Climate-related diseases

The non-parasitic (abiotic) diseases are often linked either to an adverse environment or to poor agricultural practices. Here we will describe the most common ones.
 
Currently tobacco nurseries in France are not heated. It has been quickly forgotten that tobacco is a plant of a tropical origin and thus may require warmer temperatures than those in the nursery. Warmer temperatures certainly favour the germination of the seeds and improve the quality and consistency of the obtained seedlings.
 
Seedlings are highly sensitive to cold; affected young leaves are partially or completely translucent and tend to become spoon-shaped (figure 1). Subsequently, affected leaves may be distorted and show discolorations (figure 2). It should be noted that tobacco varieties do not show the same sensitivity to cold (figure 3).
 
Otherwise, once we begin to uncover the nurseries, a cold wind, heavy rain or hail ... may cause damage to the very soft tissues of seedlings (figures 4 and 5).