scientist studies on gmo and roundup - Page 5
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  1. #81
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    Default Re: scientist studies on gmo and roundup

    Quote Originally Posted by Oldtimer View Post
    Yet 17 years later, all these products are working fine. Every now and then somebody claims they treated and it failed, but seems there may have been other factors at play because in following seasons there has not been resistance.
    I don't really know OT, but my friends in Otorohanga and Wellington are both facing Bayvarol resistance...according to them. One lost half his bees and the other couple lost lots and their colonies were above the mite threshold to be able to send packages to Canada (1%). 200-500 colony operations. You met the couple when they dropped Lesley and I at the War Museum. Are they wrong? Is it something else?

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  3. #82
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    Default Re: scientist studies on gmo and roundup

    Yes I know of it, and others have claimed bayvarol resistance.

    But even quite a few years ago some commercial beekeepers were finding apistan or bayvarol resistance, yet a few years later they'll be back using it again, the resistance seems to have gone.

    My own hives were treated with bayvarol last fall, and now during the spring round I have found maybe a 1/2 dozen hives with mite damage and had to re treat them with apivar before the normal time. But I'm rotating a number of treatment types and I'll bet next time they get treated with bayvarol it will work.
    "Every viewpoint, is a view from a point." - Solomon Parker

  4. #83
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    Default Re: scientist studies on gmo and roundup

    Resistance has a metabolic price that typically makes the resistant organism somewhat less fit than wild type. So, when resistance happens a few generations without exposure and it is not uncommon to find the organism to once again be susceptible. When you rotate toxins that differ in the critical metabolic paths resistance to one does not in any way make it easier to become resistant to the second or third. And better yet, those individuals resistant to one are likely to be among the first killed by the second or third erasing resistance even faster than non exposure would erase it. The exception to these general rules would be when resistance is the result of horizontal gene transfer. In such cases resistance tends to be persistent. But, a great many cases of resistance are just due to up regulation of some metabolic pathway that stops toxicity and changing the regulatory genetics is generally very easy compared to changing a coding gene.

  5. #84
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    Default Re: scientist studies on gmo and roundup

    A question Richard, because a lot of mite reproduction is incestuous, do you see this as a problem in terms of them losing resistance to a control chemical? IE, let's say an animal of some kind was resistant to something, but reproduced sexually, you might expect the resistant genetics to be diluted. But a lot of mite sexual reproduction is within the family, so could retain a particular gene more?
    "Every viewpoint, is a view from a point." - Solomon Parker

  6. #85
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    Default Re: scientist studies on gmo and roundup

    Good question. I do not think anyone really knows the answer to your question. For sure I do not. Their mode of reproduction forces a lot of brother sister matings so I would expect mites to carry very few recessives that are deleterious. But, they also sure try for outcrosses when the mite population builds and from what I have read they do this on purpose, not just as a mater of statistics due to lack of enough drone cells. So, they make some positive attempt to get non incestuous matings as I understand the situation. Resistance may go away a bit slower than in a species that relied mainly on total out crosses but should still go away given enough time. One of these days someone is going to make some GMO mites involving a gene drive that makes use of this stuff and results in less viable mites I suspect. It will likely be turned loose illegally as no one is going to pay all the money to get them approved when no one can make a buck off the GMO product. You do not need to knock down their reproductive capacity very much to make a huge difference in how much of a problem they are to us bee keepers. To optimize the value of such a GMO you do not want something totally lethal or it would not spontaneously spread in the mite population. You want something that cuts reproduction by 50% or maybe even less. If you look at Randy Oliver's mite population models it is clear a pretty small change in reproduction rate makes a real big difference in mite population in a few months. One approach would be to put some genetics in them that makes them weakened by some virus such as DWV and use the disease to our benefit.

  7. #86

    Default Re: scientist studies on gmo and roundup

    Quote Originally Posted by Richard Cryberg View Post
    But, they also sure try for outcrosses when the mite population builds and from what I have read they do this on purpose, not just as a mater of statistics due to lack of enough drone cells. So, they make some positive attempt to get non incestuous matings as I understand the situation.
    How? Can you elaborate on this a little more?

  8. #87
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    Default Re: scientist studies on gmo and roundup

    More than one mother mite goes into the same drone cell, so the offspring can interbreed.
    "Every viewpoint, is a view from a point." - Solomon Parker

  9. #88

    Default Re: scientist studies on gmo and roundup

    Understood.
    Thanks, OT.

  10. #89
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    Oct 2012
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    Vancouver, B.C., Canada
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    Default Re: scientist studies on gmo and roundup

    Here are 2 scientific studies that show a possible long term negative impact of Roundup on honey bee colonies. The first study shows the effect on appetite https://drive.google.com/file/d/0Bx7...ew?usp=sharing
    "we speculate that successful forager bees could become a source of constant inflow of nectar with GLY traces that could then be distributed among nest mates, stored in the hive and have long-term negative consequences on colony performance." The second study shows the effect on navigation https://drive.google.com/file/d/0Bx7...ew?usp=sharing
    "*in honey bees, exposure to levels of GLY commonly found in agricultural settings impairs the cognitive capacities needed to retrieve and integrate spatial information for a successful return to the hive. Therefore, honey bee navigation is affected by ingesting traces of the most widely used herbicide worldwide, with potential long-term negative consequences for colony foraging success."

  11. #90
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    Dec 2011
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    Lottsburg, Virginia USA
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    Default Re: scientist studies on gmo and roundup

    Glyphosate reduction in appetite would not appear to effect humans as can be judged by the increase in obesity in the Western world.
    Johno

  12. #91
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    Oct 2012
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    Vancouver, B.C., Canada
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    Default Re: scientist studies on gmo and roundup

    Quote Originally Posted by johno View Post
    Glyphosate reduction in appetite would not appear to effect humans as can be judged by the increase in obesity in the Western world.
    Johno
    Very true. Maybe it has a reverse effect on humans.

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