Persistence and productivity of phalaris (Phalaris aquatica) germplasm in dry marginal rainfall environments of south-eastern Australia

2017 ◽  
Vol 68 (8) ◽  
pp. 781
Author(s):  
R. A. Culvenor ◽  
M. R. Norton ◽  
J. De Faveri
Keyword(s):  
Environmental Benefits ◽  
Annual Rainfall ◽  
Summer Drought ◽  
Environment Interaction ◽  
Phalaris Aquatica ◽  
Mixed Farming ◽  
Eastern Australia ◽  
Summer Dormancy ◽  
Average Annual Rainfall ◽  
Establishment Phase

Perennial grasses have production and environmental benefits in areas of southern Australia typified by the mixed farming zone of southern New South Wales (NSW). The perennial grass phalaris (Phalaris aquatica L.) is widely used in southern Australia; however, it would find more use in the mixed farming zone if its persistence in marginal rainfall areas (450–500 mm average annual rainfall) were improved. We evaluated a range of germplasm (n = 29) including wild accessions, lines bred from these, and existing cultivars for persistence and production at three sites in a summer-dry area of southern NSW with 430–460-mm average annual rainfall. Two sites were used over 4 years and the third site over 5 years. Summer dormancy, maturity time and seedling growth were also assessed. Analysis of genotype × environment interaction employing factor analytic models and accounting for spatial and temporal correlations indicated that changes in persistence occurred mainly over time rather than between sites. Ranking changes occurred in the dry establishment phase of the experiment and during a severe final summer drought, with few changes occurring in the intervening high-rainfall years. Lines that survived the establishment phase best had vigorous seedlings and earlier maturity, whereas those surviving the final summer best were earlier maturing and higher in summer dormancy with high winter-growth activity. Some later maturing lines within the higher summer dormancy group were less persistent. Some accessions from North Africa were the most persistent; also, populations bred from these and other more persistent accessions generally persisted and produced better than cultivars used presently. However, present cultivars were capable of high yield in the higher rainfall years. We suggest that persistence of higher summer dormancy cultivars over very dry years could be improved by selecting for earlier maturity time.

Cyclic salt as a dominant factor in the genesis of soils in South-Eastern Australia.

1954 ◽  
Vol 5 (3) ◽  
pp. 448 ◽  
Author(s):  
RG Downes
Keyword(s):  
Physical Properties ◽  
Dominant Factor ◽  
Annual Rainfall ◽  
Arid Soils ◽  
South Eastern ◽  
Eastern Australia ◽  
Average Annual Rainfall ◽  
Soil Distribution ◽  
Genesis Of Soils ◽  
South Eastern Australia

A theory is presented suggesting that during the Recent Arid Period the rainfall was approximately half that of the present day and enabled cyclic salt to be accumulated in areas in south-eastern Australia, where it does not 'accumulate at present. The salinization and subsequent desalinization during the wetter conditions since the Arid Period have operated with varying degrees of intensity to produce solods, solodic and solonized soils over large areas. However, irrespective of the degree of intensity, some of the pre-Arid soils because of their chemical or physical properties have been able to resist these processes and remain unaffected. Five "pedogenetic zones" have been defined according to the degrees of intensity with which the salinization and desalinization processes are thought to have operated, and it is found that soil distribution and morphology is correlated with these defined zones. The zone in which the effect has been most intense has an average annual rainfall at present of between 20 and 30 in., and the most widespread soils, those formerly called red and yellow podzolics, are solodic soils and solods. The theory provides a reasonable explanation for the anoxalous distribution of soils within the "podzol" zone where those showing the greatest degree of horizon differentiation (solods and solodic soils) occur in the driest parts. In addition, the postulated processes for the formation of the soils provide a reason why molybdenum deficiency is so common on these soils in zone 3.

Recurrent selection for grazing tolerance in winter-active populations of the perennial grass, Phalaris aquatica L.

