TITLE:
Effect of Cold-Mediated Pretreatment on Microspore Culture in Winter and Spring Wheat
AUTHORS:
Rituraj Khound, Meenakshi Santra, P. Stephen Baenziger, Dipak K. Santra
KEYWORDS:
Androgenesis; Doubled Haploid; Homozygosity; Biotechnology; Breeding
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.11,
November
18,
2013
ABSTRACT: Microspore culture of wheat generates completely
homozygous (doubled haploid) plants in a single generation thereby reducing the
time required for wheat variety development. Success of microspore culture in
spring wheat is relatively higher than that in winter wheat. Cold
mediated pretreatment was reported to improve response of microspore culture in
wheat. The objective of the study was to determine and compare the influence of
cold pretreatment on microspore culture in spring and winter wheat.
Three spring (“Chris”, “Express”, and “Macon”) and three winter (“Anton”, “Antelope”, and “Camelot”) wheat cultivars were
used. In cold pretreatment, excised anthers were incubated in solution B at 25°C-28°C for 4-5 days followed by cold treatment at 4°C for 5 days and were compared with the no-cold
pretreatment at 25°C-28°C for 4-5 days. Isolated
microspores were cultured in induction medium (MMS4) at 27°C-28°C for 25-30 days in
the dark. Embryos (1-2 mm size) were transferred to
regeneration medium (MMS5). Numbers of multicellular structures, transferable
embryos and green plants were counted and data were used for analysis of
variance using a generalized linear model. It was observed that cold
pretreatment increased multicellular structures, transferable embryos and green
plants in both spring and winter wheat. However, the degree of improvement was
higher in spring wheat compared to winter wheat. The cultivars within spring
and winter wheat responded differently. Development of embryos from pro-embryos
was 4-5 folds lower in winter wheat than that in spring wheat, indicating
requirement of a possibly different hormonal composition in induction medium
for improving embryo induction in winter wheat. This report may provide future
direction of research to improve microspore culture response in winter wheat.