Impact of different shading conditions on processing tomato yield and quality under organic agrivoltaic systems.

Agrivoltaics have emerged as a promising solution to mitigate climate change effects as well as competition for land use between food and energy production. While previous studies have demonstrated the potential of agrivoltaic systems to enhance land productivity, limited research has focused on their impact on specific crops, particularly in organic processing tomatoes. In the present study, a two-year experiment was conducted in northwest Italy to assess the suitability of the agrivoltaic system on processing tomato yield and quality in the organic farming system. In the first growing season, the transplanting of tomato was carried out under the following light conditions: internal control (A1)—inside the tracker rows obtained by removing PV panels; extended agrivoltaic panels—shaded condition with an increased ground coverage ratio (GCR) of 41% (A2); and external control (FL)—full-light conditions outside the tracker rows. The second year of experimentation involved the transplanting of tomato under the following light conditions: internal control (B1); dynamic shading conditions that consist of solar panels in a vertical position until full fruit set (B2); standard agrivoltaic trackers (GCR = 13%, shaded conditions) (B3); and external control (FL). In 2023, the results showed that A2 achieved a total yield of only 24.5% lower than FL, with a marketable yield reduction of just 6.5%, indicating its potential to maintain productivity under shaded conditions. In 2024, B2 management increased marketable yield by 80.6% compared to FL, although it also led to a 46.2% increase in fruit affected by blossom end rot. Moreover, B2 improved nitrogen agronomic efficiency and fruit water productivity by 6.4% while also reducing the incidence of rotten fruit. Our findings highlight that moderate coverage (A2 and B2) can sustain high marketable yields and improve nitrogen use efficiency in different growing seasons.