WATCH FOR:
By Lee Townsend

CEREAL LEAF BEETLES emerge from winter hiding, begin to feed

PINE NEEDLE SCALE crawlers active soon

FUNGICIDE GUIDE FOR PRODUCERS OF BURLEY AND DARK TOBACCO IN KENTUCKY - 2005
By Kenny Seebold

The portfolio of fungicides available to tobacco growers in Kentucky has changed from that of 2004. The crisis exemption granted for Quadris in 2004 for control of target spot and frogeye leaf spot was not renewed for 2005. Quadris is being reviewed the EPA and we have been told to expect the process to be complete by December of this year. Thus, use of Quadris in the 2005 growing season is not permitted by law. I will continue to monitor the registration progress for Quadris and will provide updates on any changes in status of this product for 2005.

The following tables contain a summary of effective, labeled chemicals that are available to growers in Kentucky for use in the production of burley and dark tobacco in 2005. Materials are available for use against blue mold and will provide reasonable control if applied in a timely manner. Keep in mind that resistance to Ridomil Gold is widespread in populations of the blue mold pathogen and that the risk for control failure can be quite high. We do not have products that will provide consistent and effective controls of diseases such as target spot, frogeye leaf spot, brown spot, and ragged leaf spot. When available, Quadris should help fill this gap. Dithane will suppress (but not control) frogeye leaf spot and, to some extent, target spot. Maximum efficacy, such as it is, will be achieved only through timely and regular applications.

As always, read all product labels carefully and follow all directions provided by the manufacturers. Each product has specific use directions that should be followed to minimize the risk of damage to the crop and to maximize the effectiveness of the product. Products such as Actigard can be useful tools for disease management but can cause serious crop injury if applied incorrectly. The following summary is provided as a general set of guidelines to aid in product selection but is not intended to replace product labels

Guide to Chemicals Available for Control of Tobacco Diseases 2005 - Transplant Production

	Product rate
Product(s)	Per application*	Per season	Target diseases	Label notes
Agricultural Streptomycin	100-200 ppm	no limit	wildfire	Outdoor beds only
Agri-Strep	(1-2 tsp/gal H2O)	blue mold	no limit	Apply in 3-5 gallons/1000 sq. ft.
Dithane DF	0.5 lb/100 gal H2O	no limit	blue mold anthracnose damping-off	Apply 3-12 gallons/1000 sq. ft. Begin when plants are larger than dime-size.
Milk			tobacco mosaic virus (plant-to-plant spread)	Apply to plants at least 24h prior to handling. Mix will treat 100 sq. yd.
Whole/Skim	5 gal/100 gal H2O	no limit
Dry	5 lb/100 gal H2O	no limit
Terramaster 35WP	1-2 oz/100 gal H2O	4 oz / 3 apps	damping-off	Apply to float-bed water no earlier than 2 weeks after seeding. Additional applications can be made at 3-week intervals. Use high rate for curative treatments; begin no sooner than 3 weeks after seeding. Do not apply later than 8 weeks after seeding.
Terramaster 4 EC	0.7-1.4 fl oz/100 gal H2O	2.8 fl oz / 3 apps.	(Pythium spp.)root rot (Pythium spp.)

*Rate range of product. In general, use higher rates when disease pressure is high. Refer to product label for application information, restrictions, and warnings.

Guide to Chemicals Available for Control of Tobacco Diseases 2005 - Soilborne Diseases

	Product rate
Product(s)	Per application*	Per season	Target diseases	Label notes
Fumigants
Chloropicrin	60-100 lb/A (broadcast)	--	black root rot black shank damping-off nematodes	Inject to 8-in. depth. Apply when soil temperatures are >55 °F and moisture levels are adequate. Apply a minimum of 3 weeks before setting transplants.
Chlor-O-Pic	150-500 lb/A (broadcast)	--
Telone C-17	10.8-17.1 gal/A (broadcast)	--	bacterial wilt black root rot black shank nematodes	Inject to 8-in. depth. Apply when soil temperatures are >55 °F and moisture levels are adequate. Apply a minimum of 3 weeks before setting transplants.
Telone C-35	13-20.5 gal/A (broadcast)	--
Non-fumigants
Ridomil Gold EC			black shank
preplant only	2-3 pt	3 pt
preplant + layby	2 pt + 1 pt
preplant + 1st cultivation + layby	1 pt + 1 pt + 1 pt
Ultra Flourish			black shank
preplant only	2-3 qt	3 qt
preplant + layby	2 qt + 1 qt
preplant + 1st cultivation + layby	1 qt + 1 qt + 1 qt

*Rate range of product. In general, use higher rates when disease pressure is high. Refer to product label for application information, restrictions, and warnings.

