Horticulturae

Agrivoltaic (AV) systems are emerging as a promising strategy to reconcile agricultural management and productivity with renewable energy generation, particularly in climate-vulnerable Mediterranean regions. This study evaluated the effects of static photovoltaic shading on the vineyard microenvironment, as well as the vegetative, productive, and microbiological responses of Vitis vinifera cv. ‘Falanghina’ grown under semi-arid conditions in Southern Italy, comparing high and low shading configurations with full sun (FS) exposure. Although the study was conducted during a single growing season, the vines in the AV system had been growing and adapting to their respective shading regimes for approximately eight years. The AV system modified the vineyard microclimate by reducing solar radiation, air temperature, and wind speed, thereby lowering atmospheric and soil water demand. These morphological adjustments were associated with improved photochemical performance and enhanced vine water status, as well as more effective gas exchange. The physiological and structural responses translated into variations in grapevine productivity: moderate shading (AVL) significantly increased yield per vine by 97.7% compared to FS conditions and by 54.6% compared to high shading (AVS). This increased productivity was achieved while maintaining berry quality comparable to the control, with only an 18% to 15% increase in titratable acidity with respect to FS vines. Beyond vine responses, under the assessed conditions, AV environment also influenced the endophytic culturable microbial community of phyllosphere, inducing early shifts in the relative abundance of dominant morphotypes without detectable changes in richness or Shannon diversity at either stage, although replication was limited. Under the conditions evaluated, AVL showed a possible favorable combination of physiological and productive responses. These findings support the potential of established agrivoltaic systems to mitigate environmental stress and maintain grapevine performance under Mediterranean conditions subjected to drought and high temperatures, while further multi-year studies are needed to assess the consistency of these responses across different growing seasons.

Marigold (Tagetes spp.) is an ornamental and functional crop valued for flower form and carotenoids. This preliminary single-season study characterized nine commercial cultivars of the Taishan (T. erecta), Durango, and Super Boy (T. patula) series grown in one greenhouse (one plot per cultivar; ten plants). Growth, biomass, flower morphology, color, and an absorbance-based lutein-equivalent index were combined with correlation analysis, principal component analysis (PCA), and clustering. Cultivars differed in all plant traits (descriptive Welch ANOVA, p ≤ 0.003) and height trajectories (cultivar × date, p < 0.001), but because plot and cultivar were confounded, these tests are descriptive only. Durango Yellow had the largest height increment between 8 and 22 June (10.25 cm versus ≤ 4.03 cm in the others). The lutein-equivalent index (one pooled sample per cultivar; not HPLC-validated) was highest in Super Boy Orange (46.88 mg g⁻¹ DW) and near the quantification limit in three cultivars. PCA of 12 traits explained 51.57% and 22.57% of the variance in PC1 and PC2, separating size and biomass from pigment, color, and architecture. PC1 was unchanged without the pigment index, whereas cluster composition depended on it. The data provide a descriptive baseline for replicated, multi-environment experiments with HPLC-validated pigment analysis.

In this study, we identified 34 HD-ZIP genes at the genome-wide level in P. trifoliata (Poncirus trifoliata (L.) Raf.), and conducted comprehensive bioinformatic analyses. The expression profiles of PtrHB genes in response to six phytohormones (ABA, SA, JA, BR, ETH, GA) and two abiotic stresses (dehydration, cold) were further determined. Phylogenetic analysis assigned all PtrHB proteins to four distinct subfamilies (I–IV) with highly conserved domain compositions, in line with the established classification system in Arabidopsis thaliana. Segmental duplication was revealed as the primary driver of PtrHB family expansion, whereas three tandem duplication events were also detected. Promoter cis-element profiling revealed subfamily-specific distribution of hormone- and stress-responsive elements. Several candidate genes with prominent stimulus-specific responses were highlighted, including PtrHB32 (strongly induced by dehydration, cold and ABA), PtrHB15 (JA-responsive) and PtrHB16 (SA-responsive). Collectively, this study provides the first systematic genome-wide analysis of the HD-ZIP transcription factor family in P. trifoliata, and offers valuable insights into the evolutionary expansion and functional divergence of this family. Our results also lay a theoretical basis for functional validation of candidate stress-regulatory genes and for molecular breeding of stress-tolerant citrus rootstocks.