Classification of Itchgrass Using Morphological Traits and AFLP Techniques

Abstract

Classification of itchgrass (Rottboellia cochinchinensis) using morphological traits and AFLP techniques was conducted in the Department of Agronomy, Faculty of Agriculture at Kamphaeng Saen, and DNA Technology Laboratory, BIOTEC at Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom province during October, 2007 – December, 2008. Itchgrass was collected from 3 sites of a farmer’s field in Jae Hom district, Lampang province, the experiment field at the Department of Agronomy, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom province, and the experiment field at National Corn and Sorghum Research Centre, Pak Chong district, Nakhon Ratchasima province. Then morphological traits of itchgrass were observed. The results indicated that itchgrass from the farmer’s field in Jae Hom district, had some morphological traits was different from at the experiment field at the Department of Agronomy, Kasetsart University, Kamphaeng Saen Campus, and from the experiment field at National Corn and Sorghum Research Centre, Pak Chong district. The colour of leaf blade, leaf sheath, stem and root of itchgrass from the farmer’s field in Jae Hom district was darker and its trichomes were softer than in the other 2 sites. In addition, analysis of the genetic relationship of itchgrass using AFLP was investigated. The results indicated that itchgrass can be divided into 2 groups. The first group consists of itchgrass from the experiment field at National Corn and Sorghum Research Centre district, Nakhon Ratchasima and from the experiment field at the Department of Agronomy, Kasetsart University, Kamphaeng Saen Campus. The second group is itchgrass from the farmer’s field in Jae Hom district. It was apparent that the similarity index in the first group was 0.98, whereas in the second group it was 0.23. It is suggested that classification of itchgrass using morphological traits has a relationship with analysis of the genetic relationship of itchgrass using AFLP. This can be used to assess the genetic diversity of itchgrass.