Diseases and Pests

Black Shank


Black Shank can infect tobacco plants of any age. In young transplants, the stem can be affected near the soil surface, while the root system may become partly or completely black. Symptoms can be confused with damping-off caused by other organisms. In adult plants, a blackened lesion is observed at ground level and can spread to the stem.

Leaves may uniformly wilt overnight, turning yellow and wilting while still on the stem. If the stalks are split longitudinally along the infected portion of the stem, plate-like disks will be observed. Hot weather conditions and humidity favor Black Shank development. Advanced stages of this disease may cause partial or complete decay of the root system.

Under rainy crop conditions the plants may survive. However, stresses caused by dry weather conditions or hot temperatures normally kill the infected plants due to the collapse of the water absorption system.

The Black Shank fungus Phytophtora parasitica var. nicotianae survives in the soil and is easily spread to non-infected areas by equipment or through water. As the spores of the fungus are mobile, the distribution of the disease within a field may not be uniform. There are two known types of Black Shank, race 0 and race 1, and they are easily confused.

The most important management practice for the control of Black Shank is the use of resistant cultivars, but registered and approved fungicides are also efficient. Crop rotation and nematode control are also important, because nematodes pave the way for Black Shank to infect tobacco.

The destruction of crop waste/remains plays an important role in the control of Black Shank.

ProfiGen released several cultivars and hybrids with good resistance and/or tolerance to the different types of Black Shank. It is extremely important to identify which type of Black Shank has infected the field in order to opt for the most appropriate cultivars for every situation.

 

Symptom disease pictures:


 Initial symptom of plant infected by Black Shank.

 Black Shank at ground level.

  Disking of the pith of a plant infected with black shank

 Comparison between resistant and susceptible cultivars in black-shank infested field

 

See also



Related products


  • NC71
    Black Shank - Resistant

  • NC72
    Black Shank - Resistant

  • PVH1452
    Black Shank - Resistant

  • PVH1600
    Bacterial wilt tolerant

  • PVH2233
    PVY - Resistant

  • PVH2261
    PVY - Resistant

  • PVH2275
    Nematode - Resistant

  • PVH2310
    Early maturity

  • PVH2324
    Early maturity

  • PVH2329
    Yellow Stunt - Tolerant

  • PVH2340
    Nematode - Resistant

  • PVH2356
    Nematode - Resistant

  • PVH2376
    Nematode - Resistant

  • PVH2404
    PVY - Resistant

  • PVH2408
    Nematode - Resistant

  • HB4155P
    Fusarium and Bacterial Wilt - Tolerant

  • HB4167P
    Black Shank - Resistant

  • HB4192P
    Black Shank - Resistant

  • HB4488P
    Nematode - Resistant

  • KT204LC
    Black Shank - Resistant

  • KT206LC
    Black Shank - Resistant

  • KT209LC
    Black Shank - Resistant

  • KT210LC
    Black Shank - Resistant

  • KT212LC
    Black Shank - Resistant

  • PD7309LC
    Dark Hybrids

  • PD7318LC
    Dark Hybrids

  • POH6002
    Oriental Hybrids