鳢肠水提液对棉花和棉田常见杂草的化感作用

采用培养皿滤纸法研究鳢肠水提液对棉花和棉田常见杂草种子萌发和幼苗生长的化感作用。结果表明:当鳢肠水提液质量浓度为0.01~0.08 g·m L-1时,对中棉所49和中棉所79种子萌发影响不大,而对杂草种子的萌发表现为抑制作用;其中,对禾本科杂草种子萌发的抑制强度表现为牛筋草马唐稗草,对阔叶杂草种子萌发的抑制强度表现为反枝苋马齿苋苘麻。鳢肠水提液对棉花和杂草幼苗生长的影响表现为,低浓度促进,高浓度抑制,并随着质量浓度增加抑制作用提高,其中0.04~0.08 g·m L-1的鳢肠水提液对反枝苋胚根和胚芽长的抑制率均达到100%。

Allelopathic Effect of Aqueous Extracts of Eclipta prostrata L. on Cotton and Common Weeds in Cotton Field

This study was conducted to investigate the allelopathic effect of aqueous extracts of Eclipta prostrata L. on seed germination and seedling growth of cotton and six weed species in cotton field using Petri dishes. The results showed that aqueous extracts of Eclipta prostrata L. at concentrations from 0.01 to 0.08 g·mL^－1 strongly inhibited the germination of weed species, but only slightly inhibited those of CRRI 49 and CRRI 79. For different grass weeds, its inhibition effects to seed germination represented as Eleusine indica (L.) Gaertn. ＞Digitaria sanguinalis (L.) Scop. ＞Echinochloa crusgalli (L.) Beauv. For different broadleaf weeds, its inhibition effects to seed germination represented as Amaranthus retroflexus L. ＞Portulaca oleracea L. ＞Abutilon theophrasti Medic. The extracts stimulated growth of cotton and weed seedlings at lower concentrations, while inhibited their growth at higher concentrations, and inhibitory effects increased with the increasing concentration of the aqueous extract, with concentrations of 0.04―0.08 g·mL^－1 inhibiting radicle length and plumule length of A. retroflexus by 100%.