The narrow-leafed lupin (Lupinus angustifolius L.) as a nitrogen-fixing rotation crop for cereal production. II. Estimates of fixation by field-grown crops

1988 ◽  
Vol 39 (6) ◽  
pp. 1017 ◽  
Author(s):  
DF Herridge ◽  
AD Doyle

Experiments were commenced in 1978 to evaluate the impact of the narrow-leafed lupin (Lupinus angustifolius L.) on production of subsequent wheat crops in the N-infertile, acidic soils of the Pilliga Scrub region of northern New South Wales. There were four sites. Production of lupin dry matter (shoots, roots) ranged from 5.0 (Florida A) to 11.4 t ha-1 (Kamala), reflecting seasonal rainfall and crop management. Lupin seed yields varied between 1.29 (Florida A) and 2.03 t ha-1 (Kamala); at two of the sites, yields were greater than the yields achieved by the adjacent wheat crops. At Spring Creek, the wheat was not harvested for grain due to the extremely poor plant growth. Seasonal profiles of C2H2 reduction by each of the four lupin crops reflected growth characteristics; maximum activity coincided with rapid accumulation of dry mater. Diurnal profiles of C2H2 reduction were unaffected by plant age. Rates peaked around noon after rapidly increasing from minimum pre-dawn levels. Total N2 fixed by each of the lupin crops was estimated by comparing N Yields of the lupin and wheat crops. The various methods used resulted in almost identical estimates of N2 fixation at Kamala (215-218 kg ha-') and Spring Creek (222-228 kg ha-'). Estimates . of N2 fixed by the two Florida crops ranged from 72 to 101 (Florida A) and from 82 to 134 kg ha-' (Florida B). The data indicate that large amounts of N can be fixed by field-grown lupins, amounts well in excess of the quantities of N harvested in the seed.

1976 ◽  
Vol 16 (82) ◽  
pp. 739 ◽  
Author(s):  
BJ Scott ◽  
H Brownlee

Dry matter production and seed yields of a range of annual legumes grown in ungrazed swards were measured between 1966 and 1971 on seven sites in the low rainfall wheatbelt of central western New South Wales. Jemalong and Hannaford barrel medics (Medicago truncatula) were the highest yielding medic cultivars tested. Jemalong medic was slightly superior to Hannaford in dry matter production but seed yields were equal. The short season subterranean clovers (Trifolium subterraneum), Dwalganup and Geraldton, yielded much less dry matter and seed than the medics in most experiments. Although the mid-season subterranean clovers, Woogenellup and Clare, persisted for the duration of our experiments, their production was not as consistent as that of the medics, and plant densities decreased. The rose clovers (T. hirtum), Sirint and Kondinin, the cupped clovers (T. cherleri), Beenong and Yamina, and Snail (M. scutellata) and Paragosa (M. rugosa) medics did not produce satisfactory swards.


1994 ◽  
Vol 34 (6) ◽  
pp. 759 ◽  
Author(s):  
GM Lodge ◽  
MG McMillan

Three experiments were conducted at Tamworth, New South Wales, in 1990-92 to assess the effects of a range of broadleaf and grass herbicides, 6 rates of glyphosate and paraquat + diquat, and 4 rates of 2,4-D amine and diuron on the phytotoxicity, dry matter yield, inflorescence number, and seed yield of established Danthonia (wallaby grass) plants. Phytotoxicity was scored visually on a 0-5 scale (0, no phytotoxicity; 5, 100%). Danthonia dry matter yields were not affected (P<0.05) by any herbicide tested, except glyphosate applied at 2360 g a.i./ha. Phytotoxicity was highest for the glyphosate treatment (1440 g a.i./ha) in that study. All rates of glyphosate, and paraquat + diquat rates >250 + 150 g a.i./ha reduced (P<0.05) inflorescence number compared with the unsprayed control. Paraquat + diquat had no significant effect on seed yield, but glyphosate rates >360 g a.i./ha reduced (P<0.05) seed yield compared with the control. In 1992, no damage was observed on 2,4-D amine treatments and phytotoxicity scores were low (<2) for all diuron treatments. Danthonia inflorescence numbers and seed yields were higher (P<0.05) on plots mown in early spring than on unmown treatments. The lack of effect of herbicides such as diclofopmethyl, simazine, fenoxaprop-ethyl, and diuron on Danthonia dry matter yield, and the low phytotoxicity, indicated that a range of chemicals may be used on established Danthonia swards to control perennial and annual grass weeds. Seed yield was more affected than dry matter yield by herbicide, and paraquat + diquat should be used in preference to glyphosate on seed crops.


