Identifying and Harnessing HIPPOs for Hop and Grape Pest Management
Dr. David G. James and Tanya Price, Entomologists, WSU
HIPPOs might seem to be a strange research focus for entomologists, but our HIPPOs put some bite into pest management. These HIPPOs took center stage as the result of some potentially groundbreaking field studies in biological insect pest management at the Washington State University (WSU) Irrigated Agriculture Research and Extension Center (IAREC) in Prosser last summer.
The Meaning of HIPPO
HIPPO stands for “Herbivore-Induced Plant Protection Odor,” a concept we introduced as “Herbivore-Induced Plant Volatiles (HIPV) to AENews readers in the November 2002 issue (James and Price 2002). Briefly, HIPPOs are released by plants when the plants are attacked by insect and mite pests. Each plant species tends to release a characteristic “bouquet” of aromas, which may be further modified by the type of herbivore attacking it. The function of HIPPOs is to inform natural enemies of the presence of their prey, thus attracting them to the plant being attacked and helping reduce injury. In effect, the plant under attack recruits “bodyguards” to fend off its attackers. Released volatiles therefore are “protective odors,” thus our switch to the more precise HIPPO acronym.
Taking HIPPOs into Washington Hops and Grapes
HIPPOs as an Aid to Biological Control?
HIPPO Experiments in Hops and Grapes in 2003
Encouraged by our attraction experiment results in 2002, we approached an insect lure manufacturer and contracted them to prepare a quantity of slow release sachet dispensers containing methyl salicylate. Our aim in 2003 was to see whether methyl salicylate could enhance recruitment and sustainability of natural enemy populations in a 2-acre hop yard compared to a nearby unbaited hop yard. We also set up a replicated experiment in a Concord grape vineyard using 6 blocks, each containing 65 vines, distributed randomly in the vineyard. Three blocks were baited with methyl salicylate, three were unbaited. In the hop yard, 363 dispensers were stapled to support poles in mid April, while 55 dispensers were used in each baited Concord block. Visits were made to the sites weekly and sampling of insect and mite populations conducted through a variety of techniques. In hops, we used leaf samples for pest (mite) monitoring and a combination of sticky traps and canopy shake samples for beneficial insect monitoring. In grapes, we used sticky traps for all monitoring. The results described below are representative of the data we collected; statistical comparisons are being articulated as we complete data analysis at this writing.
Hop Mites HIPPO-ed
We have monitored the methyl salicylate-baited hop yard since 1999. Despite a major commitment by the grower to encourage biological control of mites, it has been necessary to apply at least one miticide each season. In 2003, mite pressure was substantial, with hot, dry conditions prevailing. During June, mite numbers increased rapidly to a mean of 70 per leaf by mid-month. However, during the third week of June the mite numbers fell dramatically to a mean of 6 per leaf. Numbers did not exceed 10 per leaf for the rest of June, July, and August and mites were virtually absent at harvest in early September (Figure 1, top). In contrast, mites in the unbaited hop yard averaged 36 to 64 per leaf during late May and early June with no indication of natural regulation; a miticide was applied in mid-June. Other hop yards in the district also exhibited rapidly increasing mite populations during June that required chemical control before the end of the month (Figure 1, bottom). The dramatic reversal in mite population growth during the third week of June in the methyl salicylate-baited yard was unprecedented. In our experience, such a decline in hop mite populations during hot dry weather in June only occurs when a miticide is applied.
HIPPOs Bring in the Good Guys
Populations of some important predators, for example, the mite-eating ladybeetle (Stethorus spp.) reached levels of abundance we had not previously encountered in hops. Up to 100 Stethorus per sticky trap per week were recorded in August, about 4 to 5 times more than previous maximum levels. The abundance of other groups of natural enemies (e.g., lacewings, ladybeetles, pirate bugs, parasitic wasps, predatory mirids) was also greater in the methyl salicylate-treated hop yard than in the unbaited yard.
