LW-R-3+4: Adaption the variety spectrum,maize varieties by maturity groups
2019 Monitoring Report on the German Strategy for Adaptation to Climate Change
2019 Monitoring Report on the German Strategy for Adaptation to Climate Change
Increasing amounts of warmth signify that even particularly thermophilic red grape varieties become suitable for cultivation in German cultivation areas. Although the cultivation area used for growing the internationally popular red grape varieties Merlot and Cabernet Sauvignon is still limited, there are indications that it is in the process of expanding significantly.
So far, there is no evidence for a discernible trend towards an increase in applications for approval of early ripening maize varieties submitted to the Bundessortenamt. Currently, this development seems to be masked by other effects.
Similar to the opportunities for adaptation by means of cultivating thermophilic crop species, the choice of varieties is a means for farmers to respond to changes in circumstances by retaining the same crop species but considering a change in crop variety. In such decisions preference is given to varieties which promise high-quality crops, secure yields and good chances for sale and marketing when faced with the expected change in circumstances. Naturally, the choice of variety will always be the outcome of factors weighed up by farmers in their decision-making process. In all those deliberations, the weather pattern is only ever one of several factors. Occasionally, the choice of variety can be a spontaneous decision, informed primarily by a farmer’s experience gained in the most recent cultivation period or by market chances which might become apparent at the time of decision-making.
In deciding on annual crop varieties farmers can be relatively flexible. However, with regard to perennial crops they have to make a long-term commitment when deciding on a specific variety. In viticulture, for instance, the crop variety requires careful deliberation, because vines have a long lifespan of up to twenty or thirty years. This requires vintners to make longer-term production decisions when planting a new vineyard. Besides, wine happens to be an agricultural product which potentially offers extremely high added value and major commercial importance at the same time requiring comparatively little cultivation space. Consequently, a great deal of attention is paid to the choice of variety.
For assessing the cultivation potential of specific grape varieties in different wine-growing regions, the so-called Huglin Index is used. It totals the days with temperatures of more than 10 °C for the period of 1st April to 30th September and indicates whether the amounts of warmth required by a grape variety for successful cultivation over an extended period can be achieved in a particular region. In the course of the past approximately forty years the Huglin Index has risen significantly for the whole of Germany. This has resulted in some, so far predominantly highly thermophilic red grape varieties – hitherto limited to southern regions – becoming suitable for the cultivation of vines in German areas of cultivation. Such varieties include Merlot, Cabernet Sauvignon and Syrah. These grape varieties are highly acclaimed internationally which makes some vintners very keen to cultivate them subject to suitable climatic conditions. The areas where Merlot and Cabernet Sauvignon are cultivated, as recorded by wine statistics since 2002, are still comparatively small. However, the increase in vineyard space dedicated to growing these varieties indicate mounting interest. It is to be expected that climate change will in future be reflected in the choice of grape varieties in Germany.
Breeders organise the development of their varieties in line with the new requirements. The applications for approval of varieties received every year by the Bundessortenamt (German office for the approval of varieties) provide clues indicating which variety properties are being developed by breeders. Nevertheless, it typically takes between eight and ten years to breed a new variety, i.e. the figures do not always reflect any changes in demand for a variety in real time. The use of modern methodology in plant breeding research might result in a more rapid and more efficient provision of varieties adapted to changed climate conditions such as drought or increased CO2 concentrations. The use of early ripening varieties of grain maize increases the probability that higher dry matter contents can be achieved in harvesting thus reducing the drying costs involved. As a result, early ripening varieties might become more attractive. It must be said, however, that the late ripening varieties still offer higher yield potentials. Current breeding efforts therefore focus on developing early ripening maize varieties with greater yield potential.
Furthering innovations in plant breeding with a view to adaptation to climate change, the nutrient regime of cultivated plants and properties relating to resistance and quality (DAS, ch. 3.2.6)