Lead researcher: 
Alicia Cirujeda Ranzenberger
147.000 €
The present project aims to contribute to solve the problem of weed control in perennial crops, in newly-established plantations as well as in older plantations. Herbicide use in the first years is complicated because of the reduced number of allowed active ingredients, because of possible phytotoxicity and because of herbicide-resistant weed populations. Mowing is a good alternative in well-established plantations but young trees can be hurt during the operation. Also in pluriannual horticultural crops such as artichokes weed control is complicated and the method proposed in this project has the additional potential to reduce irrigation water amounts. Specifically, a biodegradable mulching material is proposed to be developed in this project to be applied in liquid form on the field solidifying afterwards and to study the effect of different mixtures applied on pluriannual crops. The project aims to provide al alternative to other weeding techniques in these crops, in which the biodegradable mulching materials available in the market degrade too fast offering a too short weed-free period to the crops. The basic materials for the hidromulch elaboration will be a) postharvest crop residues of mushroom production (SPCH) containing wheat straw rests, gypsum and chicken manure and b) recycled paper paste.
The first objective will be to find the appropriate mixture of both ingredients that assures an easy application of the hidromulch with the minimum technical problems as possible. Afterwards, different additives (gypsum, guar gum, polivinil acetate) will be tested with the purpose that the mixture remains outdoors in good conditions during the longest period as possible. In this first phase we will have the technical advice of a researcher with experience in hidromulch, an expert in paper technology and an expert in bioconstruction materials. There has been fruitful collaboration with all three researchers previously.
The second objective considers studying the behaviour of the selected hidromulch mixtures applied outdoors on pluriannual crops. Therefore, once four different mixtures have been prepared with their respective additives they will be applied on pluriannual crops in a common trial: artichoke in Murcia and Navarra; stone fruit trees and vineyard in Zaragoza and Lleida and olives and almond trees in Ciudad Real. Different fruit tree experts will act as consultants in this part. In these trials all subprojects will carry out similar tasks regarding basic material characterization in time, weed control and studying the possible effect of the hidromulches on crop development and yield. Additionally, different tasks will be carried out corresponding to the respective specialities of the researchers participating in the subproject, those from Barcelona included . These specific objectives aim to study the effect of the hidromulches on most possible aspects: study of the resistance, durability and thermal behaviour of the hidromulches; chemical analysis; detailed effect of the hidromulches on the physical soil traits; effect on weeds; effect on irrigation water consumption; effect on the microorganisms and soil fauna and, finally, economic study of the hidromulch application on pluriannual crops.
Project members: 
Gabriel Pardo, A.I. Mari León (CITA); I. Lahoz García, I. Garnica (ITGA); J. Aibar Lete (Universidad de Zaragoza): J. Escartín, S. J. Fuertes Lázaro (DGA); A. Korpela (Univ. Helsinki)