Grain yield, spikes per unit area and weight per
kernel in straw and concrete mulch treatments were
significantly higher than those in control and straw
mulch treatments in both years (Table 2). However,
there was no significant difference in kernels per
spike among the four treatments. Spikes per unit area
in film mulch treatment were significantly greater
than those in concrete mulch treatment for 2002~2003,
but the results were not similar for year 2003~2004.
However, the differences between the two treatments
were not significant. Tiller’s initiation of winter
wheat occupies a long period which is divided into
two stages, before winter and in the next spring. The
tillers before winter are called winter-stems (main
stem included) and the tillers initiation peaked in the
next spring which was max-stems (main stem included).