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In this paper molecular analysis, physical, technological, and chemical traits were used to estimate the level of variation on five accessions of a locally adapted Sicilian faba bean (Vicia faba L.) landrace named 'Larga di Leonforte'. DNA analysis was performed using the Amplified Fragment Length Polymorphism (AFLP) molecular marker class and two other faba beans (cv. 'Aguadulce Samba'-Spain-and landrace 'Locale di Modica'-Sicily) were used as controls. Although the accessions of 'Larga di Leonforte' varied significantly for most of the agronomical and physical traits, this landrace generally had a heavy seed weight, short but large pods, and no more than two seeds per pod. This last characteristic allowed for erect pod angle attitude at maturity. Idratation data showed difference among accessions in seed weight at full hydration and in absorption rate at the very beginning of the hydration process, while any difference among accessions emerged in terms of cooking properties. The six AFLP Eco?3/Mse?3 different primer combinations applied in this research revealed different levels of polymorphism among the faba bean accessions and a total number of 346 amplicons were generated. Around 60% of amplicons displayed a polymorphic pattern among different accessions. Cluster analysis on morphological, technological, chemical and molecular data placed the all five 'Larga di Leonforte' accessions into a separated group, and the Sicilian material shares a fairly large amount of similarity with respect to the cultivar 'Aguadulce Samba' selected in Spain.

Seed respiration has been utilized as an index of seed vigour and has correlated well with seedling development. We examined the respiration process as affected by temperature and osmopriming during imbibition in two cultivars of sorghum [Sorghum bicolor (L.) Moench] differing in capacity to germinate at low temperatures. Respiration of imbibing seeds was measured with a specially built apparatus linked to an infrared gas analyser. Seed respiration at the beginning of the imbibition process strictly depended on temperature (T). T also greatly affected the total CO2 respired to reach the first germination event, which significantly increased as T declined from the optimum. Osmopriming affected seed respiration differently in the two cultivars. In the cold-tolerant cultivar (Brandes), osmopriming reduced the total thermal requirements and, at T close to the minimum for germination, the energy required to achieve the first radicle protrusion. In the cold-sensitive cultivar (H128), osmopriming lowered base T for respiration and reduced the requirements for total CO2 respired, allowing germination even at 10°C. The cold-tolerant cultivar always maintained higher respiration rates than the cold-sensitive one, showing a greater capability of mobilizing energy from reserves. Germination time (i.e. GR50) related well to cumulative seed respiration down to a threshold value of cumulative CO2, after which GR50 was more affected by T than was cumulative respiration. Seed water uptake significantly slowed with decreasing T, and was accelerated by osmopriming. However, water imbibition rate influenced the start of seed respiration, but not the subsequent rate of metabolic activity preceding germination. Seed respiration was a good indicator of the activation of germinative metabolic processes, although under extreme T conditions the seed populations still respired, even if at low levels, but did not germinate rapidly or completely.

Genetic analyses have suggested that the clonal reproduction of Arundo donax has resulted in low genetic diversity. However, an earlier common garden phenotyping experiment identified specimens of A. donax with contrasting biomass yields (ecotypes 6 and 20). We utilized the same well-established stands to investigate the photosynthetic and stress physiology of the A. donax ecotypes under irrigated and drought conditions. Ecotype 6 produced the largest yields in both treatments. The A. donax ecotypes exhibited identical high leaf-level rates of photosynthesis (P N ) and stomatal conductance (G s ) in the well-watered treatment. Soil drying induced reductions in P N and G s , decreased use of light energy for photochemistry, impaired function of photosystem II and increased heat dissipation similarly in the two ecotypes. Levels of biologically active free-abscisic acid (ABA) and fixed glycosylated-ABA increased earlier in response to the onset of water deficit in ecotype 6; however, as drought progressed, the ecotypes showed similar increases in both forms of ABA. This may suggest that because of the low genetic variability in A. donax the genes responding to drought might have been activated similarly in the two ecotypes, resulting in identical physiological responses to water deficit. Despite the lack of physiological ecotypic differences that could be associated with yield, A. donax retained a high degree of P N and biomass gain under water deficit stress conditions. This may enable utilization of A. donax as a fast growing biomass crop in rain-fed marginal lands in hot drought prone climates.

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"Long-storage" tomato ( Solanum lycopersicum L.) is a niche product typical of the Mediterranean area, traditionally cultivated under no water supply, the fruits of which combine a good taste with excellent nutritional properties. High-performance liquid chromatography coupled with diode array detection and electron spray-mass spectrometry (HPLC/DAD/ESI-MS) was used to identify the phenolic profile in 10 landraces of long-storage tomato, grown under a typical semiarid climate, as compared to a processing tomato hybrid cultivated in the same environment, under both well-irrigated and unirrigated conditions. Sixteen different secondary metabolites, belonging to the classes of cinnamoylquinic acids and flavonoids, were identified. Quantitative analyses were also performed to monitor the changes in the phenolic content along the batch. The results highlighted that landraces originating from the same area exhibit different fruit morphologies but own a similar biochemical profile. Moreover, the two controls (well irrigated and unirrigated) are placed into the same cluster, suggesting that these secondary metabolites in tomato fruits may be more genetics-dependent than environment-dependent. Given the analysis of phenols nowadays represents a useful tool to assess the genetic variability in tomato, these compounds could be adopted as chemotaxonomic markers in the traceability of this niche product.

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