are known to exist.

Messina [Melilotus siculus (Turra) Vitman ex. B. D Jacks] is a salt- and waterlogging-tolerant annual legume that could be highly productive on saline land. Arbuscular mycorrhizal (AM) fungi form a symbiotic relationship with the majority of terrestrial plant species, and improved productivity of plants inoculated with AM fungi under saline conditions has been attributed to the increased uptake of nutrients such as phosphorus (P). However, the mycorrhizal status of M. siculus under saline or non-saline conditions is unknown, as is the role of AM in improved nutrition and nodulation. In this study, the role of AM fungi in growth improvement and nodulation of M. siculus was examined in saline and non-saline soil. The M. siculus plants were inoculated with either a single AM species or mixed AM species, or remained uninoculated, and were grown at three levels of sodium chloride (NaCl) (0, 80, and 250 mm NaCl). AM-inoculated plants had significantly greater nodulation than plants that did not receive AM inoculum, regardless of salinity level. Plants inoculated with mixed AM species at 250 mm NaCl showed improved survival (90%) compared with the plants inoculated with single AM species or uninoculated control plants (30%). Within each salinity level, plants inoculated with mixed AM species had significantly greater dry weight than all other treatments. In addition, plants inoculated with mixed AM species had increased total uptake of P. It is likely that the increased growth observed in AM-inoculated M. siculus plants is due to improved P nutrition, showing the potential of AM fungi to enhance the growth of M. siculus on saline land.

Soil water availability is one of the main factors determining plant growth and forage production. The effects of soil water deficit on the development of two woody Mediterranean Medicago species, M. arborea and M. citrina were studied. A field experiment was carried out in the University of the Balearic Islands (Spain), under irrigated and drought conditions on both non-defoliated plants (NDP) and defoliated plants (DP).

Under drought, all studied parameters for NDP were affected by water stress in summer, though there were no significant differences between species for shoot biomass (B). However, M. citrina maintained significantly higher leaf biomass than M. arborea, which represents a great part of B. On the contrary, M. arborea plants suffered total leaf senescence in summer, and B was totally composed of woody parts.

For DP, spring–autumn was a favourable period for plant growth and development, under both water regimes. In well irrigated M. citrina plants, and compared with M. arborea, the capacity of regrowth was higher, and leaf area was similar for NDP and for DP. During summer, the regrowth was sensitive to the extreme temperatures. In drought conditions, the capacity of regrowth was relatively favoured in spring but completely inhibited in summer for both species.