Introduction Material and Methods Results

Response of white clover (Trifolium repens) to different histories of arable management in a terminated long-term trial Thomas F. Döring, Sören Schultz, Sebastian Roye Department of Agronomy and Crop Science, Humboldt-Universität zu Berlin, Albrecht-Thaer-Weg 5, D-14195 Berlin E-mail: [email protected]

Introduction Background

 Long-term agricultural field trials (LTAEs): tool for assessing the  

sustainability of agricultural management options [1]. Usually, LTAEs characterized by static management, i.e. the different treatments remain unchanged over time. Current study: differentiated management consisting of 32 treatment combinations terminated after nine decades [2]; Then all plots treated equally.

  This allows studying after-effects of the different agronomic management histories on various plant and soil parameters; can be used to monitor natural recovery processes [2].

Research question

 How does white clover respond to the after-effects of different

Fig. 2: White clover in flower in one of the limed and manured plots (July 2015)

Results

 White clover cover increased over time: 0.05% in June 2014, 0.39% in September 2014 and 3.51% in June 2015.

 Frequency of white clover highest in plots with previous liming and 

historical management conditions?

FYM, lowest in plots without liming and without FYM (Fig. 3). The factors Rotation, Phosphorus and Depth of ploughing had much lower effects on white clover than Liming and FYM.

Material and Methods Microplots with T. repens (%)

100

Trial location and environmental conditions

 Location: Berlin (52° 28' N, 13° 18' E, 51 m asl)  Climate: temperature: 9.9°C, precipitation 562 mm (1981-2010)  Soil: Albic Luvisol, 72% sand, 0.7% SOC, pH 3.6 to 7.1 Trial set up and design

 Start of trial DIII: 1923; five trial factors up to 2013:     

Depth of ploughing (28 cm vs. 17 cm), -1 -1 Liming with CaCO3 (0.5 vs. 0 t ha a ), -1 -1 Fertilisation with farm yard manure (FYM) (15 vs. 0 t ha a ), Phosphorus addition (with vs. without), Crop rotation (two different four-course rotations).

Fig. 1: Long term trial DIII in Berlin Dahlem.

Investigations and data analysis

 Presence and percentage cover of white clover (Fig. 2) deter 

mined in all plots in June and September 2014 and in April and June 2015. Size of core plot: 3 × 4 m. Additionally, presence of white clover determined in July 2015 on 36 microplots of 0.5 x 0.5 m in each of the 96 plots. Because of trial design, data cannot be analyzed by ANOVA.

References

[1]Ellmer F, Baumecker M. 2005. Static nutrient depletion experiment Thyrow. Results after 65 experimental years. Archives of Agronomy and Soil Science 51:151–161. [2] Döring TF, Schweitzer K, Baumecker M, Ellmer. 2015. The new life of an old field trial. Aspects of Applied Biology 128: 35–36.

FYM-

FYM+

FYM-

Liming-

Fig. 3: Percentage of microplots with presence of white clover (mean ± SD), depending on management history; trial factors Liming and Farm yard manure application.

 Mapping of white clover: absence of edge effects, relatively homogenous spatial distribution within treatments (Fig. 4). Therefore probable source of clover: emergence from seed bank within the plots after termination of the herbicide regime.

with liming

 Grass mulched at ca. 5 cm height twice in 2014 and once in 2015.  No fertilisation or chemical weed control during 2014 or 2015.

