This is one of 8 Biocontrol Profiles. It introduces the topic of biocontrol and deals with the commercial use of the milky disease bacterium Bacillus popilliae to. Paenibacillus popilliae. (Eubacteriales: Bacillaceae). formerly Bacillus popilliae. Milky Disease. The Japanese beetle, Popillia japonica, was accidentally. Spore formation by Bacillus popilliae in liquid medium containing activated carbon. J. Bacteriol. – —Heretofore, it has not been found.
|Published (Last):||17 May 2016|
|PDF File Size:||9.88 Mb|
|ePub File Size:||18.92 Mb|
|Price:||Free* [*Free Regsitration Required]|
This is one of popilkiae Biocontrol Profiles. It introduces the topic of biocontrol and deals with the commercial use of the milky disease bacterium Bacillus popilliae to control the Japanese beetle, a serious pest of turf, fruit crops and garden ornamentals in the USA. Biology and Control of Crown gall Agrobacterium tumefaciens Bacillus thuringiensis Control of Heterobasidion root rot of pine Biology and control of take-all disease Catenaria anguillulaea parasite of nematodes Pythium oligandrum and other mycoparasites Fungal tip growth and hyphal tropisms.
Natural environments tend to be balanced environments, where organisms depend on one another and also constrain one another by competition for resources or by parasitism, predation, etc. But human influences can upset these balances, and this is most evident when an baciillus organism is introduced on purpose or by accident.
Many of the most serious pests, crop diseases or invasive weeds are the result of “introductions” from foreign lands.
The newly introduced organisms find a favourable environment, free from their previous constraints, and they proliferate to achieve “pest” status. Entomologists has bacilluw useful term for this – they refer to the constraining organisms in the region of origin as “the natural enemy complex”. In other words, biocontrol is both a naturally occurring process which we can exploit and the purposeful use of one organism to control another.
In practice, biocontrol can be achieved by three methods. In this section we discuss the use of a bacterium, Bacillus popilliaeto control a major introduced pest in the USA. Much of the text below has been copied and updated from a book now out of print [JW Deacon, Microbial Control of Plant Pests and Diseases.
Van Nostrand Reinhold, Wokingham]. Although it is not a problem in its area of origin, the beetle causes serious damage in the USA. It spread rapidly from the initial sightings in New Jersey and today it is found over roughly half of the country, in almost every state east of the Mississippi.
It is a problem as an adult beetle because it feeds on a wide range of plants, eating out the leaf tissues between the leaf veins Figure Band it accumulates on ripening fruit causing substantial damage. It is also a problem ppilliae the larval stage because the adult beetles lay their eggs in grass turf and the grubs destroy the grass roots, bafillus on new housing estates where natural enemies are absent.
Adult Japanese beetles, about cm long.
Bacillus popilliae | bacterium |
Figure Bfeeding damage on foliage. Based on slides provided by Fairfax Biological Laboratory. All these bacteria are specialised pathogens of beetles Coleopteraspecifically of the scarabaeid beetles family Scarabaeidae. This family includes the beneficial dung beetles but also some of the most important pasture pests – the chafers. The milky disease bacteria are highly pathogenic and also highly persistent in the environment so they can be used for mass release to achieve lasting control.
It is a fastidious organism that grows only on rich media containing yeast extract, casein hydrolysate or an equivalent amino acid source, and sugars. Several amino acids are known to be required for growth, as are the vitamins thiamine and barbituric acid. Trehalose, the sugar found in insect haemolymph, is a favoured carbon source though glucose also can be used. Some varieties of B. But the crystal is not thought to play a significant role in infection and certainly it is not as important as in B.
The variety lentimorbus, for example, does not produce a crystal and yet it causes disease. Another difference between B. Actually there are a number of oligosporogenic mutants – ones that produce a few spores – but spores for microbial control programmes are usually produced in living insect larvae – an expensive and time-consuming process.
The spores germinate in the gut within 2 days and the vegetative cells proliferate, attaining maximum numbers within 3 to 5 days. By this time some of the cells have penetrated the gut wall and begun to grow in the haemolymph, where large numbers of cells develop by day 5 to A few spores also are formed at this stage but in the variety popilliae the main phase of sporulation occurs later and is completed by 14 to 21 days when the larva develops the typical milky appearance.
In laboratory conditions the larva remains alive until this stage and usually contains about 5 x 10 9 spores.
In field conditions, however, there are reports that larvae sometimes die earlier, before the main phase of sporulation is completed. This is of concern because sporulation stops when the host dies and the larva ultimately releases fewer spores to maintain the level of infestation of a site.