1985 ◽  
Vol 25 (1) ◽  
pp. 100 ◽  
Author(s):  
RW Strickland ◽  
RG Greenfield ◽  
GPM Wilson ◽  
GL Harvey

This paper reports variation in phenology, morphology, feeding value and environmental adaptation of 18 accessions of Cassia rotundifolia and one each of C. pilosa and C. trichopoda. There were three major maturity groups within C. rotundifolia and a very large variation in seed size. Dry matter and seed yields were measured at four sites in south-eastern Queensland (Beerwah, Gatton, Gympie and Narayen) and at Grafton in New South Wales. There was significant variation in these attributes between accessions, sites and harvest times. All accessions were adapted to light-textured surface soils but did not tolerate waterlogging, particularly on the clay soil at Gatton. One early-flowering accession (34721) of C. rotundifolia has been released for commercial use because of its general performance over the range of seasons and sites that were sampled in this investigation, and prior experience of its persistence and spread under intermittent grazing at a number of sites in Queensland and the Northern Territory. C. rotundifolia and C. pilosa were acceptable animal feeds, but C. trichopoda had deleterious effects on laboratory rats.


1996 ◽  
Vol 36 (3) ◽  
pp. 299 ◽  
Author(s):  
TS Andrews ◽  
RDB Whalley ◽  
CE Jones

Inputs and losses from Giant Parramatta grass [GPG, Sporobolus indicus (L.) R. Br. var. major (Buse) Baaijens] soil seed banks were quantified on the North Coast of New South Wales. Monthly potential seed production and actual seed fall was estimated at Valla during 1991-92. Total potential production was >668 000 seeds/m2 for the season, while seed fall was >146000 seeds/m2. Seed fall >10000 seeds/m2.month was recorded from January until May, with further seed falls recorded in June and July. The impact of seed production on seed banks was assessed by estimating seed banks in the seed production quadrats before and after seed fall. Seed banks in 4 of the 6 sites decreased in year 2, although seed numbers at 1 damp site increased markedly. Defoliation from mid-December until February, April or June prevented seed production, reducing seed banks by 34% over 7 months. Seed banks in undefoliated plots increased by 3300 seeds/m2, although seed fall was estimated at >114 000 seeds/m2. Emergence of GPG seedlings from artificially established and naturally occurring, persistent seed banks was recorded for 3 years from bare and vegetated treatment plots. Sown seeds showed high levels of innate dormancy and only 4% of seeds emerged when sown immediately after collection. Longer storage of seeds after collection resulted in more seedlings emerging. Estimates of persistent seed banks ranged from 1650 to about 21260 seeds/m2. Most seedlings emerged in spring or autumn and this was correlated with rainfall but not with ambient temperatures. Rates of seed bank decline in both bare and vegetated treatment plots was estimated by fitting exponential decay curves to seed bank estimates. Assuming no further seed inputs, it was estimated that it would take about 3 and 5 years, respectively, for seed banks to decline to 150 seeds/m2 in bare and vegetated treatments.


1995 ◽  
Vol 37 (2) ◽  
pp. 203-217 ◽  
Author(s):  
Michael O'Donnell

Decentralizing industrial relations within New South Wales is a central recom mendation of the Niland Green Paper (1989). Decentralism also represents the cornerstone of the New South Wales government's industrial relations reform agenda enshrined in the New South Wales Industrial Relations Act 1991. To date there has been little analysis of the impact o f this legislative change on industrial relations in the New South Wales public sector. This paper provides a case study that examines the degree to which responsibility for bargaining has been devolved within the Parks and Gardens of the New South Wales Ministry for the Environ ment. It argues that, in contrast to the rhetoric of the New South Wales Act, the central agency presiding over the introduction of enterprise bargaining in the public sector, the Public Employment and Industrial Relations Authority; has been reluctant to delegate responsibility to parties in the workplace.


