- Author: Jeannette E. Warnert
Larry Williams, professor in the Department of Viticulture and Enology at UC Davis, made use of a large, wine grape variety trial at Kearney to determine the contribution that water relations and vine hydraulics have on growth differences among grapevine cultivars. The study will help determine the most appropriate parameters for managing irrigation across divergent varieties and growing locations.
Following Williams' field demonstration, the presentations move indoors and include:
- Ecology of mycotoxin-producing aspergilli in raisin vineyards by Teresa L. O'Keeffe and Jeffrey D. Palumbo of USDA Agricultural Research Service
- Effects of pre-harvest calcium chloride and chlorine dioxide applications on fruit quality of crimson seedless table grapes by Matt Fidelibus, UCCE specialist in the Department of Viticulture and Enology at UC Davis,
- Wood disease management options for grapevines in the San Joaquin Valley by Philippe Rolshausen, UCCE specialist in the Department of Botany and Plant Sciences at UC Riverside
- Movento in table grapes: understanding use patterns and expectations by David Haviland, UCCE advisor in Kern County
- Understanding wine oxidation by Andrew Waterhouse, professor in the Department of Viticulture and Enology at UC Davis
Kearney-based Fidelibus hosts the event every two years at the field station, 9240 S. Riverbend Ave., Parlier. For the 2013 event he has applied for 1.5 hours continuing education credit.
Fidelibus will be tweeting about GrapeDay 2013 from his Twitter account @grapetweets using the hashtag #ucgrapeday. All Grape Day participants and attendees who use Twitter are encouraged to participate in discussions related to the event using the hashtag #ucgrapeday.
Attendance at UC Grape Day 2013 is free, but online advance registration is requested for planning purposes. To register, go to http://ucanr.edu/sites/grapeday.
- Author: Jeff Dahlberg
KARE's new solar energy project has been completed. PG&E did their final safety checks for the new 42 kW solar system located at our Postharvest Facility. This brings KARE's solar output to about 65 kW. Special thanks to JKB Energy, Bob Ray, Patrick West, Andy Padilla, Santiago Aldana, Rudy Gonzales, Dan Mulligan, and Dale Pattigan for all of their hard work in helping to get this done. KARE will continue to get more green technologies on the Center. We continually strive to lower our carbon footprint and look at new and innovative ways to bring green technologies to our farming operations.
- Author: Laura J. Van der Staay
The City of Parlier’s Earth Day celebration on March 30th attracted about 2000 attendees. Events included a tree planting, Easter egg hunt, family walk, folk dancing, zumba dancing, free raffles for prizes, games for youth, and face painting. Representatives from many local service organizations had booths that provided families with free items ranging from food to dental screening. KARE’s booth provided 1000 strawberry crowns and 2500 leaf lettuce transplants to the public. Youth from the local Leo club helped with handing out the plants and discussing the benefits of eating fruits and vegetables.
- Author: Laura J. Van der Staay
In 2003, the Polyphagous Shot Hole Borer (PSHB) was observed in Southern California. This beetle has a Fusarium sp. symbiont that causes susceptible host tree damage. The PSHB appears to be established in Los Angeles, Orange, and Riverside Counties. In the Los Angeles area, PSHB has attacked over 200 species of native, ornamental and horticultural trees, including the native Coast Live Oak, California sycamore, and about 57% of the commonly used street trees in the area. Avocado trees are susceptible; the beetle and fungus have been found in several backyard avocado trees as well as some commercial avocado orchards in Los Angeles and Orange counties. The PSHB has caused severe damage to commercial avocado orchards in Israel, and is a threat to California’s avocado crop which is worth about $460.6 million and accounts for about 87% of the US production.
To better understand the biology of and potential management strategies for the PSHB Fusarium complex threatening California’s avocado trees, Mary Lu Arpaia, Subtropical Horticulture Extension Specialist in the UC Riverside Botany and Plant Sciences Department and Kearney Agricultural Research and Extension Center, and David Obenland, Plant Physiologist, at USDA-ARS in Parlier, California, visited Israel in March, 2013. The PSHB is an invasive pest in Israel and was found in Israel’s commercial avocado orchards in 2009. The PSHB in Israel is causing serious damage, and Israeli research may help us develop detection and management strategies in California.
