Biological Control - Science topic

Dr Nabila Benkhelifa thank you for your contribution to the discussion

A wide variety of bacterial genera, including Agrobacterium, Alcaligenes, Arthrobacter, Bacillus, Enterobacter, Erwinia, Pseudomonas, Rhizobium, Serratia, Stenotrophomonas, Streptomyces, and Xanthomonas have been described to have plant disease protection activity against fungal and bacterial pathogens. A common biocontrol agent for control of plant diseases is Trichoderma. Trichoderma is a free-living fungus that is used for foliar application, seed treatment and soil treatment for suppression of various disease-causing fungal pathogens. Biocontrol agents or microbial antagonists prevent infection of the host plant by the pathogen, or establishment of the pathogen in the host plant. The principal mechanisms for the control have been assumed to be those that act primarily upon the pathogens. Microbial biopesticides contain microorganisms as the main active ingredient that function as biological control agents, affecting the pathogen directly or indirectly through the compounds they produce or by stimulating specific plant responses. Biological control agents such as these include predators, parasitoids, pathogens, and competitors. Biological control agents of plant diseases are most often referred to as antagonists. Biological control agents of weeds include seed predators, herbivores, and plant pathogens. Biological control is one of the control measures viz. through the use of microorganisms to suppress the growth and development of bacterial plant pathogen and ultimately reduce the possibility of disease onset. Biopesticides also exist for the management of weeds, insects, and nematodes. While generally a logical fit for managing diseases in organic crops, there are some biopesticides that are NOT approved for organic production. In organic farming, a solution of Azotobacter and synthetic nitrogenase is used to control different insects, weeds, and nematodes. The use of biopesticides protects against fluoroacetamide and other chemicals from contaminating the soil. Additionally, they are less likely to affect both human and animal skin. Bio pesticides are living organisms which can intervene the life cycle of insect pests in such a way that the crop damage is minimized. The agents employed as biopesticides, include parasites, predetors and disease causing fungi, bacteria and viruses, which are the natural enemies of pests.

Biological treatment methods use microorganisms, mostly bacteria, in the biochemical decomposition of wastewaters to stable end products. More microorganisms, or sludges, are formed, and a portion of the waste is converted to carbon dioxide, water, and other end products. A variety of chemicals are available that have been designed to control plant diseases by inhibiting the growth of or by killing the disease-causing pathogens. Chemicals used to control bacteria fungi , and nematodes may be applied to seeds, foliage, flowers, fruit, or soil. A wide variety of bacterial genera, including Agrobacterium, Alcaligenes, Arthrobacter, Bacillus, Enterobacter, Erwinia, Pseudomonas, Rhizobium, Serratia, Stenotrophomonas, Streptomyces, and Xanthomonas have been described to have plant disease protection activity against fungal and bacterial pathogens. Biological control is a method of plant disease management by inhibiting plant pathogens, improving plant immunity, and/or modifying the environment through the effects of beneficial microorganisms, compounds, or healthy cropping systems. So, microbial agents are highly specific against target pests so they facilitate the survival of beneficial insects in treated crops. This may be the main reason that microbial insecticides are being developed as biological control agents during the last three decades.A pathogen is defined as an organism causing disease to its host, with the severity of the disease symptoms referred to as virulence. Pathogens are taxonomically widely diverse and comprise viruses and bacteria as well as unicellular and multicellular eukaryotes. Microorganisms that cause disease are collectively called pathogens. Pathogens cause disease either by disrupting the bodies’ normal processes and/or stimulating the immune system to produce a defensive response, resulting in high fever, inflammation and other symptoms. Biological wastewater treatment method, also known as the conventional method, is a common and widely used method of treatment. It takes into account biodegradation bleaching by taking aid of several micro-organisms, fungi, bacteria, yeasts, and algae.

A wide variety of bacterial genera, including Agrobacterium, Alcaligenes, Arthrobacter, Bacillus, Enterobacter, Erwinia, Pseudomonas, Rhizobium, Serratia, Stenotrophomonas, Streptomyces, and Xanthomonas have been described to have plant disease protection activity against fungal and bacterial pathogens. Biological control is a method of plant disease management by inhibiting plant pathogens, improving plant immunity, and/or modifying the environment through the effects of beneficial microorganisms, compounds, or healthy cropping system.Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also involves an active human management role. First successful classical biological control of a weed (prickly pear) was achieved unintentionally in India when cochineal insect, Dactylopius ceylonicus was mistakenly introduced from Brazil in place of D. cacti to produce dye from Opuntia vulgaris. This incident led to biological control of weeds. The control of the growth of an insect or pest by using a biological agent or living organism. This process is also referred to as biological control. Biocontrol is used to get pest-free fields. It is a very effective and long-term method to remove invasive plants.