Injection of healthy larvae of the Japanese beetle, as the first stage in production of commercial spore powders. The control strategy is aimed solely against the larvae, so if the beetle itself is causing serious damage a chemical insecticide must be used for short-term control. The bacterial spores are produced commercially in larvae collected from grass turf on golf-courses, airports, etc. The larvae are injected with bacterial cells Figures E-Gincubated until they develop a milky appearance and then crushed and dried to give a spore powder Figure H.
The spore powders are applied to turf in small heaps at roughly 1-metre spacing Figures I, J and the spores are then distributed naturally by wind and rain. They can persist in soil for several years and infect larvae that eat them. Therefore they have the potential to give lasting control of a pest problem, because the spore numbers in soil are boosted periodically when a diseased larva dies.
Commercial “milky poilliae powders are marketed under several names, by several companies. For example, Fairfax Biologicals markets its product under the trade name ” Doom “. After the larvae have been injected with B. This powder is applied to the surface of turf Figures I, J where it will be washed into bcaillus ground. The advantages of B. Its disadvantages, however, include 1 the high cost of production in vivo; 2 its slow rate of action; 3 most importantly, its lack of effect on adult beetles which often cause the most obvious and distressing damage, and 4 its relative unattractiveness to the small landowner.
Larval densities ranged from 0 to per square metre of turf in meanand were sometimes as high as those recorded 25 years earlier, before the control programme was begun.
Moreover, in this study only 0. Perhaps there has been a reduction in virulence of B. This might be expected by natural selection, because an obligately pathogenic bacterium that kills its host too rapidly would be at a popillkae disadvantage.
Journal of Economic Entomology 68 Biological Control 4 Scarabaeidae grubs in Kentucky. Journal of Economic Entomology 88 bcaillus, Journal of Bacteriology Here are just a few: Managing the Japanese beetle not on this server.
Biological Control Natural environments tend to be balanced environments, where organisms depend on one another and also constrain one another by competition for resources or by parasitism, predation, etc. We can define Biological control biocontrol as: Inundative release also termed “classical biocontrol” in which a natural enemy of a target pest, pathogen or weed is introduced to a region from which it is absent, to give long-term control of the problem.
An example of this is the use of Bacillus popilliae to control the Japanese beetle in the USA, discussed below. The biopesticide approach in which a biocontrol agent is applied as and when required often repeatedlyin the same way as a chemical control agent is used. Examples of this include the use of Bacillus thuringiensisPhlebiopsis gigantea and Agrobacterium radiobacter.
Management and manipulation of the environment to favour the activities of naturally occurring control agents. An example of this is baccillus in take-all control in grass turf. Control of the Japanese beetle In this section we discuss the use of a bacterium, Bacillus popilliaeto control a major introduced pest in the USA.
By the s the beetle problem had become so serious that a search was begun for a control measure. This led to the discovery of some naturally occurring diseased larvae. The disease was termed milky disease because of the milky white appearance of the grubs, due to a large pkpilliae of refractile bacterial spores in the haemolymph insect blood Figures C, D.
Two types of bacterium were subsequently isolated from two types of milky disease. Type A disease was characterized by a pure white appearance of the grubs and the bacterium in this case was named B. Type B disease differed in that the grubs showed a transition from white to brown over winter and the bacterium causing this disease was named B.
A range of other milky disease bacteria were isolated from beetle hosts throughout the world, but the trend now is to regard all of these as varieties of B.
There was a problem providing the content you requested
Figure Clarvae of the Japanese beetle in soil; the ppopilliae are about cm long. Figure Da healthy grub right and a diseased grub left. The bacterium and its physiology B. The host-parasite interaction B. The cause of insect death is not fully known. Physiological starvation caused by the growth of bacterial cells in the haemolymph seems the most likely explanation, and fat reserves of diseased larvae have been shown to be much reduced compared with those of healthy larvae.
However, toxins also may be involved because they have been detected in culture filtrates of the bacteria and shown to be lethal on injection. Recently, a crystal protein from sporulating cells of B. Nacillus it does not cause such drastic effects on the insect gut wall as do the B. Application for biological control B. The use of B. Between and over tons of spore powder were applied to turf in oversites in the USA as part of a Government programme Fleming, Larval numbers in the turf were reduced to fold and the population stabilized at this new low level, with corresponding reductions in the levels of adult beetle damage.
However, the treatment is most effective when applied on a region- or state-wide basis or at least to relatively large areas to reduce overall the levels of beetle infestation. It is less appropriate for use by small landowners, who may control the larvae in their own turf only to find their trees and shrubs being eaten by beetles from their neighbours’ properties. The success of the control programme must be judged not on this basis but by the fact that over a number of years the mean level of popiloiae damage is lower than it would be in the absence of B.
Advantages and disadvantages of B. Managing the Japanese beetle not on this server Ornamentals and Turf: