TITLE:
Developmental Dynamics of Wheat (Triticum aestivum L.) Microspores under Culture
AUTHORS:
Ming Y. Zheng, Kiersten Bieren, Roland Griggs
KEYWORDS:
Microspore Culture, Embryogenic Abortion, Doubled Haploids, Triticum aestivum L.
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.6 No.12,
December
14,
2015
ABSTRACT: Doubled haploid production via microspore culture is a technique known to accelerate crop
breeding by shortening the breeding cycle through achieving homozygosity in one generation.
Prior research observed that some embryogenic microspores aborted their development before
reaching the embryoid stage. Such embryogenic abortion reduces embryoid yield, making microspore
cultures less efficient. The present research aims at identifying stages during which microspore
development is susceptible to embryogenic abortion. Information gained through delineation
of the developmental dynamics of microspores in culture could be used to improve the efficiency
of microspore culture. Embryogenic microspores were isolated from stress-treated wheat
(Triticum aestivum L.) tillers and cultured in liquid medium. The development of embryogenic
microspores was monitored over a 35 day period. At day 7, 10, 14, 21, 28, and 35, the developing
microspores were counted and categorized into multicellular structures, pre-embryoids, immature
embryoids and mature embryoids. The results showed that 44% - 62% of embryogenic microspores
halted their development before the mature embryoid stage. Of these aborted embryogenic
microspores, 21% - 33% terminated as multicellular structures, 16% - 19% arrested their
development as pre-embryoids, and 7% - 10% halted development as immature embryoids. Identifying
factors that are responsible for embryogenic abortion and finding remedy to the issue will
help improve the efficiency of doubled haploid production.