Figure 3 Intraspecific variation coefficients in root system
architecture traits of 47 annual ephemerals in the desert of northern
Xinjiang, China.
3.2. Phylogenetic signal
of root system architecture traits
Phylogenetic signal is also important ecological indicator for detecting
the impact of phylogenetic relationship between species on traits. We
constructed a phylogenetic tree of annual ephemerals in this study based
on the APG IV (Angiosperm Phylogeny Group) plant classification system
(Fig. 4). Blomberg’s K values for six root system architecture
traits were immediately detected (Table 2). The results showed that theK value of MRD was 0.409, showing a significantly and weakly
phylogenetic signal (0<K<1, P<0.05).
However, no significantly phylogenetic signals were detected for the
other five root system architecture traits (K<1;
P>0.05).