Preventive and biological methods are environment friendly, target-specific, do not cause pollution and are harmless to other life forms, they are preferred for it protecting crops. Over expose of chemicals leads to environmental problems hence, biological methods are preferred for protecting crops from pathogens, insects, and rodents along with increasing the production. Biological control is the use of one biological species to reduce populations of a different species. There has been a substantial increase in commercialization of biocontrol products, such as beneficial insects, cultivated predators and natural or non-toxic pest control products. Biological control of insect pests and diseases through biological means is most important component of IPM. In broader sense, biocontrol is use of living organisms to control unwanted living organisms. Biological control is the use of living organisms to suppress pest populations, making them less damaging than they would otherwise be. Natural enemies of insects play an important role in limiting the densities of potential pests. These natural enemies include predators, parasitoids, and pathogens. Regulating the Ecosystem to Protect and Promote Natural Enemies or Competitors of Pathogens. Plant disease often results from a disordered ecosystem [80]. The success of biological control relies on a healthy ecosystem provided by predators, competitors, promoters, and other species.

the main idea is a self-sustaining agroecosystem and control of pests without pesticides.

Microorganism as bacterium, fungus, virus or protozoan as the active ingredient can control many different kinds of pests, although each separate active ingredient is relatively specific for its target pest and there are fungi that control certain weeds, and other fungi that kill specific insects. Some microorganisms contribute to insect nutrition, by providing nutrients or degrading plant material intractable to insect digestion. Resident microorganisms protect their insect hosts against natural enemies, including viruses, bacteria, and parasitoids, by synthesizing toxins or modulating the insect immune system. The bio-agents such as Bacteria- (Bacillus thuringiensis), Fungi (Beauveria, Metarhizium, Verticillium, Nevorium), Virus (NPV), etc are widely used for control of various pests in agriculture. These bioagents will produce non-toxic biological material (protein) which is harmful to pests. There are three primary methods of using biological control in the field: 1) conservation of existing natural enemies, 2) introducing new natural enemies and establishing a permanent population, and 3) mass rearing and periodic release, either on a seasonal basis or inundatively. Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also involves an active human management role. Biological control is a method of plant disease management by inhibiting plant pathogens, improving plant immunity, and/or modifying the environment through the effects of beneficial microorganisms, compounds, or healthy cropping systems. Biological control, the use of living organisms to control pests. A natural enemy such as a parasite, predator, or disease organism is introduced into the environment of a pest or, if already present, is encouraged to multiply and become more effective in reducing the number of pest organisms.

Microorganism abacterium, fungus, virus or protozoan as the active ingredient can control many different kinds of pests, although each separate active ingredient is relatively specific for its target pest. As there are fungi that control certain weeds, and other fungi that kill specific insects. Biological control includes the use of predators, competitors, pathogens and compounds of biological origin. Microorganisms used include viruses, bacteria, fungi and protozoans. These may cause disease, or may compete with or otherwise limit the target organism. Biological controls tend to be highly specific.Biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also involves an active human management role. The soil bacterium Bacillus thuringiensis (Bt) produces endotoxins during sporulation that have specific toxicity to several insect species. The inactive crystal protein is enzymatically converted to an active toxin inside an insect's gut. Alongside the use of disease-resistant cultivars, biological control is seen to have an important role in integrated pest management strategies aimed at reducing the use of chemical pesticides. A BCA is an organism or collection of organisms rather than a chemical per se. regulating the Ecosystem to Protect and Promote Natural Enemies or Competitors of Pathogens. Plant disease often results from a disordered ecosystem. The success of biological control relies on a healthy ecosystem provided by predators, competitors, promoters, and other species. Biological control uses a living organism to kill pests while chemical control uses different strong chemicals to kill, prevent or repel pests. Therefore, biological control is an eco-friendly method since it does not harm the environment and people while chemical control is not environmental friendly.