HIPPOs Work in Grapes, Too
In the replicated experiment in grapes, we monitored for both pests and beneficial insects using sticky traps. While the numbers of lacewings, mite-eating ladybeetles, bigeyed bugs, pirate bugs, and hover flies were not very high overall, they were more prevalent in the treated blocks (Figure 3).
Analysis of the data revealed statistically significant differences in abundance of certain natural enemy groups in both the hop and the grape sites when comparing the methyl salicylate-baited and the unbaited blocks. While not unequivocal, these limited results are very suggestive of the possibilities of using methyl salicylate dispensers to increase recruitment and maintenance of natural enemy populations in hops and grapes. Clearly, more field studies on HIPPOs are needed, and we plan to greatly expand our research in this exciting new area over the next few years.
In 2003 we also began field-testing 16 other HIPPOs; we plan to increase that number in 2004. If we can show unequivocally that HIPPOs can be used to enhance conservation biological control in hops and grapes, it will open up possibilities for other crop systems throughout the United States as well as internationally. It’s a jungle out there, but HIPPOs may help growers take a huge bite out of their pest management problems.
David James and Tanya Price are Entomologists at the Irrigated Agricultural Research and Extension Center in Prosser. They can be reached at firstname.lastname@example.org or (509) 786-9280.
Hunter, M. D. 2002. A breath of fresh air: Beyond laboratory studies of plant volatile-natural enemy interactions. Agricultural and Forest Entomology 4, 81-86.
James, D. G. 2003a. Field evaluation of herbivore-induced plant volatiles as attractants for beneficial insects: Methyl salicylate and the green lacewing, Chrysopa nigricornis. Journal of Chemical Ecology 29, 1601-1609.
James, D. G. 2003b. Synthetic herbivore-induced plant volatiles as attractants for beneficial insects. Environmental Entomology 32 (5), 977-982.
James, D. G. 2002. Natural enemies: A new weapon in the war against hop pests. Agrichemical and Environmental News 194, June. http://aenews.wsu.edu/June02AENews/June02AENews.htm#HopPests
James, D. G. 2001. Pesticide safety and beneficial arthropods. Agrichemical and Environmental News 188, December. http://aenews.wsu.edu/Dec01AENews/Dec01AENews.htm#anchor432738
James, D. G. 2000. Protecting our insect and mite friends. Agrichemical and Environmental News 168, April. http://www.aenews.wsu.edu/April00AENews/Apr00AENews.htm#anchor5232326
James, D. G. and J. Coyle. 2001. Which pesticides are safe to beneficial insects and mites? Agrichemical and Environmental News 178, February. http://aenews.wsu.edu/Feb01AENews/Feb01AENews.htm#anchor550320
James, D. G. and T. S. Price. 2002. Aromatherapy for lacewings: Using plant-produced odors to attract predators and aid biological control. Agrichemical and Environmental News 199, November. http://www.aenews.wsu.edu/Nov02AENews/Nov02AENews.htm#Lacewings
James, D. G. and T. S. Price. 2000. Abamectin resistance in spider mites on hops. Agrichemical and Environmental News 170, June. http://aenews.wsu.edu/June00AENews/June00AENews.htm#anchor5232326
James, D. G. and T. S. Price. 2000. Abamectin resistance in spider mites on hops. Agrichemical and Environmental News 173, September. http://aenews.wsu.edu/June00AENews/June00AENews.htm
Prischmann, D. and D. G..James. 2002. Surviving neglect: Bugs inhabiting abandoned vineyards. Agrichemical and Environmental News 197, September. http://aenews.wsu.edu/Sept02AENews/Sept02AENews.htm#GrapevineBugs
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Pacific Northwest States Consolidate Comments to USDA/EPA Using New Program
Dr. Catherine H. Daniels, WSU Pesticide Coordinator, and Jane M. Thomas, Western Region Regulatory Information Coordinator
One of the most common complaints from Western growers about the U.S. Environmental Protection Agency (EPA) is that "those folks use models, they don't use real data." This complaint refers to EPA’s chemical reregistration work mandated in the 1996 Food Quality Protection Act (FQPA). The reason that models don’t sit well with growers is that models, by their very nature, must take “worst case situations” into account. In other words, instead of calculating the actual use rate of a pesticide on the actual number of acres upon which it is used, a model will plug in the maximum allowable pesticide use per acre for 100% of the registered uses on all the potential acres on which it could be used. That can affect whether all uses fit in a chemical's “risk cup.” If the uses don’t fit, crops get deleted from labels. Real use data provides more, well…realistic estimates of exposure. Growers believe that with real numbers there is at least a better chance that all of a chemical's uses may still fit in the risk cup.
