Fresh, senesced, and decaying pine needles from Pinus halepensis were evaluated for their allelopathic potential on Festuca arundinacea, Cynodon dactylon and the biosensor plants Avena sativa and Lemna minor through in vivo and in vitro studies. The in vivo study was performed in growth chambers, using 6, 12, and 18 g of pine needle tissue mixed with screened perlite as a substrate. The effects...

A systematic collection of throughfall (rain passing through the canopies), stemflow (rain flowing over the stems), and soil percolates was carried out in a Acacia dealbata plantation during one year, and its allelopathic capacity was biotested using Lactuca sativa L. var. Great Lakes. The results showed an allelopathic effect related to flowers: Germination of L. sativa was inhibited 30% by th...

We have identified through bioassay guided isolation an allelochemical, eudesmane-type sesquiterpeniod, 3beta-caffeoxyl-beta1,8alpha-dihydroxyeudesm-4(15)-ene (1), from an endemic plant species growing in the Himalayas. In our search for the bioactive subfraction, the hexane one was highly significant, showing 100% inhibition of lettuce seed growth at 100 ppm while other subfractions (chlorofor...

Bothriochloa laguroides var. laguroides (DC.) Herter, a native bluestem of America, has been shown to produce many biologically active compounds. The allelopathic potential of aqueous extracts from roots, stems and leaves was examined. Lettuce seeds (Lactuca sativa) and maize (Zea mays), the common allelopathy bioassay systems, as well as seeds from two native species, wintergreen paspalum (Pas...

Laboratory experiments were conducted to evaluate the allelopathic effects of the water extract of Argemone mexicana L. on the seed germination, plumule length, radicle length, fresh and dry weight in Sorghum (Sorghum bicolor Moench). The allelopathic potentialities of leaf extracts of A.mexicana decreased the seed germination of Sorghum bicolor with raise of extracts concentration. The extract...

Phytoplankton have been shown to compete for light and nutrients through different physiological and biochemical adaptations, such as, variation in surface area to volume ratio, production of specific enzymes, different nutrient requirements, luxury uptake, pigment composition, photosynthetic capacity, mixotrophy and vertical migration. Algal proliferations with respect to competition are part ...

In this article we have considered a stochastic delay differential equation model for two species competitive phytoplankton system with allelopathic stimulation. We have extended the deterministic model system to a stochastic delay differential equation model system by incorporating multiplicative white noise terms in the growth equations for both species. We have studied the mean square stabil...

A laboratory experiment was conducted to determine the allelopathic effect of residues aqueous extract of two ecotype of swallowwort (Cynanchum acutum L.) on germination traits of wheat (Triticum aestivum L.). A factorial experiment based on a completely randomized design with four replications was conducted at Islamic Azad University of Karaj in 2012. Factors were two swallowwort ecotype (Ghaz...