In this section:
SARDI Five Description
Description of “SARDI Five” Lucerne (Medicago sativa)
Alan Humphries, Eric Kobelt and Geoff Auricht
A fact sheet of this variety is also available
GENERAL DESCRIPTION:
SARDI Five is a semi winter dormant variety (class 5), with a bushy appearance, fine stems and dark green leaves. SARDI Five has a low, broad crown, which makes the plant very persistent under grazing.
SARDI Five performs well in both irrigated and dryland environments, and is well suited to permanent stands of lucerne, where persistence, summer production and herbage quality are the most important attributes. SARDI Five is more persistent than other lucerne varieties in Australia. SARDI Five also has a very high level of resistance to each of the 4 major lucerne diseases and pests (Phytophthora, anthracnose, and spotted alfalfa and blue green aphids). This results in a cultivar that is well suited to challenging, wet, cold environments, or sites with a known high disease pressure.
SARDI Five should be the first choice for permanent lucerne stands under sheep or cattle grazing in high rainfall environments, and also in specialised hay production ventures where prime quality hay is required.
BACKGROUND/BREEDING:
The breeding line L1000 was intentionally developed from six winter dormant experimental breeding lines (L717, L720, L721, L756, L791, and C48). They were first trialed in 1997 with many of these field trials still extant in 2006. These advanced breeding lines as well as their former generations, had been field and glasshouse selected for 1) good field persistence and production, 2) good resistance to aphid, disease and nematode pests, 3) leafy and bushy growth habit, and 4) moderate to low winter growth (rating 5-6). Through parent plant selection from these lines the aim was to improve the uniformity, appearance, pest resistance, and quality characteristics, while at least maintaining all the other characteristics listed above. This aim was achieved in 2003 with L1000 as described below.
Initial selection of 25 plants from each of the six breeding lines was for dormancy, uniformity and quality characteristics in late August 2001. Plants were dug from plots in ‘old’ field trial sites sown 1998 in farmer’s paddocks. One hundred and twenty healthy disease-free plants with large leafy crowns, fine stems, and dark green foliage colour were selected from this group.
Twelve of the 120 plants, two from each of the six parent lines, were chosen as pollen parents for test crossing with the remaining 104 plants as maternal parents. Extra clones were struck of the pollen parents to provide sufficient pollen for the test crosses. Progeny from each cross was tested for resistance to 1) spotted alfalfa aphid, 2) blue green aphid, 3) anthracnose, and 4) Phytophthora root rot. High levels of resistance, to all four pests collectively, were used to select the 30 best parent clones having high specific and general combing abilities for overall pest resistance. Three of the six lines had 6 plants chosen and the three others had 4 each chosen for the final 30.
In the summer of 2002/03 the 30 selected parent plants (together with their clones totalling over 180 surviving plants) were randomly inter-crossed in cages by honeybees. Breeder’s seed, coded “L1000”, was harvested first in late autumn of 2003.
PRODUCT FIT/END USE:
A semi-winter dormant variety of dormancy 5 is best suited to farming systems where long-term persistence, summer production and herbage quality are the most desired traits, and winter production is either not wanted, or is obtained by growing SARDI Five in a mixed pasture with annual or perennial grasses (ryegrass, fescue, etc)
SARDI Five is also an excellent choice for specialised hay producers, because of its fine, leafy stems.
DISEASE/PEST RESISTANCE:
SARDI Five has the highest disease/insect resistance profile of any lucerne tested at SARDI. This variety is now used as our highly resistant control (>50% resistance) to Anthracnose, Phytophthora, Spotted, and Blue Green Aphids.
The high level of disease resistance provides a level of insurance that the variety will perform in a wide range of environments that may include a number of diseases in combination. This is often the case where there is a long history of lucerne production, with irrigation generally multiplying the effect. SARDI Five performs exceptionally well under these conditions.
SARDI Five is also resistant to the newly discovered race of Anthracnose (Race 2), discovered in Queensland Australia in 2004/5.
Table 1. shows SARDI Five’s broad pathogen resistance profile.
