Seed increase of tedera

Summary

Tedera (Bituminaria bituminosa var albomarginata and var. crassiuscula) originates from the Canary Islands, where it is a component of native pastures grazed by livestock or has been cut and carried as hay for dairy goats (Ventura et al. 2000). Tedera has potential as a new domesticated perennial legume due to its ability to produce edible dry matter all year round, retain green leaf over summer and autumn with minimal leaf shedding, tolerate extreme drought and is adapted to a range of soil and environmental conditions (Real et al. 2008; Real and Verbyla 2010). Over the period 2005 to 2009, tedera has been productive when established at five locations in south Western Australia with growing season rainfall varying from 330-600 mm, and a range of soil types (Real et al. 2008; Real and Verbyla 2010). In addition, tedera has demonstrated very good tolerance of, and recovery from, grazing and its nutritive value is comparable to that of lucerne (Ventura et al. 2000; Sternberg et al. 2006; Oldham et al. 2013a; Oldham et al. 2013b). Preliminary modelling results based on small scale trials reveal the potential of tedera to improve the profitability of permanent pastures and mixed cereal/livestock systems (Finlayson et al. 2012). The main contribution of tedera occurs during summer and autumn, replacing the need for supplementary feeding. However, benefits of tedera for animal production must be clearly demonstrated in grazing trials where animals are grazing tedera all year round. This project was established to multiply seed of tedera to enable grazing studies to be progressed.
Two sites located at J.A.V. Brown & Sons at Dandaragan and DAFWA’s intensive industries research station at Medina were established with 7 accessions of tedera (T4, T27, T31, T42, T43, T48 and T52). At Dandaragan, in September 2011, 1.4 ha was sown with seeds at a rate of 10 kg/ha using a cone-seeder at a sowing depth of 2.5 cm and a row spacing of 55cm. At Medina, in December 2011, 900 seedlings of each accession were transplanted at 30 cm spacing in 3 x 100 m rows per accession
At Dandaragan, two commercial scale harvesting options were tested; singleharvest with a conventional harvester on dry tedera,​multiple pass harvest on green tedera.

At Medina, two experimental harvesting techniques were used for small scale applications;hand-harvest from the plants and
collection of mature seeds dropped onto weed-stop matting that was laid on the ground for this purpose.