Modern Cultivars Research Articles

Nodule occupancy of effective rhizobia vary between historical and modern cultivars of white clover

ABSTRACT The ability of plants to select effective symbiotic partners is crucial for optimum plant growth. In New Zealand, breeding programmes for white clover (Trifolium repens) have made selections largely based on above-ground characteristics, with little direct attention given to the ability of cultivars to form effective below-ground associations. The ability of three pairs of historical (1930s–1950s), and modern (2000s) cultivars of white clover, to form associations with effective strains of Rhizobium leguminosarum (rhizobia) from a mixture of strains was tested in vitro. First, the efficacy of six individual strains of rhizobia was ranked against all six clover cultivars with shoot biomass used as a direct measure of symbiotic effectiveness for each strain × cultivar combination. Next, each cultivar was inoculated with a mixture of all rhizobia strains at the same cell concentration to examine the identity and frequency of strains found on each host. There was a positive relationship between nodule occupancy and strain effectiveness for historical but not modern cultivars. Cultivars Grasslands Huia and Louisiana (both historical) had nodule occupancy increase with strain effectiveness. This study provides some evidence that historical cultivars may be better able to form associations with effective strains of rhizobia compared with modern cultivars.

The complex polyploid genome architecture of sugarcane

Sugarcane, the world’s most harvested crop by tonnage, has shaped global history, trade and geopolitics, and is currently responsible for 80% of sugar production worldwide1. While traditional sugarcane breeding methods have effectively generated cultivars adapted to new environments and pathogens, sugar yield improvements have recently plateaued2. The cessation of yield gains may be due to limited genetic diversity within breeding populations, long breeding cycles and the complexity of its genome, the latter preventing breeders from taking advantage of the recent explosion of whole-genome sequencing that has benefited many other crops. Thus, modern sugarcane hybrids are the last remaining major crop without a reference-quality genome. Here we take a major step towards advancing sugarcane biotechnology by generating a polyploid reference genome for R570, a typical modern cultivar derived from interspecific hybridization between the domesticated species (Saccharum officinarum) and the wild species (Saccharum spontaneum). In contrast to the existing single haplotype (‘monoploid’) representation of R570, our 8.7 billion base assembly contains a complete representation of unique DNA sequences across the approximately 12 chromosome copies in this polyploid genome. Using this highly contiguous genome assembly, we filled a previously unsized gap within an R570 physical genetic map to describe the likely causal genes underlying the single-copy Bru1 brown rust resistance locus. This polyploid genome assembly with fine-grain descriptions of genome architecture and molecular targets for biotechnology will help accelerate molecular and transgenic breeding and adaptation of sugarcane to future environmental conditions.

Enhancing Agrobiodiversity: Designing an In Vitro Screening Protocol for Solanum lycopersicum L. and Solanum pimpinellifolium L. to Explore Responses to Salinity Stress

The foremost cause behind worldwide crop losses is attributed to abiotic stresses. Among them, salinity is a major concern for agriculture and is expected to play an increasingly important role as rising food demands and climate changes will inevitably lead to the greater use of marginal lands and poor-quality irrigation water. Tomato is a moderately salinity-sensitive crop which is widely used in the presence of poor-quality irrigation water without manifesting yield reduction. However, the excessive accumulation of salts can reduce photosynthetic efficiency, unbalance nutrient assimilation, reduce growth, and reduce product quality. This study was undertaken to explore the response of some varieties of Solanum lycopersicum that could be used as model systems to evaluate the performance of wild tomato ecotypes in future studies to identify genetic resources that respond adequately to climate change in the Mediterranean area. Tomato seedlings were raised in vitro on plates with sucrose-free agarized medium containing increasing concentrations of sea salt. The autotrophic conditions enabled a response resembling the plant’s behavior in vivo. The obtained results identified an interesting variety that can be used as a model for modern cultivars and concentrations, from which the behavior of some Solanum spp. can be further investigated.