2006 ◽  
Vol 12 ◽  
pp. 89-92
Author(s):  
Richard Culvenor ◽  
Suzanne Boschma ◽  
Kevin Reed
Keyword(s):  
Recurrent Selection ◽  
Perennial Grass ◽  
Grazing Pressure ◽  
Soil Conditions ◽  
Environment Interaction ◽  
Response To Selection ◽  
North West ◽  
Phalaris Aquatica ◽  
Eastern Australia ◽  
Selection For

Phalaris (Phalaris aquatica L.) is a perennial grass of Mediterranean origin used widely by the sheep and cattle industries of south-eastern Australia. Winter-active cultivars released since the 1970's have the potential for higher herbage productivity than the earlier, semi-winter dormant cultivars but have been reported to be less persistent under sub-optimal grazing management and soil conditions. To improve genetic potential for persistence in winter-active phalaris, a program of recurrent selection was conducted by subjecting three populations of half-sib families to two cycles of selection for persistence under heavy, largely continuous grazing pressure. Cycle 2 progeny families and bulked seedlots of each generation were grown in separate grazed plot trials in Western Victoria and the Southern Tablelands and North-West Slopes of New South Wales from 1999-2003 to assess response to selection. Positive linear response to selection was observed in all populations at the Western Victorian and Southern Tablelands sites. Response to selection was absent and persistence was very low under higher temperature and drought stress on the North-West Slopes. This high level of genotype × environment interaction for persistence was also observed among final generation families. Families with better persistence than current winteractive cultivars at the two southern sites were identified in each population and a new cultivar is being formed from the parents.

Farmer experience with perennial pastures in the mixed farming areas of southern New South Wales: on-farm participatory research investigating pasture establishment with cover-cropping

2014 ◽  
Vol 65 (10) ◽  
pp. 973 ◽  
Author(s):  
A. D. Swan ◽  
M. B. Peoples ◽  
R. C. Hayes ◽  
G. D. Li ◽  
G. R. Casburn ◽  
...  
Keyword(s):  
Cover Crop ◽  
New South ◽  
New South Wales ◽  
Annual Rainfall ◽  
Individual Species ◽  
Cover Cropping ◽  
Mixed Farming ◽  
South Wales ◽  
Average Annual Rainfall ◽  
On Farm

In 2009, 95 farmers in the mixed farming zone of southern New South Wales (NSW), average annual rainfall 450–700 mm, were surveyed about their use of perennial pasture species. Survey responses indicated that, on average, 52% of land was under crop, 29% contained perennial pasture and 19% annual pastures. The proportion of land sown to perennial pastures and the species used differed with rainfall. Farmers identified concerns about the cost of establishment and poor survival of perennial pasture species as constraints to wider adoption. The survey also revealed that cover-cropping (sowing pasture species under the final grain crop in a cropping phase) was the dominant method of pasture establishment. Large-scale, on-farm participatory experiments were sown with the farm machinery, three at Ariah Park and one at Brocklesby in southern NSW in 2009 (annual rainfall 100 mm less than long-term average), and a further two experiments (one at each location) commenced in 2010 (annual rainfall >200 mm above average). These experiments compared the effect of cereal cover-crop sowing rate (standard rates used by the collaborating farmer and half of the standard rate) on the establishment of the perennials lucerne (Medicago sativa), phalaris (Phalaris aquatica), cocksfoot (Dactylis glomerata), and chicory (Cichorium intybus) sown in different mixes and rates with various annual legume species. The persistence and productivity of individual species were monitored for 2 years after sowing. Results indicated little or no effect of the presence of a cover-crop on the initial establishment of any of the perennials, but pasture species survival were severely affected by cover-crop sowing rates as low as half of the farmer practice (10 kg barley or 12 kg wheat ha–1) in 2009. Despite higher than average annual rainfall in 2010 and 2011, the residual effect of establishing pastures under a cover-crop in 2009 was poorer persistence and lower productivity by lucerne at the standard cover-cropping rate, and by phalaris, cocksfoot and chicory at all cover-crop rates, and an increased incidence of weeds. Similar responses to cover-cropping occurred between 2010 and 2012, even with the wetter establishment conditions in 2010, for phalaris, chicory and weeds, despite demonstration at Ariah Park that higher populations of individual perennial species could be achieved by doubling the sowing rate of pasture seed in 2010. Lucerne compensated for lower plant numbers by increasing herbage growth in response to rainfall, but phalaris could not and total pasture productivity over the first 2 years after establishment was greatly reduced by the use of cover-crops in both 2009 and 2010. Cover-cropping also reduced annual legume seedset, which could have implications for future pasture performance. Lucerne was the most consistently productive perennial pasture species evaluated regardless of establishment technique or climatic conditions.

