CREI initiates Research to find Biological Control to combat Citrus Greening

Biological Control is a systematic method of killing parasites, bacteria and predators using other living organisms. It is an environmentally sound and quite effective means of protecting plants and it has extended to countries all over the globe. Instead of the traditional use of chemically-induced sprays, environmentalists are now looking for diseases that naturally kill incest’s, then dispensing it into plant fields with the objective of destroying pests and plant vlcsnap-2013-02-19-18h44m26s48diseases. The Citrus Research and Education Laboratory (CREI), a branch of the Citrus Growers Association is in the initial stages of introducing this method to Belize’s citrus industry. Their objective is to reduce the Huanglongbing Virus, formerly known as citrus greening. Plus TV travelled down south and took a tour of the CREI lab to learn more about this latest experiment. He met up with Dr. Drayon Bucias who was in Belize facilitating the experiment. As we learnt, the first stages of bio control is collecting insects that have died from natural diseases and then extracting the fungi from those diseases. Dr. Bucias explains.

Dr. Drayon Bucias:
vlcsnap-2013-02-19-18h46m54s237We’re isolating the pathogens that are associated with this around the surface, and we have to use the little micro-needle to pull it off, and we put it on media. The first stage is the get them on the scope.  We add a little moisture, and then we capture the spores on artificial media, which are next door.
We also do microbiolasics, where we put a cutting of Orange Jasmine, we innoculate the insect, and then we inoculate the fungus. So we do our reading on micro-scale first.  This gives us the ability to assess, first of all variants, and it also gives us the ability to assess overall performance. Then we scale it up.

The purpose of extracting numerous fungi is to test which will be most suitable to carry out bio control.

Dr. Drayon Bucias:
vlcsnap-2013-02-19-18h49m19s198The point of this research is to find the strain that’s best, the strain that not only infects that first generation, but also persists and spreads. It’s one thing to have a microbial pesticide that you spray on the killer bunch, but it’s more ideal in this scenario to put something out that inoculates it, even if it only kills 60/70 percent, as long as it persists and spreads and gives that continuous benefit. That’s much more beneficial

What makes this process important is that the lab will not be importing a new species or organism into Belize to fight the citrus greening. Rather, CREI intends to use fungi that are native to Belize.

Dr. Drayon Bucias:
We took those insects and we made isolates.  We’ve got about 40 isolated growing on petri dishes.  There’s a variety of different feeder types that we have. We don’t know what some of it is. This is not sporelated yet. {These are] all Belizean strains. I’ve got a large collection back in Florida, but the idea is that if we use Belizean strains, the regulatory problems may not come up, of importing a foreign microbe.  We’re using a natural agent, amplifying it up, and releasing it.  This is one of the things that Veronica and the group here really insisted on.  We target that.

This process will occur several times until the best strains of biological control are ready for field testing.

Dr. Drayon Bucias:
We’ve got a couple of small batches.  This is one, for example, that we’ve started testing today.  This is another fungus, but it shows very well.  You can vlcsnap-2013-02-19-18h51m40s43see the difference in spoliation, the green colouring.  You can smell it.  It smells like a mushroom.  The green colour versus the whitish colour, and there are  different species. So the idea is to grow it up at this level, and this is a very small amount, it’s only about 200 grams of rice.  When we harvest this, and we did harvest some of this, get it to this point, and then test it again.  It’s really simple, you take mild soapy water and you add it to the bag of rice, you shake it up, and then you filter it through cheese-cloth.. Then you end up with a spore preparation, and we have a way of calibrating how many spores are in this.  This is what we would spray out on the field.

According to Dr. Bucias, the process can take as long as six to nine months. The final approved biological control will then be available to all citrus farmers to use in the control of citrus greening. It will then be distributed into plant fields.

Dr. Drayon Bucias:
It would be at least six to nine months before we’re through with that. if everything goes smoothly. I can say if we’re getting high valance or something like this, with some of the easy growing ones. it can be shortened. But if it’s some of the more fastidious growing strain, the ones that require longer time, more nutrients, more finicky, it could require up to two years.
There are several ways you can [disseminate it in the field]. You can use biological control, where you inoculate it, to a point source inoculation into a population, and then it will spread naturally.  That’s ideal.  It will allow it to spread and persist.  That’s the ideal situation.  There’s also another mechanism where we can actually harvest this and spray it out, broadcast it as a microbial insecticide.

Dr. Bucias will return to Belize to continue the research, where Belizeans can look forward to more advancement in bio control. The research is funded by fees that farmers make to the Citrus Growers Association.

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