07/26/1996

Fruit, Vegetable Growers Attend Cullman Field Day

CULLMAN - Home gardeners and commercial growers from the Cullman area saw the latest in fruit and vegetable research technology and visited with scientists from Auburn University during a recent field day held at the North Alabama Horticulture Substation here.

The 159-acre Alabama Agricultural Experiment Station research facility is nationally recognized for sweet potato and other vegetable research. The annual Fruit and Vegetable Field Day drew about 100 people and featured tours of research plots and explanations of the research by scientists from Auburn University.

Extension Ag Engineer Larry Curtis demonstrated the use of a micro irrigation system used at the Substation to irrigate vegetable crops. Micro systems, unlike overhead irrigation systems, wet only the soil, reducing the likelihood of some plant diseases that thrive on wet foliage. The micro system, Curtis noted, also allows growers to better regulate fertility, since fertilizers can be injected into the irrigation system and applied directly to the plant in precise amounts. The micro system also works off very low pressure, reducing both cost and maintenance. More information about micro-irrigation systems is available from County Extension offices.

Several visitors to a pear research orchard noted that some of the trees looked familiar. "They should," said Auburn researcher Billy Dozier, "because the trees are seedlings from domestic pear trees that have grown in various spots around the state---some of the parent trees are more than 100 years old." Dozier and other Auburn researchers are looking at dozens of old varieties to determine how they will perform under different growing conditions.

Dozier and Interim Substation Superintendent Arnold Caylor also showed the crowd a trellised apple orchard fertilized primarily with yard waste from the Decatur Landfill. "We found that mature apple trees need less nitrogen than most commercial growers use, and we found that by putting a two-inch deep, six-foot wide layer of this yard waste mulch around the trees, the trees were getting plenty of nitrogen," Dozier said. He pointed out that the mulched trees in the test were larger or fuller than those grown with no nitrogen or with varying rates of commercial nitrogen.

Commercial vegetable growers were encouraged by results obtained by Auburn researcher Geoff Zehnder using a combination of new insecticide (Javelin) and low rates of synthetic pyrethroids to control corn earworms in sweet corn.

"For home gardeners, the solution is simple: you just cut off the damaged end of the ear. For commercial producers that isn't an option," Zehnder explained.

Using two ounces of a synthetic pyrethroid combined with Javelin, Auburn researchers were able to reduce the number of sprays per season and still control corn earworms. "The low rates of pyrethroids helped control earworms, but didn't totally take out beneficial insects, especially parasitic wasps that feed on earwoms. We used three-fourths of a pound of Javelin in combination with the pyrethroids, and the combination worked really well," Zehnder concluded.

Recent changes in the Soviet Union have caused some unexpected impact on Sand Mountain area farmers. The supply of anhydrous ammonia for nitrogen fertilizers has been erratic and the cost higher. The result is that many growers are seeking other sources of nitrogen fertilizer. In some crops, such as watermelons, there are questions about which sources of N are viable. AU Agronomist Beth Guertal has been exploring the uses of other forms of N on vegetable crops.

Guertal tested compared the performance of watermelons grown with commercial ammonium nitrate, calcium nitrate, potassium nitrate and urea as sources of N. Preliminary results show little difference in melon performance among the various fertilizers. "We have only one year of data and no quality data, so we have to be careful in making bold statements, but we didn't see any major differences among the various nitrogen sources. We even added gypsum to provide extra calcium, but that didn't show much difference either," Guertal added.

Field day attendees also saw the first year of a low input vegetable project being conducted by Auburn researcher Ed Sikora. Sikora is a plant pathologist who was instrumental in helping Sand Mountain area growers identify a virus that ravaged that area's tomato crop a few years ago. Those interested in the progress of this first year of the test are encouraged to stop by the North Alabama Horticulture Substation and take a look.

"We had a good mix of home gardeners and commercial producers at the field day and we tried to provide some information to help both groups," noted Caylor. "Field days are important because they allow people to see what we are doing and perhaps more importantly, they provide us with a chance to learn what growers need, which helps us plan future research projects," Caylor concluded.

SIDEBAR: WHAT COLOR PEPPER IS HOT?

CULLMAN - During a recent Fruit and Vegetable Field Day at the North Alabama Horticulture Substation in Cullman, Auburn University researcher Eric Simonne was asked some interesting questions about peppers. His answers caught some growers by surprise.

For example, visitors asked: Why are red peppers hotter than green or yellow peppers?

"There is no relationship between color of peppers and hotness of peppers," Simonne replied. He explained that color and taste are controlled by different genes and that it is entirely possible to get a yellow pepper that is hotter than red or green, or vice-versa.

Another question asked by visitors was: Will hot and mild peppers cross-pollinate and, if so, will hot peppers become milder and mild peppers become hotter?

"They will cross pollinate, but that will not affect whether the pepper is hot or mild. Some growing conditions and soil characteristics may slightly alter the degree of hotness or mildness, but the source of pollination will not affect it," Simonne said.

Simonne, a native of France, joined the Auburn faculty three years ago to work with the Alabama Agricultural Experiment Station's vegetable variety trial research program. He has been evaluating the performance of traditional vegetable varieties and also testing new vegetable crop ideas, such as new colored varieties of squash, egg plant and peppers.

The varieties trials have shown that these novelty varieties have potential for production in the Southeast. Howeverm Simonne cautioned that field day visitors that "Color makes a difference in appearance and marketability, but it is a very unreliable way to judge how any of these vegetables will taste."monne informed the crowd.

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News from:

Office of Ag Communications & Marketing

Auburn University College of Agriculture
Alabama Agricultural Experiment Station
3 Comer Hall, Auburn University
Auburn, AL 36849
334-844-4877 (PHONE) 334-844-5892 (FAX)

Contact Jamie Creamer, 334-844-2783 or jcreamer@auburn.edu
by Roy Roberson

07/26/96