Plant cover and composition in relation to density of Callitris glaucophylla (white cypress pine) along a rainfall gradient in eastern Australia

2005 ◽  
Vol 53 (6) ◽  
pp. 545 ◽  
Author(s):  
W. A. Thompson ◽  
D. J. Eldridge
Keyword(s):  
Plant Cover ◽  
Tree Cover ◽  
Annual Rainfall ◽  
Rainfall Gradient ◽  
Understorey Vegetation ◽  
Eastern Australia ◽  
Average Annual Rainfall ◽  
Callitris Glaucophylla ◽  
Understorey Plants ◽  
Cypress Pine

Despite the widespread distribution of Callitris glaucophylla J.Thompson & L.Johnson (white cypress pine) over large areas of eastern Australia, little is known about its impact on the diversity and cover of understorey plants. We examined C. glaucophylla woodlands to see whether stand density and land management influenced the cover and composition of the understorey vegetation. The cover and diversity of understorey plant communities were measured at 83 sites along a gradient in average annual rainfall (215–532 mm) in eastern Australia. The diversity and cover of understorey plants and the cover of trees increased, and the composition of the understorey community changed with increases in average annual rainfall. There were no clear relationships, however, between tree cover or density, and the cover or diversity of understorey plants. Sites that had not been logged contained significantly greater proportions of native and perennial vascular plants, and sites with extant eucalypts had a significantly higher proportion of shrubs than those sites without eucalypts. We attributed these differences to past forestry disturbance regimes which are correlated with the presence of mature eucalypts. Our results do not support the proposition that dense stands of C. glaucophylla suppress the understorey vegetation.

Dawn Water Potential and Root Depth of Trees and Understorey Species in Southwestern Australia

1988 ◽  
Vol 36 (6) ◽  
pp. 621 ◽  
Author(s):  
DS Crombie ◽  
JT Tippett ◽  
TC Hill
Keyword(s):  
Water Potential ◽  
Annual Rainfall ◽  
Soil Profiles ◽  
Seasonal Patterns ◽  
Summer Drought ◽  
Root Depth ◽  
Jarrah Forest ◽  
Southwestern Australia ◽  
Water Potentials ◽  
Average Annual Rainfall

Water relations of selected tree and understorey species in the jarrah forest of south-western Australia were studied during summer drought and the results related to root morphology. Seasonal patterns of predawn water potential (Ψp) differed between species according to root depth and between sites according to average annual rainfall. Dawn water potentials fell most rapidly and by the greatest amount in plants with the shallowest roots. Dawn water potentials of medium and deep rooted species were not consistently different. Separation of Ψp between sites of different annual rainfall was less marked than was separation by root depth. Changes in Ψp, were consistent with a top-to-bottom drying of the soil profiles. We suggest that measurements of Ψp of plants of appropriate root depth can be used to monitor the drying of soils as an alternative to more expensive mechanical and electrical methods.

