Comparison of interconnections between barley breeding material traits under organic and conventional growing conditions

Summary

While breeding for organic farming it is necessary to identify the most appropriate growing
conditions in which to perform the selection process. Soil fertility, crop management, yield level
and other factors may vary very much between each organic farm, and between organic farms and
research institutions where the selection is usually performed. Since plant breeding requires
considerable input of resources and the market for organic varieties is limited, it is essential to find
the most appropriate selection conditions that will provide acceptable varieties for organic farms.
Spring barley breeding lines selected from two cross combinations (Primus/Idumeja and
Anni/Dziugiai) at two distinctive organic and two conventional locations were used in the study.
The organic location 1 was situated in a research field of the plant breeding institute (with green
manure as fertilizer), the organic location 2 included an organic farmer’s field (with stable manure
as fertilizer), the conventional location 1 was located in a barley breeding field (with medium level
of mineral fertilizer input) and the conventional location 2 in a seed production field of the
institute (with high mineral fertilizer input). Selection of the breeding lines was done under the
respective growing conditions starting from F3 generation. Most appropriate lines for growing in
organic farming were selected at all 4 environments. Selected breeding lines were evaluated in F5
(n=20-23 per cross combination, without replications) and F6 generations (n=10 per cross
combination, 3 replications). Correlations between barley traits and the environments and cross
combinations will be compared in the presentation. The analysis of the correlation between grain
yield and observed plant traits of F5 lines indicated that tendencies between the lines obtained
from both cross combinations as well as between the environments were dissimilar in most of the
cases. Soil shading (evaluated at early stem elongation stage) correlated positively with grain yield
in all cases; the correlation was always significant for lines from the cross Primus/Idumeja, but
only at the conventional location 2 for Anni/Dziugiai lines (p<0.05). A significant positive
correlation between grain yield and plant development speed at tillering stage as well as between
yield and plant height at the beginning of stem elongation was found for Primus/Idumeja lines at
both organic locations and at the conventional location 1 (p<0.05). Plant height before harvest
did not correlate significantly with yield under organic conditions which is in contradiction with
some other studies. There was a tendency for planophyle growth habit to correlate positively with
yield under organic and conventional conditions for lines from both cross combinations. The
analysis of correlation of the F6 lines will be included in the presentation. This study was
performed with financial support of EEA grant EEZ08AP-27and European Social Fund co-financed
project 2009/0218/1DP/1.1.1.2.0/09/APIA/VIAA/099.