Facts for Fancy Fruit 2000-10 July 12, 2000

Crop Conditions:  Peach harvest is underway, with Redhaven harvest
beginning in the southern half of the state.  Although the frequent
rain may have caused problems with disease control, there are some
excellent looking crops.  Apples continue to size well.  Many growers
have some fireblight, but the worst should be over by now.  Certainly
we have not seen fireblight at crisis proportions as the folks in
Michigan have.  Blueberry harvest continues and size and quality are
excellent.  Fall-bearing red raspberries are beginning to ripen.  Early
grape varieties should start ripening over the next couple of weeks in
southern Indiana.

Special Notice: This will be the last newsletter issued on a bi-weekly
basis. The rest of the issues for 2000 will be published on a monthly
basis August through November.

Apple Fruit Rot Alert: An ÔalertÕ in any business means to have
heightened awareness of a specific ÔsituationÕÉthe specific situation
we have in mind is the combination of wet weather and the fungi that
cause fruit rot, a deadly combination. Wet weather is ideal for fungal
diseases such as sooty blotch and flyspeck, black rot, bot rot, bitter
rot and any other rots that might have made their way into your
orchard. If wet conditions do persist the most critical thing you can
do is to maintain a tight spray schedule; see  ID- 168, Ò2000 Indiana
Commercial Tree Fruit Spray Guide Ò, for suggested fungicides.  As
always, good orchard sanitation is a must for control of summer rot
disease problems.  Remove and destroy all dead and/or dying wood from
your orchardÉNOW; this means brush piles, old prunings on the orchard
floor, dead trees, dead limbs in trees, etc.  -Pecknold

Brown Rot Warning Continues:   As peach harvest continues, be aware of
the need for sprays to control brown rot.  Warm, wet, humid weather is
particularly favorable for brown rot.  Pre-harvest sprays for brown rot
should be started no later than 3 weeks before harvest or when fruit
begins to color.  Elite, Indar and Orbit are relatively new sterol
inhibitor fungicides that give excellent control of brown rot.  For
further information on fungicides and timing of spray applications see
ID-168, Ò2000 Indiana Commercial Tree Fruit Spray Guide Ò.  In addition
to maintaining sprays for brown rot, also maintain sprays for insect
pests that may injure fruit and allow brown rot to gain a foothold.
Use care in the picking and handling of fruit to avoid punctures and
skin abrasions.  Any break in the skin of the fruit enables brown rot
to more easily cause infection. -Pecknold

Necrotic Leaf Blotch On Goldens: Generally we first start noticing
necrotic leaf blotch (NLB) on Golden Delicious in late June or July,
when the weather becomes hot and sticky.  Symptoms of NLB are leaf
yellowing and drop; often patches of brown blotches develop along with
leaf yellowing.  Symptoms develop suddenly, almost overnight, and in
waves, generally from June through August.  The cause of NLB is not
known; however, the disorder is thought to be related to air
temperature, light intensity and soil moisture.  It is most severe when
a cool, rainy period of 4 - 5 days precedes several hot, sunny days.
Although it appears NLB is not fungal caused, the disease is reduced
when ziram is included in the cover sprays. -Pecknold

Botrytis Bunch Rot:   Many grape varieties are now at or approaching
Ôbunch closingÕ, a stage when berries within the cluster begin to
touch. This is an important time to apply a fungicide to protect
against Botrytis bunch rot since it is the last opportunity to get
coverage in the interior of the berry cluster. Botrytis is particularly
severe on tight-clustered French hybrids, such as Vignoles and Seyval,
and most vinifera varieties, especially Pinot noir, Riesling, and
Chardonnay. Proper timing and thorough spray coverage are essential for
good control. Direct the spray toward the fruit zone, and use a minimum
of 100 gal/A of water.  Removal of leaves around clusters before bunch
closing has been shown to reduce losses caused by Botrytis.

Timing:  There are four application times: 1. early to mid bloom;  2.
just prior to bunch closing;  3. veraison (beginning of fruit
ripening);  4. prior to harvest if needed. Do not make more than 4
applications of these materials per season.

