Tropical Fruit Forum - International Tropical Fruit Growers

Citrus => Citrus General Discussion => Topic started by: Millet on August 01, 2017, 05:51:05 PM

Title: Asian Citrus Psyllid Survival
Post by: Millet on August 01, 2017, 05:51:05 PM
The two major factors that have a significant impact on the development of psyllid population, and their survival, are the availability of new growth flushes for the female ACP to lay their eggs and the temperature.  In laboratory studies it was observed that approximately 50 percent of the ACP population can tolerate low temperatures at or below freezing (32-F) for two days,  These temperatures are below most citrus growing areas. ACP subjected to higher temperatures of 104-F to 114-F the survival rate decreased by 95 percent to 100 percent.  Therefor, it would appear that as temperatures increase or decrease from the optimal life temperature range of 68-F to 77-F, the rate of ACP mortality is affected.  The impact of higher temperatures have greater effect on the death rate than exposure to lower temperatures.
Title: Re: Asian Citrus Psyllid Survival
Post by: mrtexas on August 01, 2017, 06:29:45 PM
The two major factors that have a significant impact on the development of psyllid population, and their survival, are the availability of new growth flushes for the female ACP to lay their eggs and the temperature.  In laboratory studies it was observed that approximately 50 percent of the ACP population can tolerate low temperatures at or below freezing (32-F) for two days,  These temperatures are below most citrus growing areas. ACP subjected to higher temperatures of 104-F to 114-F the survival rate decreased by 95 percent to 100 percent.  Therefor, it would appear that as temperatures increase or decrease from the optimal life temperature range of 68-F to 77-F, the rate of ACP mortality is affected.  The impact of higher temperatures have greater effect on the death rate than exposure to lower temperatures.

I had psyllids one spring in SE Texas 5 or so years ago and the next winter we had a good hard freeze and they disappeared and didn't come back. Maybe the high temperatures where they grow citrus in California will be of some help. They appeared on my trees here in Sugar Land,TX this spring so I sprayed them the next 3 days and they also disappeared. We had a 19F freeze this winter two nights in a row so I hope it got them good in the rest of the area. So far no greening. Many of the trees I have in pots were propagated with budwood from 5 years ago. The 15 trees in the ground came from a psyllid free nursery or with certified bud wood.
Title: Re: Asian Citrus Psyllid Survival
Post by: AndrewAZ on August 02, 2017, 12:36:57 AM
Well, maybe the days in a row in Phoenix may actually be good for something!
Title: Re: Asian Citrus Psyllid Survival
Post by: usmcgy01 on August 16, 2017, 03:32:55 PM
My friend Sharon has a banana tree and a papaya tree.  Neither tree has had fruit for 10 years.  She bought some OMG Fertilizer and within 3 weeks, both trees blossomed.
She said she bought it from www.omgfertilizers.com (http://www.omgfertilizers.com). 
Title: Re: Asian Citrus Psyllid Survival
Post by: fyliu on August 16, 2017, 04:41:24 PM
My friend Sharon has a banana tree and a papaya tree.  Neither tree has had fruit for 10 years.  She bought some OMG Fertilizer and within 3 weeks, both trees blossomed.
She said she bought it from [url=http://www.omgfertilizers.com]www.omgfertilizers.com[/url] ([url]http://www.omgfertilizers.com[/url]).

Welcome to the forum!

I think you posted in the wrong thread. Make a new thread if you want to post a product testimonial or recommend a product with some personal experience.

This thread has very low views so not many people are seeing what you want them to.
Title: Re: Asian Citrus Psyllid Survival
Post by: countryboy1981 on August 16, 2017, 04:45:23 PM
Hopefully they will find a solution.  I think the least controversial if they can't cure the disease itself in infected trees would be to either breed specifically for or genetically modify the acp to not transmit the disease and release those insects to breed.
Title: Re: Asian Citrus Psyllid Survival
Post by: fyliu on August 16, 2017, 05:05:45 PM
Hopefully they will find a solution.  I think the least controversial if they can't cure the disease itself in infected trees would be to either breed specifically for or genetically modify the acp to not transmit the disease and release those insects to breed.
Good suggestion but this one's already been considered.