Biological control is used primarily for controlling pests in crop cultivation. Advantages of biological control are that no artificial substances are added, and that pathogens / animals that develop resistance against biological control agents are rare. There are three primary methods of using biological control in the field: conservation of existing natural enemies, introducing new natural enemies and establishing a permanent population and mass rearing and periodic release, either on a seasonal basis or inundatively. Biological control is particularly desirable because the tactic is environmentally safe, energy self-sufficient, cost-effective, sustainable, and can be readily incorporated into integrated pest management) programs. Furthermore, in many cases benefits from the use of natural enemies accrue at no additional cost. The principal attributes of an effective biological control agent are: efficient searching ability, high parasitism or predation rate, high reproductive potential, minimal handling time, ability to survive at low prey densities and ability to adapt to a wide range of environmental conditions. The most commonly used biopesticides are living organisms, which are pathogenic for the pest of interest. These include biofungicides, bioherbicides and bioinsecticides. Microbes act as biocontrol agents in three ways, either they cause diseases in the pests or compete with them or kill them. Microbial control of insects is the concerted use of insect-specific pathogens and nematodes for the biological control of insects. Microbial pesticides have a number of advantages over conventional chemical pesticides.

Biological control included bacteriotherapy, bacteriophage therapy, malaria therapy, probiotics, and the use of living maggots. In all cases the organisms themselves rather than a product of their metabolism were used as the potentially curative agent. Biological control is a method of plant disease management by inhibiting plant pathogens, improving plant immunity, and/or modifying the environment through the effects of beneficial microorganisms, compounds, or healthy cropping systems. The biological control method involves the use of the living organisms which act as the predators for the pests and harmful insects. The main advantage of the biological control method in the control of agricultural pests is that they are self-perpetuating. Microbes act as biocontrol agents in three ways, either they cause diseases in the pests or compete with them or kill them. Biotechnology has extended widely and has developed many biocontrol agents. Microbial control agents can be effective and used as alternatives to chemical insecticides. A microbial toxin can be defined as a biological toxin material derived from a microorganism, such as a bacterium or fungus. Pathogenic effect of those microorganisms on the target pests are so species specific.

Dear Addisu Sileshi thank you for your contribution to the discussion

I agree with Eslam Mohamed Albastwisi that biological control can be used to regulate numerous types of organisms including insects, mites, spiders, snails, weeds, trees, fungi, algae and even animal by-products. Natural enemies that control plants are actually highly specific plant feeders. Natural control by beneficial insects or other environmental factors happens regardless of whether humans are aware of it or not. Biological control is when humans purposely manipulate populations of beneficial insects to manage undesirable insects. Biological control, the use of living organisms to control pests. A natural enemy such as a parasite, predator, or disease organism is introduced into the environment of a pest or, if already present, is encouraged to multiply and become more effective in reducing the number of pest organisms. Natural controls include effects of natural enemies other biotic factors such as food availability and competition, and abiotic factors such as weather and soil. Biological control is used primarily for controlling pests in crop cultivation. Biological controls are that no artificial substances are added, and that pathogens / animals that develop resistance against biological control agents are rare. Biological control is particularly desirable because the tactic is environmentally safe, energy self-sufficient, cost-effective, sustainable, and can be readily incorporated into integrated pest management (IPM) programs. Biocontrol reduces the pest population and their impacts on the environment and natural enemies are an environmentally friendly alternative to pesticides that are often used to control invasive species. Biocontrol is environmentally friendly because it causes no pollution and affects only the target plant. Self-perpetuating or self-sustaining and therefore permanent and cost-effective.

Secondary metabolites have complex chemical composition and are produced in response to various forms of stress to perform different physiological tasks in plants. They are used in pharmaceutical industries, cosmetics, dietary supplements, fragrances, flavors, dyes, etc. Primary metabolites are compounds that are directly involved in the growth and development of a plant whereas secondary metabolites are compounds produced in other metabolic pathways that, although important, are not essential to the functioning of the plant. Secondary metabolites, at least the major ones present in a plant, apparently function as defence (against herbivores, microbes, viruses or competing plants) and signal compounds (to attract pollinating or seed dispersing animals). They are thus important for the plant's survival and reproductive fitness.

Hi Juan, I would suggest to go with a combined biological control approach. You can try to suppress the pest in soil by using entomopathogenic fungi before or during plantation, and on the leaves/plants/shrubs by spraying botanical pesticides that have a repellent effect (eg: Azadirachta indica commonly known as Neem). Both of them are harmless and alternative to chemical pesticides.

