Ventura County Farm Advisor Ben Faber is currently on sabbatical in Turkey. Today Ben shares a little about his studies.

Adana, Turkey is along the Mediterranean Sea, near the middle of the country, and is where I plan to spend the next 11 months studying and doing research.  I am at Cukurova (pronounced Chuckorova) University which has collections of avocados, citrus, figs, mulberries and pomegranates.  I came here because as a Mediterranean climate, it grows similar crops to California.

I had not realized that a Mediterranean climate could be so hot and humid, though.  What defines a Mediterranean climate is one that has winter rain and summer drought and mild winter temperatures.  The temperature at 6 AM in Adana is 37 C (98.6 F) and the humidity hovers around 75%.  Most businesses do not have air conditioning, but they all have heaters.  Most of the ‘Hass’ avocado trees do not look good, so I guess it is going to get cold this winter.

It is hot now, though, but that’s what makes the citrus grow, and grapes and figs and wheat and plums and apricots and corn and cotton that grow all around on the Cukurova Plain, once called the Cilician Plain.

The University is the largest agricultural school in the country with 45,000 students in diverse departments, such as horticulture, soils, and engineering, but also medical, dental, biotech, letters and sciences and other schools.  The town of Adana has 1.5 million people, is about 20 miles from the coast, is at about the same latitude as San Francisco and has all the modern conveniences of any California town.  Plus, it has a great bus system.

I am working with faculty from different departments on different trials.  Two are on citrus; evaluating different rootstocks for iron deficiency and a chemical evaluation to control leaf flush in citrus.  This latter trial is to reduce the new tissue that is so attractive to Asian Citrus Psyllid.  In avocado, we are looking at different girdling times and styles for their impact on fruit set and yield.  They have used a double girdling technique here on various tree crops for years and found that the double ring has effects that a single ring does not have.

Another trial is looking at different fig varieties as rootstocks, again to evaluate for resistance to iron deficiency.  Figs world-wide are grown from cuttings, not grafted, because they root so easily.  Having a rootstock that can handle the high pH soils that we have in coastal southern California could benefit a new industry in our State.

I am also working with the curators of the pomegranate and mulberry collections to better understand how those crops are grown here and also getting out meeting local growers of these crops.

The landscape here is fresh with new plantings, as far as the eye can see.  It is really a dynamic agriculture with farms that look every bit as well cared for as those in California.  Many of the local growers I have met have attended this University and several have studied in Europe and the US.  My English gets me by, and when I get lost, people are good at steering me straight.

Adana is famous in Turkey for its kebab, a grilled, ground lamb that is served with lemon, onion, rice, flat bread, roasted peppers, mint, and salad.  And everyone asks if I have eaten Adana kebab.  Yes, I have, and it is wonderfully fresh food.

Cukurova plane (photo by Ben Faber)

Cukurova University Campus (photo by Ben Faber)

The Asian Citrus Psyllid (ACP) has recently received a lot of media coverage and for good reason.  ACP carries the deadly Huanglongbing (HLB) bacteria, the most serious citrus plant disease in the world.  The disease kills all varieties of citrus trees and related plants such as orange jasmine and Indian curry leaves. The psyllid, about the size of an aphid, does not always carry HLB, but once an ACP feeds on an infected plant the psyllid will carry the disease for life to each plant on which it feeds.

What is particularly troubling about this pest-disease complex is that it can take years for the infected citrus trees to die; therefore, owners of the infected trees may not be aware they have the disease.  While fruit from infected trees can be bitter, misshapen, and inedible, the tree stays up and can continue to be fed upon by psyllids, causing HLB to spread further.

People and our global economy are moving this insect. ACP has spread through Asia, parts of the Middle East, South and Central America.  It has been found in Mexico, Hawaii, Texas, Louisiana, Georgia, Alabama, South Carolina, Florida and arrived in southern California in 2008.  None of the ACP’s found in California have tested positive for HLB.  However, it is highly likely that HLB-infected plants, brought from infected areas, are already here.

What can you do?  Do not bring in plant materials from areas known to be infected with ACP.  If our area becomes infected, do not move any plant materials out of our area. Purchase only certified pest- and disease-free trees from a reputable nursery.  Stay informed. Check your trees regularly for signs of ACP. Report suspected ACP and/or HLB to the County Agricultural Commissioner or the California Department of Food and Agriculture (CDFA).

Today we share a recent press release. The Ventura County Master Gardeners are working hard to educate home gardeners about the Asian citrus psyllid and the deadly bacterial disease it carries.

Residents of Ventura County are asked to be on the lookout for a tiny insect that could wipe out California’s citrus industry — and with it, every lemon, lime, orange, grapefruit and mandarin tree in every urban and suburban yard.

This tiny insect, known as the Asian citrus psyllid (SIL-lid), carries a bacterial disease that is harmless to humans but inevitably fatal to all varieties of citrus. There is no treatment or cure. The disease has already destroyed millions of trees in citrus-producing regions around the world, including Florida.

The pest has been found in San Diego, Imperial, Orange and Los Angeles counties, and is expected to reach Ventura County this year. The disease is not far behind — infected trees have been found in western Mexico, and the disease is moving steadily closer to California.

The only way to stop this plague is to quickly find and kill the insect pest whenever it reaches a new area. If you have citrus trees in your yard, inspect them often. The insect feeds on the new leaves and stems of all citrus varieties. Twisted, stunted new growth is a sign your tree may be infested by the psyllid, which looks like a small, brown grain of rice. You may also notice the tiny nymphs feeding on tender young growth. Look for sticky white secretions, like honeydew, or sooty mold clinging to the leaves.

If you think you have spotted this invasive pest in your trees, report the sighting immediately by calling 1-800-491-1899.

For more information about the pest and the disease it carries, call the Ventura County ACP-HLB Task Force at 805-535-8641, or visit their Facebook page. 

A team of scientists from the Agricultural Research Service of the U.S. Department of Agriculture and the University of Florida’s Indian River Research and Education Center are studying the use of periwinkle (Catharanthus roseus) to fight Huanglongbing (HLB). HLB is a bacterial disease that threatens citrus crops worldwide. The bacteria is spread by the Asian Citrus Psyllid.

The scientists infect the periwinkle plants with HLB and then run experiments on the diseased plants in an effort to find a way to return the plants to good health. They have used nutrient and soil treatments to regenerate infected plants and have placed cuttings in chemical compounds to search for HLB treatments.

Further information on this research and more can be found in the May 2010 edition of the Topics in Subtropics Newsletter on our website.

Yellowing leaves is one symptom of HLB

Periwinkle shows promise for solutions

to problems caused by HLB