Cultivation Now Underway

The majority of the crop was planted in May under cooler and wetter conditions, which were not overly stressful to transplants. At this time, most crops appear to be off to a good start, with cultivation now starting to occur on several farms.  Cultivation in combination with daytime temperatures that are expected to rise to the upper 20’s and low 30’s (°C) over the next several days, should help promote root development and good plant establishment.

View across CTRF’s variety trials in the Delhi area on June 8, 2017 just prior to cultivation.

Plant problems observed in greenhouses this spring include high salts in the seedbed, heat damage, nitrogen deficiency, chemical injury, aphids, Damping-Off from the organisms Rhizoctonia and Pythium, Bacterial Rot and Black Root Rot.

Transplants infected with Black Root Rot (caused by the fungus Thielaviopsis basicola) from the greenhouse can result in an uneven crop throughout the growing season.  Black Root Rot infected plants are later to develop resulting in later topping and maturity.

Root of greenhouse seedling infected with Black Root Rot.

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.  Every year for the past several years we have encountered Black Root Rot in styrofoam plug trays when steam has not been used to disinfect them.  Disinfection of styrofoam plug trays with steam is the only practice that will control Black Root Rot.  Some growers who do not follow this practice feel that because they have never had the disease in the past this trend will continue in the future.  Unfortunately, the stats suggest that there is a better chance of getting Black Root Rot in trays if they are not disinfected with steam than winning the lottery!  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.

In the field, there have not been many problems reported as of yet. To date, there have been a few reports of fumigant injury, and a case where one of the fertilizer bands at planting was too close to the plants and caused injury.

There continues to be only one report of Blue Mold in tobacco from the United States. This report came from Georgia in March where Blue Mold was found in two flue-cured tobacco greenhouses.  Up until now, there have been no reports of Blue Mold here in Ontario.  Growers should routinely scout fields and any leftover plants in the greenhouse 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.

Post prepared and sent by Canadian Tobacco Research Foundation

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

Telephone: 519-842-8997

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