In cooperation with the Missouri State Horticulture Society
Summer 2004

2004 apple & peach crop

Coming - Columnar/upright peach trees

Latex paint protects fruit buds

In 2004, bud break of Navaho and Apache blackberries was delayed by eight days. On April 5, 2004, Redhaven peach buds treated with latex paint were at a mean bud stage of 3.6 (between calyx red and first pink) whereas untreated control buds were at stage 6 (full bloom.) Using a standard chart that lists the temperatures at which 90% bud kill occurs, the treated buds would be killed at 14 degrees F whereas untreated buds would show similar loss at 24 degrees. Treatments did not modify bud temperatures during the periods of data collection but provided a means to delay bud break. Moreover, latex paint provided considerable protection against low-temperature injury when applied during the dormant season.

Low-carb fruits for dieters

The low carb phenomenon has also affected the fruit industry as consumers want to know which fruits are considered low carb. Here is a comparison of carbohydrate levels for one-cup servings of raw fruits:

strawberry	10.7 g
raspberry	14.2 g
blackberry	18.4 g
blueberry	20.5 g
grapes, vinifera types (Thompson seedless)	28.4 g
grapes, American, slipskin types (Concord)	15.8 g
apples, with peel	19.1 g
apples, without peel	16.3 g

Ron Stephenson reported recently that a customer inquired about low-carbohydrate cider. In response to this inquiry, Penny Perkins-Veazie, USDA scientist was contacted. She commented that the watermelon producers are also battling the low carb trend. She noted that in apples and watermelon, the carbohydrates are from the sugars contained in the fruit, so using low-sugar apples would help reduce the carbohydrate levels in cider. Dr. Perkins-Veazie also suggested that sucralose (Splenda®) could be added to the cider to increase the sweetness. However, she cautioned that the artificial sweetener should be tested to make sure that browning doesn't occur. Another alternative would be to dilute the cider with water, but again the cider taste would be lacking. Another problem would be that the diluted cider is no longer a 100% fruit juice but rather a juice drink with the added water.

The low-carbohydrate diet was popularized by the Atkins diet. This diet has been criticized by nutritionists, but recent evidence indicates that it can reduce weight without the feeling of food deprivation. This diet, along with the South Beach and Paleolithic diets, is effective because it decreases insulin levels and thereby prevents storage of fats. A Harvard study indicates that mice fed diets with the same calories, differing only in the amount of carbohydrates, showed increased fat deposits with high carbohydrates. However, these diets can be deficient in other aspects of nutrition.

The January 2004 issue of Stagnito's NewProducts Magazine reported that 3.6% of Americans are on low-carb diets, up more than 33% from six months earlier. More important, 40% of Americans identified carbs as a "dietary no-no" as compared with 11% in the previous year. The food industry has responded with new low-carb products worth a billion dollars in sales.

It is predicted that the low-carb trend will persist longer than the low-fat boom that occurred a decade ago because these Atkins types of diets work. However, when people go off the low-carb diets, they quickly gain the weight back. Experts agree that the healthy solution to obesity is a sensible diet, smaller portions, and reduced intake of highly refined starches and sugars, combined with increased exercise. Nutritionists will likely continue to advocate fruits and vegetables as a part of the food pyramid and important components of a healthy diet.

Paintball, anyone?

Honeycrisp problems & solutions

The most notable problem with Honeycrisp is that more than 50% of the fruit harvested from young plantings develops bitter pit before harvest or during storage. While bitter pit is common in young, lightly cropped apple trees, this physiological disorder is still problematic in Honeycrisp trees after 4 or 5 years of regular cropping. Typically applying calcium in foliar sprays during summer reduces bitter pit. However, results with calcium applications on Honeycrisp have been variable. Calcium sprays can also be phytotoxic to apple foliage when applied at high concentrations and high temperatures. In some earlier studies, trifloxystrobin (Flint® fungicide) reduced the incidence of bitter pit in Idared, Stayman and Delicious fruit when applied in eight cover sprays in New York. Harpin protein (Messenger®) has also been marketed as a product to enhance growth, fruit development and nutrient uptake in various plants.

Recently Cornell University researchers conducted experiments to minimize Honeycrisp fruit losses due to bitter pit. They applied calcium chloride (CorClear®), trifloxystrobin, sodium borate (Solubor®), or harpin protein alone or in various combinations. Based on the results of this study, calcium chloride was the only compound that consistently reduced bitter pit. Researchers recommend at least six applications of calcium chloride per season with a seasonal total of at least 3 lb/acre of elemental calcium on Honeycrisp trees that can be sprayed to drip with 100 gallons/acre of spray solution. For larger trees that require more than 100 gallons/acre for complete coverage with a dilute spray, calcium application rates may need to be increased proportionately.

