Diversifying crop rotations with temporary grasslands - Université de ...

B.II.2 Design of the field experiment ...................................................................... 41
B.II.3 Data collection ............................................................................................... 42
B.II.4 Statistical analysis ......................................................................................... 42
B.III GREENHOUSE EXPERIMENTS ANALYZING THE REGROWTH CAPACITY OF WEED
PLANTS AFTER CUTTING
B.III.1
........................................................................................ 42
Rationale ........................................................................................................ 42
B.III.2 Design of the greenhouse experiments .......................................................... 43
B.III.2.1 Differences between species ....................................................................... 43
B.III.2.2 Plant biomass .............................................................................................. 43
B.III.2.3 Plant age ...................................................................................................... 43
B.III.2.4 Cutting height .............................................................................................. 44
B.III.2.5 Interactions between cutting and competition ............................................. 44
B.III.3 Cutting treatment and data collection ............................................................ 44
B.IV FIELD EXPERIMENTS ANALYZING WEED SEED PREDATION
B.IV.1
.................................. 44
Rationale ........................................................................................................ 44
B.IV.2 Measuring weed seed predation .................................................................... 45
B.IV.3 Design of the seed predation experiments ..................................................... 46
B.IV.3.1 Weed species ............................................................................................... 46
B.IV.3.2 Vegetation cover ......................................................................................... 46
C RESULTS (ARTICLES & MANUSCRIPTS) ............................................................... 47
C.I IMPACTS OF TEMPORARY GRASSLANDS ON WEED COMMUNITIES (CHIZÉ) ......... 47
C.I.1 Article 1: Meiss, H., Médiène, S., Waldhardt, R., Caneill, J. & Munier-
Jolain, N. (2010a) Contrasting weed species composition in perennial alfalfas and six
annual crops: implications for integrated weed management. Agron. Sustain. Dev. 30,
657-666. 47
C.I.2 Article 2: Meiss, H., Médiène, S., Waldhardt, R., Caneill, J., Bretagnolle, V.,
Reboud, X. & Munier-Jolain, N. (2010b) Perennial alfalfa affects weed community
trajectories in grain crop rotations. Weed Research 50, 331-340. ................................ 58
C.II EXPERIMENTAL ANALYSES OF THE IMPACTS OF TEMPORARY GRASSLANDS ON
WEED POPULATIONS ............................................................................................... 69
Manuscript 3: H Meiss, R Waldhardt, J Caneill, N Munier-Jolain (in preparation)
Mechanisms affecting population dynamics of weeds in perennial forage crops. ....... 69
C.II.1 Introduction ................................................................................................... 70
C.II.2 Methods ......................................................................................................... 73
C.II.2.1 Experimental design .................................................................................... 73
C.II.2.1.1 Weed seed addition ................................................................................................... 75
C.II.2.2 Measurements ............................................................................................. 76
C.II.2.2.1 Plant densities ........................................................................................................... 76
C.II.2.2.2 Biomass ..................................................................................................................... 76
C.II.2.2.3 Chemical soil parameters .......................................................................................... 77
C.II.2.3 Statistical analysis ....................................................................................... 79
C.II.2.3.1 Emerged weed densities ............................................................................................ 79
C.II.3 Results ........................................................................................................... 79
C.II.3.1 Dynamics of emerged weeds ...................................................................... 79
C.II.3.1.1 Dynamics of weed plant density and diversity .......................................................... 79
C.II.3.1.2 Dynamics of weed community composition ............................................................. 82
C.II.3.1.3 Dynamics of individual weed species ....................................................................... 84
C.II.3.1.4 Effect of weed seed addition ..................................................................................... 89
C.II.3.1.5 Dynamics of weed and crop biomass ........................................................................ 90
C.II.4 Discussion ..................................................................................................... 95
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