They considered releasing modified ACP similar to what they do with mosquitoes. I forgot why but they said it's not going to work. The bugs don't care about pheromone or something.

Researchers do consider and try all the options they have, even the ones that have potential dangers like parasitoid wasps. They studied them and did tests to make sure the wasps won't turn out to be a pest themselves. They should really post a list of the stuff they already tried so we can see if we have something new they should try out.
Title: Re: Asian Citrus Psyllid Survival
Post by: brian on August 23, 2017, 08:29:28 AM
Would this be away to sanitize new trees after receiving them?  Subject to 115F heat for some time?
Title: Re: Asian Citrus Psyllid Survival
Post by: Susanne42 on August 23, 2017, 12:11:22 PM
If the psyllid prefers new flush to lay eggs, maybe it would help to delay fertilizing the trees? Or put a screen around during new flush to minimize attack?
What makes this pest feel comfy or uncomfortable?
Title: Re: Asian Citrus Psyllid Survival
Post by: Millet on August 23, 2017, 02:54:55 PM
The psyllid sucks both on the new and old leaves. 
Title: Re: Asian Citrus Psyllid Survival
Post by: Citradia on August 23, 2017, 08:48:36 PM
And, I think it only takes one infected psillid ( let's assume they're all infected) to infect and essentially doom your tree. The efforts to cover citrus to protect from psillids in warm climates makes me think about myself running around trying to cover and protect trees from cold in winter. Sounds like everybody is going to building some kind of framework around their citrus trees for one reason or another.
Title: Re: Asian Citrus Psyllid Survival
Post by: Susanne42 on August 23, 2017, 09:36:24 PM
Mayne find a cure for the sick psyllid??? I know, strange way to think.
Any natural predators in China?
Title: Re: Asian Citrus Psyllid Survival
Post by: Citradia on August 24, 2017, 08:12:29 AM
I read somewhere that in china they just replace trees as they die. No cure.
Title: Re: Asian Citrus Psyllid Survival
Post by: Citradia on August 24, 2017, 08:14:14 AM
Has there been anymore talk about the Florida plantain weed and other rue family members that are vectors for infection? Are they going extinct too?
Title: Re: Asian Citrus Psyllid Survival
Post by: fruitmentor on August 24, 2017, 02:52:11 PM
I think the comment about psyllids "disappearing" is a bit misleading. They are very hard to spot. I heard last week that one of the big citrus growers from Florida who never saw a single psyllid in the grove was losing trees to huanglongbing. They may be around even without being seen. In the absence of ants on a citrus tree the psyllids may be controlled to a low level by natural predators.
Title: Re: Asian Citrus Psyllid Survival
Post by: mrtexas on August 24, 2017, 07:21:22 PM
I think the comment about psyllids "disappearing" is a bit misleading. They are very hard to spot. I heard last week that one of the big citrus growers from Florida who never saw a single psyllid in the grove was losing trees to huanglongbing. They may be around even without being seen. In the absence of ants on a citrus tree the psyllids may be controlled to a low level by natural predators.

IMHO not true. The droppings of the nymphs look like little white squiggles. The psyllids are small but you can
see them if you are looking for them. They are small brown triangles the size of aphids.
Title: Re: Asian Citrus Psyllid Survival
Post by: mrtexas on August 24, 2017, 07:45:02 PM
The psyllid sucks both on the new and old leaves.

Not in my experience. They only attached the very newest growth even
before it was big enough for the leaf miners to get into.
Title: Re: Asian Citrus Psyllid Survival
Post by: Millet on August 24, 2017, 09:03:16 PM
Thanks Phil, every day one learns something new is a great day.