Harvest is underway on all farms with some growers still working on the first pass while others are on their second pass.  The quality of tobacco cured so far appears good.  There are no widespread problems being reported at this time.  Currently, pressure from aphids and hornworms is not very significant in most fields.  A few plants in some fields are showing infection from Potato Virus Y (PVY).  White Mould (Sclerotinia sclerotiorum) is also being seen on a few plants in some fields as well.  Certain varieties are showing more spotting (1-3 mm in diameter) on field leaves than others.  The cause of this is from air pollutants and the variety’s susceptibility to this injury.  The spots are initially brown or black and eventually will turn to grey or white.  To date, there have been no reports this season of Blue Mold in Ontario.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com

Syngenta Canada has decided to end sales of Actigard 50WG in Canada after the 2015 growing season because of declining sales.  Actigard 50WG  is registered for the control of Blue Mold in tobacco and will be available to purchase until October, 2015.  After this date, the product will no longer be available in Canada, however, the Canadian registration for Actigard 50WG will be maintained so growers who have product can still use it on their tobacco beyond this year.  Use of Actigard 50WG should be within three years of purchase according to Syngenta.

Other products registered and recommended for the control of Blue Mold in tobacco are Aliette WDG and Quadris Flowable.

For more information, refer to the ONspecialtycrops blog.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com

Currently most crops are in the rapid growth stage.  Earlier planted fields are at or approaching the stretch–bud stage.  Topping has already begun on some farms.

Field at stretch-bud stage, which is ideal time for topping. Delayed topping can reduce yield up to 27.5 kg/ha per day.

Aphids are starting to be seen in several fields.  Scouting of fields, particularly around a field’s perimeter should be undertaken to determine if the treatment threshold has been reached.  OMAFRA’s Publication 843, Flue-Cured Tobacco Crop Protection Guide, provides information on thresholds, products and rates for control of aphids and other insects.

Stink bugs are being seen in several tobacco fields, however, there have not been any situations observed where significant economic loss has occurred.

Tobacco plant showing symptoms of feeding from stink bugs. Leaves in growing point are wilted. A stink bug can be seen on the plant’s stalk just below the lowest wilted leaf.

Frequent and abundant rains earlier in the season caused leaching of nitrogen in several fields and resulted in the tobacco in some of these fields to turn pale in colour.  Most growers have been actively applying nitrogen to compensate for leaching losses.   This week we are seeing much better colour in several of these fields.

On some farms, nematode injury to tobacco roots in sandier areas of fields has been observed.  Plants in these areas tend to be uneven with the smaller plants having root damage from root-lesion nematodes.  Soil conditions were less than ideal when fumigation occurred on some farms, which reduced the effectiveness of the fumigant.  In addition, root growth earlier in the season has been less than it would have been normally had it been drier and warmer.  As a result, nematode feeding on a plant with a less developed root system has had a greater effect than if the roots had been more actively growing.

There has been further incidence of Black Root Rot affecting tobacco growth in fields. The origin of the disease was again determined to be from greenhouse trays.  Unless Styrofoam plug trays are properly sterilized following use each year, it is not uncommon for the fungus to build up in the trays and infect the plants.  Disinfection of Styrofoam plug trays with steam is advised to control Black Root Rot.  For more information on Black Root Rot and its control, please refer to the technical bulletin entitled “Tobacco Pests and Disorders in the Field – Black Root Rot” posted in the Plant Protection area of this website.

Earlier this month, we started to see symptoms of infection from Potato Virus Y (PVY) on a small number of tobacco plants in some fields.  It is not known as to how significant PVY will become this year. Spread of PVY is primarily by aphids.  Control of aphids in tobacco may help to reduce spread of the disease from infected plants within a tobacco field.  For more detailed information about PVY, please refer to the technical bulletin entitled “Tobacco Pests and Disorders in the Field – Potato Virus Y” posted in the Plant Protection area of this website.

Tobacco plant showing symptoms of the necrotic strain of Potato Virus Y (PVY).