Avoiding drift with buffers

While this ruling is controversial because chemical compounds differ in their toxicological and biochemical properties, growers everywhere have a responsibility to avoid spray drift and keep pesticides on targeted areas. Best management practices to minimize drift include the following:

1. Adjust or replace sprayer nozzles to produce coarser droplets. Small droplets drift greater distances before hitting the ground.
2. Spray when the wind speed is less than 10 mph. Also do not apply pesticides during an inversion when spray droplets move horizontally. Inversions can occur in the early morning and in the afternoon.
3. Consider spraying alternate rows.
4. Plant a barrier row(s) of pine trees, especially if spraying near residential areas.

In Missouri, the most reliable native tree to plant in a barrier row is shortleaf pine. Shortleaf pine (Pinus echinata) trees are available from the Department of Conservation State Nursery at Licking. Scotch pine should be avoided because of its susceptibility to nematodes. White pine is subject to environmental stresses and performs poorly on droughty or wet soils. University of Missouri horticulturist Chris Starbuck is evaluating selections of hardy loblolly pine and hybrids of pitch and loblolly pine for adaptability in Missouri at the Horticulture and Agroforestry Research Center in New Franklin. He believes that these types of pines may be promising in providing a barrier to drift and in producing a profitable crop of pine straw that is sold as a landscape mulch. If you are interested in trying some hybrid pitch and loblolly pine trees contact Dr. Starbuck at starbuckc@missouri.edu or 573-882-9630.

Blue replaces red wines

At Chester Hill winery, berries are lightly crushed and fermented with red wine yeast. The New Blue wine is made in a nouveau style to accentuate the fruitiness of the wine. For this wine, fruit is picked in July, bottled in October, and marketed for the November and December holidays. New Blue is promoted as a wine that accompanies roast turkey - "An American wine for an American tradition...Thanksgiving!" It is also paired with spicy foods (Mexican, Chinese, Indian and Thai), tomato sauces, grilled dishes and poultry.

Another of the Chester Hill products, their Best Blue wine, is aged in American Oak barrels for three to four months. This dry wine (1% residual sugar) is ready for sale the summer after the fruit is harvested. With its "hints of vanilla and toasted caramel," Sullivan suggests that Best Blue is good with cheeses such as Roquefort or cheddar, red meats, salmon, stews and game. It can also be enjoyed with chocolates.

The third blueberry product is Bay Blue, which is a port-style wine. It is a mixture of one- or two-year-old blueberry wine infused with grape brandy that has been aged in oak (6% residual sugar and 18% alcohol by volume). Bay Blue is marketed as an aperitif or with chocolate desserts, cheesecake or vanilla ice cream.

At the winery, they have wine tastings and sell themed products such as blueberry or grape motif bottle bags and cocktail napkins, cobalt blue bottle stoppers, rapid ice bottle chillers, blueberry-scented candles, blueberry tea, chocolate covered blueberries and wine motif silk ties. Chester Hill Winery also participates in wine and blueberry festivals and wine competitions. They have been featured with Bobby Flay on Food Network and in several travel guides.

Mites, mites and more mites!

A common spider mite in Missouri apple orchards is the European red mite (ERM). Depending on the locality and length of the growing season, there can be 4 to 9 generations of ERM a year. The rate of ERM development is temperature dependent - slower in the spring and fall and more rapid during the hot summer months. The first generation generally requires about three weeks to develop, while summer generations may develop in 10 to 14 days.

Injury is caused by the feeding activity of the immature and adult stages on the foliage. The lower leaf surface is preferred, but under high populations both surfaces are fed upon. The injury results in off-color foliage, which in severe cases becomes bronzed. Heavy mite feeding early in the season (late June and early July) not only can reduce tree growth and yield but also drastically affect fruit bud formation, and thereby reduce yields the following year. Additionally, mite-injured leaves will not respond to growth regulators applied to delay harvest drop.

Mite predators are common in commercial apple plantings and should be protected. But mite populations can also be controlled by thorough and timely acaricide applications. The most effective treatments are those applied after new growth has appeared but before bloom. Seasonal control can often be obtained with a single petroleum oil spray directed against the overwintering eggs or application of an acaricide toxic to the newly hatched forms. Against established populations in the summer, it is often necessary to make two applications 10 to14 days apart. Consult the 2004 Commercial Tree Fruit Spray Guide for a list of recommended miticides.