The good news is that when EPA scientists are able to access real data regarding field usage of pesticides, they do use it. The problem is finding that data.
So, where can EPA find data? The National Agricultural Statistics Service (NASS), the largest pesticide use tracking agency, compiles data on many, but not all crops. Notably, data on many of the minor crops so important to Washington’s agricultural economy are absent. The California Pesticide Use Reporting System has application records for all pesticides applied in that state. Pest Management Strategic Plans (PMSPs) and Crop Profiles, both of which contain pesticide use information, are heavily used by EPA staff (see Washington State’s PMSPs and Crop Profiles at http://wsprs.wsu.edu/CropProfiles.html). Another way EPA obtains real data is by publishing notices in the Federal Register (http://www.epa.gov/fedrgstr/) to solicit public comment. While this last method is important in allowing public process, it usually happens nearer the end of the decision-making process and, because of that timing, comments submitted may have less impact on the actions taken.
Each of the data sources currently used by EPA is important, but sometimes there’s no substitute for a conversation with a human being. When the level of detail exceeds that provided by databases or documents, or those questions require an answer from the grower community, EPA often calls the USDA Office of Pest Management Policy (OPMP, http://www.ars.usda.gov/opmp/). In turn, OPMP staff members often call the regional Pest Management Center directors. For our area, that is the Western Region Integrated Pest Management Center (WRIPMC). One of the many roles of the WRIPMC is to facilitate and coordinate information exchange regarding pest management issues between federal agencies, universities, commodity groups, growers, and industry. The regional directors then pass the request along to appropriate contacts in states where the pesticide use pattern is thought to exist. (Contacts in Montana, for example, would not be sought for questions about pesticide use on oranges.) Each state then handles the requests in a manner that works best for them. The information collected goes back to EPA. This process was developed so that actual pesticide use practices and patterns could be given to EPA at the time they are making review decisions about specific agrichemicals.
Sounds good, doesn't it? Finally, we are able to get EPA the kind of real life data and back-and-forth-discussions needed to help make decisions. This is a point we have wanted to reach for quite awhile. Now, of course, the ball is in our court to deliver the information they are seeking within a timeframe in which they can use it.
A fair number of chemicals are under review at any one time, and many of them are registered on a large number of crops. Sometimes, even with real data, crops will have to be removed from the label in order to fit the chemical into its risk cup. The question then becomes: which ones? An example of a detailed question EPA might ask the OPMP staff in this situation is "which of the following 25 crops are absolutely critical to leave on the label and which ones can use other products?" The timeframe in which EPA needs this information is usually less than a month, sometimes even shorter, so you can see that state contacts can be kept very busy answering these questions in addition to performing their other numerous duties. Did I mention that while a simple “no, it isn't important on this crop in our state” is a sufficient answer; a simple “yes, this tool is critical on this crop” must be bolstered with data? The EPA needs to know things like the number of acres grown, a justification of why other products cannot substitute, and a general description of what will happen to the industry if the chemical can't be used on that crop anymore. Now that the states in the Pacific Northwest had the opportunity to submit real-life data we found we needed additional staff to collect it. Thus was born the idea of a regulatory information coordinator, someone to take the questions, find the people who could answer them and then put together a formal reply packet commenting on those chemical uses. Using a form of verbal shorthand, we call this position the “Comment Coordinator.”
