- Author: Jeff Mitchell
- Contributor: Laura J. Van der Staay
A video of the soil health workshops that were held last week on Tuesday, December 10th in Davis and Wednesday, December 11th in Five Points with Jay Fuhrer, a district conservationist with the USDA Natural Resources Conservation Service office in Bismarck, ND and Brendon Rockey, a farmer from Center, CO is now available for viewing. These workshops attracted over 150 participants and generated many good ideas and interactions between attendees.
The Conservation Agriculture Systems Institute (CASI) thanks all who took part and also extends warm gratitude to Jay and Brendon for taking the time to share their experiences with California Ag stakeholders.
During this season, Carlos Crisosto, CE postharvest physiologist, Kearney Agricultural Research & Extension Center and the UC Davis Plant Sciences Department, is often asked how to determine maturity, as well as best practices for harvesting and storage of ‘Fuyu’ persimmons. ‘Fuyu’ persimmons completely lose their astringency before harvest and can be consumed while they are still firm. Harvest time is usually determined according to the fruit color and size. The best method of harvesting is to clip the fruit from the tree with small clippers (orange clippers), leaving the calyx attached to the fruit. It is also possible to snap the fruit from the tree but this practice is not recommended as it may injure the fruit and adjoining shoot. During harvesting and packaging, fruit must be handled carefully to avoid bruising, which can result in undesired marking as the fruit ripens. Penicillium, Botrytis and Cladosporium fungi may infect ‘Fuyu’ persimmons during storage, especially, if the skin has been damaged during postharvest handling.
‘Fuyu’ persimmons are very sensitive to chilling injury which is expressed by accelerated fruit softening, flesh browning, and translucency (jelly-like consistency) during and after storage. These symptoms appear more severe after 2-4 days at 68oF (20oC) following storage. Chilling injury is more rapid and severe at 41oF (5oC), especially, combined with ethylene exposure. Previous studies led by Dr. Kader demonstrated that exposure to 1 and 10 ppm ethylene at 68oF (20oC) resulted in accelerated softening to less than 4 pound-force ( the limit for marketability) after 6 and 2 days, respectively. Exposure to 1 and 10 ppm ethylene at 41oF (5oC) will induce fruit firmness below 4 pound-force (soft) after 15 and 8 days, respectively. Therefore, the use of 1-MCP, ethylene removal and/or exclusion of ethylene during packaging and storage at 32oF (0oC) operations is strongly recommended for maintaining quality and extending ‘Fuyu’ persimmon storage life potential.
To help growers, packers, shippers and handlers of Central Valley crops, Carlos Crisosto, CE postharvest physiologist, Kearney Agricultural Research & Extension Center and the UC Davis Plant Sciences Department, published the Central Valley Postharvest Newsletter (CVPN). CVPN archives contain summarized information relevant to fresh fruit growers, packers, shippers and handlers. The archives are available from the UC KARE and UC Davis websites.
Other online resources that Crisosto recommends include:
- The UC Davis Fruit & Nut Research & Information
- A draft version of the forthcoming revision to USDA Agricultural Handbook 66 (Commercial Storage of Fruits, Vegetables and Florist and Nursery Stocks)
- Postharvest information site of the Food and Agriculture Organization of the United Nations
- World Vegetable Center Postharvest Information
- Postharvest Education Foundation (training in postharvest technology)
- Production and Handling of Avocado
- University of Florida Postharvest Group, including citrus resources
- University of Florida Citrus Resources
- California Citrus Research Board – supported research reports
- Washington State University Postharvest Information Network (emphasis on apple, pear, and cherry)
- North Carolina State University postharvest publications
- Sydney Postharvest Laboratory information
- Chain of Life Network® website with recommendations for the care, handling and marketing of floral crops
Two unique workshops on soil quality will be provided this week. One will be held on Tuesday,
December 10, 2013, on the UC Davis campus in 3001 PES (Physical and Environmental Sciences) at 11:00 am and the other will take place in Five Points on Wednesday, December 11, s013, also at 11:00 am.
The sessions will feature Brendon Rockey, a farmer from Center, CO and Jay Fuhrer, an NRCS District Conservationist from Bismarck, ND. They’ll be leading the workshop that will also include a lunch and a follow-up discussion.
For further information, please contact Jeff Mitchell, CE Cropping Systems Specialist, Kearney Agricultural Research & Extension Center, at (559) 303-9689 or firstname.lastname@example.org.
- Author: Jeannette E. Warnert
Daane and his research associates followed moth populations in organic and conventional fields to document this observed change and determine if there were any specific causes for increases in raisin moth densities. In a 2013 season study, UC Kearney Agricultural Research and Extension Center entomologists found that spring to early summer pheromone trap catches of raisin moths were prevalent across numerous vineyards, regardless of management practices. However, overall seasonal damage in 2013 was low.
“The primary difference between vineyard sites with or without raisin moth damage appeared to be well-timed and effective insecticide sprays,” Daane said. “One problem for organic sites may be the availability of insecticide materials that have long enough residual activity to control the larvae of adult moths entering the vineyard, and once the larvae are deep inside the grape cluster they are difficult to control.”
In addition to Daane’s report, the San Joaquin Valley Grape Symposium includes the following research updates:
- Rootstocks for raisin production by Sonet Von Zyl, Fresno State University
- Raisin production canopy management by Matthew Fidelibus, UC Cooperative Extension specialist in the Department of Viticulture and Enology at UC Davis, based at the UC Kearney Ag REC in Parlier
- Raisin grape breeding program by Craig Ledbetter, USDA Agricultural Research Service, based in Parlier
- Economics of producing raisins, by Annette Levi, Fresno State University
- Grapevine trunk diseases and grower survey
The symposium begins with registration at 7 a.m. and concludes following lunch at 1 p.m. at the C.P.D.E.S. Hall, 172 W. Jefferson Ave., Easton, Calif.
Registration is $15 in advance and includes lunch. Registration at the door is $20. To preregister, send the names of attendees and a check payable to UC Regents for $15 each to San Joaquin Valley Grape Symposium, 550 E. Shaw Ave., Suite 210-B, Fresno, CA 93710. To register with a credit card, fill out the online registration form at http://ucanr.edu/sjv2014.