scholarly journals Biological control of ragwort does sheep grazing affect ragwort flea beetle

2000 ◽  
Vol 53 ◽  
pp. 54-58
Author(s):  
K. Betteridge ◽  
P.G. McGregor ◽  
D.A. Costall ◽  
P.G. Peterson
Keyword(s):  
Biological Control ◽  
New Zealand ◽  
Flea Beetle ◽  
Sheep Grazing ◽  
Longitarsus Jacobaeae

Ragwort flea beetle (Longitarsus jacobaeae) (RFB) is present in many parts of New Zealand Its impact on ragwort mortality both alone and on ragwort trimmed to simulate sheep grazing was investigated Trimming reduced ragwort size and biomass throughout the trial More plants died in spring and summer but fewer plants died over the 12 month period in trimmed than untrimmed treatments Trimmed ragwort had fewer RFB larvae/g DM than untrimmed ragwort on only 1 of 3 occasions RFB at 123 RFB larvae/g DM in August did not affect ragwort mortality Low larval numbers were probably a result of high ragwort densities (up to 36/m2)

Herbicides compromise biological control of ragwort

2002 ◽  
pp. 147-152
Author(s):  
K. Betteridge ◽  
D. Costall
Keyword(s):  
Biological Control ◽  
Pyrrolizidine Alkaloids ◽  
Animal Health ◽  
Flea Beetle ◽  
Dairy Farm ◽  
Senecio Jacobaea ◽  
Longitarsus Jacobaeae ◽  
High Ester ◽  
Low Levels

In spite of ragwort flea beetle (RFB) being present on a Dannevirke dairy farm, pastures were sprayed each winter to reduce ragwort density and limit the risk of ragwort poisoning of stock. The trial on this farm from June 1999 - October 2001, aimed to determine whether herbicide (H) impacted on RFB and how H and RFB each impacted on ragwort growth and persistence. RFBfree areas were created by spraying with insecticide (I). Effects of ragwort on animal health are also reported. High ester 2,4-D (H) boom-sprayed once only, in June 1999, killed most ragwort plants and reduced RFB larvae densities to low levels before the plants died. Once new ragwort established in treatment H, the plants became infested with RFB larvae. RFB larvae were suppressed by I resulting in ragwort density declining more slowly than in treatments where RFB were not suppressed. Insecticide treatments were stopped after 15 months and, at 24 months, ragwort could not be found within the trial area. Ragwort control was attributed to the cessation of herbicide spraying allowing the RFB population to reach a sufficient density to kill both small and large ragwort plants. Sub-clinical ragwort poisoning was found in livers of culled cows that had grazed on ragwort-dense pastures. Keywords: animal health, biological control, Longitarsus jacobaeae, pyrrolizidine alkaloids, ragwort, ragwort flea beetle, Senecio jacobaea

THE PERFORMANCE OF S170 TALL FESCUE IN CANTERBURY

1974 ◽  
pp. 214-215
Author(s):  
B.R. Watkin
Keyword(s):  
New Zealand ◽  
White Clover ◽  
Tall Fescue ◽  
Trifolium Repens ◽  
Festuca Arundinacea ◽  
Sheep Grazing ◽  
Selection Of

AN Aberystwyth selection of tall fescue (Festuca arundinacea Schreb.), known as S170, was sown with certified New Zealand white clover (Trifolium repens) and re' clover (T. pratense) and compared under sheep grazing with other grass/clover pastures at the Grasslands Division Regional Station at Lincoln (Watkin, 1975) .

The introduction of the eleven-spotted ladybird Coccinella undecimpunctata to New Zealand in 1874: the first use of a ladybird for biological control, or a spurious record created by cumulative misreporting?