If you use soil from vergin soil, you can't lose any fungal microorganisms in the soil.

Respected sir,

Do you already have the cultures of some common stored grain pests parasitoids , or are you thinking of conducting a survey to find out ? I think it will be very amazing to find out some natural enemies of stored grain pests.

The neem biopesticide can be extracted from the seeds or leaves which are extracted with ethanol.

This material is generally recognized as being non toxic and safe.

In India neem is incorporated in toothpaste I am told.

Neem is a fast growing tree that usually reaches a height of 15-20 m, and under very favorable conditions up to approximately 30-35 m. As a rule it is a evergreen tree, but under extreme circumstances, such as extended dry periods, it may shed most of nearly all of its leaves. The branches spread widely. The fairly dense crown is roundish or oval and may reach a diameter 15-20 m in old free standing specimens. The trunk is relatively short, straight and may reach a girth of 1.5-3.5 m. The bark is hard fissured or scaly and whitish-gray to reddish-brown. The sap wood is grayish-white and the heart wood reddish.

The root system consists of a strong taproot and well developed lateral roots. The lateral surface root may reach over 18 m. Vesicular-arbuscular mycorrhiza (VAM) is associated with the rootlets categorized neem as a highly VAM dependant plant species.

The leaves are unpaired, pinnate, 20-30 cm long and the medium to dark green leaflets, which number up to 31, are approximately 3-8 cm long. The terminal leaf is often missing. The petioles are short. The shape of mature leaflets is more or less asymmetric.

Natural hybrids between A. indica and A. Siamensis , found in Thailand on places where both species grow together, have an intermediate position regarding the shape and consistency of the leaflets.

The white, gragrant flowers are arranged in axillary, normally more or less drooping panicles which are up to 25 cm long.

The glabrous fruits are olive- like drupes which vary in shape from elongate ovea to nearly roundish and when ripe are 1.4-2.8 x 1.0-1.5 cm . They are green when young and yellowish-green to yellow, rarely reddish when mature. The fruit skin (exocarp) is thin and the bitter-sweet pulp (mesocarp) is yellowish-white and very fibrous. The mesocarp is 0.3-0.5 cm thick. The white hard ‘shell (endocarp) of the seed encloses one, rarely two and very rarely three elongated seed kernels having brown testa.

Geographic Distribution

The neem is native of Indian subcontinent, it is widely distributed by introduction, mainly in the drier (arid) tropical and subtropical zones of Asia, Africa, the Americas, Australia and the South Pacific islands. In India it is widely distributed in many states. In Myanmar it is very common in the central parts of the country.

In the South Pacific neem occurs in the Fiji Islands. In Australia it was first introduced about 60-70 years ago. In Indonesia, neem exists mainly in the low-lying northern and eastern parts of Java and in the frier islands to the east (Bali, Lombok, Sumbawa). In the Philippines it was introduced during the seventies and eighties of the last century. In China, A. indica was planted on subtropical island of Hainan and southern china. In Nepal neem trees are found in the southern, low-lying areas (Tarai region). In Sri Lanka it is widespread in the drier northern parts of the island.

In Iran, neem trees grow along the coast up t the Chat el Arab in Iraq on the Arabian peninsula. In Qatar and Abu Dhabi neem was planted under irrigation using desalted seawater along avenues and parks. A large plantation was established on the Arafat plains near Makkah to provide shade for pilgrims.

Dear Jinan, thanks for your answer, that is good to know! Which species are those? Just in general whatever is attacking ornamental plants? Are there some dominant species? Greetings, Lukas

Good idea. However, you have to make sure that the biocontrol agent that you plan to manipulate will not create new problems. A first step is to make a thorough literature search to determine what is known about the host range of the biocontrol agent. A second step is to make preliminary work in enclosed environments such as greehouses so as this minimize the risks.

Ants as biological control agents in agricultural cropping systems

It is a tritrophic interaction study. One could do host plant rearing (i.e. fruits) to obtain pupa that can be raised to adults. Any pupa/larva that is parasitized could also be identified and possibly raised on a formulated diet. I guess there are also other methods available.

Dear, Simone,

Good evening Sir.

Your project is very interesting, but I don't know exactly if the fungus Hymenoscyphus fraxineus, the causal agent of ash dieback in Europe contains any virus in order to use this virus as a bioagent factor against this pathogenic fugus.

