1. EWRS Joint Workshop. 4-8 September 2011. Huesca, Spain
Paper mulch controls purple nutsedge (Cyperus rotundus L.) in processing tomato
A. Cirujeda1, J. Aibar2, C. Zaragoza1
1Unidad de Sanidad Vegetal, Centro de Investigación y Tecnología Agroalimentaria (CITA), Zaragoza;
2Universidad de Zaragoza. Escuela Politécnica Superior Huesca
Huesca, September 7th, 2011

2. Cyperus rotundus L. is considered one of the world’s worst weed.

3. Despite its low size, this species can cause a reduction of up to 28% in the development of tomato (Morales-Payan et al., 2003).

4. CYCLE OF CYPERUS ROTUNDUS L. in the North of Spain (continental area)
SHORT DAY 9h
LONG DAY
12h
LIGHT Tª
LIGHT Tª
LIGHT Tª
Tª>20ºC
Tª<5ºC
Tª>15ºC
non- viable seeds
21A
21J
21S
21D
21A
SPRING
SUMMER
AUTUMN
WINTER
CYCLE OF CYPERUS ROTUNDUS L. in the North of Spain (continental area)

5. Cyperus rotundus infestation in a commercial farm without mulch.

6. IX Congreso SEAE: Calidad y Seguridad Alimentaria
Plastic mulch with black polyethylene (PE) is generally used in extensive horticultural crops in north-eastern Spain, like in tomato.

9. Objectives
In this work we present the effect of some types of paper used in tomato crop infested with C. rotundus during five years.

10. Material and methods Trial Year Material Company Colour Weight (gm2)
Material and methods
Table 1. Description of the treatments.
Trial
Year
Material
Company
Colour
Weight (gm2)
All
Untreated control - PE
Solplast
Black
16.4
Mater-Bi1
Novamont
22.3
Aula Dei
2005, 06
Saikraft 2002, 3
Saica
Brown
200
Aula Dei, S. Bruno
2007, 08
Saikraft 1402, 3
140
S. Bruno
2008, 09
Mimgreen2
Mimcord 90
2009, 10
Karpan Liner2
Smurfit-Kappa
120
MG2 50
1Biodegradable plastic
2Paper
3Paper coated on one side with an estiren-acrylate copolymer at 150 g/t.

11. Saikraft
Mimcord MG
Karpan Liner

13. Results

14. Results
Figure 1. Cyperus rotundus density 42 days after transplantation.

15. Results

16. Results
Paper mulch does not prevent Cyperus emergence but as far as it stands the physical pressure and does not break, the plants are not able to reach the light, develop chlorotic leaves, do not flower and die.

17. Results

18. Results

19. Results
Drawbacks: If rainfall is frequent, the paper becomes soft and do not dry and the control effect on Cyperus is not reached (Méndez et al., 2006 Northern Spain). This can also happen if the irrigation emitters are placed upwards and the paper is continously wet.
Another unconvenient of paper mulch is that in clay soils the degradation of the underground part of the paper mulch may be quite fast and the paper breaks down in the contact line of the mulch with the soil surface allowing the wind to damage it.

20. Results

21. Results
Tomato yield at the paper mulch treatments was very similar to that obtained in the PE all 5 years of experiments.

22. Economic aspects Mulching type €/kg* g/m2 €/ha** % Coments
Black PE 15 µ
1.85
16.4
202
100
Add aprox.150 € removal cost.
Saikraft 125 recycled Paper Saikraft 140 recycled Paper
0.47
0.46
125
140
391
429
193
212
Shorter rolls for same weight
MaterBi (biodegradable plastic)15µ
4.75
22.3
706
350 -
Biofilm (biodegradable plastic) 17µ
5.8 21
818
404
Black Paper Mimcord 135µ
1.5
90.3
903
446
Good installation. Shorter rolls for same weight
*It does not include installation. Prices in Spain, 2010
**2/3 field area covered (1,50m between rows, 1,20m mulch width)

23. Conclusions
Paper mulch is an efficient weed control method including Cyperus spp. unless the mulch is not under continous moisture conditions.
Another advantage is the complete degradation of the paper after burial.
The main constraints compared to PE is the price (nowadays), the slower installation and the heavier weight of the rolls.

24. EWRS Joint Workshop. 4-8 September 2011. Huesca, Spain
Thanks for your attention!