Authors:A. Rascio, E. Carlino, G. Santis and N. Fonzo
This study is a multivariate discriminant analysis that was performed to identify a set of physiological characteristics that can be used to distinguish between groups of durum wheat genotypes differing for adaptation to semi-arid environments. To this aim, at first twenty-six genotypes were classified as “adapted”, “nonadapted” or “indeterminate” on the basis of yield and yield stability, as determined in a drought-prone environment of southern Italy, over a minimum of 4 and a maximum of 9 years. Subsequently fifteen morpho-physiological traits and the yields were assessed in a field study. Univariate statistical analysis of morpho-physiological traits to compare genotypes and groups of genotypes showed significant differences between the genotypes, although no single character could be used to discriminate between the genotype groups. On the contrary discriminant functions, based on 13 morpho-physiological traits, were effective for the full discrimination of all of the groups, with a 100% success rate. Four traits was the minimum needed to fully discriminate the “adapted” genotypes. Together with the water status parameter, the rheological properties and the affinity for bound water are new promising leaf traits, to distinguish between the plants coming from these different groups.
Authors:E. Santi, E. Mari, S. Piazzini, M. Renzi, G. Bacaro and S. Maccherini
Farmland ponds represent habitats with a high conservation value that make a significant contribution to regional biodiversity. Understanding the influence of plant species composition and environmental variables in driving variations in animal species composition in ponds is an important issue in the fields of ecological research and conservation biology. Using variance partitioning techniques to quantify independent effects, we examined how plant species composition, local-landscape configuration and physicochemical variables interact in influencing aquatic insect and amphibian community composition. The ponds investigated in this study were located in the Site of Community Importance — Special Protected Area (Natura 2000 Network) “Monte Labbro — Alta Valle dell’Albegna” (Tuscany, central Italy). Our results showed that: (i) plant community composition (such as Carex hirta, Glicerya fluitans, Potamogeton natans, Typha latifolia) is a good predictor for amphibian but not for aquatic insect species composition; (ii) aquatic insect species composition was more strongly affected by the landscape context, whereas for amphibians the local characteristics of the ponds were determining; (iii) the physicochemical context is a poor predictor for these animal taxa; (iv) lastly, and notably, the explanatory variables explained a high proportion of the total variation in amphibian and aquatic insect species composition. Our results have important implications with respect to the creation of new ponds, which should preferentially take place close to semi-natural grasslands and other wetlands, in order to maintain greater connectivity, and away from urban areas. Moreover, larger ponds are preferable for the preservation of pond biodiversity. The management and conservation of ponds is necessary to ensure the protection of habitats, the survival of individual species and overall pond biodiversity.