The Citrus Research Board provided funding for a new citrus fruit grading system for Lindcove.  The Compaq system has three sets of cameras (InVision 9000, ultraviolet, near infra-red) that will allow us to do more than just size, count and grade the fruit, but also measure length and width, volume, density, scarring damage, rot, puff and crease, dryness and Brix.  The highly advanced software will record measurements for each individual fruit which will allow us to run correlations between all of these parameters.  The result is that we can determine which rootstock and scion (variety) combinations give the perfect size, sweetest taste, and best ripening fruit.  We will also be able to train the software to recognize various pest damages and so demonstrate which pesticides best protect the fruit from damage.  The system arrived on September 29th and we are very excited about the many new studies that it will support for researchers at Lindcove.  Thank-you to the citrus industry! 

Staff Research Assistant John Bash from the Citrus Clonal Protection Program (CCPP) at UC Riverside directs the fall budwood cut at the Lindcove Research and Extension Center.  The citrus trees that provide the budwood are grown inside Lindcove’s protective screened buildings and distributed from there to the nursery industry.   The screening prevents insect vectors such as aphids and psyllids from reaching the trees and potentially infecting them with diseases.  The CCPP screenhouse trees are tested several times per year to ensure they are free of all known citrus diseases.   Raul Gonzalez, a retired Lindcove SRA, still enjoys assisting with the budwood cuts after 38 years of service to the University of California.

UC Riverside researchers Mikeal Roose and Tracy Kahn are evaluating seed content in Valencia oranges as part of a mutation breeding project to find new cultivars with lower seed content.  Budwood of the existing Olinda Valencia cultivar was irradiated to induce mutations and trees were then propagated from the treated buds.  The resulting trees are grown at Lindcove Research and Extension Center and then fruit from each tree are cut to determine seed content.  Trees that produce many fruit with few or no seeds will be selected and a pathogen-free budsource will be established by the Citrus Clonal Protection Program.  This budsource will then be used to propagate trees for replicated trials at Lindcove and elsewhere in California.

The Citrus IPM research team at Lindcove REC tests the efficacy of pesticides and provides recommendations to pest control advisers on strategies for managing citrus pests in the San Joaquin Valley.  A long, wet spring has resulted in exceptionally high citricola scale populations this summer, and control is expected to be difficult due to the insect’s known resistance to organophosphates.   Heavy infestations of citricola can dramatically limit fruit set.  Three experimental insecticides are currently being tested for effectiveness and possible registration, as well as a dozen or more registered pesticides.  The goals of the citricola trials are to find insecticides that achieve at least two years of control between sprays and that have minimal impact on natural enemies that help to control citricola scale and other pests. Results of these and other trials are published annually in the journal Arthropod Management Tests.  Informative pest-specific information is available online at http://ucanr.org/sites/KACCitrusEntomology/