The Making of a Comment Coordinator
State contacts from Alaska, Idaho, Washington, Montana, Oregon, and Utah have worked together for many years on pest management issues because our cropping systems and pest management needs are very similar. In 2002, contacts from several of these states, including Washington, began discussing ways to streamline this feedback process. Rather than have each state individually reply to information requests from EPA, it made more sense to have a single Comment Coordinator who would gather information from all states and send in a single comment packet. We tested our theory during 2002. An individual was selected to act as Comment Coordinator, a project was chosen, a contact list was built, and the first comment packet was generated. The project proved successful and funding was sought to make this position more permanent.
In September 2002, Washington State University (WSU) received specific funding from the Western Region Integrated Pest Management Center for a Comment Coordinator to provide USDA and EPA with information from this six-state region. Initially, the Comment Coordinator, with help from the respective state contacts, identified comment opportunities where input was likely to influence pesticide use pattern decisions relevant to the region. The intent was to be as proactive as possible in looking for opportunities to comment early in EPA's decision-making process.
Jane M. Thomas, previously known only as WSU's Pesticide Notification Network (http://www.pnn.wsu.edu) Coordinator and occasionally as the Queen Bee of Labels, assumed the responsibilities of the Comment Coordinator on September 15, 2002.
Setting Up an Infrastructure
The first task was to devise a database to hold the information that was received while making inquiries. A lot of information would be exchanged among the states, and a mechanism would be needed to store and sort it. The resulting database provides easy access to a list of all the individuals who have provided information pursuant to the requests received so far. It also serves as a storage bin for the individual bits and bobs of information collected in the process of preparing comments on a specific issue. The Comment Coordinator can query the information by crop, contact, and/or state. Not only does the database make starting on a new project a little easier but it also stores the information gathered for a project so that when it is time to prepare the final comment package, all the relevant information can be accessed and sorted in whatever manner is most convenient and appropriate to the question.
Over the first year, nine comment packages were submitted as a result of the efforts of the six state contacts and the Comment Coordinator. The requests for comment come in a variety of forms but most often are e-mailed from USDA to Rick Melnicoe, the Director of the Western Region Integrated Pest Management Center, and are then forwarded to Jane. We have since refined the process so that the Western Region Integrated Pest Management Center staff identify comment opportunities to pass along to Jane. But while the mechanism for generating the request has been fairly consistent, the types of information sought have varied widely. Basically, any action with the potential to impact agriculture in the Pacific Northwest is fair game.
The information that goes into each comment package is derived from discussions with extension and research personnel, growers, fieldmen, chemical distributors, and anyone else who might have insight on the question at hand. In each comment package prepared so far, a contact list (sorted by crop and state) has been included so that if personnel at EPA or OPMP have additional questions about the information in the response, they can contact individuals directly. If an industry organization has prepared their own comments on the subject, we make sure our information is complementary and try to include a copy of their material in our comment packet.
In the interest
of providing a public archive of this work, the requests, any supporting
documents, and the final comment packages are all posted on the Washington
State Pest Management Resource Service Web page. At http://wsprs.wsu.edu/,
in the left navigation bar, click on Pesticides, then select Comment Coordinator:
USDA/EPA Information Requests. Note that the requests and comment packages
are posted first by active ingredient, then by project.
Below is a list of the projects that have been completed to date. The projects and known outcomes are discussed in more detail below.
Methyl Parathion. In October of 2002, EPA requested information through USDA on methyl parathion use on about a dozen crops. The agency stated that they thought methyl parathion was used on these crops but that the amount was not significant and they wondered if the uses were critical niche uses that needed to be retained. In our response we requested that, of the crops cited methyl parathion use be retained on alfalfa, barley, canola, and onion. In March, as requested by EPA, Cheminova asked that we supply additional information about the agricultural practices associated with onion and potato production in the Pacific Northwest (PNW). In May 2003 EPA issued the interim reregistration eligibility document (IRED) for methyl parathion. Here EPA stated, "The following uses are eligible for reregistration: Alfalfa, barley, corn, cotton, grass forage/fodder/hay, oats, onion, pastures, rangeland, rape seed (canola), rice, rye, soybeans, sunflower, sweet corn, sweet potatoes, walnuts, wheat, white potatoes, and yams (emphasis added)."