1999 ◽  
Vol 39 (6) ◽  
pp. 743 ◽  
Author(s):  
J. L. Cooper

Summary. Cotton growers in the Macquarie, Namoi and Gwydir Valleys of New South Wales were surveyed in 1992 to determine what crops are grown in rotation with cotton, how frequently rotation crops are used, and what influences the grower’s choice of rotation system. A total of 155 properties were surveyed, covering 100, 49 and 58% of irrigated cotton produced in the Macquarie, Namoi and Gwydir Valleys, respectively. Although a large part of the 1992–93 cotton crop (61% by area) did not follow a rotation crop, there was widespread interest in rotations and 70% of properties had used rotations. Wheat was by far the most widely grown rotation crop, but there was considerable interest in other crops, especially legumes. The perceived benefits from rotation crops reported by most growers were better soil structure, less disease in following cotton, and more soil organic matter. However, when asked why they preferred certain rotation crops, these factors did not rate highly with growers. Crops that were easy to grow and gave the best financial returns possessed the main features sought in a rotation crop. The greatest problem in growing rotation crops was a lack of irrigation water. It is not surprising that this problem ranked highly because when the survey was conducted, the Namoi and Gwydir Valleys had water allocations of 15 and 0%, respectively. Not having suitable equipment to sow rotation crops was also a problem for 17% of growers, but 10% encountered no problems. The survey also investigated the use of permanent beds and retained hills. These practices have benefits for soil structure, and are almost essential for rotation crops which need to be sown as soon as the cotton is harvested. Over 80% of growers using rotations had adopted some form of permanent beds or retained hills. The benefit which ranked highest was a reduction in costs, followed by less soil compaction. Some growers (44%) who used permanent beds or retained hills had no problems, but handling the trash and keeping the rows straight were of concern to others.


1993 ◽  
Vol 33 (3) ◽  
pp. 299 ◽  
Author(s):  
GM Lodge

Plots sown in 1983 were used to examine the seed production and reserves (residual hardseeds) of 15 annual legumes over 5 years at Tamworth in northern New South Wales. Seed production characteristics were measured in 1983 for these annuals, and for 6 perennial legumes. After the annuals had set seed in 1983, an area of the plots was sprayed to prevent flowering in subsequent years, and the rates of decline in seed reserves were compared with those from areas that seeded annually. Seed yields of the perennials were often significantly lower than those of the annuals except Trifolium glomeratum. Seed yields of T. subterraneum var. subterraneum cvv. Seaton Park and Woogenellup were significantly higher than those of cv. Nungarin and T. subterrarzeum var. brachycalycinum cv. Clare. Seed numbers were lowest for Medicago scutellata cv. Sava among the annual medics, and for Nungarin among subterranean clovers. There was little relationship between the mean number of seeds produced from 1983-86 and maturity grading, and between seed numbers and relative dry matter yield. Seed reserves decreased over 5 years by more than 90% in the sprayed treatments of all species. This decrease was not continuous, with the largest declines occurring from December 1983 to August 1984. In the sprayed treatments of Seaton Park, Woogenellup, and Clare, and in both treatments of Astragalus hamosus cv. Ioman, Vicia dasycarpa var. villosa cv. Namoi, and T. hirtum cv. Hykon, none of the original 1983 seed was recovered in 1987. For the annual medics and Nungarin, the number of residual hardseeds in the sprayed treatments in 1987 was about 3-5% of the seed produced in 1983. From 1983 to 1987, seed numbers in the unsprayed treatments declined by 7040% for the annual medics and by 85-95% for Seaton Park, Woogenellup, and Clare. Long-term persistence of annual medics and Nungarin depended on seed production in most years and the maintenance of a high number of residual hardseeds in the soil. In contrast, the mid- and late-maturing subterranean clovers Woogenellup and Clare had low seed reserves and were dependent on seed production in most years for their continued regeneration.


2018 ◽  
Vol 58 (8) ◽  
pp. 1470
Author(s):  
J. S. Richards ◽  
M. A. Sladek ◽  
G. J. Lee

Reproduction is an important driver of profitability in commercial sheep flocks. Historically, Merino flocks have been run with a fixed age structure, ignoring individual merit and casting for age at a specific age. More recently, research has focussed on utilising the variation within age groups by keeping productive older ewes longer and culling less productive ewes earlier. Previous studies have also examined the effect of age on reproduction and the impact of reproduction status on productivity, but little research has been conducted on cumulative effects of reproductive performance on later productivity, reproduction and health. The present study examined the impact of higher lifetime reproduction on other key production and fitness traits in older ewes run under commercial conditions. Data were collected from two commercial wool-producing properties in the South West Slopes and the Central West Plains of New South Wales during 2009–2011. Reproduction, fleece measurements, bodyweight and condition and dental health were recorded during the study. The results showed that age had a bigger effect on productivity and dental health than did cumulative lifetime reproduction. Environment and genetics determined the level of impact, with minimal loss in productivity from increased age of animals occurring in the South West Slopes flock, whereas the Central West Plains flock would appear to require closer monitoring of productivity as ewes aged. The data collected did not allow separation of the genetic and environmental influences within the study. Retaining animals with a higher reproductive performance past normal culling age does not necessarily result in reduction of productivity or ewe health, but this must be monitored.


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