Soil shading by qingqinglxkc


									     Comparison of interconnections between barley breeding material traits under organic and conventional
                                                                                                                                                                                                                                                                                                      growing conditions
                                                                                                                                                                                    Legzdina, 1A. Kokare , 1I.Beinarovica and 2E.T. Lammerts van Bueren
                                                                                                                                                                                             1 State Priekuli Plant Breeding Institute, Latvia

                                                                                                                                                                                 2Wageningen UR Plantbreeding, Wageningen University, The Netherlands

 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. Defining the most suitable
 selection environments was pointed out among the key questions for development of breeding strategies for organic farming (Wolfe et al., 2008).
 The aim of this study was to find out if there are different tendencies in correlations between the traits under different organic and conventional conditions.

 Material and methods
 Spring barley breeding lines selected from two cross combinations
 (Primus/Idumeja and Anni/Dziugiai) at two distinctive organic and two
 conventional locations (Table 1) were used in the study. ‘Primus’ is late
 maturing, old Swedish variety with very tall plants. It was crossed with
 recently released, early maturing Latvian variety ‘Idumeja’ with medium tall
 plants. In the second cross the short straw Estonian variety ‘Anni’ (developed
 in 1990-ties) with good yields under various growing conditions was crossed
 with the Lithuanian variety ‘Dziugiai’ from the middle of last century, with quite
 tall plants, poor lodging resistance, but with a rapid early development.
 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 for traits essential for organic farming in F5 and F6
 generations and in F7 comparison of selected lines was done in all four                                                                                                                                                                                                                                                                                                           Figure 1. Scheme of the breeding experiment, Priekuli 2006-2010.
 environments (fig. 1). Phenotypic correlations between barley traits were
                                                                                                                                                                                                                                                                                                                                                                 Table1. Description of crop management systems at two organic and two conventional trial
                                                                                                                                                                                                                                                                                                                                                                                             locations in Priekuli, 2006 – 2010.
                                                                                  Soil shading ability                                                                                                                                                             Plant development speed
                            C2                                                     *
                                                                                                                                                                                                                                 C2                                                                                                                                                                           Fertility management                   Management of
                                                                                                                                                                                                  Primus/Idumeja Anni/Dziugiai

                            C1                                                                                                                                                                                                   C1                                                                                                                         Location           Pre-crop                                                          Diseases,
                           O2                                                         **                                                                                                                                                                                                        **                                                                                            Amount of N                 Type (amount)            pests        Weeds
                                                                                                                                                                                                                                 O2                                                            **
                           O1                                                                         **                                                                                                                         O1                                                                                                                   Organic 1             Green manure    N 26.5 kg ha            Rapeseed or peas for        No            harrowing
                                                                                                                                                                                                                                                                                                                                  2010                                                                                                    -1
                                                                                                                                                                                                                                                                                                                                                      (O1)                  crop                                    green manure (~20 t ha )

                            C2                                                                                                                                                                                                   C2
                                                                                                 *                                                                                                                                                                                                                                                    organic trial field
                            C1                                                                                                                                                                                                   C1                                                                               **              2008                                                                   -1
                                                                                                                                         **                                                                                                                                                                             **                            Organic 2             Perennial       N 41 kg ha              Stable manure (cows) (~40   No            No
                           O2                                                                        **              **                                                                                                          O2                                                            **
                                                                                                                                                                                                                                                                                                                 **                                   (O2)                  grasses or                              t ha )
                                                                                             ** **                                                                                                                                                                              *                                                                     organic farm          cereals
                                                                                                                                              **                                                                                 O1                                                                   **                                                                                                 -1
                                                                                                                                                                                                                                                                                                                                                      Conventional 1 (C1)   Potatoes        N 80 kg ha              Inorganic                   Insecticide   Herbicide
   -0.2                                   0                             0.2           0.4                    0.6                     0.8                                1          -0.4          -0.2                                             0                     0.2           0.4                 0.6          0.8    1                       breeding field                                                                            if needed
                                           Plant height in beginning of stem elongation                                                                                                                                                                                                                                                                                                                 -1
                                                                                                                                                                                                                                                       Plant height before harvest                                                                    Conventional 2 (C2)   Potatoes        120 kg ha               Inorganic                   Insecticide   Herbicide
                                                                        C2                                                                                                                                                                                                                                                                            Seed production                                                                           if needed


