Biology and Dispersal Mechanisms of Parthenium hysterophorus as an Invasive Weed in Agricultural Ecosystems

Abstract

Parthenium hysterophorus is one of the most aggressive invasive weeds in agricultural ecosystems, causing severe ecological disruption, crop yield losses, and health hazards due to its rapid spread and allelopathic potential. The present study investigated the biology and dispersal mechanisms of P. hysterophorus across different agroecosystems. Field observations and controlled experiments were conducted to examine germination behavior, growth characteristics, reproductive potential, and seed dispersal pathways. The results indicated that P. hysterophorus exhibits high reproductive efficiency, rapid growth rate, and strong adaptability to diverse environmental conditions. A single plant produced a large number of seeds with prolonged viability, contributing to persistent soil seed banks. Germination was influenced by soil moisture, temperature, and light availability, with optimal conditions favoring rapid establishment. Dispersal occurred primarily through wind, water runoff, contaminated crop seeds, agricultural machinery, and livestock movement, facilitating wide spatial distribution across fields and non-cultivated areas. The species demonstrated strong colonization ability in disturbed soils, roadside habitats, and cropped lands, outcompeting native vegetation through resource competition and allelopathic interference. Seasonal patterns showed peak emergence during warm and moist conditions, aligning with crop growth stages and increasing competition intensity. The study highlights the ecological plasticity and multiple dispersal strategies that contribute to the invasive success of P. hysterophorus. These findings provide important insights into its population dynamics and spread mechanisms, supporting the development of integrated weed management strategies aimed at containment, early detection, and long-term suppression in agricultural landscapes.