HYBRID HAPLOID TREES. “In this study, we investigated the induction of haploid plants in ‘Hirado Buntan’ pummlo (Citrus grandis) through in-situ gynogenesis by pollination with irradiated pollens of trifoliate orange (255, 325 and 500 Gy) and ‘Tongshui 72-1 Jincheng’ sweet orange (255, 395 and 500 Gy).”
http://www.sciencedirect.com/science/article/pii/S0304423816302710