I hope you achieve that.

Each of six is important and number 2 may need to be addressed more.

You need to be more specific on what kind of biological control you are referring to; BC for insects, bacteria, fungi...? on humans, plants.... any specific BC category of your preference? Personally, I work on BC of insect pests of crops using nematodes.

Looks like Marietta leopardina ( Aphelinidae), an hyperparasitoid of Eulophid wasps. It is not an Encyrtidae

J. C. Tarafdar

Generally, review papers and book chapters are different in style. In both cases you must comply with scope and style of the target journal/book. The description of your document is vague. Which aspect of biological control are you addressing ? Which species or concepts are involved ? Is this new and original material ?

I also think this may help https://www.thespruce.com/eradication-of-japanese-knotweed-plants-2131201

Thank you Dr Saida Messgo Moumene

Please see this article about Trichogramma dendrolimi where they mention where to get them.

the days that have replaced the chemical drugs on the ocordonances (of our human health) by natural solutions and healthy diets will come that day.

@ Dr. Shibabrata Pattanayak

Beneficial Attributes of Parthenium hysterophorus

Despite of its detrimental effects on biological diversity, crop yield and human and livestock health, the Parthenium hysterophorus possess several beneficial properties. The plant is medicinally important and may also be helpful in increasing the crop yield. This weed can also be used as raw material for biogas plants.

Since Parthenium hysterophorous possess medicinal properties, hence it can be used as remedy for several diseases. The word ‘Parthenium’ has been derived from a Latin word ‘parthenice’ which also corroborates its medicinal significance. Traditionally local inhabitants of Central America frequently use Parthenium hysterophorus as ethnomedicine. 

The entire plant of Parthenium hysterophorus has bitter taste and is stimulant and antihysteric. The plant is equally important for both homoeopathic and allopathic systems of medicine. In homoeopathic system of disease treatment the whole plant is collected in the flowering stage and subsequently used for drug preparation. An infusion of Parthenium hysterophorus is effective against consumptive cases and in infirmities of mother. It is used as febrifuge, emmenagogue and tonic in allopathic system of disease treatment. The decoction of root is useful in dysentery, amoebic dysentery and in hepatic amoebiasis. 

The ‘parthenin’ (a major sesquiterpene lactone) extracted from the whole plant of Parthenium hysterophorus is pharmacologically active against rheumatism and neuralgia and is externally applied in skin diseases. The juice of the leaves is effective against earache.

Parthenium hysterophorus is well known for its allelopathic properties and it has been well established that allelopathy could be used to increase crop yield, to minimize crop yield expenses and to get rid of from the use of agro-chemicals that pollutes the environment.

Seed germination is problem related to crop production. Studies have revealed that extracts and leachates of Parthenium hysterophorus leaves help in the seed germination of linseed (Linum usitatissimum). Several other aspects like seedling vigour, growth and pest management of many agricultural crops like rice (Oryza sativa), wheat (Triticum aestivum), peanut (Arachis hypogaea) and maize (Zea mays) by using extracts of Parthenium hysterophorus is in experimental stage.

The dried leaves of Parthenium hysterophorus are effective against storage grain pests. The decoction of the leaves is used as flea-repellant. Leaves of Parthenium hysterophorus yield some essential oils.

Parthenium hysterophorus can be utilized as a raw material for biogas plants, as effective binding agent to check soil erosion and as component of vermi-compost. It may also be used as a green manure to ameliorate the physico-chemical properties of the soil.

Kindly go through the following PDF attachments.

Read this article bellow.

I agree with you Mohammad Abdulhai.

You could start a breeding programme using non affected coconut palms, or you could experiment with bio- insecticides targeting the pupation, like bacillus thuringiensis. I just read that there are also attempts to clone proteins that target insect juvenile hormones.

https://www.sciencedaily.com/releases/2000/12/001211193526.htm

Interesting, you can be sure respected Arvind Singh will supply that.

Dear Doctor K. According to Hawaii researchers anthracnose and powdery mildew are the worst fungal diseases of mango.

For disease control the use of dwarfing rootstocks would allow the management for these diseases which would probably require the penetration and coverage of the foliar and fruit. The tinne motorized spray equipment would be needed plus a program of pruning and canopy thinning on going.

The locating of mango in consistently arid conditions can be effective for anthracnose plus resistance varities. Powdery mildew does not have a high water spread requirement.