2013 ◽  
Vol 40 (2) ◽  
pp. 277-293 ◽  
Author(s):  
R. A. Galbreath ◽  
P. J. Cameron
Keyword(s):  
Biological Control ◽  
New Zealand ◽  
Historical Records ◽  
Entomological Society ◽  
Beneficial Insects ◽  
Coccinella Undecimpunctata

The introduction of the eleven-spotted ladybird Coccinella undecimpunctata to New Zealand in 1874 has been widely quoted as the first importation of an insect for biological control in New Zealand and one of the first anywhere. However, searches of historical records show no evidence that such an introduction was made or attempted. Instead, there is clear evidence that the presently accepted record arose by a process of cumulative misreporting. An account of discussions in the Entomological Society of London in December 1873 about possible introductions of various beneficial insects to New Zealand was misreported by the American entomologist C. V. Riley, and several subsequent authors restated his version with further modifications and additions. This created the record of the introduction of C. undecimpunctata to New Zealand in 1874 that has been accepted and repeated ever since.

Further Biological Notes on Rhyssa and Ibalia, parasitising Sirex cyaneus, Fabr.

1928 ◽  
Vol 19 (3) ◽  
pp. 317-323 ◽  
Author(s):  
J. G. Myers
Keyword(s):  
Biological Control ◽  
New Zealand ◽  
P 75

The biology of Rhyssa persuasoria, L., and of Ibalia leucospoides, Hochenw., has already been sketched in a preliminary paper published in this Bulletin (xix, pp. 67–77, pl. iii, 1928) in collaboration with Mr. R. N. Chrystal, of the Imperial Forestry Institute. The following observations were made by the writer chiefly at the Farnham House Laboratory, during the spring and summer of 1928, and are gathered together in view of his departure from England. The work of collecting and rearing supplies of Rhyssa and Ibalia for shipment to New Zealand, for the biological control of Sirex nodilio (juvencus), has been continued on a larger scale. The present notes were made incidentally during this work and are arranged under nearly the same headings as in the previous paper, to which they are supplementary. One error needs correcting. It was stated (on p. 75) that the larch (Larix europaea, D.C.) is indigenous, though actually planted in the Oxford locality mentioned. As a matter of fact, of course, larch, though Palaearctic, is not indigenous to Britain.

Biological control of sapstain fungi with natural products and biological control agents: a review of the work carried out in New Zealand

2002 ◽  
Vol 106 (2) ◽  
pp. 228-232 ◽  
Author(s):  
Joël L. Vanneste ◽  
Robert A. Hill ◽  
Stuart J. Kay ◽  
Roberta L. Farrell ◽  
Patrick T. Holland
Keyword(s):  
Biological Control ◽  
Natural Products ◽  
New Zealand ◽  
Biological Control Agents

Opportunities for developing value-added brassica seed

2010 ◽  
Vol 14 ◽  
pp. 139-146
Author(s):  
Van De Jong ◽  
B.E. Braithwaite ◽  
T.L. Roush ◽  
A. Stewart ◽  
J.G. Hampton
Keyword(s):  
Biological Control ◽  
New Zealand ◽  
Xanthomonas Campestris ◽  
Cultural Practices ◽  
Effective Means ◽  
Value Added ◽  
Primary Source ◽  
Common Disease ◽  
Black Rot ◽  
Crop Losses

New Zealand produces approximately 5,500 tonnes of brassica seed per year, two thirds of which, valued at $13M, is exported. Black rot caused by Xanthomonas campestris pv. campestris is a common disease of brassicas, and while crop losses are not extensive in New Zealand, internationally total crop losses have been reported. Seeds are the primary source of inoculum and the ease with which this inoculum spreads means that even small traces can cause severe epidemics. Genetic resistance to black rot is a complex trait which makes breeding for resistance in brassicas challenging. The effectiveness of chemical and cultural practices is variable. Biological control with natural antagonistic microbes may provide a more effective means of controlling black rot and other pests and diseases, and create opportunities for increasing the export value of brassica seed. Current cultural practices and the potential for biological control for the management of black rot are reviewed. Keywords: biocontrol, Brassicaceae, crucifer

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