Biology and Behavior: A visit with Drs. Zvi Mendel and Stanley Freeman, Israel’s lead PSHB researchers provided insight into research on the biology and behavior of the PSHB Fusarium complex. Drs. Mendel and Freeman contend that even though the beetle uses several tree species as hosts, it is monophagous, only feeding on the Fusarium symbiont. According to their research, the beetle’s reproductive cycle in susceptible trees is: the adult pregnant female beetle bores through a tree’s bark, creates galleries under the bark, infests the galleries with a Fusarium fungal symbiont carried in the adult beetle’s mycangium (a specialized structure at the back of the jaw), and lays eggs in the galleries. Larvae are mostly female. While the larvae develop, the Fusarium sporulates. The developing larvae eat the fungus, develop into adults in about a month, and mate while in the gallery. The pregnant females exit the gallery through exit holes in the bark. To survive, the emerged pregnant female has about 48 hours to find a suitable host location and continue the life cycle.
Hygiene: The geographic area where the beetle is found in Israel appears to be expanding, even though the infested avocado trees in the primary infested area were destroyed. The PSHB is thought to have been transported in bins originating from the infested area. A best practice for California growers and packers will be to use clean bins and ensure that there is no vegetative matter in the bins prior to transport. This practice will also help reduce the spread of avocado thrips and persea mite.
Chemical control of the beetle or the fungus: There has been limited success in controlled lab situations, but field applications are not effective. So far, no effective chemical control technologies have been developed for the beetle.
Infestation: A mature orchard that was infested approximately 5 to 6 years ago became heavily infested within 2 to 3 years, and will be bulldozed. Infestations may require bulldozing orchards.
Detection: Mature avocado orchards with heavy infestation have severe limb dieback, many broken branches littering the orchard floor, dropped mature fruit, abnormally small mature fruit, and sugar exudates caused by the bore holes. A 2-year-old infested orchard did not exhibit very much limb dieback; when infestation of young trees is observed, it is usually on the base of the trunk (found in either the rootstock or the scion wood).
Spread to native and landscape hosts: Israel has seen the spread of the beetle to native oaks and the box elder. California will need to educate the public to help safeguard our native and landscape trees from the spread of the PSHB and Fusarium complex. Native and landscape tree infestations may make it difficult to control the spread of infestations into commercial avocado orchards.
California outlook: California must be diligent in looking for tree infestation. The avocado industry is working with the landscape industry and forestry service in California to understand the rate of infestation and range of susceptible hosts. Funding for surveys; understanding the beetle and fungal biology; developing control strategies, technologies and practices; and basic work on the origin of the beetle is essential. California researchers should collaborate with and learn from their Israeli colleagues.
- Author: Laura J. Van der Staay
More than 1,600 third-graders and 330 teachers and chaperones from 24 Fresno County schools attended Farm and Nutrition Day March 22 at the Big Fresno Fairgrounds. Attendees had the opportunity to tour 50 stations with educational handouts, experiential workshops, presentations and demonstrations. Fresno County Farm Bureau organized the event with the assistance of several presenter groups, sponsors and volunteers, including two UC Agriculture and Natural Resources units.
KARE provided short presentations on what it takes to be a healthy plant and what it takes to be a healthy person, followed immediately by workshops where the students planted leaf lettuce transplants to take home and enjoy. This workshop was made possible with donations and volunteers. Valley Soil & Forest Products donated soil, The Plant People donated pots, and Greenheart Farms donated lettuce transplants. Ten volunteers helped ensure that all of the participants were able to pot up and take home leaf lettuce plants.
Fresno County UC Cooperative Extension provided nutritional presentations and demonstrations. Fresno’s community 4-H clubs brought farm animals to interact with the mostly urban students. Richard Molinar, UC Cooperative Extension advisor in Fresno County, small farm program, displayed Southeast Asian vegetables and discussed Southeast Asian culture with the students.