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We inoculated Tuber aestivum and Tuber sinoaestivum on Carya illinoinensis to explore the effects of inoculation on host plant growth, enzyme activities, the physicochemical properties of rhizosphere soil, the denitrifying bacterial community in the rhizosphere, and the distribution of mating type genes in the rhizosphere. We found that the Tuber spp. inoculation increased the height of the host plant and that the stem circumference of the host was greater two months after inoculation. Six months after inoculation, the peroxidase activity of the seedlings inoculated with T. sinoaestivum was higher than that of the control. At four and six months after inoculation, the superoxidase dismutase activities of the seedlings inoculated with T. aestivum were higher than those of the seedlings inoculated with T. sinoaestivum. Six months after inoculation, nitrate nitrogen content was lowest in the control and highest in the T. sinoaestivum treatment. Among the nirS-type denitrifying bacteria community, the relative abundances of Proteobacteria were high. T. aestivum and T. sinoaestivum inoculation did not affect the diversity of denitrifying bacteria. The mating type genes MAT1-1-1 and MAT1-2-1 were detected in the rhizosphere of C. illinoinensis inoculated with T. sinoaestivum and T. aestivum, and MAT1-1-1 dominated over MAT1-21. (c) 2021 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Our understanding of subsistence strategies, resources and lifeways of Finnish Iron Age populations remains incomplete despite archaeological, osteological, macrobotanical, and palynological investigations. This is due in part to poor preservation of organic macroremains in the acidic boreal sediments. To address this problem, here we present the first data from microscopic remains preserved in prehistoric dental calculus from Finland. We extracted and analysed both plant and animal microremains from human calculus and burial site sediment samples, originating from Luistari cemetery in southwestern Finland (samples from c. 600-1200 calAD). We recovered phytoliths, parasites, fibers and feathers. While in Finland few previous archaeological studies have investigated phytoliths, our study confirms the importance of these microremains for interpretating dietary patterns. It is also the first time that intestinal parasites have been reported in Finland. Our study demonstrates that, especially when working with acidic sediments typical for boreal environments, microremain studies can considerably increase the information value of archaeological samples, and that dental calculus and phytolith analysis are important new methods in the research of prehistorical lifestyles. This combined microremain analysis should be more broadly applied in contexts where other dietary records do not remain. (C) 2019 The Authors. Published by Elsevier Ltd.

Highlight Phs-A1 confers resistance to sprouting in wheat by delaying the rate of seed dormancy loss and is distinct from the previously proposed PM19 candidate genes., The precocious germination of cereal grains before harvest, also known as pre-harvest sprouting, is an important source of yield and quality loss in cereal production. Pre-harvest sprouting is a complex grain defect and is becoming an increasing challenge due to changing climate patterns. Resistance to sprouting is multi-genic, although a significant proportion of the sprouting variation in modern wheat cultivars is controlled by a few major quantitative trait loci, including Phs-A1 in chromosome arm 4AL. Despite its importance, little is known about the physiological basis and the gene(s) underlying this important locus. In this study, we characterized Phs-A1 and show that it confers resistance to sprouting damage by affecting the rate of dormancy loss during dry seed after-ripening. We show Phs-A1 to be effective even when seeds develop at low temperature (13 °C). Comparative analysis of syntenic Phs-A1 intervals in wheat and Brachypodium uncovered ten orthologous genes, including the Plasma Membrane 19 genes (PM19-A1 and PM19-A2) previously proposed as the main candidates for this locus. However, high-resolution fine-mapping in two bi-parental UK mapping populations delimited Phs-A1 to an interval 0.3 cM distal to the PM19 genes. This study suggests the possibility that more than one causal gene underlies this major pre-harvest sprouting locus. The information and resources reported in this study will help test this hypothesis across a wider set of germplasm and will be of importance for breeding more sprouting resilient wheat varieties.

In this study, the effect of different levels of nitrogen on bread wheat varieties was searched. Aiming this, four bread wheat varieties (Momtchil, Opata, Bandırma-97 and Pamukova-97) and nitrogen rates at five different levels [0 (control), 60, 120, 180, 240 kg N/ha] were experimented under the ecological conditions of Sakarya and Pamukova between 1995 and 1997. In this study, yield and spikes per m2, plant height, spike length, biomas at harvest, harvest index, 1000 grain weight and hectoliter weight which are the yield components of wheat were searched and the economic nitrogen levels were separately determined for each one of both varieties and ecological conditions. As a result, the most economic nitrogen levels were ranged 150 to 170 kg per ha in Sakarya and from 150 to 210 kg per ha in Pamukova., Bu çalışmada değişik azotlu gübre dozlarının ekmeklik (Triticum aestivum var. aestivum L.) buğday çeşitleri üzerindeki etkileri araştırılmıştır. Bu amaçla dört ekmeklik buğday çeşidi (Momtchil, Opata, Bandırma–97 ve Pamukova–97) ile beş değişik azot dozu [0 (kontrol), 6, 12, 18, 24 kg N/da] 1995–1997 yılları arasında Sakarya ve Pamukova koşullarında denemeye alınmıştır. Denemede verim ve verim unsurlarından m2'deki başak sayısı, bitki boyu, başak uzunluğu, saplı ağırlık, hasat indeksi, 1000 tane ağırlığı ve hektolitre ağırlığı incelenmiş; çeşitlerin her iki lokasyon için ekonomik azotlu gübre ihtiyaçları belirlenmiştir. En fazla net gelir hesabına göre çeşitlere gerekli saf azot miktarı Sakarya'da 15-17 kg/da N, Pamukova'da ise 15-21 kg/da N arasında değişmiştir.

