scholarly journals Low‐temperature physiology of climatically distinct south African populations of the biological control agent Neochetina eichhorniae

2020 ◽  
Vol 46 (1) ◽  
pp. 138-141
Author(s):  
Daniel J. Rogers ◽  
John S. Terblanche ◽  
Candice A. Owen
Keyword(s):  
Biological Control ◽  
Low Temperature ◽  
South African ◽  
Biological Control Agent ◽  
Control Agent ◽  
African Populations ◽  
Neochetina Eichhorniae ◽  
South African Populations

The pathogenicity of an Australian isolate of Acremonium zonatum to water hyacinth, and its relationship with the biological control agent, Neochetina eichhorniae

1987 ◽  
Vol 38 (1) ◽  
pp. 219 ◽  
Author(s):  
JC Galbraith
Keyword(s):  
Biological Control ◽  
Water Hyacinth ◽  
Biological Control Agent ◽  
Control Agent ◽  
Control Programme ◽  
Australian Isolate ◽  
Free Moisture ◽  
Neochetina Eichhorniae ◽  
Dry Conditions ◽  
The Individual

The first description of Acremonium zonatum on water hyacinth in Australia is made. Its pathogenicity was studied as part of the search for a microorganism already present in Australia which could be developed as a mychoherbicide to supplement the arthropod biological control programme in this country. Following inoculation with A. zonatum, extensive leaf infections developed, favoured by injury and free moisture, but new leaves continued to form. Feeding by the weevil, Neochetina eichhorniae, increased infection by A. zonatum in relatively dry conditions, but it is unlikely that this was due to feeding scars acting as ports of entry. A. zonatum spores were transported on the feet and in the digestive tract of the weevil. The growth of infected plants, estimated by standing crop, was reduced by 49% compared to the control. A further decrease occurred in infected plants infested by weevils, but the total reduction in growth was not equal to the sum of the individual effects of fungus and weevil. Infection did not develop in 15 other plant species inoculated with the Australian isolate of A. zonatum. Although not a virulent pathogen, A. zonatum has some favourable characteristics for consideration as a mycoherbicide and has not appeared antagonistic to N. eichhorniae in these studies. Its role probably lies in exerting a chronic stress on plants already under attack by arthropod biological control agents.

Predisposition of Melaleuca (Melaleuca quinquenervia) to Invasion by the Potential Biological Control Agent Botryosphaeria ribis

Weed Science ◽  
1996 ◽  
Vol 44 (3) ◽  
pp. 603-608 ◽  
Author(s):  
Min B. Rayachhetry ◽  
George M. Blakeslee ◽  
Ted D. Center
Keyword(s):  
Biological Control ◽  
Low Temperature ◽  
Tree Mortality ◽  
Biological Control Agent ◽  
Control Agent ◽  
Melaleuca Quinquenervia ◽  
Xylem Water Potential ◽  
Simulated Drought ◽  
Canker Development ◽  
Low Temperature Treatments

Enhancement of the canker causing ability of Botryosphaeria ribis on melaleuca was studied with respect to stress from simulated drought, low temperature, and defoliation treatments. Low xylem water potential was related to increased level of canker development and subsequent tree mortality. Canker development was enhanced by low temperature treatments with alternating exposure to 6 C for 3 d followed by 4 d at 30 (±5) C for 8 wk. Partial defoliation did not affect canker development but complete defoliation of B. ribis-inoculated ramets resulted in tree mortality within 4 wk. Callusing of melaleuca wounds was either reduced or prevented in stressed trees. These observations suggest that stress induced on the tree enhances the tree-killing efficacy of this fungus.

Biology and climatic requirements of Perapion antiquum (Coleoptera: Apionidae) in southern Africa: implications for the biological control of Emexspp. in Australia

1992 ◽  
Vol 82 (3) ◽  
pp. 399-406 ◽  
Author(s):  
John K. Scott
Keyword(s):  
Biological Control ◽  
South African ◽  
Potential Distribution ◽  
Biological Control Agent ◽  
Control Agent ◽  
Climatic Conditions ◽  
Western Cape ◽  
Western Cape Province ◽  
Southern Half ◽  
Successful Control

