Allelopathic Effects of Yarrow (Achillea milefolium L.) and Lemon-Verbena (Lippia citriodora Kunth.) on Germination of Some Weed Species

Subject Areas : Semi Annual Journal of Weed Ecology

Elham  Atarod ¹ (دانش آموخته کارشناسی ارشد رشته شناسایی و مبارزه با علفهای هرز دانشگاه آزاد اسلامی واحد گرگان)
Asiyeh  Siahmarguee ² (استادیار دانشگاه علوم کشاورزی و منابع طبیعی گرگان)
Mahsa  Alimi ³ (استادیار دانشگاه آزاد اسلامی واحد گرگان)

Received: 2014-12-15 Accepted : 2015-06-23 Published : 2016-02-20

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Abstract :

Concerns about environmental pollutions and development of weed resistance to herbicides have attracted the attentions towards the biological control of weeds. In order to evaluate the allopathic effects of different organs of yarrow (Achillea milefolium L.) and lemon-verbena (Lippiacitriodora Kunth.) on germination of redroot (Amaranthus retroflexus ­L.), wild mustard (Sinapis arvensis­ L.), and  little seed canary grass (Phalaris minor Retz.), a factorial experiment was conducted in a completely randomized design with four replications at Research Laboratory of Islamic Azad University of Gorgan in 2014. Treatments included medicinal plant  at 2 levels(Yarrow and lemon-verbena), organs of medicinal plants at 3 levels (root, stem and leaf), and concentrations of extracts at five levels (0, 25, 50, 75 and 100 v\v%). By increasing the concentration of yarrow and lemon-verbena, the germination rate of seeds, plumule length, radical length and seedling fresh weight in  weed species were significantly reduced. Allopathic effects of leaf and shoot extracts of lemon-verbena were severe on seed germination of mustard. Allelopathic effects of leaves and stems of limon-verbena on wild mustard seeds and yarrow extract on the germination of weed seeds was high. Among the three weed species,  little seed canary grass was less affected by the extract of yarrow and lemon-verbena. Given the importance of reducing the use of chemical inputs in the management of weeds, use of the potential inherent of some plants and their application in agricultural systems and planning rotation can be very handy and useful.