Role of VAM in alleviating allelopathic stress of Parthenium hysterophorus on maize (Zea mays L.)

Experiments were conducted to evaluate the impact of allelopathic potential of Parthenium hysterophorus on germination, growth and yield of maize (Zea mays L.) as well as the role of Vesicular Arbuscular Mycorrhizae (VAM) in alleviating allelopathic stress. In the first experiment germination and seedling growth response of maize to 5, 10, 15, 25 and 50 % w/v aqueous extract of P. hysterophorus was studied in petri dishes. Higher concentrations of 25 and 50% aqueous extract of Parthenium significantly reduced the germination of maize grains. Root and shoot growths of seedlings were also similarly affected. In the other experiment, shoot material of P. hysterophorus was cut into very small pieces and mixed in the heat sterilized pot soil @ 0, 5 and 10 % w/w, half the pots were inoculated with VAM. The results regarding the various vegetative and reproductive growth parameters revealed that the maize crop was not susceptible to applied rates of P. hysterophorus Mulch, the maize growth was considerably enhanced in 5 % treatment while in 10 % mulch treatment crop growth was as good as in control while plants inoculated with VAM showed markedly enhanced the crop growth both in control as well as Parthenium mixed treatments. Mycorrhizal colonization was markedly suppressed by mixing shoot material of P. hysterophorus at vegetative growth stage especially in 10 % treatment.&nbsp