Biomass, Nutrient Content and Growth Response to Fertilisers of Six-year-old Eucalyptus globulus Plantations at Three Contrasting Sites in Gippsland, Victoria

1997 ◽  
Vol 45 (1) ◽  
pp. 103 ◽  
Author(s):  
L. T. Bennett ◽  
C. J. Weston ◽  
P. M. Attiwill
Keyword(s):  
Eucalyptus Globulus ◽  
Sandy Loam ◽  
Nutrient Content ◽  
Annual Rainfall ◽  
Above Ground Biomass ◽  
Ground Biomass ◽  
P Content ◽  
Eastern Australia ◽  
Treatment Responses ◽  
Establishment Phase

Factorial combinations of three rates of N (up to 400 kg ha-1 elemental) and four rates of P (up to 200 kg ha-1) were applied during the establishment phase of Eucalyptus globulus Labill. plantations on three contrasting sites in Gippsland, south-eastern Australia. Mean annual increments of volume at 71 months ranged from 8 m3 ha-1 year-1 in control treatments on a duplex sandy loam (annual rainfall 850 mm) and a uniform sand (620 mm rainfall) to 23 m3 ha-1 year-1 at the highest combined additions of N and P on a gradational clay loam (1000 mm rainfall). Volumes to 71 months were greatest at the highest combined additions of N and P on the uniform and gradational soils, but significant effects of N and P additions were not sustained on the duplex soil, where the availability of K was limiting after 45 months. Trees were sampled for above-ground biomass and nutrient content at 6 years from four treatments involving the highest additions of N and P and treatment responses were interpreted using vector analysis. The greater magnitude of P vectors than N vectors at all sites indicated that P additions, in particular, were important for good early growth. However, relationships between above-ground biomass and P content indicated accumulation of P in excess of growth requirements and reduced efficiency of P additions at the highest rates. The paper concludes with general recommendations for fertiliser additions during the establishment phase of E. globulus plantations.

Summer drought survival and recovery in Microlaena stipoides

2016 ◽  
Vol 38 (5) ◽  
pp. 501 ◽  
Author(s):  
M. L. Mitchell ◽  
J. M. Virgona ◽  
J. L. Jacobs ◽  
D. R. Kemp
Keyword(s):  
Soil Water ◽  
Moisture Stress ◽  
Pot Experiment ◽  
Summer Drought ◽  
Water Deficits ◽  
North East ◽  
Eastern Australia ◽  
Summer Dormancy ◽  
Microlaena Stipoides ◽  
Summer Storm

Microlaena stipoides (microlaena) is an important perennial grass in over 7 million hectares of native pastures in southern Australia and can survive and persist despite severe soil water deficits during summer. Many other pasture species survive similar conditions by relying on summer dormancy, which raises the possibility that microlaena may behave similarly. A field experiment using rainout shelters was conducted on an existing microlaena pasture in north-east Victoria. The experiment was a split-plot design with two watering treatments (‘summer storm’ or ‘summer dry’) as main plots and three defoliation treatments (nil, intense defoliation, strategic defoliation) as subplots. The ‘summer storm’ treatment resulted in the formation of new buds and tillers and increased basal cover from 1% in February to 18% in March. A glasshouse pot experiment examined the recovery of microlaena after different periods of drought and subsequent rewatering. In the pot experiment, microlaena withstood relatively short (up to 30 days) dry periods and then recovered when rewatered. Thus, it appears that microlaena is a persistent, perennial pasture plant that, although it survives very dry summers in Mediterranean areas, is not summer dormant. Microlaena does not exhibit summer dormancy in response to moisture stress and enter a quiescent stage, because normal growth is prevented by the lack of water, but it quickly recommences growth when soil water becomes available. The ability of microlaena to withstand summer soil water deficits and to recruit from seedlings make it a valuable pasture species across drought-prone environments, and this undoubtedly partly explains its very broad adaptation across eastern Australia.

THE ROLE OF GRASSLAND IN MANAGEMENT

1968 ◽  
pp. 44-49
Author(s):  
B.K. Cameron
Keyword(s):  
Soil Temperature ◽  
Annual Rainfall ◽  
Silt Loam ◽  
Average Annual Rainfall ◽  
Very High ◽  
Wilting Point

THE PROPERTY to be discussed is a mixed sheep and cropping unit, situated ei ht a miles east of Ashburton and midway between the Ra aia and the Ashburton rivers. Average annual rainfall is 27 in., evenly spread, but there is very high summer evaporation and therefore frequent droughts. On average, the soil is below wilting point for 40 to 50 days each summer. Winters are cold with the soil temperature being below 48°F for about four months each year. The soil is a Lismore stony silt loam averaging 9 in. in depth over gravel.

