2.6 Data analysis
Data were presented as means ± standard error (SE) from four
replications for each experiment and determination. The data were
analyzed by full factorial ANOVAs followed by Tukey’s honestly
significantly different (HSD) tests. Weed inhibition and allelochemical
production were calculated as (1-T/C)×100, based on weed dry weights or
allelochemical quantity in treatments (T) and in controls (C).
Horizontal asymmetry in root length and biomass were calculated as
response ratios Vn/Va (Yang & Kong, 2017). Vn is the response value for
rice-weed interactions while Va is the response value for rice or weed
alone. Vn/Va >1 represented root growth increased towards
neighbors,
resulting an intrusive pattern of root placement. Vn/Va<1
represented root growth decreased towards their neighbors and Vn/Va=1
represented an unaltered pattern of root growth. Principal component
analysis (PCA) of PFLA data was performed with the STATISTICA software
package, version 6.0 (StatSoft Inc., USA). Data were transformed using
sample unit totals to represent the relative abundance of each PLFA
(mole percentage of total PLFA). All data analyses were conducted with
SPSS 25.0.
3
RESULTS