Table 1. Disease and insect resistance of ‘SARDI Five’ lucerne cultivar
|
Spotted Alfalfa Aphid |
Blue Green Aphid | Phytophthora Root Rot | |
|---|---|---|---|
| HR (53%) | HR (51%) | HR (56%) | HR (52%) |
*Colletotrichum trifolii races 1and 4. SARDI Five is Resistant (R 33%) to Race 2.
TRIAL RESULTS:
SARDI Five was developed using our extensive network of field trials. In 2005, SARDI Five parent lines had been evaluated in 43 trails across all states of Australia (table 1). The sites are used to evaluate elite breeding material and to select (by digging up and planting in our nursery) the best plants from different environments around Australia.
The parent lines of SARDI Five have shown excellent long-term persistence across a broad range of environments (figures 1-5). The breeders’ seed of SARDI Five was harvested in 2003, so it is too early to show long-term persistence for the final synthetic, but early results are very encouraging (refer to Appendix for early results).
SARDI Five excels in mixtures with other pasture species, which is often challenging for lucerne. The cultivar is also very grazing tolerant, as identified in our continuous grazing trials at Turretfield, South Australia.
Table 2. List of 43 trial sites where SARDI Five parent lines were evaluated
| Flaxley 1997 | Lake Bolac 2002 | Howlong 1998 |
| Balmoral 1997 | Langhorne Creek 1997 | Petersville 1999 |
| Berrigan 2002 | Maroona 2005 | Petersville 2004 |
| Boort 2001 | Meningie2005 | Ponde 1999 |
| Canownindra 1999 | Mid North 2003 | Gatton 1998 |
| Coolah 2003 | Mid North 1997 | Roseworthy 1997 |
| Cootamundra 2002 | Mount Gambier 1998 | Roseworthy 1998 |
| Cowra 2003 | Mount Gambier 2003 | Keith 1998 |
| Flaxley 1998 | Mullaley 2003 | SE SA 1999 |
| Forbes 2002 | Aberdeen 2000 | Toogoolawah 2004 |
| Gidginbung 2004 | Aberdeen 1998 | Katanning 1999 |
| Howlong 2003 | Boort 1998 | Wagga East 1999 |
| Inglewood 2002 | Canowindra 1997 | Wall Flat 1997 |
| Kapunda 2003 | Howlong 1997 | Wall Flat 1998 |
| KiKi 1997 |
Figure (1). Average Persistence of semi-winter dormant lucerne cultivars in Australia, after 4 years. These results represent the results from up to 22 trials sown between 1999 and 2002 (number of trials for each variety shown in brackets). The results show, with the exception of SARDI Five, a decline in persistence after 4 years.
Figure 2. Plant frequency of dormancy class 5-7 varieties at Flaxley, in the Adelaide Hills in SA after 6 years. This site was sown in 1998 in a cold, high rainfall environment with heavy soils and temporary waterlogging. The SARDI Five parent lines in this trial, L717, L720, L721 and L719 have far greater persistence (measure using plant frequency, the % crowns present / m2) than existing cultivars.
Figure 3. Plant frequency of SARDI Five parent lines and cultivars at Mount Gambier, SA after 6 years. The Mount Gambier site (sown in 1998) is a high rainfall, cool climate irrigated dairy farm. The site is under intensive management, strict rotational grazing, and a high presence of volunteer grasses that dominate winter production and compete with the lucerne.
Figure 4. Plant frequency of SARDI Five parent lines and cultivars at Canowindra, NSW after 4 years. The Canowindra site was (sown in 1997) located in flood irrigation bays on the edge of the Lachlan River. The site has heavy soil, high disease pressure and suffers from salinity.
Figure 5. Plant frequency of SARDI Five parent lines and cultivars at Ponde, SA after 3.5 years. The site was sown in 1999 on the flood irrigation bays on the Murray River. The site has a long history of lucerne, and consequently has high disease pressure. The bays receive flooding during summer thunderstorms, and may be submerged for 6-10 days.
APPENDIX: Preliminary results for SARDI Five after 3 years
Figure 6. Persistence of SARDI Five and other cultivars at Wall Flat, after 3 years. The Wall flat site (sown in January 2004) is located on an irrigated dairy farm on the Murray River. The site has intensive grazing management, high disease pressure, and strong competition from volunteer grasses.
