Persistence and productivity of Medicago sativa subspecies sativa, caerulea, falcata and varia accessions at three intermittently dry sites in south-eastern Australia

2010 ◽  
Vol 61 (8) ◽  
pp. 645 ◽  
Author(s):  
G. D. Li ◽  
Z. N. Nie ◽  
S. P. Boschma ◽  
B. S. Dear ◽  
G. M. Lodge ◽  
...  

The persistence and productivity of a diverse range of Medicago sativa germplasm including representatives of subspecies sativa, caerulea, falcata and varia were examined at 3 field sites in south-eastern Australia over 4 years. Sites were located at Tamworth, Barmedman and Hamilton, forming a 1200 km north–south transect with rainfall distribution varying from predominantly summer dominant in the north to winter dominant at the most southerly site. Several entries of subspecies varia and caerulea had herbage yields and persistence equivalent to that of M. sativa subspecies sativa cultivar Sceptre, a highly winter-active type that was used as a standard. The cultivar Cancreep, a cross of M. falcata and M. sativa, had a total yield over 3 years equivalent to 84–91% of Sceptre at the 2 sites where it was sown. Individual lines of subspecies varia demonstrated good persistence under grazing and were ranked 2nd and 6th out of 35 accessions for frequency in year 4 at Barmedman, the driest site, and 5th, 7th and 9th out of 33 accessions at Tamworth, the more summer-dominant rainfall site. Entries of subspecies falcata were among the least productive and persistent. The study indicated that germplasm from subspecies caerulea and varia offered hitherto unexploited potential for selection as persistent and drought-tolerant perennial legume alternatives to M. sativa for extensive low management grazing systems of south-eastern Australia.

Zootaxa ◽  
2009 ◽  
Vol 1980 (1) ◽  
pp. 1-15 ◽  
Author(s):  
JEAN JUST

The varying concepts of Janirellidae Menzies, 1956 are outlined, including its rejection by several authors. The view of Wilson and Wägele of Janirellidae being a valid family comprising Janirella Bonnier, 1896 and presumably Dactylostylis Richardson, 1911 (= Spinianirella Menzies, 1962) is accepted. Diagnoses of the Janirellidae subsequent to Menzies’ original one were based on the inclusion of a diverse range of genera now recognised as not belonging in that family. A new diagnosis of Janirellidae is presented based on the inclusion of Janirella, Dactylostylis, and a new genus Triaina with two new species, T. isodonte and T. makridonte, from south-eastern Australia. The latter species represents the shallowest record (80 m) of the otherwise predominantly deep-water family. All species in the family are listed in an appendix, with area of type locality and depth range.


2007 ◽  
Vol 55 (3) ◽  
pp. 177 ◽  
Author(s):  
Vicki L. Stokes ◽  
David M. Spratt ◽  
Peter B. Banks ◽  
Roger P. Pech ◽  
Richard L. Williams

The distributions of the introduced nematode parasite, Angiostrongylus cantonensis, and the native Angiostrongylus mackerrasae in Australia are poorly understood. We sampled rodents and/or their faeces, and intermediate gastropod hosts for the presence of Angiostrongylus species in coastal forests surrounding Jervis Bay in south-eastern Australia. We found A. cantonensis in populations of introduced Rattus rattus in forests to the north of Jervis Bay, and A. mackerrasae in native Rattus fuscipes in forests to the south of Jervis Bay. The apparent geographical separation of these lungworm species may be a consequence of host specificity and negative associations between R. rattus and R. fuscipes that results from interspecific competition. A. cantonensis was regularly found in R. rattus or their faeces across 9 of 12 study sites north of Jervis Bay, and three species of snail common to the area were suitable intermediate hosts. This has potential negative implications for native wildlife and human visitors to these forests, because A. cantonensis infection causes zoonotic disease (neuro-angiostrongyliasis) in humans and a wide range of bird and mammal hosts. Management of pest rodents in the study area is warranted.


2015 ◽  
Vol 66 (4) ◽  
pp. 377 ◽  
Author(s):  
H. Dove ◽  
J. A. Kirkegaard ◽  
W. M. Kelman ◽  
S. J. Sprague ◽  
S. E. McDonald ◽  
...  

In south-eastern Australia, low winter temperatures often reduce pasture growth and thus winter herbage supply relative to livestock requirements. Grazing of vegetative grain crops in winter is one strategy that might overcome this feed gap. In a study with young sheep over two seasons near Canberra, ACT, we compared pasture-only grazing with three separate crop–livestock systems in which the sheep grazed long-season wheat, winter canola or a combination of these, for intervals over the period May–August. We measured forage biomass, sheep grazing days (SGD) and liveweight accumulated per ha. Crop-grazing treatments resulted in much more winter forage for grazing sheep (t DM ha–1): in 2010, one crop 2.5–3.0, two crops 3.5 v. pasture only 1; in 2011, one crop 2, two crops 3 v. pasture only 1.4. In the first season, grazing one crop resulted in ~2000 extra SGD ha–1 and the accumulation of more liveweight per ha than in the pasture-only treatment; grazing of two crops resulted in >3500 extra SGD ha–1. Equivalent values in the second, drier season were: one crop, ~1000 extra SGD ha–1; two crops, 2600 extra SGD ha–1. Spelling of pastures during crop grazing led to extra pasture growth, such that in each of the two seasons, 40% of the total benefit in extra SGD per ha came from the extra pasture. The results indicate that, like grazed wheat, grazed canola can provide valuable winter forage, especially when used together with wheat. The data also provide the first quantification of the effect of crop grazing on pasture spelling and subsequent pasture supply, and suggest value in the incorporation of grazing wheat and canola into grazing systems in the high-rainfall zone.