Fertilizer regime and cultivar affect barley growth and rhizobiome composition

To combat climate change and environmental pollution, agriculture must reduce mineral fertilizer use and adopt sustainable, low-input, and organic practices. In such systems, plants depend on the soil microbiome for nutrient acquisition and growth. Thus, enhancing plant-microbiome interactions is vital for maintaining or even increasing production sustainably. Modern plant breeding has led to barley cultivars that yield high under substantial mineral fertilizer application. However, this selective breeding may have diminished traits essential for plant-microbiome interactions, making these cultivars less suitable for sustainable agriculture. In contrast, older cultivars might have preserved traits from their common wild ancestor, enabling them to prosper under low nutrient conditions. This study evaluated four modern elite barley cultivars and three older (pre-1980). Grown under various fertilizer regimes, we assessed their root microbiome using 16S rRNA amplicon sequencing. Our objectives were: i) to determine the impact of nutrient availability on plant nutrient uptake and biomass production, and ii) to understand how the time since domestication (domestication age), individual cultivar, and fertilizer regime influence the root microbiome. We found that without fertilizer, old cultivars had superior biomass production and higher leaf concentrations of nitrogen, potassium, sulfur, iron, zinc, and copper than modern cultivars. This indicates that older barley cultivars may have retained their wild ancestors' capability to synergize with the soil microbiome, enhancing nutrient acquisition in low-input systems. Notably, the diversity of the rhizo-microbiome was not significantly affected by domestication age but varied with individual cultivar and fertilizer treatment.

Improving rotational partners: Intraspecies variation for pea cover cropping traits

AbstractTo improve cover crops such as peas (Pisum sativum), as rotational partners, intraspecific variation for cover cropping traits such as nutrient mobilization, carbon deposition, and beneficial microbial recruitment must be identified. The majority of research on cover crops has focused on interspecies comparisons for cover cropping variation with minimal research investigating intraspecies variation. To address if variation of cover cropping traits is present within a cover cropping species, we grew 15 diverse accessions (four modern cultivars, three landraces, and eight wild accessions) of pea in a certified organic setting. We measured various cover cropping traits, such as nutrient mobilization, soil organic matter deposition, and microbial recruitment, and quantified the effect of pea accession on the growth and yield of a subsequently planted crop of corn (Zea mays). We discovered that the domestication history of pea has a significant impact on soil properties. Specifically, domesticated peas (modern cultivars and landraces) had higher average plant–soil feedback values for amounts of nitrogen, carbon, and manganese compared to wild peas. Additionally, no variation for prokaryotic recruitment (α‐ and β‐diversity) was observed within pea; however, we did observe significant variation for fungal recruitment (α‐ and β‐diversity) due to domestication and accession. Our results demonstrate that there is variation present in peas, and likely all crops, that can be selected to improve them as rotational partners to ultimately boost crop yields in sustainable agroecosystems.

Unraveling root and rhizosphere traits in temperate maize landraces and modern cultivars: Implications for soil resource acquisition and drought adaptation.

A holistic understanding of plant strategies to acquire soil resources is pivotal in achieving sustainable food security. However, we lack knowledge about variety-specific root and rhizosphere traits for resource acquisition, their plasticity and adaptation to drought. We conducted a greenhouse experiment to phenotype root and rhizosphere traits (mean root diameter [Root D], specific root length [SRL], root tissue density, root nitrogen content, specific rhizosheath mass [SRM], arbuscular mycorrhizal fungi [AMF] colonization) of 16 landraces and 22 modern cultivars of temperate maize (Zea mays L.). Our results demonstrate that landraces and modern cultivars diverge in their root and rhizosphere traits. Although landraces follow a 'do-it-yourself' strategy with high SRLs, modern cultivars exhibit an 'outsourcing' strategy with increased mean Root Ds and a tendency towards increased root colonization by AMF. We further identified that SRM indicates an 'outsourcing' strategy. Additionally, landraces were more drought-responsive compared to modern cultivars based on multitrait response indices. We suggest that breeding leads to distinct resource acquisition strategies between temperate maize varieties. Future breeding efforts should increasingly target root and rhizosphere economics, with SRM serving as a valuable proxy for identifying varieties employing an outsourcing resource acquisition strategy.

Combined genome and transcriptome analysis of elite fiber quality in Gossypium barbadense.

Gossypium barbadense, which is one of several species of cotton, is well-known for its superior fiber quality. However, the genetic basis of its high-quality fiber remains largely unexplored. Here, we re-sequenced 269 G. barbadense accessions. Phylogenetic structure analysis showed that the set of accessions were clustered into three groups, G1 and G2 mainly included modern cultivars from Xinjiang, China, and G3 was related to widely introduced accessions in different regions worldwide. A genome-wide association study of five fiber quality traits across multiple field environments identified a total of 512 qtls (main effect QTLs) and 94 qtlEs (QTL-by-environment interactions) related to fiber quality, of which 292 qtls and 57 qtlEs co-located with previous studies. We extracted the genes located in these loci and performed expression comparison, local association analysis, and introgression segment identification. The results showed that high expression of hormone-related genes during fiber development, introgressions from G. hirsutum, and the recombination of domesticated elite allelic variation, were three major contributors to improve fiber quality of G. barbadense. In total, 839 candidate genes with encoding region variation associated with elite fiber quality were mined. We confirmed that haplotype GB_D03G0092H traced from G. hirsutum introgression, with a 1-bp deletion leading to a frameshift mutation compared with GB_D03G0092B, significantly improved fiber quality. GB_D03G0092H localized in the plasma membrane, while GB_D03G0092B in both the nucleus and plasma membrane. Overexpression of GB_D03G0092H in Arabidopsis (Arabidopsis thaliana) significantly improved the elongation of longitudinal cells. Our study systematically reveals the genetic basis of the superior fiber quality of G. barbadense and provides elite segments and gene resources for breeding high-quality cotton cultivars.