AbstractThe potential distribution of the South African weevil, Perapion antiquum (Gyllenhal), a biological control agent for the weeds Emex spp., was deter mined by the computer program CLIMEX, using its native distribution, phenology and abundance together with development parameters. The predicted distribution included parts of Hawaii where the weevil successfully controlled Emex australis and E. spinosa. In Australia, sites of past unsuccessful releases have climates that this analysis indicates are unsuitable for the insect. The most favourable regions for establishment of the weevil are near the coast in the southern half of Australia, but most of these do not overlap with regions where Emex spp. are a problem. In western Cape Province, South Africa, E. australis plants are abundant and the weevil attacks the plant after seeds have formed. In Hawaii, a fortuitous combination of climatic conditions favours the weevil during the period after seed germination, and this may be the key to its control of the weed. Sites with climatic conditions similar to successful control sites in Hawaii are not found in Australia. It was concluded that P. antiquum will be of limited use as a biological control agent in Australia even in areas suitable for its establishment.

scholarly journals Chevroned Water Hyacinth weevil Neochetina bruchi Hustache (Insecta: Coleoptera: Curculionidae)

EDIS ◽  
2021 ◽  
Vol 2021 (2) ◽  
pp. 6
Author(s):  
Eutychus Kariuki ◽  
Carey Minteer
Keyword(s):  
United States ◽  
Biological Control ◽  
Water Hyacinth ◽  
Gulf Coast ◽  
Biological Control Agent ◽  
The United States ◽  
Control Agent ◽  
Weed Biological Control ◽  
Invasive Aquatic Plant ◽  
Neochetina Eichhorniae

Neochetina bruchi Hustache is commonly referred to as the chevroned water hyacinth weevil and is a weed biological control agent used to manage water hyacinth, Pontederia crassipes Mart. [formely Eichhornia crassipes (Mart.) Solms (Pellegrini et al. 2018)], in more than 30 countries (Winston et al. 2014). Imported from Argentina, the insect was first introduced into the United States in Florida in 1974 and released in Louisiana later in 1974 (Manning 1979), Texas 1980, and California 1982 to 1983 (Winston et al. 2014). Now Neochetina bruchi occurs throughout the Gulf Coast States (Winston et al. 2014). The target weed of Neochetina bruchi, water hyacinth, is an invasive aquatic plant in the United States and is included on Florida’s list of prohibited aquatic plants. Neochetina bruchi is among four species of insect biological control agents that have been introduced into the United States to manage water hyacinth. The other three species include a weevil, Neochetina eichhorniae; a moth, Niphograptaalbiguttalis; and a planthopper, Megamelus scutellaris, which were introduced into the United States in 1972, 1977, and 2010, respectively (Tipping et al. 2014). Although the larvae and pupae of Neochetina bruchi and Neochetina eichhorniae have similar appearance and behavior and can be difficult to differentiate by casual observation (Deloach and Cordo 1976), the adult stages of the two species of water hyacinth weevils can be distinguished relatively easily based on the color patterns on their elytra (hardened fore wings).

The Introduction of Bdellodes Lapidaria (Acari: Bdellidae) From Australia Into South Africa for the Biological Control of Sminthurus Viridis (Collembola).

1974 ◽  
Vol 22 (4) ◽  
pp. 505 ◽  
Author(s):  
MMH Wallace ◽  
MC Walters
Keyword(s):  
South Africa ◽  
Biological Control ◽  
South African ◽  
Western Australia ◽  
Biological Control Agent ◽  
Subterranean Clover ◽  
Immediate Release ◽  
Control Agent ◽  
Clover Seed ◽  
Methods Of Control

The lucerne flea, S, viridis, was introduced into South Africa with subterranean clover seed imported from Western Australia in 1939. By 1959 the infestation had spread over 50,000 ha and methods of control were examined. The predatory mite B. lapidaria was known to be an effective biological control agent against S. viridis in Australian pastures. From 1963 to 1966 over 75,000 mites were collected in Western Australia and sent by air for immediate release in selected sites in South Africa (Cape Province). The mites were shown to be established in 1965 and multiplied rapidly, enabling redistribution to additional sites. The influence of this predator on S. viridis numbers is now being monitored. Preliminary data indicate that B. lapidaria is capable of influencing flea densities under South African conditions. A definite relationship between the predator and sminthurid Collembola such as S. viridis slnd Bourletiella arvalis is indicated, although B. lapidaria appears to be able to utilize other foods during periods of sminthurid scarcity.

Sign in / Sign up

Export Citation Format

Share Document