Guide to Chemicals Available for Control of Tobacco Diseases 2005 - Foliar Diseases (Field)

	Product rate
Chemical	Per application*	Per season	PHI** (days)	Target diseases	Label notes
Agricultural streptomycin	100-200 ppm	no limit	0	wildfire
Agristrep				blue mold
Acrobat 50WP	2-8 oz	32 oz	0	blue mold	Increase rate and app. volume as crop size increases. Acrobat must be tank-mixed with another fungicide.
Actigard 50WG	0.5 oz	1.5 oz (3 apps.)	21	blue mold	Begin applications when plants are >18 inches in height. Make up to 3 applications on a 10-day schedule. Apply in a minimum of 20 gal/A.
Dithane DF	1.5-2 lb	no limit	30	blue mold damping-off anthracnose	Apply on weekly schedule; discontinue sprays when blue mold threat no longer exists.
Ridomil Gold EC	½-1 pt	3 pt	n/a	blue mold	Apply to soil at transplanting for blue mold; make 2nd application if needed at layby.
Ultra-Flourish EC	½-1 qt	3 qt

*Rate range of product. In general, use higher rates when disease pressure is high. Refer to product label for application information, restrictions, and warnings.

**Pre-harvest interval

For the latest blue mold status and other tobacco disease information, check the KY Blue Mold Warning System online.
http://www.uky.edu/Agriculture/kpn/kyblue/kyblue.htm

RECENT OUTBREAK OF BACTERIAL SOFT ROT/BLACKLEG
By Kenny Seebold

Gary Palmer and I were called recently to look at some tobacco seedlings that were said to be in pretty bad shape. After a quick look, it was apparent that blackleg had become established in the beds and had caused some serious losses. We tend to think of blackleg as a problem when the plant canopy is full and when weather is warm; however, this outbreak occurred during the recent spate of cool, rainy weather. Moreover, the grower in question had kept a careful eye on fertility levels in his float system, knowing that excess nitrogen can favor infection by bacterial pathogens. Why did this particular grower have problems with blackleg even though reasonable steps were taken to prevent it? We'll never know for sure, but here are a few thoughts.

The bacteria that cause blackleg need a lot of moisture and, to some extent, warm temperatures to cause disease. Typically, these pathogens enter plants through wounds and by bridging from dead or senescent tissue to healthy, susceptible tissue. The latter is why it is critical to avoid excess fertilizer. Heavily fertilized plants grow rapidly and tissues tend to be "tender" and more susceptible to invasion by plant pathogens (including bacteria). Keep in mind that our grower had managed fertility well, but still had a problem with bacterial disease. What happened? It is likely that excess moisture played a role. The combination of radiant heat in the float-house and overcast, rainy weather more than likely led to long periods of leaf wetness. Infections and symptoms probably began at low levels and went unnoticed. We also know that the plants in question were aggressively clipped, creating multiple wounds that served as entry points for bacterial pathogens. A mower is a very effective, albeit unintended, tool for spreading bacterial (and fungal) pathogens. To make a long story short, it looks like a "perfect storm" of events led to the outbreak of blackleg that we are discussing today.

What could our grower have done to prevent blackleg in his transplant facility? Hindsight, as they say, is 20/20. The combination of wet, overcast weather and seedlings approaching setting-size might have been cues to be on the lookout for bacterial diseases. When symptoms first appear, streptomycin (an antibiotic) can be applied at 100-200 ppm and will suppress bacterial diseases to some degree. Keep in mind that streptomycin is labeled specifically for outdoor beds; use in greenhouses is not specifically prohibited either, but the grower assumes all liability if the antibiotic is used in a greenhouse. Streptomycin can also cause stunting and yellowing of plants, particularly at higher rates. Don't ignore cultural practices either. Keep an eye on fertility levels and avoid "pushing" plants along with extra fertilizer. Keep wounding events to a minimum. Maintain conditions that don't promote long periods of leaf wetness.