You may want to work on powdery mildew for your mycovirus approach.

Best Luck, Paul Reed Hepperly

thanks for sharing the information !

Best,

Joe

Hello see attached info may be useful for you.

Good luck!

Dear Drlatief Ahmad

have a look at these links. hope be useful.

I think article would be so helpful:

"Biocontrol of Bacillus subtilis against Infection of Arabidopsis Roots by Pseudomonas syringae Is Facilitated by Biofilm Formation and Surfactin Production"

Regards

You've tried adding a drop of Tween-20? That works for hydrophobic spores, although it can be fungitoxic. There was a time when we sprayed spores in liquid Freon, but that might be illegal now. Depending on your spray rig, you might be able to use a 0.01-0.02 % water-agar solution, which holds spores more uniformly in suspension.

Predators play a key role in regulating pest populations (Jazzar and Hammad, 2004), and show a great potential in controlling pests than parasitoids and pathogens. You can try many predators. The most common predators include ladybird beetles (Coleoptera: Coccinellidae), true bugs (Hemiptera: Anthocoridae and Miridae), lacewings (Neuroptera: Chrysopidae), and mites (Acari: Phytoseiidae). However, biological control by predators represents a key strategy whose potential has gone largely unrealized in many affected cropping systems throughout the world.

You might benefit from this University of Wisconsin Extension publication with a very practical explanation and some references. The summary is this bacteria has demonstrated growth promoting activity which favors health. Secondly the bacteria is very effective in colonizing and competing with pathogenic bacterial and other microbes in the root rhizosphere region. Thirdly beside the production of growth factors, competition it does produce several antibiotics which are lethal agents to pathogens and finally there is much information now developing that the bacteria can trigger the systemic acquired resistance mechanism. One of growth promoting mechanisms associated with the bacteria is the capacity to solubilize Phosphorus this is very important is the potato crop which has a high Phosphorus requirement and is grown under low temperature regimes which dampen the natural soil solubilization of Phosphorus. Hope you find some good information.

Good afternoon.

Thank you very much for your share.

I think this article will be very useful for my work.

Best regards.

I suggest the journal 'Phytoprotection' from the Quebec Society for Protection of Plants

usou nca ytsenFogr fungal biocontrol a

Sugar crop research institue, Mardan, Khyber Pakhtunkhwa, Pakistan

Address:

Charsadda Road, 23210, Mardan

Khyber Pakhtunkhwa, Pakistan

Ph: +92 937 929013,

Email: 1) mtahir_director [ at ] yahoo.com.

2) tasran [ at ] gmail.com

best regards

Dr. Muhammad Ashraf Khan

Hi.. prof. Jawad K. Abood Al-Janabi

this link the articles maybe help you.

Good luck

Hi Amer

It is possible to rear Nesidiocoris on tobacco plants within insect proof cages (T:25 degrees Celsius/ RH:70%) and feed your colony with Ephestia eggs. You would have to vacuum next generation larvae about 3 weeks later and infest newly setup cages. This is not the most effective method to produce heaps but it could help as a start. Cheers, Bruno

The development of any pest management strategy does not rule out any of the different control elements. The integration of all elements with follow-up of the pest, according to the processes of prediction, investigation, control, exclusion and intervention using pesticides is necessary in the event of a pandemic.Because most biological and other control factors still do not result in rapid response

You could refer to

Ash, G. (2010). The science, art and business of successful bioherbicides. Biological Control, 52(3), 230-240.

The taxonomy of Chrysopidae is particularly difficult and it is often impossible to distinguish species morphologically. In that case, accoustic mating signals are used to identify them to species level. Obviously, this would require you sending live specimen (males) to expert taxonomists.

You can try contacting

Dr Peter Duelli, Zoological Institute, University of Basel, Rheinsprung 9, CH-4051 Basel

or

Charles S. Henry, Dept of Ecology & Evolutionary Biology, University of Connecticut

Dear Mina,

We investigated on some plant extracts to control boxwood moth. fortunately they were effective. now we are trying to use it in forests by help of Forests, Range and Watershed Management Organization in Iran, if they cooperate.

Hi Rex,

First of all, because we understand that you managed to control your system, I guess that, by closing your loop with a proportional gain P, you already got a stable (maybe not too good, yet not unstable) system.

Then, playing with the D and I gains gave you better performance, although not necessarily as good as you may want.

