The dark brown lesions on the leaves will swiftly get larger in warm and humid conditions, causing chlorosis and considerable defoliation, leading to sunscald. The blight spreads throughout the fruit via insect attachment points or wounds, contaminating the entire fruit. DamageĮarly blight can cause collar rot, which renders stems dark, dry, and depressed and causes seedling mortality. Mature lesions may develop velvety patches of fungal spores, whereas fruit spots are black, leathery, and have elevated concentric rings. Lesions on the foliage may become yellow. The blight appears initially in the oldest leaves of tomatoes as little brown-black, dry, papery patches with concentric rings up to half an inch in diameter. Early blight on tomato plants is distinguished by lesions that resemble bull’s-eyes. solani produces tomato blight in areas where A. tomatophila is the primary cause of tomato blight. tomatophila is far more dangerous than A. 2003).Ĭredit Jerzy Opioła, CC BY-SA 4.0via Wikimedia Commons Early Blight IdentificationĮarly blight can develop as a result of Alternaria tomatophila or Alternaria solani fungus infection. In general, tomatoes prefer acidic soil with low levels of nitrogen (N) fertilizer applied during vegetative growth stages however, some varieties may prefer higher levels than others (Gralinski et al. Tomato plants need warm soil temperatures between 20☌ and 30☌ (68☏ and 86☏) with at least 6 hours of sunlight a day for optimal growth rates throughout their lifecycle (Flannigan & Sloane 1998). When growing tomatoes, it is important to ensure that they are planted at the right time of year for their area of origin and climate conditions (i.e., early spring or late summer). It quickly spread throughout Europe and was later introduced to North America by Spanish colonists. It was first cultivated in Mexico and Central America before spreading to Spain during the 16th century. The species is believed to have originated in South America. It is grown in a variety of ways, including as an annual or biennial plant, as a vine or as a perennial herb.

The tomato is a popular fruit and vegetable crop in many parts of the world.

Tomato blight treatment