Seed Populations of Striga Species in Nigeria. G. L. Hartman, Former Research Associate, International Institute of Tropical Agriculture, Oyo Road, Ibadan, Nigeria. O. A. Tanimonure, Research Assistant, International Institute of Tropical Agriculture, Oyo Road, Ibadan, Nigeria. Plant Dis. 75:494-496. Accepted for publication 30 October 1990. Copyright 1991 The American Phytopathological Society. DOI: 10.1094/PD-75-0494.

Seeds of Striga asiatica, S. gesnerioides, and S. hermonthica were separated from soil with a 2.5 M sucrose flotation solution and 250- and 150-µm mesh screens. In 34 fields, the average and range of seeds·100 g^–1 of soil were 8.2 and 0–75, respectively. Seeds were recovered from 28 of the 34 fields sampled. Eighteen, six, and four fields had 1–5, 6–20, and > 21 seeds·100 g^–1 of soil, respectively. The maximum number of seeds·100 g^–1 of soil was 202, collected from one sample site in a field. Emerged S. asiatica, S. gesnerioides, and S. hermonthica were counted from 28 fields, and neither seeds nor plants of Striga were counted in two fields. The average number of seeds per plant produced by S. gesnerioides was 6.4 × 10⁴, and the average number of seeds per capsule was 604. Seed recovery and plant emergence were correlated (r = 0.79) at one site where 29 4 × 10 m plots were assessed.