Rice is propagated mainly by using saved seeds in Nigeria. Most farmers save part of their harvest as planting materials for the subsequent season, thus necessitating storage. However, storage sometimes affects seed vigor as shown by the amount and speed of seedling emergence in the field. Thus, it is important to know whether or not differences occur among rice varieties for seed vigor. The existence of such differences among varieties indicates the possibility of improving the longevity of rice in storage.
We studied 50 randomly selected lowland rice genotypes during the 1999 cropping season at the University Experiment Research Station (UERS) to investigate whether or not differences occurred in seed vigor. The experiment was laid out in a randomized complete block design with four replications. One hundred seeds of each genotype were planted in 5-m-long single-row plots. Interrow spacing was 0.30 m, with an intrarow spacing of 0.10 m and two seeds hill-1. For each plot, the number of seeds that emerged was counted daily starting from the third day after planting (DAP) until there was no further emergence.