Genetic diversity in two Italian almond collections

Background Sweet-seeded domesticated almonds were brought to the Mediterranean Basin from central Asia about 4000 years ago. In Italy, most of the almonds produced are cultivated in the southern part of the country. Local populations of the tree in Sardinia are largely seed-derived and mostly self-incompatible, so have developed extensive genetic diversity. The need to protect biodiversity has prompted a revived interest in local genetic materials in almond. Two Italian collections have been established, one in Sardinia and the other in Apulia. These collections were the focus of the present evaluation of genetic diversity. Results Eleven SSRs (microsatellites) were used for fingerprinting. The Sardinian germplasm was highly polymorphic, revealing a mean of 14.5 alleles per locus and a mean heterozygosity of 0.71. Using a model-based clustering approach, two genetic clusters were distinguished: one included all the commercial varieties and most of the Sardinian accessions, and the other most of the Apulian accessions. A similar structure was produced using a distance-based cluster analysis. The Sardinian accessions could still be distinguished from the commercial germplasm with few exceptions. Conclusion The extensive genetic variability present in the Sardinian and Apulian almond germplasm indicates that these materials represent an important source of genes for the improvement of the crop.

Protein and mineral nutrient contents in kernels from 72 sweet almond cultivars and accessions grown in France, Greece and Italy.

Almond protein and potassium (K), phosphorus (P), calcium (Ca) and magnesium (Mg) contents were determined in 72 cultivars and accessions grown in France, Greece and Italy, as part of the networking of European SAFENUT AGRI GEN RES project, which aimed to explore and valorize the almond genetic resources in Europe. Great variation was found in the nutrient content and the amount of nutrient supplied when consuming the recommended daily amount of one serving of almond, among the different genotypes assayed. The variation among the different genotypes was greatest for Ca, followed by the protein content; the latter also exhibited the lowest variation considering the harvest year. Results from a principal component analysis showed that P and Mg were the most discriminant elements for categorizing samples. Cluster analysis showed groups of samples with interesting characteristics for breeding. There was no clear distinction among the different origins of samples. Correlation analyses between weather conditions and the nutrients assayed showed that the mean temperature recorded in the period between March and September was positively correlated with Ca and P only in France, a place where the greatest climatic difference between years was observed.

Effects of tillage and nitrogen fertilisation on triticale grain yield, chemical composition and nutritive value.

BACKGROUND: Given the interest in the development of cultivation systems with low agronomic input and environmental impact, the aim of this study was to determine the influence of tillage system (conventional tillage (CT), two-layer tillage (TT), surface tillage (ST) and minimum tillage (MT)) and nitrogen (N) fertilisation rate (0, 50 and 100 kg ha(-1)) on triticale grain and protein yields, chemical composition and nutritive value. RESULTS: There were no significant differences among tillage treatments in grain and protein yields. ST resulted in significantly higher crude protein (CP) and true soluble protein (TSP) contents as well as in vitro crude protein digestibility (CPD). Neutral detergent fibre concentration was significantly higher with ST than with MT, and this led to a small reduction (2 g kg(-1) dry matter (DM)) in in vitro true DM digestibility (IVTDMD). N fertilisation significantly increased grain and protein yields as well as CP, non-protein nitrogen and TSP contents and CPD. IVTDMD was significantly lower with 0 kg N ha(-1) than with 50 and 100 kg N ha(-1). CONCLUSION: Reducing tillage intensity improved the CP content and CPD of triticale grain. The application of 50 kg N ha(-1) resulted in good grain quality parameters and grain and protein yields.