Modern Wheat Varieties as a Driver of the Degradation of Spanish Rainfed Mediterranean Agroecosystems throughout the 20th Century

Climate change in the Catalan Pyrenees intersects with socioeconomic factors to shape crop diversity and management

Most studies on climate change's impacts on agriculture focus on modeling techniques based on large-scale meteorological data, while few have investigated how farmer's perception of climate change's impacts can affect crop diversity and crop management practices, especially in industrialized contexts. To fill this gap, we conducted 24 semi-structured interviews in a study site located in the Catalan Pyrenees. Our results show for the first time in an industrialized context that farmers perceive multiple interrelated climate change impacts on local agroecosystems. For instance, snowfall and freeze events have decreased, which respondents associated with the increase of pests and diseases affecting both wild flora and cultivated plants. Similarly, changes in precipitation patterns lead to a perceived decrease in useful rain for agriculture. Farmers are also reporting changes in their management practices, such as increased irrigation or use of pesticides, which respond to these climatic factors but also to changes in the crops that are cultivated. Crop diversity is in decline in the area both at the species and landrace levels, especially in rainfed fields. This is mainly driven by socioeconomic factors such as agricultural abandonment or access to commercial seeds, although climate change factors such as increased pests or decreased rainfall can have an impact. Despite the crop diversity losses found, many landraces have been maintained, mainly due to their cultural value, and also new crop species have been introduced, which are now viable due to the increase in temperature. Although we focused on a specific case study, we found several trends that are also present in other contexts. Therefore, the results of this research are relevant at a global scale since they show that climate change is affecting mountain agroecosystems in industrialized contexts and may affect more drastically both agrobiodiversity and crop management practices in agroecosystems worldwide.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13593-022-00806-3.

Yield and Quality Performance of Traditional and Improved Bread and Durum Wheat Varieties under Two Conservation Tillage Systems

The increasing spread of conservation agriculture demands that the next generation of wheat varieties includes cultivars capable of maintaining satisfactory yields with lower inputs and under uncertain climate scenarios. On the basis of the genetic gains achieved during decades of selection oriented to yield improvements under conventional crop management, it is important that novel breeding targets are defined and addressed. Grain yield, yield-related traits, and phenological and morphological characteristics, as well as functional quality parameters have been analyzed for six varieties each of bread and durum wheat, under minimum tillage and no-tillage. During the three-year experiment, the climatic conditions at the field trial site were characterized by low rainfall, although different degrees of aridity—from moderate to severe—were experienced. Differences were found between these two soil management practices in regard to the varieties’ yield stability. A positive influence of no-tillage on traits related to grain and biomass yield was also evidenced, and some traits among the examined seemed involved in varietal adaptation to a particular non-conventional tillage system. The study also confirmed some breeding targets for improved performance of wheat genotypes in conservation agroecosystems. These traits were represented in the small set of traditional varieties analysed.