2019 ◽  
Vol 70 (12) ◽  
pp. 1141 ◽  
Author(s):  
R. C. Hayes ◽  
I. Ara ◽  
W. B. Badgery ◽  
R. A. Culvenor ◽  
R. E. Haling ◽  
...  

This review examines the prospect of improving perennial legume adaptation to grazed mixed pasture swards across the higher-altitude regions of south-eastern Australia through improved management, particularly as it relates to soil fertility. The range of adapted perennial species available to farmers often remains limited to only one perennial forage legume species, white clover (Trifolium repens L.). Despite recent advances in cultivars for increased persistence in dryland environments, white clover remains sensitive to drought with its inherently shallow root system and limited capacity to restrict water loss from herbage. With few alternative species likely to become widely available in the foreseeable future, prospects for extending the boundaries of perennial legume adaptation likely rely on a dual approach of improving soil fertility and further genetic improvement in white clover. Improved soil fertility would focus on overcoming soil acidity and addressing nutrient deficiencies, particularly of phosphorus, potassium, boron and molybdenum, which tend to be more widespread in the target region. Addressing these soil constraints would alleviate periodic moisture stress by: (1) increased water availability through improved infiltration and soil hydraulic properties; (2) increased root growth to maximise exploration of the soil volume; and (3) better maintenance of plant cell structures to foster improved osmotic regulation. However, the extent to which white clover adaption may be extended remains an issue of further research. This review highlights an opportunity for further genetic improvement of white clover by focusing on improving the capacity to recover from periodic droughts through seedling regeneration. Further breeding efforts in white clover should examine the feasibility of selecting for hard seed characteristics more similar to the best-adapted subterranean clover (Trifolium subterraneum L.) cultivars across this region to promote ongoing seedling regeneration.


Phytotaxa ◽  
2020 ◽  
Vol 437 (2) ◽  
pp. 66-72
Author(s):  
ANDREW J. PERKINS

Hydrocotyle simulans, a new perennial species from south-eastern Australia, is here described with associated illustration, photographic images and distribution map. The new species is restricted mostly to freshwater swamps in coastal areas of south-eastern South Australia, southern Victoria and to the Furneaux Group of islands, off the north-eastern coast of Tasmania. Hydrocotyle simulans resembles both H. plebeya and H. pterocarpa, in having orbicular-cordate to reniform leaves, hydathodes along leaf lamina margins and broadly ovate to orbicular stipules with entire margins. It differs from these taxa by a combination of characters, such as reflexed white trichomes congregated at the petiole apices, ovate floral bracts with basal lobes, subsessile flowers with pale to dark crimson petals and lenticular mericarps with minutely rugulose surfaces when mature.


1995 ◽  
Vol 43 (1) ◽  
pp. 31 ◽  
Author(s):  
K Breuer ◽  
A Lill ◽  
J Baldwin

Haematological parameters and body mass of four passerine bird species resident in south-eastern Australia were compared in winter and summer to determine whether there were changes indicative of metabolic adjustments associated with seasonal acclimatisation. Haematocrit and whole-blood haemoglobin content did not change seasonally, but erythrocyte numbers increased (by 45-72%) and erythrocyte volume decreased (by 40-73%) significantly in winter in all species. The greater surface area to volume ratio and shorter diffusion pathway of smaller erythrocytes in winter should enhance blood oxygen transport efficiency and thus potentially facilitate metabolic acclimatisation to cold stress. Only one species showed a significant, but small (3%), increase in body mass in winter, suggesting only a minor role for winter fattening in any such seasonal metabolic adjustments in the species studied. The findings contrast with those for some passerines overwintering in the north temperate zone, but the generality of these possible north-south differences needs further investigation.


2007 ◽  
Vol 47 (2) ◽  
pp. 136 ◽  
Author(s):  
R. A. Culvenor ◽  
S. P. Boschma ◽  
K. F. M. Reed

Three winter-active populations of phalaris (Phalaris aquatica L.), selected over two generations for improved persistence under grazing, were evaluated with commercial cultivars of phalaris and other temperate perennial grasses from 1999–2003 in three environments of south-eastern Australia as part of a program to develop a cultivar for more sustainable pastures and to assess genotype × environment interaction. Grazed sites were located at Bulart in western Victoria, and Rye Park on the Southern Tablelands and Tamworth on the North West Slopes of New South Wales. At the conclusion of the experiment, the frequency of live plant base was highest at Rye Park despite soil acidity and drought. Significant variance among half-sib families in each population was also observed most frequently at this site. Frequency was intermediate at Bulart but lower than expected considering high soil fertility, probably because of high grazing pressure. Frequency was lowest at Tamworth where severe drought occurred from 2001 onwards. There was significant genotype × environment interaction for frequency among half-sib families. Significant common family variance for frequency across the Bulart and Rye Park sites was demonstrated, but not between Tamworth and either of the other sites in later years. The relationship between winter herbage mass potential and persistence differed with population and site, and was negative for one population at Bulart but positive for another population at Tamworth. Mean persistence of all families was 30% higher than winter-active controls at Rye Park and at least 40% higher at Bulart. Phalaris generally persisted better than cultivars of tall fescue (Festuca arundinacea Schreb.), cocksfoot (Dactylis glomerata L.) and perennial ryegrass (Lolium perenne L.) with some exceptions, particularly at Bulart. Development of a winter-active phalaris cultivar with improved persistence under grazing was considered possible for the Southern Tablelands and western Victorian environments with these populations but a separate program using additional germplasm will be needed for the North West Slopes environment.


Sign in / Sign up

Export Citation Format

Share Document