There have been further reports of Blue Mold in the United States. In Connecticut and Massachusetts, Blue Mold has been found on broadleaf and shade tobacco.  States reporting the disease earlier were Pennsylvania and Tennessee.  Up until now there have been no reports of Blue Mold in Ontario.  Growers should routinely scout fields for signs of Blue Mold.  Information about identification of Blue Mold and its control can be found in the technical bulletin entitled “Tobacco Pests and Disorders in the Field – Blue Mold” posted in the Plant Protection area of this website and in OMAFRA publications 842 and 843.  If you find Blue Mold, please report it immediately.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com

On June 24th, 2015 a second state in the U.S. reported Blue Mold.  In Lancaster County, Pennsylvania active spores were found on tobacco in a plant bed and in a neighbouring field.  Blue Mold was first reported in Greeneville, Tennessee on June 2nd, 2015 where it was found in greenhouses and on plants that had gone out to the field earlier from these greenhouses.  Up until now there have been no reports of Blue Mold in Ontario.  Growers should routinely scout fields for signs of Blue Mold.  Information about identification of Blue Mold and its control can be found in the technical bulletin entitled “Tobacco Pests and Disorders in the Field – Blue Mold” posted in the Plant Protection area of this website and in OMAFRA publications 842 and 843.  If you find Blue Mold, please report it immediately.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com

Most crops are showing good progress at this time. The after effects of sandblasting on plants in open areas of fields from high winds at planting and early last week can be seen in some fields. The affected plants have been setback and are smaller, but will recover. Otherwise most crops appear quite uniform.

CTRF’s variety trials located near Delhi, ON on June 17, 2015

Most areas have seen a considerable amount of rain in just over two weeks. At Tillsonburg, rainfall from May 30^th to June 15^th has totalled 132.8 mm (5.23 in). No doubt there has been some leaching of nitrogen since transplanting. With side-dressing approaching, there will likely need to be some compensation.

To date there have been few field problems reported.

During replanting there were complaints of white grubs and cutworms causing damage to plants.

Injury from high salts, caused by one of the fertilizer bands at transplanting being too close to the plants, has been another problem encountered. Wet soil conditions have helped in this case to reduce the effects of the high salts being caused by the closeness of the fertilizer band to the plants.

Injury from Black Root Rot, caused by the fungus Thielaviopsis basicola, has been seen as another problem on plants in the field.  Typical symptoms are uneven plant growth with the slower growing plants having dark lesions on the roots.  In one case, the infected plants were grown in styrofoam plug trays in the greenhouse prior to transplanting.  Unless the Styrofoam plug trays are properly sterilized following use each year, it is not uncommon for the fungus to build up in the trays and infect the plants.  Disinfection of Styrofoam plug trays with steam is advised to control Black Root Rot.  For more information on Black Root Rot and its control, please refer to the technical bulletin entitled “Tobacco Pests and Disorders in the Field – Black Root Rot” posted in the Plant Protection area of this website.

There continues to be only one report of Blue Mold in tobacco from the United States. This report came from Greeneville, Tennessee on June 2, where Blue Mold was found in greenhouses and in plants that had gone out to the field earlier from these greenhouses. Up until now there have been no reports of Blue Mold in Ontario. Growers should routinely scout fields and any remaining plants in greenhouses for signs of Blue Mold. Information about identification of Blue Mold and its control can be found in the technical bulletin entitled “Tobacco Pests and Disorders in the Field – Blue Mold” posted in the Plant Protection area of this website and in OMAFRA publications 842 and 843. If you find Blue Mold, please report it immediately.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com

Planting of the crop is mostly complete with the majority of it having been done in May.  Plant quality has been good going out into fields.  Rainfall this past weekend helped to alleviate dry soil conditions that had persisted over most of May.

To date, there have not been many problems reported.  Earlier, there was frost damage to some plantings made prior to May 23rd.  High winds during the week of May 25th did cause some sandblasting to plants on knolls in fields, especially in fields without windbreaks.  There have been a few reports of white grubs feeding on the stems of plants below ground, which was noticed while replanting.

