Volume 2, Number 11, November, 1984

Copyright ©1984 M.T. Sanford "All Rights Reserved"

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In this issue:

Canker and Moving into Citrus Groves
CANKER AND MOVING INTO CITRUS GROVES
Since citrus canker has been found, there was considerable concern at the Florida State Beekeepers Association Convention in Jacksonville about moving bees into citrus groves this spring. At the present time, the citrus industry has no standard policy on the situation. However, grove owners and others are aware of the problem, and there is expected to be movement on this front. It was emphasized at the meeting by Agriculture Commissioner Conner that beekeepers should communicate with grove owners and managers before entering groves. Although there is a possibility that the honey bee may spread the canker bacterium, it is not very probable. Of much more concern are people and equipment in groves.

It beehooves the beekeeper, therefore, to become familiar with suggestions and regulations about moving into and out of citrus groves. If the beekeeper will approach the grover owner or manager in a diplomatic way and provide evidence that he/she is aware of potential problems and informed about them, the chances of being allowed into groves are considerably increased. The following are sanitation procedures to reduce risk of spreading canker:

Before entering groves, all equipment and vehicles should be free of plant litter, soil, and should be cleaned (and scrubbed) with a solution of quaternary ammonia that contains a detergent. Most owners/managers will be familiar with specific materials to use. Below are the latest recommendations (10/18/84), as published by the Cooperative Extension Service:

Disinfestants can contain quaternary ammonium compounds present in single, dual or multi-compound formulations. A disinfestant could contain (l) a single quaternary ammonium formulation like n-alkyl-dimethyl-ethylbenzyl ammonium chloride, (2) a dual quaternary ammonium formulation like n-alkyl dimethyl benzyl ammonium chloride and n-alkyl dimethyl ethylbenzyl ammonium chloride, (3) a multi-quaternary ammonium formulation can contain a number of such compounds.

In the original Citrus Canker Action Plan, materials containing a single quaternary ammonium compound formulation were recommended. The most recent Division of Plant Industry recommendation for materials containing quaternary ammonium compounds include one dual compound formulation and one multi-compound formulation:

     l)  Dual quaternary ammonium formulation
            This material contains the following 2 compounds.

            a) n-alkyl dimethyl benzyl ammonium chloride
            b) n-alkyl dimethyl ethylbenzyl ammonium chloride

     2)  Multi-quaternary ammonium formulation
            This material contains the following 4 compounds.

            a) Octyl decyl dimethyl ammonium chloride
            b) Dioctyl dimethyl ammonium chloride
            c) Didecyl dimethyl ammonium chloride
            d) n-alkyl dimethyl benzyl ammonium chloride
All disinfestants recommended should contain either the above mentioned dual quaternary ammonium compound or the multi- quaternary ammonium compound. These are not standard household ammonium solutions; they are not sold in groceries or pharmacies and must be purchased at grove chemical supply houses. Before buying any compound, it is imperative beekeepers first check with grove owners.

All disinfestants recommended should be used at 2000 parts per million (0.2%) TOTAL QUATERNARY COMPOUNDS and should contain a compatible detergent. Detergents must be non-ionic in order to maintain the biological activity of these compounds. Non-ionic detergents will be described as "detergent disinfectants" or "cleaner disinfectants" and not simply as "sanitizers" or "disinfectants."

Before entering and leaving groves, hands should be cleaned with soap and water, or hands may be disinfested with rubbing alcohol (70% isopropyl). Rubbing alcohol has been shown to effectively kill the canker bacterium on contact.

WARNING: Rubbing alcohol is flammable and is highly poisonous if consumed internally.

All personnel should wear freshly cleaned attire each day.