                                                                        C1                                                                                                                                                                                                                     **
                                                                        O2                                                                                                                                                                             O2
                                                                        O1                                                                                                                                                                             O1                                                                                The analysis of the correlation between grain yield and observed plant traits indicated that tendencies
                                                                                                                                                                                                                                                                                                                                         for the lines obtained from both cross combinations as well as between the locations and testing years


                                                                        C2                                                                                                                                                                              C2                                                       **
                                                                                                                               **                                                                                                                                                                          **
                                                                                                                                                                                                                                                                                                                                         were dissimilar in most of the cases.
                                                                        C1                                                                                                                                                                              C1
                                                                                                                                    **                                                                                                                                                                                                    Soil shading correlated positively with grain yield in most of the cases (fig.2), but the correlation was
                                                                        O2                                                **                                                                                                                           O2                                                                                significant in all years only for lines selected from cross Primus/Idumeja in O1 location. On the whole
                                                                                                                                                                                                                                                                                                                                         higher correlation coefficients were found for Primus/Idumeja lines and in organic locations, which can be
                                                                                                                                                                                                                                                                                                                                         explained by higher competitive ability with weeds.
   -0.6                    -0.4                    -0.2                       0       0.2                 0.4              0.6            0.8                           1          -0.6         -0.4                             -0.2                               0          0.2            0.4           0.6         0.8   1
                                                                                                                                                                                                                                                                                                                                         Plant development speed (scored in tillering) correlated with yield significantly positive for
                                                                                    TGW                                                                                                                                                                                       Protein                                                    Primus/Idumeja lines in most of the cases in both organic and also C1 locations. For lines selected from
                                                                                                     **                                                                                                              *                                             C2                                                                    cross Anni/Dziugiai this correlation was positive only in O2 location, but also negative tendencies were

                                                                                                                                                                                                                                                                   C1                                                                    found.
                                                                                                                                                                                                                                                                                                                                         On the whole, higher positive correlations between plant height (measured in stem elongation and before
                                                  O2                                                                                                                                                                                                                                                                                     harvest) and yield were stated in organic locations and for lines derived from cross Primus/Idumeja. Plant
                                                                                                            **                                                                                                                                                     O1                                                                    height in stem elongation for Anni/Dziugiai lines in 2010 correlated significantly positive in O2 location,
                                                                                                                **                                                                                        **
                                                                                                                                                                                                                                                                   C2                                                                    however, in the same year it was significantly negative in C2 location.


                                                                                                **                                                                                                                                                                 C1
                                                                                                                                                                                                                                                                                                                                          Unusual tendencies were found for correlations between grain protein content and yield under organic
                                                  O2                                                                                                                                        **                                                                     O2                                                                    conditions: for Anni/Dziugiai lines there were no negative correlations (2009-2010) and for Primus/Idumeja
                                                  O1                                       **                                                                                                                                                                      O1
                                                                                                                                                                                                                                                                                                      **                                 lines the correlation was even significantly positive in 2010. On the contrary, correlation coefficients
                                                                                                                                                                                                                                                                                                                                         between yield and grain starch content were positive and on the whole higher in conventional locations.
   -0.4                     -0.2                         0                    0.2          0.4             0.6                 0.8                 1                             -0.8     -0.6                             -0.4                   -0.2                  0           0.2        0.4              0.6     0.8   1
                                                                                                                                                                                                                                                                                                                                         TGW correlated positively with yield in 2010 only and in all locations except O2.
          Figure 2. Coefficients of correlation between grain yield and traits of lines selected from two cross combinations in two
             organic and two conventional locations in the years 2008-2010 (*, ** significant at the 0.05 and 0.01 level, respectively).                                                                                                                                                                                                 Soil shading correlated positively with leaf position and plant development speed in majority of the
                                                                                                                                                                                                                                                                                                                                         cases in organic and in conventional locations (data not shown). Regarding plant height, significant
                                                                                                                                     Soil shading / plant growth habit                                                                                                                                                                   positive correlations with soil shading were found in more cases if it was measured in stem elongation if
                                                                                                                                                                                                                                                                                                                                         compared to measurement in maturity.