It is unfortunate that a grower such as the one in our story today can do all the right things and still have problems with transplant diseases. In the end, "doing things right" minimizes, but does not eliminate, the risk of disease development in a float system. Following recommended cultural practices can keep a grower ahead of bacterial diseases, but keep in mind that routine inspections of tobacco transplants are crucial to alert the grower of problems and allow time for control measures, such as antibiotics, to be employed and be effective.

WATCH FOR INSECT ACTIVITY IN FLOAT TRAYS
By Lee Townsend

Variegated cutworms can be one of the most destructive pests in tobacco float bed systems. The moths fly in March and can enter greenhouses and lay masses of eggs on very small plants. The first indication of activity may be small clusters of missing plants in trays near the edges of the structure. These bare spots can expand dramatically as the larvae grow.

Check cells carefully around missing plants for signs of feeding damage to the leaves. Small cutworms tend to chew rounded areas inward from the leaf margins; larger cutworms can devour entire plants. They tend to feed at night and hide under plants or in the media during the day. Catching infestations early is important because the damage potential escalates as the cutworms grow. About 75% of their feeding occurs during the last few days of development.

Cool, wet conditions are just right for many flies that can develop in float trays, including fungus gnats and shore flies. The larval stages of both occur in the moist growing medium and rarely are seen but the small adults can be very abundant in greenhouses and around float beds. The gnats do not feed on plants but can be seen crawling over the leaves. In some cases, the larval stages may damage plant roots or leaves in direct contact with the media but this usually is minor.

The main insecticide option for greenhouse / float bed application is Orthene 97 at the rate of 3 /4 teaspoon in 3 gallons of water for every 1,000 square feet of bed. It can kill cutworms as a stomach poison or gnats and flies by direct contact. Thorough coverage is important for best results.

For more information about tobacco pests, visit "Insect Management Recommendations".

MANAGING ITALIAN RYEGRASS AFTER PLANTING NO-TILL CORN
By James R. Martin

Achieving complete control of Italian ryegrass can be a challenge in no-till corn. It is not unusual to have 30% regrowth of ryegrass where a burndown treatment of Gramoxone Max plus Atrazine was applied in the spring. The fact that emergence of seedling ryegrass can extend into the spring also limits the ability to manage this problem weed.

Fields with a history of ryegrass should be monitored for regrowth from burndown treatments and for emergence of new seedlings. The following table lists postemergence herbicides registered for controlling ryegrass in corn. The maximum size listed in the table is based on growth of newly emerged seedlings. UK data suggest that optimum control of regrowth from established plants is most likely to occur when postemergence treatments are applied 3 to 5 weeks after the burndown treatment. Control may be erratic if post treatments are applied sooner than 3 weeks or later than 5 weeks after the burndown treatment. Apparently the amount of regrowth during the 3 to 5 week interval is sufficient for uptake and translocation of the postemergence herbicides, but not too much or too mature for effective control.

Table 1. POSTEMERGENCE HERBICIDES REGISTERED FOR RYEGRASS CONTROL IN CORN
HERBICIDE	RATE	RYEGRASS MAXIMUM HEIGHT	HERBICIDE	RATE	RYEGRASS MAXIMUM HEIGHT
Accent	0.67 oz/A	6 "	Equip	1.5 oz/A	4"
Basis Gold	14 oz/A	4"	Lightning Clearfield Corn	1.28 oz/A	1-6"
Beacon	0.76 oz/A	1-4"	NorthStar	5 oz/A	1-4"
Celebrity Plus	4.7 oz/A	2-6"	Option	1.5 oz/A	8"
Clarion	0.5 oz/A	4"	Steadfast	0.75 oz/A	4"
Glyphosate (3 lb ae/gal) *RR Corn	2 pt/A	6"	Steadfast ATZ	14 oz/A	4"

* Several glyphosate products are available. Consult label for specific rate.

