Allelopathic Effect of Parthenium hysterophorus on Germination and Growth of Some Important Crops and Weeds of Economic Importance

Abstract

Parthenium hysterophorus being a declared invasive weed worldwide is threatening the biodiversity of Pakistan. To study its allelopathic potential, laboratory and pots based studies were undertaken during July-August and October-November, 2010 in Weed Research Laboratory, Department of Weed Science, The University of Agriculture Peshawar, Khyber Pakhtunkhwa Pakistan. The experiments were conducted to investigate the allelopathic effect of parthenium on crops Triticum aestivum, Cicer arietinum and Brassica campestris, and weeds including Avena fatua, Asphodelus tenuifolius and Lolium rigidum The fresh leaves of P.hysterophorus were dried in shade and grinded. The desired quantity of powder was soaked for 16 hr. in the desired quantity of water to make the stock solution of the maximum concentration viz. 75 g L-1. Five seeds of each species were placed in Petri dishes and in pots, extracts were applied when needed. Control (0 g L-1) was also included for comparison. Both experiments were laid out as Factorial in completely randomized design (CRD) with four replications and two runs each. Since the statistical differences between the runs were non-significant the data were pooled before subjecting it to ANOVA and mean separation. The differences among the test species and the rates of parthenium extracts were different statistically (P?0.05) for all the traits examined, while for the species x parthenium concentration interaction, the differences were only significant (P?0.05) for plant height in the pot experiment. The results showed that with the increasing concentration of P. hysterophorus, all the parameters studied in the six test species were significantly decreased. Hence, the present study suggests that P. hysterophorus affects the agro-ecosystem and needs to be properly managed, moreover, its allelopathy on weeds is an encouraging finding for the weed managers for the sustainable management of weeds.

The latitudinal and longitudinal allelopathic patterns of an invasive alligator weed (Alternanthera philoxeroides) in China

“…This might because that the LA of L . sativa is promoted by the low concentration of the aqueous extracts, in accord with former studies [ 35 ]. Overall, the different responses of the determined characteristics of the target species to the allelopathy is clearly due to their different sensitivity or the index specificity within a species [ 36 – 38 ].…”

The in vitro, ex vivo, and in vivo experimental findings of Nephrolepis exaltata

“…Allelochemicals are present in almost all plant tissues (leaves, flowers, fruits stems, roots, rhizomes, seeds, and pollen), and are released to the environment through volatilization, leaching, root exudation, and decomposition of plant residues (Sangeetha and Baskar, 2015). The mechanisms by which allelochemicals act to inhibit germination, shoot, and root growth of other plants, involves the nutrient uptake destroying the plant's usable source of nutrients (Hassan et al, 2018), among others such as a generalized reduction in mitotic activity in roots and hypocotyls, hormone activity, rate of ion uptake, photosynthesis, respiration, protein formation, the permeability of cell membranes and/or enzyme action (Chang and Cheng, 2015). The presence of terpenes was identified, but not flavonoids, in N. exaltata aqueous extract (Sanchez et al, 2018), and it is known that terpenes inhibit the nitrification of soil, influencing the productivity of a plant community (Coskun et al, 2017).…”

Ecological Traits and Socio-Economic Impacts of the Alien Invader Weed Parthenium hysterophorus L. in South Africa’s Rangeland Ecosystems: A Review

“…Allelopathy is a phenomenon observed in many invasive plant species that involves the release of secondary compounds by a plant that affects the growth of surrounding plants in a stimulatory and inhibitory manner. Hassan et al [70] reported that releasing allelochemicals in low amounts stimulates growth, while greater amounts result in the inhibition of surrounding plants. Allelopathy is one of the fundamental mechanisms responsible for the success of invasive alien plant species.…”