The “when”, the “where” and the “why” of the Neolithic revolution in the Levant

An accumulation of data concerning the domestication of plants and the refinement of research questions in the last decade have enabled us a new look at the Neolithic Revolution and Neolithization processes in the Levant. This paper raises some points concerning the “When” and “Where” of plant domestication and suggests that the origins of plant domestication were in a welldefined region in southeast Turkey and north Syria. It presents a view on the process of Neolithization in the Levant and offers some comments concerning the background and motivations behind the Neolithic Revolution.Naraščanje količine podatkov o udomačitvi rastlin in vedno bolj natančna vprašanja raziskovalcev so v zadnjem desetletju omogočili, da na novo ovrednotimo neolitsko revolucijo in proces neolitizacije v Levantu. V članku izpostavljamo nekatere vidike “časa” in “kraja” udomačitve rastlin ter menimo, da je bil izvor udomačitve rastlin na jasno omejenem območju jugovzhodne Turčije in severne Sirije. Predstavimo pogled na proces neolitizacije v Levantu in nekoliko pojasnimo družbeno okolje in motive za neolitsko revolucijo

Genetic analysis of wheat domestication and evolution under domestication

Wheat is undoubtedly one of the world's major food sources since the dawn of Near Eastern agriculture and up to the present day. Morphological, physiological, and genetic modifications involved in domestication and subsequent evolution under domestication were investigated in a tetraploid recombinant inbred line population, derived from a cross between durum wheat and its immediate progenitor wild emmer wheat. Experimental data were used to test previous assumptions regarding a protracted domestication process. The brittle rachis (Br) spike, thought to be a primary characteristic of domestication, was mapped to chromosome 2A as a single gene, suggesting, in light of previously reported Br loci (homoeologous group 3), a complex genetic model involved in spike brittleness. Twenty-seven quantitative trait loci (QTLs) conferring threshability and yield components (kernel size and number of kernels per spike) were mapped. The large number of QTLs detected in this and other studies suggests that following domestication, wheat evolutionary processes involved many genomic changes. The Br gene did not show either genetic (co-localization with QTLs) or phenotypic association with threshability or yield components, suggesting independence of the respective loci. It is argued here that changes in spike threshability and agronomic traits (e.g. yield and its components) are the outcome of plant evolution under domestication, rather than the result of a protracted domestication process. Revealing the genomic basis of wheat domestication and evolution under domestication, and clarifying their inter-relationships, will improve our understanding of wheat biology and contribute to further crop improvement

Genetic Relationship in Cicer Sp. Expose Evidence for Geneflow between the Cultigen and Its Wild Progenitor

There is a debate concerning mono- or poly-phyletic origins of the Near Eastern crops. In parallel, some authors claim that domestication was not possible within the natural range of the wild progenitors due to wild alleles flow into the nascent crops. Here we address both, the mono- or poly-phyletic origins and the domestications within or without the natural range of the progenitor, debates in order to understand the relationship between domesticated chickpea (Cicer arietinum L.) and its wild progenitor (C. reticulatum Ladizinsky) with special emphasis on its domestication centre in southeastern Turkey. A set of 103 chickpea cultivars and landraces from the major growing regions alongside wild accessions (C. reticulatum, C. echinospermum P.H Davis and C. bijugum K.H. Rech) sampled across the natural distribution range in eastern Turkey were genotyped with 194 SNPs markers. The genetic affinities between and within the studied taxa were assessed. The analysis suggests a mono-phyletic origin of the cultigen, with several wild accession as likely members of the wild stock of the cultigen. Clear separation between the wild and domesticated germplasm was apparent, with negligible level of admixture. A single C. reticulatum accession shows morphological and allelic signatures of admixture, a likely result of introgression. No evidence of geneflow from the wild into domesticated germplasm was found. The traditional farming systems of southeaster Turkey are characterized by occurrence of sympatric wild progenitor-domesticated forms of chickpea (and likewise cereals and other grain legumes). Therefore, both the authentic crop landraces and the wild populations native to the area are a unique genetic resource. Our results grant support to the notion of domestication within the natural distribution range of the wild progenitor, suggesting that the Neolithic domesticators were fully capable of selecting the desired phenotypes even when facing rare wild-domesticated introgression events

Experimental harvesting of wild peas in Israel: implications for the origins of near east farming