For information about corn pests, visit "Insect Management Recommendations".

WHEAT FUNGICIDE UPDATE
By Don Hershman

Stripe rust is very active at this time in parts of southwest Kentucky. Stripe rust is favored by cool weather, which has been prevalent across the state this spring. Additional spread into other parts of Kentucky is possible, so growers must remain vigilant. Stripe rust is evident as rows of bright yellow-orange pustules in short streaks following leaf veins. The disease tends to develop first in hot spots and then spread throughout the field when conditions favor infection. If left unchecked, stripe rust can devastate a crop. Fortunately, as seen in the table below, there are several fungicides available that can provide excellent control of stripe rust.

On April 22, the Kentucky Department of Agriculture (KDA) declared a crisis exemption for use of Folicur for the suppression of Fusarium head blight and DON in wheat. On April 29, the Environmental Protection Agency granted a section 18, emergency exemption, for Folicur that is good until the end of May. I wrote an extensive article on the use of Folicur for FHB/DON suppression in the last issue of the Kentucky Pest News. Concurrently, with the recent Folicur labeling activity, the KDA issued 24C, special local need, labels for PropiMax and Tilt. Both fungicides contain the active ingredient propiconazole and can now be legally applied until the crop begins to flower.

For additional guidance on comparative efficacy of available wheat fungicides, please review the following table.

NCR-184
Management of Small Grain Diseases

Fungicide Efficacy for Control of Wheat Diseases

The North Central Regional Committee on Management of Small Grain Diseases has developed the following information on fungicide efficacy for control of certain foliar diseases of wheat for use by the grain production industry in the U. S. Efficacy ratings for each fungicide listed in the following table were determined by field testing the materials over multiple years and locations by the members of the committee. Efficacy is based on proper application timing to achieve optimum effectiveness of the fungicide as determined by labeled instructions and overall level of disease in the field at the time of application. Differences in efficacy among fungicide products were determined by direct comparisons among products in field tests and are based on a single application of the labeled rate as listed in the table.

Efficacy of fungicides for wheat disease control based on appropriate application timing.
Product	Fungicide(s)	Rate/A	Powdery mildew	Stagonospora leaf/glume blotch	Septoria leaf blotch	Tan spot	Stripe rust	Leaf rust	Head scab
Tilt 3.6 EC	Propiconazole 41.8%	4 fl. oz.	+++*	+++	+++	+++	+++	+++	+
PropiMax 3.6 EC	Propiconazole 41.8%	4 fl. oz.	+++	+++	+++	+++	+++	+++	+
Quadris 2.08 SC	Azoxystrobin 22.9%	6.2 (to 10.8) fl. oz.	+(+)**	+++	+++	++++	++++	++++
Quilt 200SC	Azoxystrobin 7.0% Propiconazole 11.7%	14 fl. oz.	+++	+++	+++	+++	+++	+++
Stratego 250 EC	Propiconazole 11.4% Trifloxystrobin 11.4%	10.0 fl. oz.	++	+++	+++	+++	+++	++
Headline 2.09 EC	Pyraclostrobin 23.6%	6.0 (to 9.0) fl. oz.	++	+++	+++	++++	++++	++++
Folicur 3.6 EC***	Tebuconazole 38.7%	4.0 fl. oz.	++	+++	+++	+++	++++	++++	++

* the greater the number of + signs the greater the relative efficacy
** (+) indicates greater efficacy at higher application rates.
*** Folicur does not have a federal label, but may have Section 18 emergency registration in some states.

This information is provided only as a guide. It is the responsibility of the pesticide applicator by law to read and follow all current label directions. No endorsement is intended for products listed, nor is criticism meant for products not listed. Members of NCR-184 assume no liability resulting from the use of these products.

See "Insect Management Recommendations" for more wheat pest information.

EFFECTS OF VARIOUS COMPOSTS ON DAMPING OFF IN THE GREENHOUSE
By Paul Vincelli

A number of studies have demonstrated that composts can have disease-suppressive properties, which can help to reduce the activity of soil-borne pathogens should they be introduced into the production system. Usually suppression is due to microbial activity in the compost, although physical and/or chemical factors can also be involved.

