4.2 Infection of T. laevis and T. controversa in
anther cells
The common, dwarf, and other related bunt fungi have a long infection
and development process from seedling to grain filling (Lu et al., 2015;
Nguyen et al., 2019; Bokore et al., 2019). In fact, the mycelium that
develops in the infected seedling remains spares until a massive
proliferation in floral tissue (Ghareeb et al., 2011). In the present
study, we inoculated wheat spikes with mycelia of T. laevis andT. controversa to study the effects of infection on the
development of wheat anthers. We tracked the prevalence of T.
laevis or T. controversa mycelia into somatic and reproductive
anther cells for understanding the process of infection. Hyphae
proliferate finally into the pollen grains and releasing of these
infected pollens for pollination, is critical for normal plant
reproduction and produced seeds is transformed into a generally
spherical sorus termed a bunt ball that contains dark-colored mass of
teliospores (Goates & Peterson, 1993). Our results showed that hyphae
of T. laevis was well established on EPI cells at 800 µm long and
rupture the cell structure (Figure 4A-C ). EPI cells are the
most earliest infected anther cells from filaments, from which the
hyphae spread to other connective cells. Thus, the nearest next cell of
EPI is EN, which was infected at 1220 µm long anther. Similarly, TA and
PG cells were infected at 1300 µm and 1520 µm. By comparison with
control anthers, TA should be disappeared at 1300 µm, but which was
visible at 1300 µm (Figure 4G-I). We conclude that the pathogen
prevents normal development of TA and PG which interrupts the production
of signals that results in the development of reproductive cells (Walbot
& Skibbe, 2010; Li, 2013). The mechanism of T. controversainfection was similar to that of T. laevis , but delayed
differentiation in TA and PG compared to control. TA was observed at
2100 µm and PG was also present on the 2100 µm long anthers (Figure6G-I ) (Hu et al., 2002; Schirawski et al., 2007).