- Author: Cris L. Johnson
The meeting focused on updating growers and interested members of the public on subjects relevant to producing strawberries in Ventura County and other areas. The agenda included topics on:
- Strawberry cultivar performance and research updates
- Management of Macrophomina and Fusarium and treatments
- Irrigation practices for strawberries in Oxnard and Watsonville
- Water quality monitoring results for strawberry production fields in Ventura County
- Fertility research updates
- Management of mites, thrips, corn earworm and spotted wing Drosophila
- California Strawberry Commission update on research and regulatory issues pertaining to strawberry production
The production meeting included lunch and attendees could receive continous education credits from the Department of Pesticide Regulation.
For a list of this and other strawberry meeting presentations online, please click here.
Strawberry production growers face many challenges. One such challenge is strawberry anthracnose, which is caused by Colletotrichum acutatum. This plant pathogen is often undetectable on transplants purchased from nurseries for the planting season, but can become very destructive after transplanted into the field.
UCCE’s Oleg Daugovish and collaborators researched this disease and how to best reduce risk and loss. The researchers studied irrigation systems effects on fruit yields, canopy size, and crown tissue infection to determine best management practices.
Their research has recently been published in the American Society for Horticultural Science Journal. You may view the abstract at this site. The full text may also be viewed by following a link on the abstract page. The full article may also be viewed in the UC Cooperative Extension, Ventura County office.
Written by a team of authors, including UCCE Ventura County’s Oleg Daugovish the recently published Organic Strawberry Production Manual is full of fantastic information.
In 2009 organic strawberry sales in California totaled $55 million, up substantially from $2 million in 1997. Organic production is projected to continue to increase, and this detailed how-to guide will help those working with the organic production of strawberries.
This publication is designed for commercial growers, pest control advisors, consultants, marketers, industry professionals and other interested in the organic growing and certification process.
- Selecting plant varieties
- Managing crops
- Identifying and managing pests and diseases
- Making the switch from conventional to organic growing
- Pursuing organic certification
- And much more
To learn more, please visit this page of the UC ANR Catalog. To receive 10% off your online order, please use promo code, PRVEN56. In addition to your discount, a portion of the sale will help support local programs.
- Author: Oleg Daugovish
We have many highly salt sensitive crops in Ventura County: strawberry, avocados, blueberries. Rainwater, the purest kind, is excellent for leaching salts, but, in years with low rainfall, salt accumulation and resulting toxicity is a big concern.
Plant reaction to salts varies among varieties, stages of growths and environmental conditions and, perhaps most importantly, with the type of salts that they are exposed to. We typically determine salinity of water and soil by measuring Electrical Conductivity (EC): the more salts are present the greater is the capacity to conduct electric current. In fact, there are guidelines for most crops that show at which EC level you would expect negative effects on plant growth and productivity. Yet there seems to be a discrepancy between the guidelines and what actually happens in the field. For example, University of California (UC) guidelines suggest that strawberry injury and yield reductions can occur at EC=1 dS/m. However, in several Ventura County fields we have healthy productive strawberry in soils with EC >4 dS/m. These large differences in tolerable EC levels result from the fact that the guidelines were developed using sodium chloride, while Ventura county soils/waters most frequently have calcium and sulfates as primary components of EC. Recent studies at UC Riverside showed the specific negative chloride effect on strawberry fruit production, while studies elsewhere have documented that sodium can also be more harmful than other ions such as calcium and potassium. Because we have calcium-rich soil, and even irrigation water often contains calcium sulfate, our crops can manage well even with EC levels well above 1 dS/m. In fact calcium and magnesium help to counteract the negative effects of sodium in the soil salt solution.
In a demonstration, we wanted to show that a very salty water (EC=20 dS/m) will have different effects on mature strawberry plants depending on the ion composition of the salts in that water. Indeed, after four days of watering with sodium chloride solution, the plants had severe injury symptoms and were dying. However, the same salt concentration of potassium sulfate only resulted in slight marginal leaf burn and mild stunting. Plants irrigated with distilled water (that imitated rain water) looked perfect, of course.
The important points of these demonstrations and field evaluations were:
- EC values in water or soil analyses only show total salinity and one needs to look at specific ions in the report to evaluate the potential effects on sensitive plants.
- Sodium and chloride are a lot more damaging that potassium and sulfate and we’re planning to evaluate several other salts and develop realistic thresholds for safe strawberry production in their presence.
- At high concentrations in the root zone fertilizers (such as potassium sulfate, a ‘safer’ salt) can injure plants and reduce their productivity
- Typical irrigation with drip lines placed between planting rows does not affect salts in the root system, unless excessive amount of water are applied to induce leaching.
UC Farm Advisor Oleg Daugovish will hold an Irrigation field day Thursday, April 19 from 9:00 am to 11:15 am.
Scheduled topics include:
- Update on conditional waiver and requirements for irrigated lands in Ventura County
- Evaluation of three differing irrigation regimes in California strawberry
- Salts and soil analyses in strawberry beds under different irrigation regimes
- Soil test results interpretation and corrective management
- View experiment plots onsite
VCALIG educational credits have been requested from the Los Angeles Regional Water Quality Control Board.
There is no cost to attend. If you have questions, require translation into Spanish, or to register please contact Oleg Daugovish at 805.645.1454 or email@example.com. More information can be found on the agenda.
In the event of rain, the meeting will be held at the UCCE Conference Room located at 669 County Square Drive in Ventura.