20

Liming+

P1

P9

1 1 1 1 1 1

1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1

1 1

1

1

1 1 1 1 1

1 1 1 1 1 1

without

1 1

1

P2

P1

1 1 1 1 1 1

1 1 1 1 1

1 1 1 1 1

1 1

1

1 1 1

1 1

1 1

1

1

1 1 1 1 1 1

1 1 1 1 1 1

1

1 1 1 1 1

1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1

1 1

1 1

1 1

1 1 1 1

1 1 1

1 1

1 1

1 1 1 1

1

1 1 1 1

1 1 1

P 41

1

P 26

P 19

1 1 1

P 33

1 1 1 1 1 1

1 1 1 1 1

P 18

P 11

1

P 25

1 1 1 1 1 1

1

1 1

-Ca

P 17

1

P3

1 1

1 1 1

1

1

1 1 1 1

1 1 1 1 1 1

1 1 1

1

P 34

1 1 1 1

1 1 1

1 1

1

1 1 1 1

1 1 1 1

1

1

1 1

1

1 1 1 1

1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1

P 35

P 57

1 1 1 1 1

1 1

1

P 42

1 1 1 1 1

1

P 27

P 49

1

1 1 1 1 1

1 1 1 1 1

1 1 1 1

1 1 1 1 1 1

1 1 1 1 1

1 1 1 1 1

1 1 1 1 1 1

P5

1 1 1 1 1

1 1 1 1

1

1 1

1

1 1 1 1

1 1

P 43

P 51

1

1

P 12

P2

1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1

1 1

P 73

1 1 1

1 1 1 1

1 1

1 1

1 1 1 1 1

1 1

1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

P 36

P 44

1

1 1

1

1

1 1 1

P 89

1 1 1 1

1 1 1 1 1

1 1 1 1

1 1 1

1 1 1 1

1 1 1 1 1

1 1 1 1

P 75

1 1

1 1 1 1

P6

1 1 1 1

1 1 1 1 1 1

1 1 1 1

1 1 1 1

1 1 1 1

1 1 1 1 1

1

1 1 1

1 1 1

P9

1 1 1 1

1 1 1 1 1

1 1 1 1 1

1 1 1 1 1

1 1 1 1 1

1 1 1 1

P 83

1

P 91

1 1 1

1 1

1

P 52

1

P 82

1 1

P 67

1

1

P 28

1 1

P 74

1 1 1

1 1

P 81

1

P 66

1 1

P 59

1

1 1

P4

P 65

1 1 1 1

P 58

1

1 1 1

P 68

P 76

P 84

P 92

1 1 1

1 1

1 1

1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1

1 1

1 1

1

P5

P 13

with

1 1

1 1 1 1

1 1 1 1 1 1

P 21

1 1

1

1 1 1

1 1

1 1

1 1

P 29

1 1 1 1

1 1

1 1 1

1 1 1

1 1

1 1

1 1 1 1

1 1 1

P 37

1 1

1

1 1

1

1 1

1 1 1 1 1

1 1 1 1 1 1

1 1 1

P 45

1 1

1 1 1 1

1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1

1 1 1 1 1

1 1 1 1 1 1

P 53

P 61

1 1 1 1

1 1

1 1

1 1

P 69

1

P 77

1 1 1

1

1 1 1 1 1

1 1 1 1

P 85

1 1 1 1

1 1 1

1 1 1

1 1

1 1

1

1 1 1

1 1

1 1

1

1 1 1

1 1

1 1 1

P 93

1 1 1 1 1

1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1 1

1 1 1 1 1

1

1 1 1 1 1 1

1 1

1 1

1

1 1 1

1

1 1

1 1 1 1

1

1

1 1 1

1 1

1 1

+Ca P6

P 14

1 1 1 1 1 1

1 1 1 1 1 1

1

P 22

1 1 1 1 1

1 1 1 1

P7

without

Trial management

40

FYM+

+Ca

sowing 96 plots with a grass mixture (Lolium perenne and Festuca rubra) (Fig. 1).

60

0



 Originally, six systematically arranged replications  From 1923 to 2013, plots ploughed annually  White clover never sown (from 1923 onwards)  In spring 2014, three replicates taken out of arable management:

80

1 1 1 1

1 1 1 1 1 1

1 1 1 1 1

1 1 1 1 1

1 1 1 1 1

1 1

1 1

1 1

1 1

P 15

1 1 1

1

P3

1 1 1

1

1

1

1 1 1 1

1 1 1

1 1 1

P 23

1 1 1 1 1 1

1 1 1 1 1 1

P 38

1

1 1

1

1

P 31

1 1 1

1 1

1 1 1 1

1 1 1 1 1 1

P 46

1 1 1 1 1 1

1 1 1

1 1 1 1 1

1 1 1 1

P 39

P 54

1 1 1 1 1

1 1 1

1 1 1 1

1 1 1 1 1

1 1

1

1 1

1

1 1

1

P 47

1

P 62

1 1

1 1

1 1 1

1

1 1

1 1

1

P 55

1 1 1 1 1 1

1 1 1 1

1 1 1 1

1

1 1

1 1

1

1

1 1

1 1

1 1

1 1

1

1

1 1

P 63

1 1 1

1

P7

1 1

1

1

P 78

1 1 1 1 1 1

1 1 1 1

1

1

1

1 1 1

1 1

1 1

P 71

1 1 1 1 1

1 1 1 1 1

1 1 1 1

1 1 1 1

1 1 1 1 1

1 1

1 1

1 1

P 94

1 1

1 1 1

P 79

1 1

1

P 86

1

P 87

1

1 1

1 1 1 1

P 95

1

1

1 1

1

-Ca P8

P 16

P 24

P 32

P4

P 48

P 56

P 64

P 72

P8

P 88

P 96

1 1 1

1

1 1 1

1 1 1

1

1 1

1

Farm yard manure

+

—

+

—

+

—

+

—

+

—

+

—

Fig. 4: Trial map with presence (green) and absence (blank) of white clover in microplots.

Conclusions  Our study reveals the importance of after-effects of liming and 

farm yard manure application on performance of white clover. This has particular relevance for rotational leys in which white clover is often an important component, e.g. in organic farming.

Acknowledgements

The authors thank Jörg Schmidt for excellent management and maintenance of the long-term field trial.