Comparison of allelopathic effects of some brassica species in two growth stages on germination and growth of sunflower

Abstract

Members of Brassicaceae have been frequently cited as allelopathic crop. The toxic effect of Brassica spp. may be caused by hydrolysis products of glucosinolates that occur in substantial amounts in the vegetative parts of Brassica spp. This study investigated the allelopathic potential of Brassica napus, B. rapa and B. juncea on the sunflower seed germination and seedling growth. Aqueous extracts of three species from two stages (full flowering and straw) of sampling were separately made with 0 (distilled water), 10, 20, 30 and 40% concentrations. This experiment was conducted in 2 × 3 × 5 factorial arrangement based on completely randomized design with five replications. There was a highly significant difference among different concentrations of extracts and also between two stages of extraction. All aqueous extracts significantly affected sunflower germination, germination rate, seedling root and hypocotyl length, fresh and dry matter weight when compared with distilled water control. The greatest concentration showed a stronger inhibitory effect. Root length was more sensitive to extracts than hypocotyl length.

Allelopathic Effect of Lotus and Arrowhead Weed on Wheat, Wild Oat and Milkthistle Germination

“…Therefore, the root weight of all test species was affected up to a certain level. Lower root weight and root inhibition led to reduced water and nutrient uptake and consequently lower protein synthesis, respiration, cell division and thickness of seminal roots as well as delayed growth (Jafariehyazdi and Javidfar, 2011). These findings are in line with the results of (Mishra, 2015) who reported that aquatic weed extracts limited plant seed germination and root biomass and its elongation as well as some other metabolic activities of the test species.…”

Mycorrhiza‐mediated interference between cover crop and weed in organic winter cereal agroecosystems: The mycorrhizal colonization intensity indicator

“…The plant host-fungi contact is a crucial moment between the partners in activating the AMF-plant symbiosis, being mediated by the ability of the host plant to exude the "branching factor," such as the strigolactones, molecules also responsible of the seed germination of parasitic weeds (Akiyama & Hayashi, 2006;García-Garrido, Lendzemo, Castellanos-Morales, Steinkellner, & Vierheilig, 2009;Martin et al, 2001). On the contrary, the AMF non-host plants theory is mainly based on the ability to exude infection-inhibiting factors by the non-host species, such as the glucosinolate compounds produced by the Brassicaceae (Afzal, Bajwa, & Javaid, 2000;Bajwa, Javaid, Tasneem, & Nasim, 1996;Jafariehyazdi & Javidfar, 2011;Javaid, 2008;Javaid & Riaz, 2008).…”

Effect of defatted oilseed meals applied as organic fertilizers on vegetable crop production and environmental impact

“…Brassicaceae oilseed meals represent a particular type of meals; despite the similar N and phosphorous (P) content with respect to sunflower, no genetically improved seeds contain glucosinolates (GLSs) that through enzymatic hydrolysis via myrosinase produce a series of biologically active compounds (mainly isothiocyanates) (Fahey et al, 2001) that have shown an effect in controlling weeds (Ascard and Jonasson, 1991;Vaughn and Berhow, 1998;Vaughn et al, 2006;Rice et al, 2007), insect pests (Elberson et al, 1996(Elberson et al, , 1997, nematodes (Walker, 1996;Lazzeri et al, 2009), and soilborn pathogens (Smolinska et al, 1997;Manici et al, 1997;Mazzola et al, 2001;Chung et al, 2002). On the other hand, some authors demonstrated also significant allelopathic effects on seedlings of crops seeded after soil incorporation of brassicaceous crops with high GLS content (Jafariehyazdi and Javidfar, 2011), whilst for transplant crops, such as field vegetables, only minor effects on plant growth are reported (Haramoto and Gallandt, 2004;Ackroyd and Ngouajio, 2011). In any case the biocidal activity was clearly related to GLSs-type and concentration Vaughn, 1999;Bending and Lincoln, 2000).…”