Identification is a good idea, yet this requires knowing the number of parameters that you must identify, or, in other words, the exact order of your system, which I doubt is available if you talk about a totally unknown system.

However, now you can take a Signal Analyzer and find the frequency response of your stable closed-loop plant. This would give you the graphs of Amplitude and Phase and a first idea about the transfer function (TF) of your system.

From here, there are procedures (for example in MATLAB) that allow you to compute the open-loop TF, etc.

I hope it helps.

Have Fun!

Itzhak

Thanks, Archie, I missed those. 

Yes, my email: cmv_virus2002@yahoo.com

20

I think of it this way.

Biocide: This product kills everything. Sodium hypochlorite (bleach) is a biocide. It kills bacteria, insects, people, plants, and everything else that cannot escape.

Pesticide: these products are generally not biocides. They are at least somewhat selective. You can have subclasses like rodenticide, herbicide, insecticide, fungicide, and so forth. Pesticides can be synthetic, derivatives of natural products, or natural products.

Biopesticide: like pesticide but restricted to unmodified natural products. I can envision a time when some company will genetically engineer Bacillus thuringiensis. I am not sure if the resulting bt product would be a biopesticide or a pesticide.

No, Phytoseiulus  persimilis do not prey on Bemisia tabaci eggs. You should try Chrysoperla carnea (Neuroptera; Chrysopidae), Delphastus pusillus , Harmonia axyridis and Azya orbigera (Coleoptera: Coccinelidae). They will feed  on whitefly eggs, nymphs, and adults of Bemisia tabaci. Also the bug Macrolophus caliginosus (Hemiptera: Miridae) is polyphagous and feeds on eggs, pupae and adults of B. tabaci.

Integrated pest management strategy will work.

Dear All,

Also some endosymbiotic bacteria can cause colour change in aphids

The two most commonly used methods to eliminate viruses in grapevine are thermotherapy (35°C for 3 months) and apex micrografting.

These links might be useful :

The French Institute for Vine and Wine (IFV) offers a virus clearing service through micrografting and I invite you to get in touch with the person in charge of the laboratory (anne-sophie.spilmont@vignevin.com) if you wish to obtain further information.

Good luck !

By the way, from this web link (http://livewell.jillianmichaels.com/canola-oil-compared-olive-oil-5365.html), it indicates "Canola oil must meet specific regulations regarding erucic acid a glucosinolate content, with no more than 2 percent erucic acid and 30 micromoles per gram of glucosinolates." So, I guess today's canola oil probably is not erucic acid zero, but only low in amount. But, as Rahul Kumar has mentioned, with known biosynthesis pathway, and genes controlling this pathway, one can use CRISPR to knock out these genes and get erucis acid-free (zero) plants.

l

 The UF researchers have identified citrus cultivars, in this case 16 citrus rootstocks, most of which show a lower rate of infection and more tolerance to citrus greening.

By Robert H. Wells, University of Florida | Sep 27, 2013(http://news.ifas.ufl.edu/.)

Results suggest classifying Carrizo, US-897, and US-942 as tolerant, US-802, US-812, and Volkamer lemon as moderately tolerant, and Cleopatra mandarin as susceptible to Las. Despite irregular growth, low rates of infection and low Las numbers indicate some resistance of Benecke to Las. Additional greenhouse experiments and field observations confirmed findings for US-802, US-897, US-942, and Cleopatra, although results for US-802 were more variable.PDF enclosed..

Look like larva of Anarsia lineatella, commonly known as Peach Twig Borer.

Management data link--

green leaves are used as organic amendment which have shown nematicidal activity. Dry leaf powder is also rich in polyphenols, flavonols and glucosides are active secondary metabolite, these are present in dry powder also, so you can try..

13

I think the most susceptible insects are the nymphs of Bemisia sp. or Trialeurodes vaporariorum and aphids.

Hi,

I think that you have specimens belong to Telenomus (Scelionidae, Platygastroidea), possibly T. polymorphus Costa Lima, 1943, but I  am not sure because is difficult to identify the species level using only the pictures.

Best regards,  Ovidiu 

Baba Plant Care - Natural Camelia Seed Powder

If anyone possesses this book, please kindly share with us thanks a lot in advance. 

Thank you, Sir Laith Al-Ani. I haven't gone through or even saw some of the references you listed so it would really be a big help for my research :)

This is not your question but I would by far favor Baculoviruses ;-)

You most welcome

Houda