Field-crop Production and Plant Breeding

The Syndrome Basses Richesses (SBR) is a bacterial disease transmitted to beets by the planthopper Pentastiridius leporinus. The planthopper infects the crop during the summer before laying eggs in the soil. The larvae will then develop by feeding on the beet roots, then on the following crop until their emergence flight in spring.
Within the framework of a research network on sugar beets, the BFH-HAFL conducted field trials, financed by the Swiss Beet Center (SFZ/CBS) and the BFH-HAFL, to study the influence of the crop following sugar beets on the development of the planthopper P. leporinus. The emergence of planthoppers was compared between a maize crop and a winter cereal.

The maize cultivation allowed a decrease of more than 97% of the planthopper flights. The absence of crops, and therefore of food, stopped the development of the planthoppers during the winter.

It is therefore recommended to avoid winter cereals after sugar beet to control the transmission of SBR. It is necessary to implement this measure at a regional scale to be effective from now on.

Silver scurf and Colletotrichum are two fungus diseases that diminish the skin quality of potatoes. Furthermore, tubers infected with silver scurf lose water during storage and shrink. Both diseases lead to large financial losses in washed potatoes intended for fresh market sales. The research partners BFH-HAFL, Agroscope and FiBL are therefore collaborating with Swisspatat, Biosuisse, Andermatt Biocontrol, Terralog and Omya on a project. The objective of this project is to find concrete solutions for the integrated management of both diseases along the entire value chain from field to shop.

An adequate water supply is decisive for optimum yields and top quality. Nowadays irrigation is mostly by ‘feel’, i.e. without any technological aids. To optimise irrigation practices, we and the Dutch company RMA began setting up a network of soil sensors throughout Switzerland in 2016. This network currently comprises ca. 130 sensors in potato and vegetable fields. By continuous, field-specific measurement of soil moisture content, soil moisture tension and precipitation, we are able to adapt and thus optimise the irrigation strategy in accordance with the specific water needs of the crops. The sensor measurements are available in graphic form at: www.bewaesserungsnetz.ch.
There are some 50 of these soil sensors in the Canton of Vaud. The ‘Efficience Irrigation Vaud’ project provides funding for farm-wide irrigation analyses and for purchasing drip irrigation systems and soil sensors. The goal is to achieve more efficient water use in agriculture. In the scope of scientific support (2018–2025), we will investigate irrigation strategies and the influence of soil properties and production techniques on 15 pilot farms. We will also analyse the impacts of the project measures on irrigation strategies.

In the 1990s, cultivation to control weeds was still fairly widespread in Swiss sugar beet fields. However, broadcast herbicide applications are used almost exclusively nowadays. In collaboration with Interprofession Zucker, BFH-HAFL researchers are investigating the potentials and limits of various mechanical-chemical methods for controlling weeds in sugar beets. They are studying the combined use of cultivation equipment, band or underleaf applications of herbicides in mulch seeding and applications when ploughing after different catch crops. The goal of the project is to develop practical recommendations that would enable a 50 per cent reduction in the amount of herbicide typically used on farms today.

Around 2,200 tons of plant protection products – 40% of which are herbicides – are sold each year in Switzerland. The Confederation is striving for a significant reduction. This can be achieved by using robots for targeting applications to the weeds. We are testing and improving the ecoRobotix robot, alone and in combination with modern cultivating tools, in sugar beet, rape and onion fields. The goal is to develop a basic concept for reducing herbicide use. In the first two project years, we will conduct field experiments with the aim of optimising the robot’s ability to distinguish crop plants from weeds and maximising the accuracy of the robot in the three crops. Depending on the outcome, we will conduct experiments at different sites in combination with other techniques in the third and fourth project years. We will then use these results to calculate the reduction potential and economic efficiency in field crop and vegetable production.

The stem nematode, Ditylenchus dipsaci, is a threat to some 4,000 hectares of sugar beet in Switzerland alone. Infection by this nematode leads to necrosis and rot, which can mean up to 50% yield loss. There are currently no effective chemical control measures against this pest. Tolerant cultivars in combination with late sowing is a less than satisfactory alternative, and it does not offer any sustainable prospects for the affected production areas. Besides preventive measures such as long rotations, the use of resistant cultivars is the only option for sustainable control of D. dipsaci in infested fields. In the scope of a PhD project and in cooperation with KWS Saat SE, Schweizerische Fachstelle für Zuckerrübenbau (Swiss expert centre for sugar beet production), Julius Kühn-Institut and the University of Göttingen, we are studying resistance against D. dipsaci in sugar beets.