Abstract Previous evaluations of the potential advantage of farming over foraging have been based on experimental harvesting of wild cereals in Near Eastern ecosystems. The highly successful combination of cereals and legumes, ''the Near Eastern crops assemblage'', is considered a natural choice due to the complementary nutritional value of the two crop types. Yet, legumes were rarely referred to in models describing early farming and the transition from foraging to farming. Wild legumes differ from wild cereals in several attributes pertaining to domestication, including population density (patchy vs. dense), growth habit (indeterminate vs. determinate), dispersal units (camouflaged seeds vs. awned spikelets), seed dormancy (90e80% vs. 50%), and year to year establishment (erratic vs. regular). We have analyzed the yield potential of three wild pea species (Pisum elatius, P. humile, and P. fulvum) in several ecosystems in Israel. All three pea species have patchy distribution patterns and the yield potential of the wild populations is highly variable. A harvest rate of 0.6e610 grams (calculated per collector) of clean dry grain per hour of harvest time was estimated. Among the three species studied the one adopted for domestication appears to be the least productive. This suggests that the potential productivity of wild peas was not the only or even the major consideration for domestication

Drought response and genetic diversity in <em>Pisum fulvum</em>, a wild relative of domesticated pea

International audienceProductivity of grain crops in semi-arid areas is often affected by drought, which is likely to increase due to climate changes. A collection of 160 wild pea (Pisum fulvum, Pf) accessions was assembled from across its ecological range in Israel (350-850 mm annual precipitation) and used to assess genetic diversity in this taxon. A range of penology and other morpho-physiological traits was documented. We hypothesized that native species evolving under east Mediterranean climate carry adaptive traits to cope with drought stress. Accessions were classified according to SNP variation and habitat ecogeography. Significant differences were found between accession groups, but grouping in both systems did not match. Fifty-two Pf accessions and 3 domesticated (Pisum sativum) genotypes were evaluated, during two seasons, under well-watered (600mm) and water-limited (350mm) conditions. Total dry matter, grain yield, harvest index and average grain weight were higher in domesticated pea than wild Pf, however several Pf accessions exhibited lower drought susceptibility indices (i.e. greater stability across environments) than domesticated pea. Of special interest were a number of Pf genotypes in which low susceptibility to water stress was coupled with relatively high productivity. Sampling habitats of the low susceptibility - high productivity accessions are not the driest ones but are rather characterized by mild (400-530mm) annual precipitation. Further sampling and evaluation of Pf from such locations may improve our understanding of pea drought adaptation and yield physiology

Seed size is associated with sucrose synthase activity in developing cotyledons of chickpea

International audienceSeed size, a key quality determinant in the marketing of the cool-season food legume chickpea (Cicer arietinum L.), can be reduced under terminal drought. Sucrose synthase and invertase, important enzymes in sugar metabolism, play an important role in seed filling. This study aimed to determine whether these enzymes in the developing cotyledons are associated with the final seed size of chickpea by following their level of activity during seed filling in large- and small-seeded chickpea genotypes. The level of invertase in the cotyledons was unchanged during seed filling, but sucrose synthase reached a maximum about 500 to 600 growing degree days (GDD) after flowering when cell numbers were no longer increasing, but the cotyledons were increasing rapidly in dry weight. In a range of genotypes differing in seed size, the level of sucrose synthase activity in the developing cotyledons at 500 to 600 GDD was correlated with the final seed size at maturity when measured at a rainfed site in two different years. The level of activity of sucrose synthase at the same stage of development in F(2), F(3), and F(7) populations of crosses between a large-seeded cultivar and two small-seeded genotypes was also correlated with final seed size. It is concluded that sucrose synthase, but not invertase, in developing cotyledons is the key enzyme influencing seed size in chickpea

In-Field Comparative Study of Landraces vs. Modern Wheat Genotypes under a Mediterranean Climate

The Near East climate ranges from arid to a Mediterranean, under which local wheat landraces have been grown for over millennia, assumingly accumulating a unique repertoire of genetic adaptations. In the current study, we subjected a subset of the Israeli Palestinian Landraces (IPLR) collection (n = 19: durum and bread wheat landraces, modern wheat cultivars, and landraces mixtures) to full-field evaluation. The multifield experiment included a semiarid site (2018&ndash;2019, 2019&ndash;2020) under low (L) and high (H) supplementary irrigation, and a Mediterranean site (2019&ndash;2020). Water availability had a major impact on crop performance. This was reflected in a strong discrimination between environments for biomass productivity and yield components. Compared to landraces, modern cultivars exhibited significantly higher grain yield (GY) across environments (+102%) reflecting the effect of the Green Revolution. However, under the Gilat19 (L) environment, this productivity gap was significantly reduced (only +39%). Five excelling landraces and the durum mix exhibited good agronomic potential across all trails. This was expressed in relatively high GY (2.3&ndash;2.85 t ha&minus;1), early phenology (86&ndash;96 days to heading) and lodging resistance. Given the growing interest of stakeholders and consumers, these might be considered future candidates for the local artisanal wheat grain market. Yet, this step should be taken only after establishing an adjustable field management protocol