Comprehensive phenotypic evaluation by fruit quality traits and analysis of the genetic diversity of promising elite walnut forms bred in the North Caucasian Federal Scientific Center of Horticulture, Viticulture, and Winemaking

Walnuts are a source of benefi cial nutrients (fatty acids, vitamins, phenolic compounds) and are high in calories. In the breeding of this cultivated plant, one of the key areas is selection for fruit quality. A modern cultivar must meet the standards of fruit appearance (large fruit, light kernel color, round shape, easy shell-kernel separation). The study of the genetic structure of walnut collections using microsatellite markers is no less relevant. The article aims to comprehensively evaluate the economically valuable traits of fruits and analyze the genetic diversity of promising elite walnut forms bred by the North Caucasian Federal Scientific Center of Horticulture, Viticulture, and Winemaking employing microsatellite DNA markers. Morphological fruit evaluation was carried out according to 13 traits. The biochemical analysis included total fat content, phenolic compounds, macronutrients (Na, K, Mg, Ca), and water-soluble solids. The molecular genetic analysis was performed using eight SSR markers: WGA001, WGA069, WGA376, WGA276, WGA009, WGA202, WGA089, WGA321. The comprehensive phenotypic and biochemical evaluation of fruits resulted in the identifi cation of elite forms superior to the check cultivar. For these elite forms, the fruit weight was 17-1-18 (13.36 g), MP-82 (14.80 g), YaB-18 (13.47 g); the kernel content was 17-2-23 (61.24 %), 17-5-5 (58.49 %), 17-2-16 (57.7 %); the fat content – MP-34 (68 %), 17-1-18 (61 %), 17-2-16 (62 %), MP-39 (60 %), YaB-5 (60 %). The microsatellite analysis revealed an average allele value per locus of 7.13, which indicates a high level of genetic heterogeneity in the studied sample of elite forms. Using the UPGMA clustering method and PCoA analysis, we revealed the presence of two genetically distinct groups. Th e first one includes large-fruited samples that exceed the check cultivar in terms of fruit weight (MP-82, YaB-18). In the second group, high-oil-bearing forms with a large percentage of kernel yield (17-1-18, YaB-5, 17-2-23, 17-2-16, MP-39, MP-34, 17-5-5) and forms with good shell-kernel separation (17-2-5, 17-2-16, 17-5-5, 17-5-10, MP-39, MP-67, MP-69, MP-170) predominated. Th us, it can be concluded that crossing genetically distant forms is promising not only for solving breeding issues, but also for preserving and increasing the genetic heterogeneity of the breeding walnut gene pool.

A new winter wheat genetic resource harbors untapped diversity from synthetic hexaploid wheat

Key messageThe NIAB_WW_SHW_NAM population, a large nested association mapping panel, is a useful resource for mapping QTL from synthetic hexaploid wheat that can improve modern elite wheat cultivars.The allelic richness harbored in progenitors of hexaploid bread wheat (Triticum aestivum L.) is a useful resource for addressing the genetic diversity bottleneck in modern cultivars. Synthetic hexaploid wheat (SHW) is created through resynthesis of the hybridisation events between the tetraploid (Triticum turgidum subsp. durum Desf.) and diploid (Aegilops tauschii Coss.) bread wheat progenitors. We developed a large and diverse winter wheat nested association mapping (NAM) population (termed the NIAB_WW_SHW_NAM) consisting of 3241 genotypes derived from 54 nested back-cross 1 (BC1) populations, each formed via back-crossing a different primary SHW into the UK winter wheat cultivar ‘Robigus’. The primary SHW lines were created using 15 T. durum donors and 47 Ae. tauschii accessions that spanned the lineages and geographical range of the species. Primary SHW parents were typically earlier flowering, taller and showed better resistance to yellow rust infection (Yr) than ‘Robigus’. The NIAB_WW_SHW_NAM population was genotyped using a single nucleotide polymorphism (SNP) array and 27 quantitative trait loci (QTLs) were detected for flowering time, plant height and Yr resistance. Across multiple field trials, a QTL for Yr resistance was found on chromosome 4D that corresponded to the Yr28 resistance gene previously reported in other SHW lines. These results demonstrate the value of the NIAB_WW_SHW_NAM population for genetic mapping and provide the first evidence of Yr28 working in current UK environments and genetic backgrounds. These examples, coupled with the evidence of commercial wheat breeders selecting promising genotypes, highlight the potential value of the NIAB_WW_SHW_NAM to variety improvement.

