Reaction of some maize genotyhpes to infestation with the witch weed (Striga asiatica)

Abstract

A total of twenty four maize genotypes comprising nine inbreds, six open pollinated, four synthetic and five hybrids were tested for tolerance to artificial infestation of Striga asiatica using seeds of the pest as inoculum source. Yields varied directly with tolerance level and reduction in plant height was observed with increase in age of the maize plants between 8 and 10 weeks after planting in most of the genotypes. Although, stem girth was not significantly different under striga infestation, plant height and leaf-area at 8 - 10 weeks were significantly different in the infested maize plants. Striga emergence counts was significant with marked effect on yield, while Striga damage rating ranged between two and four in tolerant genotypes and between five to nine among susceptible ones. Two inbreds (EV8485-Y and EV8725-100-2) STR, one hybrid (9044-27-Y) and one synthetic (NEW STR-1-W) were found to be tolerant to Striga asiatica. The tolerant maize genotypes may be desirable for introduction to S. asiatica endemic regions of Southern Guinea Savanna.

Key words: Maize genotype; artificial infestation; Striga asiatica, tolerance level

Moor Journal of Agricultural Research Vol.4(2) 2003: 210-217