Subtropical Fruit Crops Research & Education
University of California
Subtropical Fruit Crops Research & Education

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Annual Avocado Meeting

             California Avocado Society's

                  2017 Annual Meeting

This year marks our 102nd Annual Meeting and it will be held

in Ventura County on October 20 - 21, 2017

949-940-8869 Office
949-276-9721 Fax


Must Download 2017 AM Flyer & Registration to Fill out Form

**Register & pay online or mail or fax the form with payment.

**Late fee of $25 will be added on registrations after

Monday, October 16th.



Friday Field Tour

Registration at Hansen Agricultural Center

(Directions to the fields will be given at Registration)

Best to register before October 20th


Fruit Growers Laboratories: Water, Leaf and soil analysis technologies along with some pathology analysis.

Brokaw Orchard:  High Density. Management changes over time.

Dominguez Orchard: High Density. Management and pruning.

Friday Evening President's BBQ Reception

At Limoneira Ranch Headquarters.

It will be a special evening as members and friends network and share industry information.


(Download to Hansen Agricultural Center Directions)

(Linke to BBQ Reception Direction to Limonira Ranch HQ)

Saturday Annual Meeting

Held at Four Points by Sheraton Ventura Harbor, CA

1050 Schooner Drive, Ventura, CA, 93001

We have a great line up of speakers planned


Scott Bucy

Vice-President Fruit Growers Laboratories

Soil and Plant Analysis--Common and Not So Common Problems.


Dr. Raquel Folgado

Cryopreservation Researcher, The Huntington

Cryopreservation of Avocado Germplasm and New Technology Spin-offs for Propagation and Breeding.


Consuelo Fernandez

Director of International Cooperation, Brokaw Nursery

Gem Variety Management, and New Rootstocks.


Dr. Peggy Mauk

UCR Director of Ag Operations and CE Subtropical Specialist

Rootstock Trial Progress.


Brittany Collins

Owner and Chief Pilot, HawkEye Imaging

Remote Sensing Technology—Now and in the Future.


M. Cristina Léon 

CAS Board Member

Highlights of the CAS tour to Michoacan, Mexico.


Grower Panel

Shawn Martin, Organic Grower Carpinteria; Kevin Ball, Ag Land Services; Ed McFadden, Orchard Manager.

Moderated by Susan Estrada, Newsline Editor.

Awards: Oliver Atkins Award and Award of Honor.

You will find the pricing and detailed information for

Saturday's agenda, Friday's tours and President's reception on the registration pamphlet.


For the CAS's special rate rooms at the Four Points by Sheraton

for single/double rate $129 

Please call in-house reservations: 

(805) 658-1212 ext. 1290 (Mention "California Avocado Society" for the discounted rates.
Cutoff date for the special rates will be September 27, 2017.


Posted on Tuesday, October 17, 2017 at 10:33 AM
Tags: avocado (186), disease (45), field trip (1), Persea (5), workshop (1)

That Black Hearted Pomegranate

Pomegranate (Punica granatum) is a specialty crop now grown on more than 10,000 acres in California.  Pomegranate production has increased for both fresh market and juice in the last several years, and with this increase, random internally rotted fruit has become more noticed. The outside of the fruit looks perfectly fine, but internally the fruit is rotted and the arils (the flesh covered seeds that are eaten and juiced) are black. Pretty disgusting. Some fruit recently has shown up at harvest and the grower was unaware of the problem until the fruit was opened by a customer. The only difference between good fruit and affected fruit is that the blackhearted fruit is a bit lighter in weight. The absence of external symptoms makes the diagnosis of the disease very difficult, and consumers encountering the disease may change their perception of the pomegranate's many health benefits.

Initially, it was thought that the disease was caused by various fungi that can decay only the arils. However work by Themis Michailides from UC Kearney REC has shown that after inoculation of pomegranate flowers and developing fruit that the main cause of black heart is Alternaria spp. These fungi are very abundant in nature and cause diseases in a multitude of crops. Another fungus that is also isolated from pomegranate with black heart is Aspergillus niger. However, the decay caused by A. niger is softer than that caused by Alternaria and results in exuded juice. In addition, another major difference between black heart caused by Alternaria spp. and that caused by Aspergillus is that the latter decays both arils and rind of fruit and frequently symptoms reach the outer surface of fruit, which helps in the diagnosis of the disease. Inoculations with Alternaria spp. reproduce the typical symptoms of black heart (internal decay of the arils without any external symptoms).

Inoculations periodically with Alternaria spp. showed that most of the infections occur at bloom time and that spores of the fungus that are introduced into the fruit (puncturing from thorns, hemipteran feeding like aphids and stink bugs, or cracking) can result in black heart. The current research focuses on the identification of the various species of Alternaria that cause black heart, the understanding of the infection process, and the development of procedures to manage the disease.

Alternaria alternata and related species commonly occur on plant surfaces and in dying or dead tissues of plants. The pathogens overwinter on plant debris in or on the soil and in mummified fruit. The spores are airborne and can be carried to the flowers with soil dust. Infections may also start from insect and bird punctures on fruit. Research in the San Joaquin Valley showed that the petal fall stage seems to be the most susceptible stage when most of the infection occurs. However, infection can occur throughout the long bloom and fruit development periods.

Estimated losses are usually less than 1% but can be up to 6%.

So how does a grower reduce black heart? Fungicide coverage has been a problem for bloom fungicides, but Michailides has shown some promising new materials. Good orchard management practices, such as dust control and sanitation (removal of old fruit and dead branches), may reduce the incidence of the disease. Infected, healthy-appearing fruit may be dropped to the ground by gently shaking the tree at the time of harvest. Avoid water stress and overwatering that may result in fruit cracking.