Materials:  Three products are registered for control of Botrytis.  It
is important to realize that these fungicides are effective ONLY
against Botrytis. They provide no protection against black rot, bitter
rot, the mildews, etc. It is also important to remember that these
fungicides are prone to resistance development in the pathogen
population, so they should be used carefully.

Rovral 50 WP is registered for use at the rate of 1.5 to 2 lb./A.
Include a spreader-sticker, especially at the 1.5 lb. rate. Do not
apply within 7 days of harvest.

Vangard 75 WG is registered for use at 10 oz./A when used alone, or at
5 to 10 oz./A when used in a tank mix.  No more than 20 oz. of Vangard
can be applied per acre per season and it cannot be applied within 7
days of harvest. Vangard is a system fungicide that resists wash-off
and has shown limited (48 hr) post infection activity against other
diseases on other crops. It is classified as a Ôreduced riskÕ fungicide
by EPA due to its favorable environmental and toxicological properties.

Elevate 50 WG may be applied at 1 lb. per acre.  No more than 3 lbs. of
Elevate may be applied per acre per season.  Elevate can be applied up
to and including the day of harvest (0 day PHI).

NOTE: Growers in Europe and Canada have experienced loss of disease
control due to the development of fungicide resistance when more than 3
sprays/year of Rovral were applied over a period of 3-5 years.  Vangard
and Elevate are also at risk for fungicide resistance development.  It
is therefore strongly recommended that Rovral, Elevate, and Vangard use
be limited to a maximum of 3 applications per year to reduce the
probability of developing strains of Botrytis that are resistant to
these materials. In addition, growers should consider alternating
applications of Rovral, Elevate, and Vangard during the growing season.
-Bordelon

Grape Bitter Rot:  Bitter rot is a common problem in southern Indiana,
especially during wet years. Unlike black rot which does not infect
berries once they are past 5-8% sugar content (veraison), bitter rot
attacks only mature berries. Both diseases result in black, shriveled
(mummified) fruit, and some growers mistake bitter rot for black rot. A
Òrule of thumbÓ is that if a rot resembling black rot develops on
mature berries (8% sugar or above), the cause is probably not black
rot. This late season rot is likely to be bitter rot. The new systemic
fungicides (Nova, Bayleton, and Rubigan) are NOT effective against
bitter rot. If bitter rot is a problem, pre-harvest applications of
Captan may be beneficial. However, infection likely starts at or near
bloom, so good coverage in the pre-bloom and 1st postbloom spray is
critical.  Observe all pre-harvest restrictions.  -Bordelon

Tissue Analysis Grapes and Small Fruits:  Plant nutritional status is
important for all phases of plant growth and has a direct effect on
vigor, fruitfulness, cold hardiness, and other factors. Tissue analysis
is the most reliable means of determining plant nutritional status.
Combined with soil testing, tissue analysis can help pinpoint the
source of problems and determine what measures may be needed to ensure
proper nutrition of the crop. Tissue analysis samples should be
collected at the appropriate time to give the most meaningful results.
For strawberry, sample the first fully expanded leaves after
renovation, usually in mid to late July. For brambles, sample leaves on
non-fruiting canes (primocanes) between August 1 and 20. For
blueberries sample leaves during the first week of harvest. For grapes,
samples should be taken about 70 days after full bloom, usually early
to mid August.  Samples should be adequate in size. Collect 30-60
leaves for strawberries, brambles, and blueberries, and 100 leaf
petioles for grapes (for grapes submit only the leaf petiole, or stem,
for analysis, discard the leaf). Collect samples to represent the
entire field, not just from a few plants. Sample different cultivars
separately. If specific problems exist, collect separate samples from
both normal and problematic areas of the planting.
	There are several private companies and a few universities that
provide tissue analysis. Your county extension office has a list of the
ACP Certified plant and soil analysis labs in Indiana. The Midwest
Small Fruit Pest Management Handbook has a chapter on tissue analysis
and fertilizer recommendations. It is available for $6.00 from the
Purdue Media Distribution Center at 1-888-EXT-INFO (1-888-398-4636) or
on line at http://www.ag.ohio-state.edu/~sfgnet/ - Bordelon

