According to the present invention, an agricultural and horticultural fungicide that effects can be reliable and safe to use, as well as useful pyridine compound or salt thereof as an active ingredient of the agricultural and horticultural fungicide is provided. Pyridine compounds or salts thereof of the present invention are those represented by the following formula. In the formula, R 1 is such as formyl group, R 2 is such as a hydrogen atom, R 3 , R 4 and R 5 are each independently, a hydrogen atom, E is a phenyl group, a is a halogen atom, n represents each represent an integer of 0 to 5. [Formula 1]本発明により、効果が確実で安全に使用できる農園芸用殺菌剤、並びに農園芸用殺菌剤の有効成分として有用なピリジン化合物またはその塩が提供される。本発明のピリジン化合物またはその塩は、下記の式で表されるものである。式中、R1はホルミル基など、R2は水素原子など、R3、R4およびR5は各々独立して、水素原子など、Eはフェニル基など、Aはハロゲン原子など、nは0~5のいずれかの整数をそれぞれ表す。【化1】
