Allelopathic effects of bindweed (Convolvulus Arvensis L.)‎ root exudates on plants and soil microflora

الملخص EN

One of the main weeds ways to release allelochemicals is root exudation, which is an important regulating agent in neighbor plants and microbes.

The rhizosphere microbial communities were clearly rich, compared with non rhizosphere soil at both high and low density areas of filed bindweeds (Convolvulus arvensis L.).

Bindweed roots exudates inhibited rhizosphere soil bacteria and fungi in high density sites than the low density ones.

The EC50 of bindweed ethyl acetate root exudates extract was 1625 (Lactuca sativa L.) and 1360 μg/g (Phalaris paradoxa L.) for seedlings biomass fresh weights.

The amount of total phenolics was higher in rhizosphere than non rhizosphere soil that ranged between 0.7 to 0.9 and 0.3 to 0.57 mg/g soil, respectively.

The analysis of exudates profile has shown six compounds, namely umbelliferone (C9H6O3), quercetin (C15H10O7), gentisic acid glycoside (C13H16O9), coumaric acid glycoside (C15H18O8), vanillic glycoside (C14H18O9) and ferulic glycoside (C16H20O9), characterized by LC–MS.

These results support the aggressiveness of bindweed in different types of soil through its suppressive effects upon associated plants and microbes through release of underground chemical signals