WP 3: Field experiments and case studies in established cropping systems

The main objectives of this work package are to study the effects of conventional and organic cropping systems varying for input levels on the performance and impacts of breeding innovations and to generate the data necessary for the calculation of scenarios in WP5. Effects of different levels of diversity (Task 3.1) and minimum tillage in medium term experiments (Task 3.2) will be tested in replicated field trials. Finally, field experiments will be conducted inselected farms with long term established cropping systems (Task 3.3) to determine the interactive effects of genetic composition and agricultural system management that require that the changes in the systems are in place for some time already.

Task 3.1 Cropping systems with different degrees of diversity
Aims of the task are, to check by cross-validation for adaptation to competition with a living mulch. Comparisons will be made among genetically uniform and diverse wheat populations with or without histories of adaptation to living mulch. The plant material consists of  populations evolved for 5 years  with and without competition with a living mulch or weeds, (8 populations in total)  10 lines from CCP of differing morphological types and  10 selected commercial varieties. The trials are being performed in two locations: TUM (organic and conventional )  and  KU (organic). Treatments are the  presence and absence of competition by an intercrop (living mulch). Assessments include biomass/ground cover in the early stages, foliar and foot diseases, grain yield, yield structure and grain protein content.

Task 3.2 Field experiments in replicated field trials in established cropping systems
Aim of this task is the comparison of the performance of genetically uniform and  diverse wheat  populations with or without histories of adaptation to living mulch in different tillage systems with and without living mulch.
The experiments are based on previously established medium-term field experiments: At TUM and KU in the frame of the EU project "OSCAR", minimum tillage growing systems based on an innovative light weight direct drilling device have been established in replicated field trials since 2012. In 2015 and in 2016, replicated plots will be available with three years of minimum tillage versus conventional tillage with plough. At KU, half the plots were managed with two fertility levels. At TUM, an organically and a conventionally managed site are  available with differential  N-inputs at the conventional site. Thus differential cropping systems with respect to input and output  levels can be used to compare the adaptation of populations and pure lines to minimum tillage systems with undersowings. Plant material is a subset of the materials tested in WP3.1. The assessments include  biomass/ground cover in the early stages, foliar and foot diseases, grain yield, yield structure and grain protein content, soil parameters: N dynamics, humus contents, dynamics of  arbuscular mycorrhiza spore populations as well as  aggregate stability.

Task 3.3 Analysis of population performance, ecological impact, and management
in selected farming systems

The aim of the task is the  comparison of the performance of selected genetically uniform and diverse wheat populations in different established farming systems. The results of the strip trial will be used to compute the data for the indicators as basis of the system evaluation in WP5.

A total of 8 farms will be selected to represent different input levels with respect to fertility and tillage, among others. Strips the width of the farming equipment of two to three genotypes or populations will  be compared to the farmers’ variety. In the first year the farmers will manage the strips like his or her own variety. The management will be adjusted to fit the selected populations in subsequent years. Depending on the performance with respect to weeds, insects, and diseases plant protection inputs will be reduced.

The assessments include biomass development, soil cover, plant and insect biodiversity using  indicator insects and spiders, and N-uptake; foliar and foot diseases; grain yield, yield structure and grain quality; soil N dynamics, humus contents. Moreover, farm management data such as  Implements and inputs used, costs, time and energy are being assessed.