Natural cross-pollination in roselle, Hibiscus sabdariffa L. (Malvaceae)

Two local varieties of roselle (Hibiscus sabdariffa L.), Jamaican Green and Jamaican Red, were grown to determine the amount of natural cross-pollination. Two planting arrangements (alternating rows; alternating individuals in a row) and two planting dates, a month apart, were used for the outcrossing experiments. Stem pigmentation, red (R-) vs. green (rr), was used as a genetic marker in the estimation of outcrossing. Homozygous dominant and recessive genotypes of Jamaican Red and Jamaican Green, respectively, were grown in both of the planting arrangements and dates. Seeds from open-pollinated capsules of randomly selected Jamaican Green plants were planted to score the frequency of cross-pollination. Estimates of natural cross-pollination ranged from 0.20 +/- 0.09% to 0.68 +/- 0.34%. Roselle outcrosses at a low rate in Jamaica.