Immature embryos of Triticum tauschii cultured on L2 medium with 30 g∙L−1maltose gave rise to compact and highly structured callus that readily regenerated shoots when transferred to MS medium supplemented with zeatin and indole-3-acetic acid. Two cell suspensions were initiated from the callus induced on L2 medium. An analysis of chromosome number in these cell suspensions after 3 months of culture showed that 95 and 75% of the cells had a normal complement. After 5 months, in both lines the majority of cells had chromosome complements of 2n = 13 and many of these aneuploid cells possessed a dicentric chromosome. C-banding indicated that the dicentric was often formed from chromosomes 2D and 5D. Fifty-six plants regenerated from callus were grown to maturity. Variation was observed in tiller number, flowering time, and seed-set; in two cases, the variation in early flowering was shown to be heritable. All the regenerants analysed had normal chromosome counts (2n = 2x = 14) and meiotic analyses of 35 plants revealed no obvious structural rearrangements.Key words: immature embryo culture, regeneration, chromosome, cell suspension, Triticum tauschii.

Sr2 is the only known durable, race non-specific adult plant stem rust resistance gene in wheat. The Sr2 gene was shown to be tightly linked to the leaf rust resistance gene Lr27 and to powdery mildew resistance. An analysis of recombinants and mutants suggests that a single gene on chromosome arm 3BS may be responsible for resistance to these three fungal pathogens. The resistance functions of the Sr2 locus are compared and contrasted with those of the adult plant resistance gene Lr34.

A study was carried out in 1998-1999 and 1999-2000 growing seasons with 7 different "durum wheat" genotypes under West Anatolia conditions. The correlations among plant height, grain number per spike, grain weight per spike, 1000 grain weight, test weight and grain yield as well as direct and indirect effects of those traits on the grain yield were investigated using Path analysis. Grain number per spike, 1000-grain weight, plant height and test weight had significant direct effect on grain yield. It was concluded that these characteristics could be important selection criteria in durum wheat breeding studies.

International audience; The production situation–injury profile paradigm can be used as a framework to assess the harmfulness of multiple-pest complexes in a changing agriculture. A mechanistic simulation model for wheat, WHEATPEST, was developed to incorporate drivers of (i) variable production situations and (ii) their related injury profiles. The model simulates the harmful effects of pathogens, pests, and weeds in a simple, open, generic manner. Simulation drivers were derived from published reports, in particular through a meta-analysis of highly detailed farmers’ field surveys in the United Kingdom and the Netherlands. Preliminary analysis of the model’s performances indicates that WHEATPEST conforms with available published reports in a range of production situations and injury profiles. While improvement on some components of the model are discussed, this work points at the need for the collection of cross-disciplinary, reasonably accurate, and standardised data at a system’s level, and at the usefulness of modelling tools for basic research and policy.

Southern-blot hybridizations of total DNA to mitochondrial DNA (mtDNA) probes were used to investigate the extent of mtDNA variability in cultures derived from immature embryos of diploid (Triticum monococcum, genomic formula: AA, T. tauschii, genomic formula: DD), allotetraploid (T. durum cv ''Creso'', genomic formula: AABB). and allohexaploid (T. aestivum, genomic formula: AABBDD) wheat species. Similar distinct changes in mtDNA organization were observed in in vitro cultures of the derived tetraploid and the hexaploid species with related genomes. The tetraploid and hexaploid species share the B genome and mtDNA variability in in vitro culture is known to be under nuclear control. These results suggest that a study of B genome diploids and other polyploid combinations would now shed light on whether or not mtDNA variability in tissue cultures is under B-genome control.