Dimethoate. In December 2002, EPA asked for input on dimethoate. This second project was several orders of magnitude more complex because of the large number of crops and the general nature of the request. Through a massive organizational effort and scores of telephone calls, e-mails, and faxes, a response was submitted to EPA at the end of February. In July and again in September 2003, EPA asked for additional, specific information concerning dimethoate use on succulent beans and succulent peas. Secondary and tertiary comment packages were prepared and returned to EPA. As of this writing, the only formal action that EPA has taken on dimethoate is the use cancellation announced in the September 10 Federal Register. In this notice, EPA announced the following:
In their original request for information, EPA had already indicated that apple, grape, and head lettuce uses would be deleted and that succulent beans, succulent peas, and spinach were in jeopardy. Of the other listed crops, the PNW had requested that dimethoate use on spinach seed be retained. (At the time of this writing a note has been sent to EPA's Pat Dobak, dimethoate Chemical Review Manager, asking for clarification on EPA's position regarding the use of dimethoate on nonfood/nonfeed seed crops.) It is important to note that they have not, as yet, taken action to delete the succulent bean and succulent pea uses. This may indicate that our efforts are having some impact on the reregistration process for dimethoate.
Vinclozolin. This project was far different from those on the two previously mentioned chemicals. Dr. Bob McReynolds of Oregon State University, who had been very helpful with pesticide use information for vegetable crops grown in Oregon for the previous two comment packages, contacted the Comment Coordinator in April 2003. He requested that the region prepare a letter of support for a tolerance extension for vinclozolin on succulent beans in response to a notice in the March 26 Federal Register. The use of vinclozolin is important to the Oregon succulent bean industry and this was a pro-active step to write a letter of support. A comment letter was submitted to the docket and in the September 30 Federal Register, EPA announced that the tolerance had been extended for two years and will expire 9/30/05. While several other letters of support were submitted as well, we like to think the PNW comment package favorably impacted the results.
Carbaryl. As with the initial dimethoate project, an April request regarding carbaryl was complex and preparing a response proved difficult. The list of crops involved was extensive and, to further complicate matters, the timeline was short. In preparation for finalizing the carbaryl IRED, EPA was trying to ascertain which uses were critical and whether growers could tolerate newly proposed re-entry intervals (REIs). There was some initial confusion between groups about what the proposed mitigation measures were, which resulted in Jane having to cover some ground twice in gathering information.
By the end of May we were able to provide some information regarding uses in our region that were considered important. In June EPA issued the carbaryl IRED. The results were a mixed bag, with some crops ending up with lower REIs than originally proposed (caneberries, cranberries, sugarbeets), some with slightly higher REIs (beans, peas, root crop brassica, cucurbits, filberts), and some, like sod, that were complete surprises. (In the IRED, EPA established the REI for sod farms as 12 hours for all activities except harvesting, where the REI is now 9 days.)
DCPA. In late July we received a request from USDA to gather information on sites where the herbicide DCPA was being used. EPA had contacted USDA to ask if there would be serious hardships created if the registration for this chemical were cancelled. The agency was contemplating this action because of cancer and groundwater-contamination concerns. A response was submitted late in August. As of this writing, EPA has concluded that for some of the currently registered uses, DCPA is an essential tool. Working with the registrant, EPA is now attempting to iron out carcinogenicity and toxicity issues.
