Seed dispersal and germination in Romulea rosea (onion grass)

Eddy, J.; Df, Smith

doi:10.1071/ea9750508

Cited by 8 publications

(14 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Seed passage reduced overal germination from about 40% to 10% in fistulated sheep, and from about 30% to 1% in grazing sheep. Eddy and Smith (1975) similarly reported a greater depression in germinability of Romulea rosea after passage through grazing than fistulated sheep, and suggested one cause may have been slower passage under grazing conditions. These reductions in germinability were probably due to embryo mortality (Williams & Elliot, 1960) and, perhaps, thermo-dormancy (Barton, 1965Evenari, 1965) because of the relatively high temperature and the low pH in the rumen.…”

Section: Discussionmentioning

confidence: 96%

Dispersal of Echium plantagineum L. by sheep

Piggin¹

1978

Weed Research

View full text Add to dashboard Cite

Summary: Résumé: Zusammenfassung E. ptantagineum L., a native of the Mediterranean regions, has become widespread in the southern and eastern states of Australia since it was introduced as a garden species around the 1850s. It is an annual reproducing entirely by seed. This paper investigates the role of sheep in dispersing the plant. Sheep grazing in the field ate considerable quantities of seed of E. ptantagineum. Studies on fistulated sheep suggested that about 50% of ingested seeds were destroyed by digestion, and many would also have been destroyed by mastication. The rest (c. 120 seeds/sheep/day) were passed intact in the faeces. Most seeds were passed within three days of ingestion, and the number passed each day fell rapidly after ingestion ceased. Germinability of seed fed to the sheep and of seed passed within 24 h of ingestion was similar (40%) for fistulated sheep. Germinability fell rapidly as seed took longer than 24 h to pass, and this was probably more an effect of the high temperature, rather than digestion, in the alimentary tract. Seed that passed through grazing sheep had a much lower germinability (1–2%). Stock grazing on pastures containing seeding E. ptantagineum have probably been responsible for much of the spread of the plant in Australia. The fact that most seed, and all germinable seed, is passed within 3 days of ingestion means that the spread of E. ptantagtneum can be limited by careful movement of contaminated stock within and between farms and districts. Disperston d'Echium plantagineum L. par tes moutons E. ptantagineum, espéce originaire des régions méditerranéennes s'est répandue dans les états du sud et de l'est de l'Australie depuis son introduction comme espéce de jardins aux environs de 1850. C'est une plante annuelle qui se reproduit uniquement par semences. Cette publication examine le role des moutons dans la dispersion de la plante. Les moutons qui sont élevés dans les pâtures ingéretit des quantités considérables de semences d'E. ptantagineum. Des études faites sur des moutons porteurs de fistules ont suggéré que 50% environ des graines ingérées étaient détruites au cours de la digestion et que beaucoup d'autres devraient aussi avoir été détruites par mastication. Le reste, soit 120 semences par mouton et par jour, passe dans les féces. La plupart des semences sont restées ingérées moins de trois jours et le nombre qui transitent chaque jour est tombe rapidement apres que I'ingestion ait cesse. Le pouvoir germinatif des semences consommées par les moutons et celui des semences ayant séjourné jusquà 24 heures dans leur appareil digestif a été analogue (40%) pour les moutons porteurs de fistules. Le pouvoir germinatif est tombé rapidement lorsque les semences ont mis plus de 24 heures à transiter dans l'animal et ceci est probablement l'effet de la température élevée durant les processus digestifs plutót que celui de la digestion elle‐méme. Les semences transitant a travers des moutons en pâture ont eu un pouvoir germinatif bien inférieur (1 à 2%). Les troupeaux pâtur...

show abstract

Section: Discussionmentioning

confidence: 96%

Dispersal of Echium plantagineum L. by sheep

Piggin¹

1978

Weed Research

View full text Add to dashboard Cite

show abstract

“…Whereas broadleaf weeds can be controlled by selective herbicides, onion grass is difficult to eliminate because of its ability to produce both seed and corms in the soil. Onion grass is a major perennial weed infesting low‐fertility pastures in many regions of southern Australia (Eddy and Smith, 1975); its effective control would considerably improve pasture production, nutritive value and animal performance (Bourke et al. , 2008).…”