Bu çalışmada değişik azotlu gübre dozlarıma ekmeklik (Triticum aestivum var. aestivum L.) buğday çeşitleri üzerindeki etkileri araştırılmıştır. Bu amaçla beş ekmeklik buğday çeşit ve hattı (Öthalom ile Momtchil çeşitleri ve tescile aday üç hat) ile beş değişik azot dozu [0 (kontrol), 5, 10, 15, 20 kg N/da] 1994 yılında Sakarya koşullarında denemeye alınmıştır. Azot dozunun başak uzunluğu, m2'deki başak sayısı, bitki basma başak sayısı, başaklanma gün sayısı, saplı ağırlık, yatma, hasat indeksi, 1000 tane ağrılığı ve m2'deki tane verimi üzerine etkisi önemli bulunmuştur. Çeşitler ise bitki boyu, başak uzunluğu, başakta başakcık sayısı, başakta tane sayısı, başakta tane ağrılığı m2'deki bitki sayısı, bitki basma başak sayısı, başaklanma gün sayısı, saplı ağırlık, yatma, hasat indeksi, 1000 tane ağırlığı ve hektolitre ağırlığı yönünden farklılık göstermişlerdir. Çeşit ile azot dozu interaksiyonu ise bitki boyu, başakta tane ağırlığı, başaklanma gün sayısı ve 1000 tane ağırlığı üzerine önemli etkide bulunmuştur.ANAHTAR KELİMELER: Triticum, aestivum, Triticum aestivum, azot, azot dozu, azotlu gübre, buğday, ekmeklik buğday, verim öğeleri, yatma. In this study, the effect of nitrogen fertilisers at different levels an bread, wheat varieties has been searched. Aiming at this, five bread wheat varieties and breeding materials (Öthalom and Momtchil varieties and three breeding materials submitted to official registration) and nitrogen at five different levels [0 (control), 5, 10, 15, 20 kg N/da] have been experimented under the ecological conditions of Sakarya province in 1994. It was found that the effect of nitrogen level on spike length, spikes per m2, spikes per plant, days to heading, biomas at harvest, lodging, harvest index, 1000-gram weight and grain yield per m2 was significantly important. On the other hand, the varieties shown some differences about at plant height, spike length, spikelets per spike, grains per spike, grain weight per spike, plants per m2, spikes per plant, days to heading, biomas at harvest, lodging harvest index, 1000-grain weight and hectolitre weight Plant height, grain weight per spike, days to heading and 1000-grain weight were significantly affected by die interaction of variety with nitrogen levelKEY WORDS: Triticum, aestivum, TrMcum aestivum, nitrogen, nitrogen fertiliser, nitrogen level, wheat, bread wheat, yield component, lodging. 73

Background Costs of adaptation play an important role in host-parasite coevolution. For parasites, evolving the ability to circumvent host resistance may trade off with subsequent growth or transmission. Such costs of virulence (sensu plant pathology) limit the spread of all-infectious genotypes and thus facilitate the maintenance of genetic polymorphism in both host and parasite. We investigated costs of three virulence factors in Puccinia striiformis f.sp.tritici, a fungal pathogen of wheat (Triticum aestivum). Results In pairwise competition experiments, we compared the fitness of near-isogenic genotypes that differed by a single virulence factor. Two virulence factors (vir4, vir6) imposed substantial fitness costs in the absence of the corresponding resistance genes. In contrast, the vir9 virulence factor conferred a strong competitive advantage to several isolates, and this for different host cultivars and growing seasons. In part, the experimentally derived fitness costs and benefits are consistent with frequency changes of these virulence factors in the French pathogen population. Conclusion Our results illustrate the variation in the evolutionary trajectories of virulence mutations and the potential role of compensatory mutations. Anticipation of such variable evolutionary outcomes represents a major challenge for plant breeding strategies. More generally, we believe that agro-patho-systems can provide valuable insight in (co)evolutionary processes in host-parasite systems.

Chromosomal location of resistance to Mycosphaerella graminicola was studied in substitution lines of resistant Triticum genotypes into the (susceptible) cultivar Chinese Spring (T. aestivum). (Moderately) resistant genotypes for which substitution lines were available were tested in a first screening. We selected a synthetic hexaploid wheat (Synthetic 6x; T. dicoccoides × T. tauschii), T. spelta and the wheat (T. aestivum) cultivars Cheyenne and Cappelle-Desprez. In a second screening the most suitable Argentinian isolates were identified. We decided to use the isolate IPO 92067 (all sets of substitution lines), IPO 93014 (substitution lines of Synthetic 6x, Cappelle-Desprez and T. spelta) and IPO 92064 (substitution lines of Cheyenne). In the final experiments, substitution lines of the selected genotypes into Chinese Spring were grown in two different environments and inoculated with the selected isolates at the seedling stage (lines of all four selected genotypes) or the adult stage (lines of Synthetic 6x and Cheyenne). Resistance was expressed as (reduction in) necrosis percentage or pycnidial coverage percentage; the two measures were highly (linearly) correlated. When tested in the seedling stage, all chromosomes seemed to carry genes effective against M. graminicola. Many genes were effective against only one isolate or in only one environment or their effects only showed in one resistance parameter. Often these effects were minor. Only chromosome 7D of Synthetic 6x was found with a major effect against both isolates tested. When tested in the adult stage, all lines but the one carrying chromosome 4B from the resistant parent seemed to show genes effective against M. graminicola. The line carrying chromosome 7D from Synthetic 6x showed a level of resistance similar to the resistant parent for isolate IPO 92067, but not for isolate IPO 93014. Major genes, effective against both isolates, were also found on chromosomes 5A and 5D from Synthetic 6x. Lines carrying chromosome 1B, 5D or 6D from Cheyenne showed major effects against isolate IPO 92064. For both necrosis percentage and pycnidial coverage percentage, highly significant linear correlations were found between resistance in the seedling stage and resistance in the adult stage. However, the variance accounted for was only small (20-24%; n = 184)., Facultad de Ciencias Agrarias y Forestales