A study from the University of Oregon was published in a recent issue of the journal Phytopathology (Scheuerell et al, 95:306-315, 2005) which examined the disease-suppressive properties of 36 composts available to local greenhouses. This article summarizes some of the results that are relevant to greenhouse growers.

Available Composts Were Highly Variable
As I inspected the data in this study, I was struck by how widely the composts varied in many parameters that could affect plant performance. Variation was especially wide in particle size, acidity, salt content, carbon-to-nitrogen ratio, and content of salt, ammonia, nitrate, and phosphorous. The take-home message on this point for me was, if you find a compost you like, stick with it.

Suppressiveness Against Pythium Damping Off
Pythium organisms are common fungal-like organisms that are favored by wet (especially saturated) conditions in the growing media. The researchers mixed each compost with peat and perlite (approx. volume ratio 7:6:1), and tested the level of disease suppression against two common Pythium species (P. ultimum and P. irregulare) on cucumber. Interestingly, 56% of the composts tested provided some reduction in damping off caused by both species. Taking their analysis a step further, the researchers considered a level of 80% healthy seedlings to be a minimally acceptable level for commercial production. By this standard, 44% of the composts tested effectively controlled both species.

One of the goals of research on disease suppressiveness is to be able to predict whether or not a particular lot of compost is suppressive to disease. The researchers analyzed each compost with a range of tests, including a commercially available compost testing kit called the Solvita Compost Maturity Test Kit. Use of this kit provides an estimate of microbial activity called the "Compost Respiration Potential (CRP)". In these assays, most of the composts with a moderate to high CRP exhibited some suppressiveness to Pythium species. This is generally consistent with other published studies, in that suppressiveness to Pythium is generally associated with increased overall microbial activity in a compost or soil. Unfortunately, the CRP was not an ideal predictor of suppressiveness, because there were a number of composts with low CRP values that were nevertheless moderately to highly suppressive. No other factor was useful for even a crude prediction of the level of suppressiveness of the composts studied.

Suppressiveness Against Rhizoctonia Damping Off
The fungus Rhizoctonia solani is the other major cause of damping off in greenhouses. The researchers mixed each compost with light sphagnum peat and vermiculite (5:4:1 volume ratio) and tested the level of suppression on cabbage. Of 36 composts, only six (17%) exhibited some suppressiveness to R. solani. Even worse, 44% of the composts tested actually increased the level of Rhizoctonia damping off compared to growing media not amended with compost (an experimental control).

Significance
Based on these results, one should not rely on composts to control these damping off diseases at this stage of the game. Research is continuing, and as we learn more about the factors involved in disease suppression, we'll be able to provide more intelligent and reliable guidelines about how to manage soilborne diseases using composts.

Adequate suppression of Pythium damping off 44% of the time is good news, but it's not good enough as a disease control practice for conventional growers. Organic producers usually are more tolerant than conventional producers of measures that provide partial or erratic control. Since many organic producers already use composts in horticulturally appropriate ways, they probably are getting some suppression of Pythium damping off from certain composts.

It was disappointing to see how few composts provided even partial suppression of Rhizoctonia damping off. Even worse, several composts that were suppressive to Pythium damping-off disease actually enhanced Rhizoctonia. To bring a bit of hope into the picture, note that in one experiment, the authors found they could enhance the level of Rhizoctonia suppression in a selected compost by mixing in another fungus that was antagonistic to R. solani. This approach might be a good way to deal with the potential for increased Rhizoctonia activity in compost-amended growing media, though it needs to be researched more.

In any case, whether the production system is conventional or organic, rely on sanitation and water management as the principal control practices for damping off. Use composts if they fit in your production system, but don't rely on them at this stage for control of damping off.

APPLES COULD BE AFFECTED BY SOYBEAN RUST MANAGEMENT
By John Hartman

Apple orchards growing near rust-infected soybean fields could be at risk of phytotoxicity from one of the fungicides proposed for soybean rust disease management. The fungicide azoxystrobin, labeled as Quadris for Asian soybean rust control, is phytotoxic to MacIntosh and MacIntosh-derived varieties of apples. Besides Quadris, azoxystrobin is also sold under the trade names Abound and Heritage. Azoxystrobin is registered on grapes, several tree nuts, stone fruit, cucurbits, and other horticultural crops, but not on apples.

