Adapting Agriculture to Climate Change: A Synopsis of Coordinated National Crop Wild Relative Seed Collecting Programs across Five Continents

The Adapting Agriculture to Climate Change Project set out to improve the diversity, quantity, and accessibility of germplasm collections of crop wild relatives (CWR). Between 2013 and 2018, partners in 25 countries, heirs to the globetrotting legacy of Nikolai Vavilov, undertook seed collecting expeditions targeting CWR of 28 crops of global significance for agriculture. Here, we describe the implementation of the 25 national collecting programs and present the key results. A total of 4587 unique seed samples from at least 355 CWR taxa were collected, conserved ex situ, safety duplicated in national and international genebanks, and made available through the Multilateral System (MLS) of the International Treaty on Plant Genetic Resources for Food and Agriculture (Plant Treaty). Collections of CWR were made for all 28 targeted crops. Potato and eggplant were the most collected genepools, although the greatest number of primary genepool collections were made for rice. Overall, alfalfa, Bambara groundnut, grass pea and wheat were the genepools for which targets were best achieved. Several of the newly collected samples have already been used in pre-breeding programs to adapt crops to future challenges.info:eu-repo/semantics/publishedVersio

New Insight into the History of Domesticated Apple: Secondary Contribution of the European Wild Apple to the Genome of Cultivated Varieties

The apple is the most common and culturally important fruit crop of temperate areas. The elucidation of its origin and domestication history is therefore of great interest. The wild Central Asian species Malus sieversii has previously been identified as the main contributor to the genome of the cultivated apple (Malus domestica), on the basis of morphological, molecular, and historical evidence. The possible contribution of other wild species present along the Silk Route running from Asia to Western Europe remains a matter of debate, particularly with respect to the contribution of the European wild apple. We used microsatellite markers and an unprecedented large sampling of five Malus species throughout Eurasia (839 accessions from China to Spain) to show that multiple species have contributed to the genetic makeup of domesticated apples. The wild European crabapple M. sylvestris, in particular, was a major secondary contributor. Bidirectional gene flow between the domesticated apple and the European crabapple resulted in the current M. domestica being genetically more closely related to this species than to its Central Asian progenitor, M. sieversii. We found no evidence of a domestication bottleneck or clonal population structure in apples, despite the use of vegetative propagation by grafting. We show that the evolution of domesticated apples occurred over a long time period and involved more than one wild species. Our results support the view that self-incompatibility, a long lifespan, and cultural practices such as selection from open-pollinated seeds have facilitated introgression from wild relatives and the maintenance of genetic variation during domestication. This combination of processes may account for the diversification of several long-lived perennial crops, yielding domestication patterns different from those observed for annual species

Exploring Effective Conservation of Charismatic Flora: Orchids in Armenia as a Case Study

Plants are the bedrock of life on Earth but are increasingly threatened with extinction. The most cost-effective way of conserving plant diversity is through Protected Areas (PAs). However, the locality, size, and management of PAs are crucial for effectively maintaining diversity and have been criticized as currently inadequate. Using Armenia as our study site and orchids as our study taxa, we sought to (1) identify spatial patterns of orchid diversity hotspots and corresponding PA network sites; (2) examine if the current PA network is effective at capturing orchid species richness and diversity and (3) explore the relationship between the range of area suitability of species and level of protection. We used data collected from herbarium, field visits and GBIF occurrence records. Using freely available mapping software, we created heatmaps of observations and species richness. We compared PA sites based on the number of species (species richness) and diversity (Shannon–Weiner Index). Species range was developed using the MaxEnt model and a correlation analysis was performed against the proportion of the range within PA. We found that 57% of PA sites have a representation of at least one species of orchid, but some threatened species are not presented within any PA site. The Tavush and Syunik province not only held the highest species richness (>10 species), but the PA network within also held high orchid diversity (2.5 diversity index value for Dilijan National Park). We did not find a significant relationship between the range of area suitability for orchids and protection; however, all our target species had less than 30% of their range under protection. Our study highlights important challenges related to the limitations of available data, and we discuss these implications towards effective conservation outcomes for orchids for the region

Evidence of an additional center of apple domestication in Iran, with contributions from the Caucasian crab apple Malus orientalis Uglitzk. to the cultivated apple gene pool. Running head: Apple domestication in the Caucasus and Iran

International audienceDivergence processes in crop-wild fruit tree complexes in pivotal regions for plant domestication such as the Caucasus and Iran remain little studied. We investigated anthropogenic and natural divergence processes in apples in these regions using 26 microsatellite markers amplified in 550 wild and cultivated samples. We found two genetically distinct cultivated populations in Iran that are differentiated from Malus domestica, the standard cultivated apple worldwide. Coalescentbased inferences showed that these two cultivated populations originated from specific domestication events of Malus orientalis in Iran. We found evidence of substantial wild-crop and crop-crop gene flow in the Caucasus and Iran, as has been described in apple in Europe. In addition, we identified seven genetically differentiated populations of wild apple (M. orientalis), not introgressed by the cultivated apple. Niche modeling combined with genetic diversity estimates indicated that these wild populations likely resulted from range changes during past glaciations. This study identifies Iran as a key region in the domestication of apple and M. orientalis as an additional contributor to the cultivated apple gene pool. Domestication of the apple tree therefore involved multiple origins of domestication in different geographic locations and substantial cropwild hybridization, as found in other fruit trees. This study also highlights the impact of climate change on the natural divergence of a wild fruit tree and provides a starting point for apple conservation and breeding programs in the Caucasus and Iran

Relative posterior probabilities (<i>p</i>) for the four historical models compared using approximate Bayesian computations.

<p>Models are described in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1002703#pgen-1002703-g004" target="_blank">Figure 4</a>. CI2.5 and CI97.5 are boundaries of the 95% confidence intervals.</p

Proportions of ancestry in two ancestral genepools inferred with the STRUCTURE program, based on datasets including <i>M. domestica</i> (green, <i>N</i> = 299) and each of the four wild <i>Malus</i> species (red).

<p>The x-axis is not to scale (details in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1002703#pgen.1002703.s005" target="_blank">Table S2</a>).</p

Proportions of ancestry of <i>Malus</i> genotypes from five species (<i>N</i> = 770) from <i>K</i> = 2 to <i>K</i> = 8 ancestral genepools (“clusters”) inferred with the STRUCTURE program.

<p>Each individual is represented by a vertical bar, partitioned into <i>K</i> segments representing the amount of ancestry of its genome in <i>K</i> clusters. When several clustering solutions (“modes”) were represented within replicate runs, the proportion of simulations represented by each mode is given.</p