Comparative growth studies of glyphosate-resistant and susceptible Eleusine indica (L.) Gaertn. (goosegrass) biotypes from the Malaysian Peninsular
J.L. Chong, R. Wickneswari, B.S. Ismail and S. Salmijah, School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, University Kebangsaan Malaysia, 43600 UKM, Bangi, Malaysia.
A comparative study of four putative glyphosate-resistant (R) and four glyphosate-susceptible (S) biotypes of Eleusine indica (L.) Gaertn from four locations in the Malaysian Peninsular namely Bidor, Chaah, Lenggeng, and Temerloh was conducted under non-competitive conditions over a 10 week period to determine the relative competitive fitness of the resistant and susceptible biotypes. The test characteristics compared included growth habit, plant height, number of tillers, above ground dry weight, number of inflorescences and dry weight of the inflorescences (reproductive weight).
The R and S biotypes exhibited no distinct differences among populations or within biotypes except the S biotype from Temerloh which had a prostrate growth habit compared to the others which had an erect growth habit. There were significant differences (P = 0.05) in plant height at week 2, 6 and 8 between the biotypes. The R biotypes showed an increase in height but there were no significant differences in plant height within the R biotype populations. However, there were significant differences in height within the S biotype populations at nearly every harvest date. As for the number of inflorescences and reproductive weight, the R biotype produced a higher number of inflorescences at week 10 and could have shown a high reproductive weight if the shedding of seeds did not occur around that time.
Plant Protection Quarterly (2008) 23 (2) 99-103.