The "List of 54." This project, as the name implies, covered a large number of pesticides. This project had the tightest timeline but luckily we were asked just to respond with information from Washington State. Other contacts were requested to produce California and Oregon-specific information. The request was received on Friday, August 29, 2003 from USDA's Burleson Smith and returned September 5, 2003. In his e-mail he asked that we let him know if there were any crops now in the ground that would need an application or applications of any of 54 chemicals listed before the crop was harvested. (The information request had to do with a lawsuit filed by a consortium of the Washington Toxics Coalition, Northwest Alternatives to Pesticides, Pacific Coast Federation of Fishermens, and Institute of Fisheries Resources against EPA. The lawsuit charged that EPA had failed to consult with other agencies under the Endangered Species Act (ESA) and that buffers were required on 54 chemicals until consultation takes place. (See “Salmon-Stimulated Lawsuits: Swimming in Circles or Shouldered on Sound Science?” AENews Issue No. 202, February 2003). The judge hearing the case was attempting to determine the impact to existing crops were he to immediately impose mandatory buffer zones to protect streams carrying endangered fish species. It may have become clear to the reader by this point why the project workload required dedicated staff, this isn't a request for 54 crops, which in itself is not a trivial thing; it is a request for all ag uses for 54 chemicals. Jane accomplished this information collection by sending a notification via the Pesticide Notification Network requesting input. Resulting information was summarized and submitted. To date, the court has not issued a final ruling.
Having an Impact
After a little over a year, it’s safe to say that the Comment Coordinator concept has been a success. Growers, registrants, and, most importantly, the agencies responsible for making pesticide reregistration decisions are finding the comment packages very useful.
In September 2003 the Comment Coordinator position officially became a part of the Western Region Integrated Pest Management Center. Jane continues to work at WSU Tri-Cities, still manages the PNN, and will continue to provide information from the six-state area to USDA and EPA in 2004 as the Comment Coordinator. The program’s success is underscored by the fact that similar programs are being considered in other parts of the West and in other regions of the United States.
Jane M. Thomas is Comment Coordinator and Pesticide Notification Network coordinator. Her office is on the Tri-Cities campus of Washington State University. She can be reached at (509) 372-7493 or email@example.com. Catherine Daniels is Pesticide Coordinator for Washington State University. Her office is at the Puyallup Research and Extension Center. She can be reached at (253) 445-4611 or firstname.lastname@example.org.
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New Crop for New Markets
Dr. Carol Miles, Madhu Sonde, Martin Nicholson, and Sean-Paul Cunningham, Vancouver Research and Extension Unit, WSU
Watermelon (Citrullus lanatus) seeds and leaves have been found in tombs in Egypt dating back thousands of years. In 1850, explorer David Livingston found wild watermelons in the Kalahari Desert. Based on these findings watermelon is believed to originate in Africa. Watermelons made their way to America with traders four hundred years ago, and the first written record of their cultivation in this country was in Massachusetts in 1629. Today, the United States ranks fourth in the world in watermelon production and in 2002 produced 1.86 million tons of watermelon on 15 million acres, and the crop value was $329 million. The primary watermelon producing states are Texas (26%), Florida (16%) and Georgia (14%). Consumption of watermelon in the United States totaled 3.9 billion pounds in 2000, average per capita consumption was 15.1 pounds, and Asian and Hispanic consumers were the strongest consumer groups. Watermelon is consumed as plain fruit, dessert, fruit salad, snack, picnic food, plate garnish, and as a fruit drink.
Watermelons are classified into groups according to fruit shape, rind color or pattern, and weight. These groups are often named after a popular variety with those characteristics (Table 1). Until two decades ago, watermelon was only a seasonal fruit, but today imports combined with local production ensure a year-round supply. With a rise in interest in local production and direct marketing, farmers in Washington are looking to diversify crop varieties to meet these demands. Miniature watermelons, commonly referred to as icebox watermelons, weigh from 6 to 12 pounds and offer farmers in western Washington a means of producing high quality watermelons locally. Mini watermelons were introduced to the U.S. marketplace only a few years ago from Asia, and several varieties have very recently been developed and released in the United States. Mini watermelons are rapidly gaining popularity, as their smaller size is ideal for small families and for storage in home refrigerators.