Section: Discussionmentioning

confidence: 99%

Impact of deferred grazing and fertilizer on plant population density, ground cover and soil moisture of native pastures in steep hill country of southern Australia

Nie¹,

Zollinger²

2011

Grass and Forage Science

View full text Add to dashboard Cite

The impact of deferred grazing (no defoliation of pastures for a period generally from spring to autumn) and fertilizer application on plant population density, ground cover and soil moisture in a hill pasture (annual grass dominated, with Australian native grasses being the major perennial species) were studied in a largescale field experiment from 2002 to 2006 in southern Australia. Three deferred grazing strategies were used: short-term deferred grazing (no defoliation between October and January each year), long-term deferred grazing (no defoliation from October to the autumn break, that is the first significant rainfall event of the winter growing season) and optimized deferred grazing (withholding time from grazing depends on morphological development of the plants). These treatments were applied with two fertilizer levels (nil fertilizer and 50 kg P ha )1 plus lime) and two additional treatments [continuous grazing (control) and no grazing for year 1]. Deferred grazing increased (P < 0AE05) perennial grass tiller density compared with the control. On average, the tiller density of the three deferred grazing treatments was 27-88% higher than the control. There was a negative (P < 0AE01) relationship between perennial and annual grass tiller density. Fertilizer application increased (P < 0AE05) legume plant density. The densities of annual grasses, legumes, onion grass (Romulea rosea) and broadleaf weeds varied between years, but perennial grass density and moss cover did not. The ground cover of the deferred grazing treatments in autumn was on average 27% higher than the control. Soil moisture differed between treatments at 15-30 cm depth, but not at 0-15 depth over autumn and winter. The results imply that deferred grazing can be an effective tool for rejuvenating degraded native pastures through increases in native grass tiller density and population and through improving farm productivity and sustainability.

show abstract

“…The abundance of seed of R. rosea in the uninvaded sites (up to 1658 seeds m −2 ) is indicative of the ability of its diaspores to invade communities in which the herbaceous flora is dominated by native species. Efficient dispersal, and mechanisms ensuring germination at the appropriate time, such as an ability to avoid germination at false breaks (Eddy & Smith 1975) may explain its distribution. By contrast, seeds of the African annual grass E. longiflora and the African perrenial grass E. erecta were more abundant in the soil seed bank of invaded sites.…”

Section: Life Formmentioning

confidence: 99%

Nitrogen availability and weed invasion in a remnant native woodland in urban Melbourne

2006

View full text Add to dashboard Cite

The woodlands of Studley Park, and the greater Yarra Bend Park, are within 4 km of the centre of the city of Melbourne and total more than 200 ha. Weeds are major contributors to the loss of diversity of native species. We examined the hypothesis that an increase in the availability of nitrogen (N) may be responsible for the increase in weed abundance. In a small field trial, nitrogen availability was greater in areas invaded by weeds and weeds had greater nitrate reductase activity than native species. Both invaded and uninvaded areas were wellsupplied with weed seed, although the composition of the seed bank varied greatly between sites. Diaspores of the weed Romulea rosea were abundant in uninvaded sites while those of Ehrharta erecta and Ehrharta longiflora were abundant in invaded sites. The abundance of weed diaspores suggested that increased N availability may be a precondition for invasion. Formation of a dense litter layer by senescent weeds is likely to promote the capture and retention of N added from anthropogenic sources including air pollution and overland flow from nearby roads and drainage channels.

show abstract

Seed dispersal and germination in Romulea rosea (onion grass)

Cited by 8 publications

References 4 publications

Dispersal of Echium plantagineum L. by sheep

Dispersal of Echium plantagineum L. by sheep

Impact of deferred grazing and fertilizer on plant population density, ground cover and soil moisture of native pastures in steep hill country of southern Australia

Nitrogen availability and weed invasion in a remnant native woodland in urban Melbourne

Contact Info

Product

Resources

About