                                                                                                                                                                                                                                                                                                                                         The results of this study does not approve the usefulness of leaf length and width measurements for
                                                                                                     **                                                                 C1                                                                                                                                                               selection purposes: no significant positive correlations with soil shading ability were found for both
                                                                                                                      *                                                 O2                                                                                                                                                               measurements under organic conditions. However, in two cases leaf length correlated positively with grain
                                                                                                                                                                                                                                                                                2010                                                     yield.
                                                                                                     **                                                                                                                                                                                                                                  Correlations between soil shading and lodging were mostly negative indicating that genotypes with better

                                                                                                                                                                        C2                                                                                                                                                               soil shading ability are less resistant to lodging. This fact might cause a problem under organic conditions
                                                                                                                                                                        C1                                                                                                                                                               with higher fertilization level.
                                                                                                                                                                        O2                                                                                                                                                               Dissimilar tendencies in correlations between soil shading and plant growth habit for lines from both cross
                                                                                                                                                                                                                                                                                                                                         combinations are shown in Figure 3. For Anni/Dziugiai lines most of correlations are negative indicating
                                                                                                                                                                                                                                                                                                                                         that soil shading was better for lines with erect growth habit, while for other cross combination lines with
                                                                                    -0.8              -0.6                 -0.4               -0.2                           0            0.2                                    0.4                                 0.6                                                                 more planophyle growth habit provided better shading. It can be explained by strong and significantly
                                                                         Figure 3. Coefficients of correlation between soil shading and plant growth habit                                                                                                                                                                               negative correlation between planophyle growth habit and plant development speed which was found for
                                                                         of lines selected from two cross combinations in two organic and two conventional                                                                                                                                                                               Anni/Dziugiai lines in majority of the cases.
                                                                         locations in the years 2008-2010 (*, ** significant at the 0.05 and 0.01 level, respectively).

      •In the selection process it has to be considered, that the tendencies of correlative connections may differ between the cross combinations. Differences between the years suggest that meteorological
      conditions can influence correlative connections between the traits.
      •Positive correlations between grain yield and soil shading ability gives a possibility to select lines with good yield and good competitive ability with weeds at the same time; higher correlation coefficients
      under organic conditions approve the positive effect of better ability to compete with weeds.
      •Plant development speed can be positively related with grain yield, especially under organic and lower input conditions, but not under high input conventional conditions.
      •The interconnection between grain yield and protein content might be not negative under organic conditions in contrary to conventional conditions.
      •Essential traits for assessment of competitive ability with weeds according to correlations with soil shading are plant development speed, leaf position and plant height in beginning of stem elongation stage.

Wolfe MS, Baresel JP, Desclaux D, Goldringer I, Hoad S, Kovacs G, Löschenberger                                                                                                                                                                                    Acknowledgements
F, Miedaner T, Østergård H, Lammerts van Bueren ET (2008) Developments in                                                                                                                                                                                          This study was performed with financial support of EEA grant EEZ08AP-27 and European
breeding cereals for organic agriculture. Euphytica, 163: 323-346.                                                                                                                                                                                                 Social Fund co-financed project 2009/0218/1DP/

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