Treasuring crop wild relative diversity: analysis of success from the seed collecting phase of the ‘Adapting Agriculture to Climate Change’ project

The seed collecting phase of the ‘Adapting Agriculture to Climate Change’ project was, to the best of our knowledge, the most comprehensive crop wild relatives (CWR) collecting and conservation mission to-date and provides priceless genetic diversity for ongoing and future crop breeding efforts. The seed collecting started in 2013 and was concluded in 2019, it was carried out in 22 countries in Africa, Asia, the Americas and Europe, involving CWR taxa of 28 different crop genepools. 3002 target seed accessions of 242 taxa were collected and are currently stored long-term in the countries of collection and, in most of the cases, backed up at the Millennium Seed Bank (UK). Considering also non-target species, 3854 seed accessions were collected. For the genepools of bambara groundnut (Vigna subterranea (L.) Verdc.), barley (Hordeum L.), grass pea (Lathyrus sativus L.), sorghum (Sorghum bicolor (L.) Moench), and wheat (Triticum L.), the collecting phase was highly successful in terms of diversity of both, species and populations. Despite the overall success of the project, in our analysis we discovered several issues that were encountered in the seed collecting. In particular, comparing the initial collecting targets with the seed accessions effectively collected it emerges that: (1) some important crop genepools were characterized by a low collecting success (e.g. banana/plantain (Musa L.), potato (Solanum tuberosum L.), rice (Oryza L.), (2) genepool 1 (the most important for breeding efforts) of some crop genepools was under-collected (e.g. eggplant (Solanum L.) and sorghum), (3) some important centres of plant biodiversity (especially the Indian Subcontinent) were underrepresented in the seed collecting. This analysis can guide further collecting missions in order to fill gaps in the long-term conservation of CWR of great importance for crop improvement.

     

Metabolite profiling of grape: Flavonols and anthocyanins

Flavonols are products of the flavonoid biosynthetic pathway, which also give rise to anthocyanins and condensed tannins in grapes. We investigated their presence in the berry skins of 91 grape varieties (Vitis vinifera L.), in order to produce a classification based on the flavonol profile. The presence of laricitrin 3-O-galactoside and syringetin 3-O-galactoside in red grapes is reported here for the first time. In red grapes, the main flavonol was quercetin (mean = 43.99%), followed by myricetin (36.81%), kaempferol (6.43%), laricitrin (5.65%), isorhamnetin (3.89%), and syringetin (3.22%). In white grapes, the main flavonol was quercetin (mean = 81.35%), followed by kaempferol (16.91%) and isorhamnetin (1.74%). The delphinidin-like flavonols myricetin, laricitrin, and syringetin were missing in all white varieties, indicating that the enzyme flavonoid 3',5'-hydroxylase is not expressed in white grape varieties. The pattern of expression of flavonols and anthocyanins in red grapes was compared, in order to gain information on the substrate specificity of enzymes involved in flavonoid biosynthesis.     

Nitrogen balance and losses through drainage waters in an agricultural watershed of the Po Valley (Italy)

Sustainable agriculture requires assessments of nitrogen fluxes and monitoring of potential nitrate losses. Watershed studies are particularly valuable to calculate nitrogen balances and quantify the relative importance of different sources of inputs and outputs. A nitrogen balance was calculated from September 2004 to October 2006 in an agricultural watershed named Valle Volta (Northern Italy) located in a Nitrate Vulnerable Zone. The area, consisting of 17.4 km² of arable land, with limited presence of urban areas and roads, is entirely below the sea level (3 m b.s.l. in average). Soils are typically Vertic Cambisols and Thionic Fulvisols with fine texture (silty clay or silty clay loam). About 45% of the agricultural soil is pipe-drained. The ground water level is maintained at 4.6 m b.s.l. by the activity of pumps that raise excess waters into a river. Water fluxes in and out from the basin were daily registered, and dissolved inorganic nitrogen concentration (N–NO₃ + N–NH₄) analyzed periodically. Data about fertilizers applications, seeds and crop yield were obtained from farmers’ interviews. Biological nitrogen fixation (BNF) was estimated on the base of dry matter yield. Major N inputs derived from fertilizers (174–188 Mg watershed⁻¹ year⁻¹), followed by BNF (126–131 Mg watershed⁻¹ year⁻¹). Maize was the crop receiving the highest fertilization rates, accounting for more than 40% of total fertilizer inputs. Saleable products were the main form of N leaving the watershed (317–338 Mg watershed⁻¹ year⁻¹). Nitrate was the main N form in irrigation and efflux water; its concentration was higher from autumn to spring, with peaks of 10–20 mg N L⁻¹ in efflux water, while it was low in summer. Nitrogen losses with efflux water were higher in spring and in autumn. Overall, losses of nitrate by efflux water were limited if compared with literature data. Water balance in the area remained near zero at the beginning and the end of the first year, confirming the suitability of the area for this kind of study. The potential net contribution of each hectare of agricultural soil of Valle Volta basin to the N load toward the Adriatic sea is about 5.5 kg N. Our study demonstrated that in the Valle Volta watershed, total N outputs and inputs are of similar magnitude, indicating that crop management and especially N fertilization techniques has reached good levels of ecological sustainability.     

An updated checklist of plant agrobiodiversity of northern Italy

Genetic Resources and Crop Evolution - Northern Italy is an area particularly suitable for the cultivation of different crops. It used to be characterized by a high agrobiodiversity. However, it is...