Abstract: | Pluchea lanceolata (DC.) C.B. Clarke (Asteraceae) is a rapidly spreading perennial weed in semiarid areas of north‐west India. While preparing fields for cultivation, farmers incorporate Pluchea plant debris into the soil. In the present study, mustard grown in plots with soil‐incorporated Pluchea had significantly reduced shoot height (61 ± 8.8 cm), number of pods per plant (7 ± 3.2), number of seeds per pod (4.1 ± 3.9) and weight per seed (0.08 ± 0.03 g) of mustard compared to mustard growing in Pluchea‐free soils. Pluchea‐infested and Pluchea‐free soils were analyzed for pH, electrical conductivity, organic matter, soluble chloride, exchangeable phosphate, copper, zinc, sodium, potassium, magnesium, calcium and water‐soluble phenolics. Pluchea‐infested soils had different values for electrical conductivity, Cl, K and total phenolics when compared to Pluchea‐free soils. Data on yield reduction of mustard due to soil‐incorporated Pluchea leaves have been reported for the first time. The reduced mustard growth and yield is proposed to be partly due to water‐soluble phenolic compounds contributed by Pluchea leaves into soil. |