Aboveground phytomass productivity and morphological variability of Tunisian accessions of Cenchrus ciliaris L.

Abstract

This study assessed the aboveground aerial phytomass produced by 47
accessions of Cenchrus ciliaris L. locally collected in the
arid zone of Tunisia and classified into six eco-geographic groups. The extent
of genetic variation in five morphologic parameters was examined. Correlations
among all parameters were also analysed. For three years, phytomass of these
accessions was cut and measured for three cutting periods characterised by
different rainfall features. In 1998 the mean of the phytomass productivity was
199.1g DM (dry matter) plant^–1. The
productivity in 1999 was 81.0g DM plant^–1, but in 2000 the
productivity was only 21.6g DM plant^–1. Positive correlations were
found between dry matter and all morphological parameters, especially tuft
diameter (r = 0.670) and tuft height (r = 0.637). Principal components analysis
was carried out on all variables. For both dry matter and phenology,
individuals differentiated strongly, but irrespective of their accession or
eco-geographic origin.

Keywords: arid zones, buffelgrass, grassland, Tunisia

African Journal of Range & Forage Science 2004, 21(1):
49–55