Mini Watermelon Study
In 2002, we planted three mini watermelon varieties to test their production potential at the Washington State University (WSU) Vancouver Research and Extension Unit. Based on the success of that study we planted an expanded (non-replicated) observation study in 2003 that included nine varieties. The study was conducted on certified organic land and was managed accordingly. The primary objectives of this study were to:
This report focuses on the development of mini watermelons as a new alternative crop for our region, emphasizing the results from objectives 1 and 3, above. While our mini watermelons were grown under drip and overhead sprinkler irrigation systems, a malfunction of the drip irrigation system (explained below) rendered a comparison of the two irrigation systems unfeasible. We were, however, able to measure melon yields and sizes and to conduct a consumer survey.
Mini watermelons are still new to the marketplace. They are grown by only a handful of growers in the Pacific Northwest and seed for the crop is only now becoming readily available in the United States. Studies are needed to determine maturity dates, total yield, and size and weight of melons grown in the region. Some of the varieties grown in this study are new to the United States and growers may need to specially request seed.
Mini watermelons were planted in our Vancouver greenhouse on March 24 and transplanted into the field on June 2. Transplanting was delayed due to wet field conditions in May. Other studies have shown that ideally melons should be transplanted two to three weeks after seeding. Plots were one row wide and 15 feet long and spacing between plants was 3 feet. Five plants of each variety were evaluated under both drip irrigation and overhead irrigation systems. Soil in the rows was covered with black plastic and drip tape was laid under the plastic. In the overhead irrigation system, plants were irrigated once a week at the rate of 1 inch per week from June through August. In the drip irrigation system, plants were scheduled to be irrigated twice a week at the rate of 1 inch per week from June through August. However, the drip system malfunctioned for the first two weeks; plants were extremely stressed and took weeks to recover. In some cases, the stressed plants did not recover. As a result, harvest was delayed in the drip system rows and, in many cases, yield was depressed. Thus in this report we will only present yield data for the overhead irrigation system as we feel this more closely reflects potential yield of the varieties.
Mini watermelons were test-marketed through Joe’s Place, a farm store in Vancouver. Customers were asked to fill out and return a market questionnaire. All customers paid full price for each mini watermelon they purchased and those customers who returned a completed questionnaire received a $2 coupon for their next purchase at the farm store. Through this market survey, 280 mini watermelons were purchased and 56 questionnaires were returned.
A photo of each mini watermelon was displayed and each watermelon was labeled so that customers could understand the characteristics of the variety they purchased (Figure 3, above). Mini watermelons were priced at the market price in nearby metropolitan Portland (59¢ per pound); each mini watermelon cost on average $1.80 or approximately half the cost of a regular (full-sized) watermelon. Customers were asked to rate on a scale of 1 to 5 (1=Not important and 5=Very important) whether size, color, price, organic production, and novelty played an important part in their decision to purchase mini watermelons. Customers indicated on average that novelty and color were not important in their purchasing decision while price, organic production, and size were more important (Table 3).
Customers were also asked to rate on a scale of 1 to 5 (1=Very poor and 5=Excellent) the flavor, texture, juiciness, and overall eating quality of the mini watermelons. Customers indicated that on average all eating quality aspects of the mini watermelons were very good, however some varieties were rated higher than others (Table 4). Red Delicious, Dark Belle, Smile, and Fun Belle were rated the highest in this study while Sugar Baby and Orchid Sweet were rated the lowest. All customers indicated that the mini watermelons they purchased were either very easy or easy to store in their refrigerator. Also 60% of surveyed customers indicated they would purchase the same variety again. All customers who purchased Red Delicious and 86% of customers who purchased Fun Belle indicated they would purchase these varieties again, while 75% of customers indicated they would not purchase Orchid Sweet or Sugar Baby again.