Allelopathic effects of different concentration root exudates of Kochia scoparia on oil flax seed germination

Allelopathic effects of different concentration root exudates of Kochia scoparia on oil flax seed germination were studied by using methods of bioassay. The results showed that: 1) different concentrations of K.scoparia root exudates had different degrees of inhibition (or promotion ) on germination energy, germination rate, germination index and vigor index of oil flax seeds, while the inhibition rate increased with the treatment concentration rising. 2) Different concentrations of K.scoparia root exudates showed to promote the root length of oil flax seedlings and inhibit the shoot height, root fresh weight and shoot fresh weight. However, whether it is promotion or inhibition, the effects trended to be increased with the increase of concentration; but there was no significant difference between the treatments and the control. All these results showed that the root system secretion was one of the way in which K.scoparia could release allelochemicals and affect plant growth around them.3) The reason of K.scoparia root exudates affecting flax seed germination was mainly due to inhibit the seed vigor index; and affecting flax seedling growth was largely due to made roots becoming thin and long.