European Red Mites:  I have seen a number of orchards throughout the
state that have high populations of European red mites. Growers are
advised to be checking their problem blocks weekly for the next few
weeks to detect populations before they get out of hand. If you have a
problem (more than 5 mites per leaf), you have three viable options,
Pyramite, oil, or Apollo. At this point, Pyramite would be my first
choice. It gives dependable control, bringing expanding populations
down to low level in a short period of time. The only negative is that
Pyramite appears to be fairly hard on predator mites. The summer oils
will give reasonably good control as well. With the increases in
populations that we have been seeing, I would expect that most growers
would have to make more than one application to get these mites under
control. The advantage of oil is that it is inexpensive. The
disadvantages are the possibility of needing multiple applications and,
most importantly, the incompatibility with captan. Applying summer oil
within two weeks of a captan application may cause yellowing and loss
of leaves. While this does not always happen, it occurs often enough
that I wouldnÕt want to push it. Ziram is a potential replacement
fungicide for captan that is compatible with oil. Finally, the revised
pre-harvest interval for Apollo allows it to be used as a rescue
treatment. As many of you know, I have had some concerns about how well
Apollo would work as a rescue treatment. I am still in the process of
collecting data, so the opinions expressed here are not the final word
on the subject. So far, it appears to me that if you apply Apollo
relatively early in the season when mite populations are just starting
to get going, it works quite well. Within two weeks, the populations
are pretty much down to zero. However, later in the season, when mites
are really increasing in numbers rapidly, the two weeks that it takes
for the mites to die off may not be acceptable. So, for now, I would
prefer that you apply Pyramite or oil if you have a problem at this
point in the season. Stay tuned for more information on our results for
this year. You can probably bet that this will be a topic of
conversation at the winter meetings. ÐFoster

Watch those Weeds:  With rain occurring on an almost daily basis, the
growth of weeds has been amazing this year.  Weeds can really hold back
the growth of young trees, so try to keep them as clean as possible.
At this time of the year, Roundup around young trees can be pretty
risky, so IÕd hand weed if practical or use paraquat, being careful to
avoid contact with the trunks. -Hirst

New Zealand Fruit Tour:  If you plan on joining us for the fruit tour
of New Zealand from Feb 19-Mar 4, 2001, then I suggest you register
soon.  There has been considerable interest in this tour and the
deposits have started to arrive.  Space will be limited to the first 30
that send in their money.  I believe we have put together a tour that
will be educational as well as fun. If you would like a registration
form, please call Penny White (765-494-1301), or for more details call
or email Peter Hirst (765-494-1323).

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Coming Meetings:

August 2 Ð Southwest Michigan Annual Viticulture Field Day and Steak
Cookout. Southwest Michigan Research and Extension Center, Benton
Harbor, MI. Contact Tom Zabadal 616-944- 1477.
--------------------------------------------------------------------------------------------
Bruce Bordelon, 1165 Dept. of Horticulture, Purdue University, West
Lafayette, IN 47907-1165, 317/494-1301, e-mail:
bordelon@hort.purdue.edu

Peter Hirst, 1165 Dept. of Horticulture, Purdue University, West
Lafayette, IN 47907-1165, 317/494-1323, e-mail: hirst@hort.purdue.edu

Paul Pecknold, 1155 Dept. of Botany & Plant Path., Purdue University,
West Lafayette, IN 47907-1155, 317/494-4628, e-mail:
Pecknold@btny.purdue.edu

Rick Foster, 1158 Dept. of Entomology, Purdue University, West
Lafayette, IN 47907-1158, 317/494-9572, e-mail:
Rick_Foster@entm.purdue.edu


Disclaimer:  Reference to products in this publication is not an
endorsement to the exclusion of others which may be similar.  Any
person using products listed in this newsletter assumes full
responsibility for their use in accordance with current label
directions of the manufacturer.