Thorough sorting and grading of pomegranates for discoloration and cracking can help avoid packing diseased fruit.

See the Themis' slide show:

Posted on Monday, October 16, 2017 at 7:05 AM

What's More Delicate than an Egg?

 A fig. A yellow fig. A most delicious 'Kadota' fig.  A piece of fruit that falls apart easily and shows every nick, scrape and bump.


And it doesn't take much to reduce a fig to something that is not very attractive to a consumer.

There have been all manner of packing materials that have been devised for shipping fresh figs. Nestled in individual packing hollows they can be shipped to arrive in pretty good condition.


'Bursa Black" which is a 1/4 pound fig grown in the Bursa region of Turkey is shipped to large cities in Europe and because of careful fruit selection and packaging, arrives in excellent shape at the delivery point

Some of these shipping containers pack for individual display, making it easy for the seller to keep from damaging the fruit when removed from the container.

The ultimate shipping container that has been developed for delicate fruit is a "suspended tray" container which floats the fruit to its destination.  It's somewhat pricey, so the value of the fruit will determine its value to the shipper.  A description of the tray using pears and avocados follows:




                                  J. F. Thompson, D. C. Slaughter, M. L. Arpaia

Bartlett pears and Hass avocados are subject to transport vibration damage and their susceptibility to damage
increases as the fruit soften during ripening. Firm fruit,greater than 50 SIQ units (13‐lb penetrometer firmness) for
pears and greater than 65 SIQ units (3.0‐lb penetrometer firmness) for avocados, could be shipped in a wide variety of
conventional packages with little transit vibration damage.However softer fruit sustains significant transit vibration
damage when packed in conventional packaging systems and subjected to severe in‐transit vibration conditions common to cross‐country transit in the United States. This study demonstrated that softer fruit was protected from transit vibration damage when packed in a suspended tray packaging system. The study showed that even eating‐ripefruit could be shipped in the suspended tray system with transit vibration damage not significantly greater than nonvibrated control fruit.

But hey, an egg carton may work just about as well.


Posted on Thursday, October 12, 2017 at 4:37 PM
Tags: apricot (1), clam shell (1), delicate fruit (1), display (1), fig (4), packaging (1), peach (3), ripe (1), soft fruit (1), transport (1), tray (1)

Avocado Educational Grower Seminar Series Continues to Progress and Benefit California Growers

California produces about 90 percent of the nation's avocado crop. California avocado growers compete in both the domestic and international markets with countries with much lower costs of production and labor availability. To stay competitive will require more efficient farming strategies and a significant increase in productivity on the part of California growers, especially with the increase of water costs and labor constraints. To adapt, growers need to dramatically increase yield per acre using the same amount of water or less. Evolving farming practices and new information is essential for growers to stay competitive with the world market.

 Since 1995, University of California Cooperative Extension, in collaboration with the California Avocado Society and California Avocado Commission has developed a seminar series to help avocado growers. Each seminar is tailored to each specific growing region in the state: Riverside and San Diego Counties, Central Coast, and northern Central Coast. As part of the educational series, growers and stakeholders are exposed to various topics: economics, pest management, water quality and usage, soil science, pruning techniques, bio-control, Integrated Pest Management, salinity, labor, and harvesting, etc. The audience has a say in what topics will be discussed, and we have had positive feedback in all three locations. Per stakeholder request, round table discussions and field tours have also been incorporated into the program. These seminars have gained a positive reputation amongst growers and continue to impact the industry in a positive manner.

Seminars provide new information that growers share Surveys determined that these seminars address current issues affecting avocado growers in their growing regions and expose them to new skills and knowledge, encouraging change in current cultivation practices. For example, subjects such has high-density plantings, rootstock selection, and salinity management help growers maximize production. In the most recent survey (8/2017), data suggested that as many as 52 percent of the attendees come to the seminars with little to no knowledge on some of the subjects presented and as many as 73 percent of the attendees leave the seminars with either “quite a bit”, or a “complete understanding” of knowledge from the material. In addition, more than 50 percent of the clientele that attended the seminar said they are likely going to share the material learned that day with as many people as possible (10+ people). This assures that the information given is circulating and reaching those who cannot physically attend the meetings. The collected survey information shows a positive outcome and assures the success of the educational seminar series.

Seminars are held January - August of every year - Keep an eye out for next years line up!

Posted on Thursday, October 12, 2017 at 4:20 PM

What is Pollinating that Plant?

You always wanted to know what pollinated rambutan, litchi, blueberries and all those other plants dependent on insect pollen movement?  O yes, and also what is pollinating avocado?

Insect Pollination Of Cultivated Crop Plants

by S.E. McGregor, USDA

Originally published 1976

The First and Only Virtual Beekeeping Book Updated Continuously.

Additions listed by crop and date.

This book is out-of-print, but can be found on-line at ABE Books and then you can get the images that are missing from the online version of the book

This is an old book with a lot of old information, but a lot of it is still good.  There is definitely more up-to-date information, but this is a good starting point.  For avocado, another good source, or course is AvocadoSource which also has quite a number of articles on pollination of other tree species

Recently a group of UC Riverside researchers met to align themselves around the topic of pollination - The biology, effects, interactions of the various pollinator and pollinizers and how they are affected by our environment and how we might be able to manage them better.  The participants in this pollination group have all manner of expertise and hopefully their interaction will bring a synergy of understanding to this very complicated subject.

Photos:  Syrphid (hover) fly, bumblebee, honeybee, thrips carrying pollen

Posted on Wednesday, October 11, 2017 at 6:15 AM
Tags: beetles (3), biocontrol (6), nectar (4), pollen (5), pollination (11), pollinators (9), pollinizers (2)

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