Relationship of Sprangletop (Leptochloa chinensis (L.) Nees) morphology and weeds diversity in Rice fields, Tumbon Ongkarak sub-district, in Onkarak district, Nakornnayok Province Thailand

Abstract

A field survey of weeds found in rice so that the rice grains start. Weeds are found Sprangletop (Leptochloa chinensis Nees)Banyard grass (Chinochloa crus-galli (L.) T. Beauv.) Goose weed (Sphenoclea zeylanica Gaertn) and small flower (Cyperus difformis L) , and Spangelop were found all paddyfield . The diversity index of weed showed that P3 contained highest weed diversity with shannon index equal to 1.149 and followed by P4, P7, P2, P6, P1 and P5 with the index equal to1.039, 0.995, 0.995, 0.959, 0.933 and 0.598, respectively.The morphorlogy comparision showed that the stem height, leaves width and roots length are found in natural populations with rice were clearly different the paddy field. The stem height, leaf width of the weed in natural habitat were more than the paddyfield group. While, the root length of the field was more than groups in nature. The correlationship of the Spangelop morphology in paddyfield population showed the length of stem and root correlated with 99% and associated with a bouquet at 95%, the stem height relative root length at 95 %. However, the difference morphology of spangelop cloud be used as biomarker to track weed distribution in paddy fields