title: Recent advances in anther culture of Hevea brasiliensis (Muell.-Arg.).
abstract: The yield of pollen embryoids from cultured Hevea anthers was increased 4 fold by optimizing the proportion of ammonium nitrate to potassium nitrate in the dedifferentiation medium. For optimal differentiation of pollen embryoids, kinetin, 2,4-D and α-naphtalene acetic acid are required. Anther culture for 50 days on the dedifferentiation medium is a prerequisite for the selective development of calli and embryoids from microspores.The determination of chromosome numbers in embryoids, plantlets and regenerated trees reveals that they originate from (poly)haploid pollen grains (n=2x=18). Aneuploid, triploid (3x=27) and tetraploid (4x=36) cells were encountered in increasing frequencies as the embryoids and plants developed. A few haploid cells with 9 chromosomes were consistently observed. Buds from shoots with mixoploid chromosome numbers can be grafted and the change in the chromosome constitution of the developing new shoots followed.
authors.affiliation: Institute of Genetics, Academia Sinica, Beijing, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Chen
authors.forename: C
authors.initials: C
authors.lastname: Qian
authors.forename: M
authors.initials: M
authors.lastname: Qin
authors.forename: X
authors.initials: X
authors.lastname: Xu
authors.forename: Y
authors.initials: Y
authors.lastname: Xiao