Studi ecofisiologici sui sistemi agroforestali per potenziare la resilienza e la sostenibilità nella coltivazione delle colture erbacee

Climate change is one of the leading threats to agricultural production stability; thus, the development and implementation of sustainable cropping systems becomes absolutely necessary. Silvoarable systems, which represent an integration of trees with crops, offer considerable ecosystem services that can balance some of the detrimental effects of intensive agriculture. New HES poplar clones are studied in growth and phenology-in a traditional plantation design and in a low-density silvoarable alley system. Different cultivars of winter wheat and cereals, under artificial shading conditions simulating a silvo-arable environment, were studied from 2021 to 2023. It was found that the silvo-arable system showed a diameter increase of 16% for poplars but a height decrease of 8% compared to a conventional plantation. This advantage in growth was because of less competition. During the period 2019-2024, grain yields of winter wheat next to the trees were equal or even higher compared with the center of the poplar rows. Losses of yield in summer crops, such as maize, because of shading reached up to 27%. Microclimatic differences showed that the west side of the tree rows was better for winter crops, while for summer crops, the east side was less problematic. Interactions between trees and crops proved to be quite variable. Poplar rows enhanced microclimatic conditions due to soil moisture retention and reduced temperatures but competed for light. Artificial shading trials did manage to simulate agroforestry systems, resulting in increased yields on the west aspect of shading barriers. Modern varieties of wheat adapted very well to shading but resulted in lower relative yields as compared to local varieties. In barley and triticale, artificial shading caused positive morphological responses, but yields were reduced. Overall, poplars grown in widely spaced silvoarable systems could grow faster due to their improved accessibility to light and soil resources. The study concludes that dynamic artificial shading may allow species selection for shading tolerance. However, local varieties show mechanisms that could be adaptive under severe shading conditions, while modern wheat varieties grow well under full sun as well as under shading conditions. Growing forage varieties of winter cereals is also advisable, since biomass is less affected compared to grain yields. Further analysis of phenology and photosynthetic parameters will increase genotype identification tolerant to shading.