Morphological and RAPD variability among Malaysian ecotypes of barnyard grass (Echinochloa crus-galli var. crus-galli (L) P.Beauv.)

Abdul Shukor JuraimiA, Arifin TasrifA, Jugah KadirA, Soetikno Slamet SastroutomoB andSuhaimi NapisC

A Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.

B CAB International, SE Asia Regional Centre, 43400 Serdang, Selangor, Malaysia.

C Faculty of Biotechnology and Science of Biomolecular, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.


Summary

An experiment was conducted to evaluate the variability of barnyard grassecotypes(Echinochloa crus-galli var. crus-galli) collected thought Peninsular Malaysia. Barnyard grass seeds were collected from 11 locations namely Perlis, Kedah, Penang, Perak, Kelantan, Terengganu, Pahang, Selangor, Negeri Sembilan, Melaka and Johor. Seeds were collected from five rice fields in each location. The distance between fields in each location sites was about 10 km. Seeds were grown in a glasshouse to maturity. Two methods were used to evaluate the variability of barnyard grass, namely morphology and RAPD analysis. For the morphological study, twelve traits (plant height, plant type, panicle length, panicle awn, flag leaf length, panicle width, culm diameter, spikelet length, spikelet width, spikelet weight, glume length and number of tillers) were analyzed, while four primers (A 07, A 20, OPG 06 and OPE 12) were selected for RAPD analysis.

The results showed that variability in morphological characteristics among ecotypes had been observed. These ecotypes were classified into six groups. Twenty-one ecotypes were found in group 1, while groups 2, 3, 4, 5 and 6 consisted of 2, 14, 14, 3 and 1 ecotypes respectively. The four RAPD primers produced five hundred and thirty three bands resulting in 87% polymorphic bands. Four groups were classified based on Jaccard's similarity. Groups 1 and 2 consisted of 11 and 12 ecotypes, respectively. Groups 3 and 4 had two and one ecotypes, respectively. Some ecotypes were closely related by morphological and RAPD analysis, while others were inconsistent. The variability of barnyard grass ecotypes might be due to adaptability to the geographic locations and weed management practices. These ecotype populations could be an important source of variability, and they may respond differently to chemical or to biological control.

Key words: ecotypes, morphological, RAPD, barnyard grass, Malaysia.

 

Plant Protection Quarterly (2005) 20 (2) 52-57.