Phytotoxic symptoms on apple trees include leaf and twig necrosis (dead tissue), leaf drop and fruit drop. Conditions favorable for drift have caused problems to apples elsewhere, e.g., azoxystrobin used in grape vineyards adjacent to apple orchards. The current label warns about spray drift and prohibits sprayers used with azoxystrobin for subsequent spraying of apple trees. Use of Quadris for soybean rust management could cause problems for apple orchards or backyard trees adjacent to soybean fields, especially under unanticipated conditions favorable for drift.

Apple varieties known to be adversely affected are Akane, Asahi, Bramley, Courtland, Cox's Orange Pippin, Cox, Delbarestival, Discovery, Gala, Galaxy, Grimes, Imperial Gala, Kent, Kizashi, Lurared, McCoun, MacIntosh, Molly Delicious, Mondial Gala, Ontario, Queen Cox, Royal Gala, Spartan, Stark Gala, Starkpur Mac, Summared, Summer Treat, Warabi, Worcester, and Pearmain.

Apple growers are urged to communicate with neighboring soybean farmers about plans for soybean rust management. Fortunately, soybean growers have many other fungicide options to choose from, many of them less expensive than azoxystrobin. Thus, with good planning, soybean rust can be managed effectively with little risk to nearby apple crops.

Information for this article was adapted from the April 20, 2005 edition of the Kansas State University Extension Plant Pathology Plant Disease Alert newsletter, written by Doug Jardine.

LEAF SPOT & MELTING OUT
By Paul Vincelli

Repeated periods of cool, rainy weather this spring are favorable for infections of Kentucky bluegrass by the fungus that causes leaf spot and melting out. Infections of the leaf blade and sheath appear as oval, purple or brown spots that may develop a light center as they expand. This damage is usually not significant and is usually only noticeable to those who get on their knees and inspect for it. However, in older or poorly adapted varieties, these infections can be followed by the melting out phase in summer, as the infections progress into the crown.

Melting out looks a lot like drought damage. The turf wilts and dries up over large areas. The difference is, since melting out is the result of infection, this symptom develops even if the soil has adequate moisture.

The best solution is to renovate the lawn with tall fescue or, if Kentucky bluegrass is preferred, a resistant variety of Kentucky bluegrass. Information on the best varieties for Kentucky can be found at the UK Turf Center web site at http://www.uky.edu/Agriculture/ukturf/.

Avoid high nitrogen fertility in the spring and reducing excessive thatch can also help. Although I would discourage the use of fungicides for this purpose, several fungicides are effective and can be found listed in the Extension publication, Chemical Control of Turfgrass Diseases, PPA-1", available online at http://www.ca.uky.edu/agc/pubs/ppa/ppa1/ppa1.pdf.

DIAGNOSTIC LAB - HIGHLIGHTS
By Julie Beale and Paul Bachi

Samples diagnosed during the past week have included cold injury on wheat; sunscald, Pythium root rot, and target spot on tobacco; and sunscald, fertilizer burn and cold injury on (greenhouse) tomato and pepper seedlings.

On greenhouse ornamentals, we have diagnosed boron deficiency on petunia and black root rot on vinca. On landscape ornamentals, we have seen Didymellina leaf spot on iris; iron deficiency and winter injury on holly; Kabatina twig blight on juniper; black knot on ornamental cherry; winter injury, wet feet symptoms, Rhizoctonia root rot, and Pseudonectria canker on boxwood; and fireblight and growth regulator injury on pear.

By Patty Lucas, University of Kentucky Research Center

For information on trap counts in southern Illinois visit the Hines Report at - http://www.ipm.uiuc.edu/pubs/hines_report/comments.html The Hines Report is posted weekly by Ron Hines, Senior Research Specialist, at the University of Illinois Dixon Springs Agricultural Center.

NOTE: Trade names are used to simplify the information presented in this newsletter. No endorsement by the Cooperative Extension Service is intended, nor is criticism implied of similar products that are not named.

Lee Townsend
Extension Entomologist

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