On June 2nd, active Blue Mold was found in tobacco greenhouses in Greeneville, Tennessee.  Infected plants from these greenhouses had gone out to the field prior to the disease being discovered.  It is suspected that the Blue Mold resulted from air-borne spores that originated from the Gulf of Mexico region over the past two weeks.  At this time, this is the only report of Blue Mold in the tobacco growing areas of the United States.  To date, there have been no reports of Blue Mold in Ontario.  Growers should routinely scout fields and any remaining plants in greenhouses for signs of Blue Mold.  If found, please report it immediately.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com

Most greenhouses appear to have good seed germination and seedling uniformity.  At the current time, seedlings between farms do vary in size depending on the type of production method being used and when seeding was started.

In some of the earlier seeded greenhouses a preventative application of fungicide has been made for the control of Rhizoctonia Damping-off.  Clipping has started in some of the float tray greenhouses, while in some of the muckbed greenhouses, the seedlings have not yet filled in the seedbed.

Chilling Injury

Some concerns have been expressed regarding the amount of chilling injury being observed in some greenhouses.  The initial symptoms are often a bright yellow colour in the growing point of the seedling and upward cupping of the leaves (as shown below).

Chilling injury

As the seedlings become larger and the leaves grow out, some leaves will be malformed, cupped and have a distinct yellow/white discolouration.  Seedlings do outgrow chilling injury without any ill-effects on the seedlings when transplanted to the field.

Chilling injury is caused by exposure of the seedlings to a large variation in air temperature in the greenhouse.  This can happen when ventilation occurs on a very cool but sunny day or at night when the temperature outside is quite cold and the temperature drops significantly in the greenhouse because the heaters do not have enough capacity to maintain the set temperature.  Also, some varieties are more susceptible than others to chilling injury.

Effects of Algae on Emerging Seedlings in Trays

Certain algae present on the surface of tray media can affect seedling emergence and establishment.  Two situations are usually seen in these cases, one where the seedlings are not able to emerge through the algae and the other being where the seedlings emerge, but cannot establish themselves before succumbing to the algae and dying (as shown below).

Seedling in left cell (light brown in colour) has succumbed to algae.

At this time of the year, growers typically see the after-effects of the algae, either empty cells or seedlings that only reached the 2-leaf stage and turned brown.

Cool and cloudy weather conditions are ideal for algae growth.  Some algae, such as the green algae, possess motile appendages that allow them to move in the presence of water in tray media as seen in a video in the plant protection area of the website.  This suggests that spread of algae in a tray can occur from cell to cell.

There are no chemical treatments for algae in tobacco greenhouses.  Conditions that are optimum in the greenhouse for rapid seed germination and early seedling growth help seedlings to outpace the algae so that the seedlings become large enough that the algae can no longer affect them.  Not fertilizing for 2 or 3 weeks after seeding can also help to prevent an early buildup of algae in trays.  As seedlings grow, the canopy will close over and shade the media surface, therefore, reducing the negative effects of algae.

Further information about algae and measures to reduce its effect on seedlings can be found in a technical bulletin in the plant protection area of this website.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com

Now that seeding of greenhouses is done for this year, there have been some inquiries as to storing leftover pelleted tobacco seed until next year.  Information about the storage of seed can be found in the Plant Breeding area of the website.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com

Growers who plan to use a soil fumigant in 2015 should be aware that there are several new label requirements and they should read and understand the entire label before using the fumigant.  Some of the new label requirements for fumigants are indicated in an article prepared by the CTRF in the Plant Protection area of this website.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com

The Tobacco Review and Evaluation Committee (TREC) has found Pic Plus Fumigant to be acceptable to use for flue-cured tobacco production. Pic Plus Fumigant is a registered product that is labelled for tobacco. Read and understand the entire label before using this product or any other registered and TREC approved soil fumigant. Soil fumigant labels now have several new requirements, which must be followed when using these products.

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Mailing Address: CTRF, P.O. Box 322, Tillsonburg, ON  N4G 4H5

Telephone: 519-842-8997

Web Address: http://ctrf1.com