Application of physiological understanding in soybean improvement. I. Understanding phenological constraints to adaptation and yield potential

2011 ◽  
Vol 62 (1) ◽  
pp. 1 ◽  
Author(s):  
R. J. Lawn ◽  
A. T. James
Keyword(s):  
Seed Yield ◽  
Environmental Control ◽  
Thermal Environment ◽  
Sowing Date ◽  
Companion Paper ◽  
Interaction Effects ◽  
Yield Potential ◽  
Environment Interaction ◽  
Sowing Dates ◽  
Eastern Australia

The purpose of this paper and its companion1 is to describe how, in eastern Australia, soybean improvement, in terms of both breeding and agronomy, has been informed and influenced over the past four decades by physiological understanding of the environmental control of phenology. This first paper describes how initial attempts to grow soybean in eastern Australia, using varieties and production practices from the southern USA, met with limited success due to large variety × environment interaction effects on seed yield. In particular, there were large variety × location, variety × sowing date, and variety × sowing date × density effects. These various interaction effects were ultimately explained in terms of the effects of photo-thermal environment on the phenology of different varieties, and the consequences for radiation interception, dry matter production, harvest index, and seed yield. This knowledge enabled the formulation of agronomic practices to optimise sowing date and planting arrangement to suit particular varieties, and underpinned the establishment of commercial production in south-eastern Queensland in the early 1970s. It also influenced the establishment and operation over the next three decades of several separate breeding programs, each targeting phenological adaptation to specific latitudinal regions of eastern Australia. This paper also describes how physiological developments internationally, particularly the discovery of the long juvenile trait and to a lesser extent the semi-dwarf ideotype, subsequently enabled an approach to be conceived for broadening the phenological adaptation of soybeans across latitudes and sowing dates. The application of this approach, and its outcomes in terms of varietal improvement, agronomic management, and the structure of the breeding program, are described in the companion paper.

Wind blown sediment mass budget of Sahelian village land units in Niger

2001 ◽  
Vol 172 (5) ◽  
pp. 523-531 ◽  
Author(s):  
Jean-Louis Rajot
Keyword(s):  
Wind Erosion ◽  
Size Range ◽  
Arable Land ◽  
Annual Rainfall ◽  
Complete Disappearance ◽  
Mass Budget ◽  
Sediment Mass ◽  
Aeolian Sediments ◽  
Average Annual Rainfall ◽  
The Village

Abstract To assess the mass budget of aeolian sediments transported by wind (erosion vs. deposition) at the scale of village land units (25 kmX25 km), measurements were carried out during 3 years (from 1996 to 1998) in a cultivated field and in a fallow area simultaneously. These were located in the Sahelian zone of Niger with an average annual rainfall of 560 mm. The vertical upward fluxes of particles <20 mu m exported from the study area were estimated from the horizontal sediment fluxes measured using BSNE sand catchers. This mass of exported dust was compared with the vertical downward fluxes of particles of the same size range (<20 mu m) measured using passive CAPYR collectors. Values of deposition recorded in the field and in the fallow were similar. In the field, wind erosion reached its maximum in May and June when the vegetation cover was minimal. In the fallow area, wind erosion was always very low in comparison with the field. It occurred during the strongest storms when the grass cover was minimal. Nevertheless, the net balance between deposition and erosion was highly positive in the fallow areas. These results have been extrapolated at the scale of the village land units based on the current land use. At this scale, the balance was positive for the arable land, indicating a net deposition of aeolian sediments of +0.36 t ha (super -1) yr (super -1) . However, the complete disappearance of fallow land would result in a balanced budget for the arable land.

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