Biology subjects

Tortorici, N.

Publications and source records attributed to Tortorici, N..

2 recordsLinked to original sources

bioRxiv2026

Integrated physiological markers of drought tolerance and yield stability in cotton under deficit irrigation

The selection of drought-resistant cotton genotypes with high productivity and improved water-use efficiency is an increasingly pressing challenge in arid and semi-arid cotton-growing regions, where climate variability is intensifying water scarcity. This study evaluated two widely cultivated cotton varieties in Texas, NG 4190 B3XF and ST 4990 B3XF, under full and moderate deficit irrigation to identify physiological markers associated with contrasting yield responses under water limitation. A comprehensive set of physiological traits was assessed, including plant water status, leaf gas exchange, carbon isotope composition ({delta}13C), total nitrogen and C/N ratio, chlorophyll fluorescence, light and CO{square} response curves, and canopy temperature. While no yield differences were observed under full irrigation, moderate water deficit resulted in stable seed and fiber yield in NG 4190, but significant yield reduction in ST 4990. Yield differences were not explained by instantaneous gas exchange or direct biochemical limitations of photosynthesis, but rather by integrated physiological behavior over time. Key discriminating traits included midday relative water content (RWC), photosynthetic light-response parameters ( and Pm), stomatal optimization parameter (g{square}), and {delta}13C. NG 4190 exhibited higher RWC, more negative {delta}13C, and higher g{square} values, indicating a less conservative stomatal regulation strategy that supported sustained carbon assimilation under water stress. These findings provide insight into the physiological mechanisms underlying cotton performance under drought and support the use of integrated physiological markers for the selection of resilient genotypes in water-limited environments.

plant biology↗

bioRxiv2026

Net radiation estimation using the Brunt equation for clear sky emissivity and air and canopy temperatures for longwave radiation in well watered crops

Net radiation (Rn) can be estimated using models that apply the Brunt equation for the incoming longwave radiation and air temperature (Tair) for the outgoing longwave radiation under reference conditions. This study aimed to estimate Rn using two previously regionally calibrated Brunt model, thereby eliminating the need site-specific calibration, and to assess whether Tair can be used as a substitute for canopy temperature (Tc) under well-watered crop conditions. Measurements were conducted in sesame and cotton fields during the first year and in a cotton field during the second year. Canopy temperature was measured during the second year, and the calculations were performed at hourly and daily time scales. Regardless of the method used to estimate sky emissivity or whether Tc or Tair was used, errors were greater at hourly time scale. The overall RMSE, MAE, Bias and KGE values at the daily time scales were 11.88, 9.13, 2.53, and 0.91, in the first year, and 13.45, 10.56, 0.10 and 0.74, in the second year, respectively. When using both regionally calibrated Brunt model, Rn simulation performance was superior to that of the Allen/FAO method. The comparison between Rn estimated using Tair and Tc, indicated statistical differences. Nevertheless, linear regression and error metrics showed that these differences were modest, especially at daily time scale. Thus, for practical purposes both regionally calibrated Brunt equations can be used to calculate clear-sky emissivity and improve Rn estimations, and Tair can be used as a substitute for Tc at the daily time scale under well-watered conditions.

ecology↗