As a footnote, it should be realized that it is now against the law to move into citrus groves, unless in compliance with Emergency Rule 5BER84-10, promulgated by the Division of Plant Industry. Paragraph 5 states:
"Entry of persons, equipment or other articles into citrus plantings is prohibited unless such persons, their clothing, the equipment, and the other articles have been disinfested or decontaminated, utilizing a method prescribed by the USDA or the Department."
[Editor's note: This is placed here as an historical record; canker, however, could be found at any time in the future]

THE HONEY BEE TRACHEAL MITE
Most recent information (November 13) indicates the honey bee tracheal mite has been found in twenty-seven locations in ten counties: Lake , Glades, Palm Beach, St. Lucie, Putnam, Polk, Highlands, Hillsborough, Broward and Dade. Depopulation of colonies has not been instituted in Florida, but colonies, beeswax and beekeeping equipment in these sites have been quarantined.

At a recent meeting at the Division of Plant Industry in Gainesville, a Mite Advisory Committee was appointed, as directed by Agriculture Commissioner Conner. Felix Uzell, Sebring was selected as chairman; the membership includes Horace Bell, Deland; Marvin Brown, Tampa; Harold Curtis, LaBelle; Bill Merritt, Tallahassee; Frank Robinson, Gainesville; Lawrence Cutts, Chipley, Harold Denmark, DPI Gainesville, L.L. Lanier, Wewahitchka and B.J. Lewis, APHIS, Jacksonville. The Committee will be advising the Commissioner about the impact of the mite on Florida beekeepers. The most recent meeting of the Committee was held in Gainesville, November 16. At that time the Committee decided to recommend to Commissioner Conner that status quo of quarantining colonies continue until December 31, at which time the situation will be reassessed. Those interested in the future of the beekeeping industry should maintain contact with appropriate members of the Committee so that your ideas can be voiced.

Meanwhile sampling of bees continues. At the present time some thirty two persons are involved in sampling bees from all over the state to determine if the mite is widespread. If so, the entire state may be quarantined, which would allow beekeepers to move bees within the state, but not beyond its borders. As the situation stands now, only bees in officially quarantined areas are prohibited to move. The Division of Plant Industry has girded itself to take on the enormous task of trying to survey the state. It has even called retired Chief Apiarist, Jim Herndon out of retirement. Jim is now the coordinator of the Honey Bee Tracheal Mite Project and will be working with regulatory officials, the Advisory Committee and others involved in sampling and examining perhaps as many as five million individual bees in the next few months.

The terms "Acarine Mite" and "Acarine Disease" are no longer appropriate to use in conjunction with Acarapis woodi. Instead, the parasite should be called the honey bee tracheal mite. There are still many questions and few answers about the mite's biology and behavior. Dr. H.L. Cromroy, IFAS acarologist, recently published a short piece in the American Beekeeping Federation Newsletter, "Bee Mites--What is and What is Not!" (September/October 1984). According to Dr. Cromroy, missing information on the honey bee tracheal mite includes:

a. How does the mite find young bees to infest?
b. How rapid is the rate of infestation?
c. What percentage of a colony has to be infested before honey production is decreased?

Based on what has been published about the honey bee tracheal mite, the following life cycle is provided. The full cycle takes from 19 to 21 days, and individuals go through egg, larva, quiescent nymph and adult stages.

Dr. Cromroy also suggests that several things should be empasized about the mites that are extremely important to beekeepers and the beekeeping industry:

a. Mites infect only adult honey bees--there are no other known insect hosts.
b. Mites DO NOT PRESENT A DANGER TO HUMANS
c. Honey from mite-infested colonies in not affected in any manner and is SAFE FOR HUMAN CONSUMPTION.

[Editor's note--This is historical in nature, but still contains good information; the mite has now been introduced in most parts of the U.S. and some of Canada]

Sincerely,

Malcolm T. Sanford
Bldg 970, Box 110620
University of Florida
Gainesville, FL 32611-0620
Phone (352) 392-1801, Ext. 143 FAX: (352)-392-0190
http://www.ifas.ufl.edu/~entweb/apis/apis.htm
INTERNET Address: MTS@GNV.IFAS.UFL.EDU
©1984 M.T. Sanford "All Rights Reserved

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