CITRUS

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0 height="100%"><tr> <td valign="top" width=200 BGCOLOR="#FFFFFF" TEXT="#080000"> <div> <IMG SRC="06f572e0.jpg" border=0 width="87" height="46" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"><IMG SRC="097b82f0.jpg" border=0 width="184" height="303" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </td> <td valign="top" BGCOLOR="#FFCC80" TEXT="#080000"> <div> <FONT SIZE="5" COLOR="#000000" FACE="Arial" ><B>HOME</B></FONT>     |     <A HREF="index.htm" TARGET="_top" TITLE="HOME"><U>home</U></A></div> <div> <A HREF="id24.htm" TARGET="_top" TITLE="GOT STRAWBERRIES?"><U>GOT STRAWBERRIES?</U></A>   |   <A HREF="id25.htm" TARGET="_top" TITLE="GOT APPLES?"><U>GOT APPLES?</U></A>   |   <A HREF="id26.htm" TARGET="_top" TITLE="PORK"><U>PORK</U></A>   |   <A HREF="id28.htm" TARGET="_top" TITLE="GOT CHICKEN?"><U>GOT CHICKEN?</U></A>   |   <B>CITRUS</B>   |   <A HREF="id48.htm" TARGET="_top" TITLE="DAIRY"><U>DAIRY</U></A></div> <div> CITRUS</div> <bR> <div> <B> AgSCAN </B>conducted a few experiments for a major citrus growers association to demonstrate the post harvest benefits of applying radiation to citrus fruit infected with the fungus- penicillium digitatum . Lemons and oranges were inoculated with the spore placed into a small cut made in the rind of the fruit. The inoculate was  concentrated at 1 million spores per cc.</div> <div> The fruit were radiated at two absorbed doses;  300 Gy and 500 Gy. At the higher absorbed dose it was shown that a better than log reduction had been made in all fruit. Subsequent taste testing and other subjective tests were upon radiated fruit with satisfactory results. It was reported by the taste testers that oranges were even sweeter after the radiation than was apparent in the control specimens. It was generally thought that the enzymes in the fruit were hyper-activated to react with carbohydrates to form sugars.</div> <div> These experiments clearly indicated to all that an end could be made to post harvest application of chemicals upon citrus fruit. The shelf life was extended  to nearly double the norm. All in all, the results appeared to hold a cost saving benefit to growers of citrus fruit, and to distributors and retailers through reduced spoilage. Extended shelf life is important to shipment of exports, and in general reduces losses at retail.</div> <bR> <bR> <div> <B>Citrus Fruit Factsheet </B></div> <div> <TABLE BORDER="0" CELLPADDING="1" CELLSPACING="1" WIDTH="192" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="VOID" RULES="NONE" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=CENTER HEIGHT= 19 WIDTH="188"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="19" ALIGN="bottom" WIDTH="188" HSPACE="0" VSPACE="0"></tD> </tR> </TABLE></div> <DIV ALIGN="LEFT"></DIV> <div> <B>Postharvest Citrus Diseases</B></div> <div> <B>GREEN MOLD</B></div> <div> Green mold is a postharvest disease caused by the fungus Penicillium digitatum that infects through injuries to all types of citrus fruits. Even injuries that involve only a few oil glands are sufficient to induce infection. The fungus survives in the field on soil debris and produces spores that infect split and injured fruit in the tree and on the ground. At cooler fall and winter temperatures that favor fungal development, large numbers of spores are produced and carried by wind currents to surfaces of fruit in the tree canopy. The spores germinate when nutrients and moisture are released at injuries that are formed during harvesting and handling. The fungus is a prolific spore producer, and airborne spores easily contaminate soak and drench tanks, degreening and storage rooms, the packing house and equipment, transit containers, and even the retail marketplace. Due to its ability to produce large masses of spores, the fungus has the potential to develop resistance to post harvest fungicides. </div> <div> <B>Symptoms</B></div> <div> Initial symptoms of green mold are similar to those of sour rot and blue mold. The small decayed area appears as a soft watery spot that is more firm than comparable stages of sour rot. White mycelium is produced on the lesion surface, and when the lesion enlarges to approximately one inch in diameter, olive green spores are produced in the center. A broad zone of white mycelium surrounds the sporulating area, and the outer region of the lesion is composed of softened rind. The entire fruit is soon encompassed by a mass of olive green spores, which are easily dispersed by any physical motion or air currents. The decay spreads very little in packed cartons, but masses of spores produced on one infected fruit can soil surfaces of healthy fruit with green-colored spores.</div> <div> <B>Control</B></div> <div> Best control of green mold is achieved through:</div> <div> 1. careful harvesting and handling to minimize injuries; </div> <div> 2. stringent daily sanitization with chlorine or quaternary ammonium of the wet line through the waxer brushes, and of fruit bins after dumping. Degreening and storage rooms should be sanitized when sporulating fruit are observed, and water in drenchers and soak tanks should be continuously chlorinated;</div> <div> 3. prompt removal of any infected fruit from the packinghouse, and NO repacking of packed cartons with fungicide-treated sporulating fruit in the packinghouse facility;</div> <div> 4. monitoring of the spore population in the packinghouse for concentration and resistance to postharvest fungicides; </div> <div> 5. spraying with benomyl (Benlate) preharvest, drenching with thiabendazole (TBZ) before degreening, washing with sodium orthophenylphenate (SOPP) and/or applying TBZ and/or imazalil on the packing line in aqueous or wax treatments; and </div> <div> 6. immediately precooling or storing fruit after packing at temperatures of 500 F or below. </div> <div> Sources:</div> <bR> <bR> <div> Brown, G. E., "Green Mold," University of Florida, Florida Cooperative Extension Service Fact Sheet PP-136, June 1994.</div> <div> Brown, G. E., Eckert, J. W. "Green Mold," in Compendium of Citrus Diseases, Whiteside, J.O.,Garnsey, S. M.,Timmer, L. W., editors. St. Paul, MN: The American Phytopathological Society Press, 1988.</div> <div> Eckert, J. W., Brown, G. E. "Postharvest Citrus Diseases and Their Control," in Fresh Citrus Fruits, Wardowski, W. F., Nagy, S., Grierson, W., editors, Westport, CT: AVI Publishing Co., Inc., 1986.</div> <div> Wardowski, W. F., Brown, G. E. "Postharvest Decay Control Recommendations for Florida Citrus Fruit," University of Florida, Florida Cooperative Extension Service Fact Sheet Circular 359-A, May 1993.</div> <div> Prepared by Eldon Brown, Mohamed Ismail and Cathy Clay October 2, 1995 </div> <div> DOC/CFF - 4 - 95 </div> <bR> <bR> <div>     e-mail   info@agscan.net   (805) 528-1492</div> <bR> <div>  <FONT SIZE="3" COLOR="#3300FF" FACE="Arial" ><IMG SRC="0cc14140.gif" border=0 width="20" height="20" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"> 2006 AgSCAN Inc.</FONT></div> <bR> <bR> <bR> </td> </tr></table></body>