Fhb9, a major QTL for Fusarium head blight resistance improvement in wheat

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, is one of the most devastating diseases of wheat worldwide. Identification and validation of major quantitative trait loci (QTLs) for FHB resistance without negative effects on agronomic traits is critical to success in breeding FHB-resistant cultivars. In this study, a stable major QTL on chromosome arm 2DL was identified by evaluating a recombinant inbred line (RIL) population derived from Shi4185×Shijiazhuang 8 in both field and greenhouse experiments. QTL mapping and pedigree analyses indicated that the 2DL QTL is the same QTL as QFhb-2DL previously identified in Ji5265, therefore, designated Fhb9. Four kompetitive amplicon sequence polymorphism (KASP) markers were developed based on exome capture sequencing data to enhance marker density in the Fhb9 region, and it was delimited to an interval between single nucleotide polymorphism (SNP) markers KASP-12056 (533.8) and KASP-525 (525.9 Mb) explained 26.0-30.1% of the phenotypic variation. Analysis of the geographic distribution of the Fhb9 resistance allele suggested that it originated from Huang-Huai winter wheat region in China, and very low frequency of Fhb9 in modern Chinese cultivars reveals that it has not been widely deployed in breeding programs. Field and greenhouse evaluation of yield-related traits of near-isogenic lines (NILs) contrasting in Fhb9 alleles indicated that Fhb9 resistance allele did not show any adverse effects on those traits. Fhb9 showed an additive effect on enhancing FHB resistance with Fhb1. Therefore, Fhb9 is a valuable major QTL for improving FHB resistance in wheat and the near-diagnostic markers developed in this study will facilitate its deployment in wheat breeding programs.

Agronomic performance and fruit sensory and quality analyses of pineapple cultivars

The objective of this study was to assess the agronomic performance and fruit sensory and quality characteristics in traditional and modern pineapple cultivars grown in Tangara da Serra, MT, Brazil. The experiment was conducted in a randomized block design, with five replications and 20 plants per plot. Planting was carried out in double rows with spacing of 1.2×0.4×0.4 m, in May 2018. The evaluated cultivars were BRS-Ajuba, BRS-Imperial, BRS-Vitoria, Gigante-de-Tarauaca, IAC-Fantastico, Jupi, Perola, and Smooth-Cayenne. Gigante-de-Tarauaca exhibited the highest fruit weight but presented low soluble solids content and soluble solids to titratable acidity ratio (SS/TA); thus, it is not recommended for fresh fruit market. Jupi exhibited fruit weights (>1500 g) suitable for the market and soluble solids above 12 °Brix, but SS/TA below 20. Considering the modern cultivars, BRS-Ajuba presented the highest fruit weight, but BRS-Imperial and IAC-Fantastico were the most attractive to consumers, as well as the traditional cultivar Perola. However, BRS-Imperial and IAC-Fantastico yield small fruits, which reduces their per-unit value in the market, as pineapples are typically valued based on their sizes.

Eco-Geographical and Botanical Patterns of Resistance to Lepidoptera Insects in Brassica rapa L.

In the context of the widespread expansion of damage by herbivorous pests of Brassica crops, taking into account the requirements for minimizing pesticide pollution of the environment, it is important to have fundamental knowledge of the geographical features of the distribution of pests and about the botanical confinement of plant resistance in order to develop a strategy for creating new Brassica cultivars with complex resistance to insects. The relevance of our work is related to the study of the variability in the degree of resistance of the extensive genetic diversity of Brassica rapa accessions to the main herbivorous pests of Brassica crops in contrasting ecological and geographical zones of the Russian Federation (Arctic, northwestern, and southern zones). We have studied the distribution and food preferences of Lepidoptera insects (diamondback moth Plutella xylostella and cabbage moth Mamestra brassicae) on a set of 100 accessions from the VIR B. rapa collection (Chinese cabbage, pakchoi, wutacai, zicaitai, mizuna, and leaf and root turnips) in the field in three zones of the Russian Federation. We have found that the diamondback moth and cabbage moth are largely harmful in three zones of the European part of the Russian Federation, although the degree of damage to plants by these insects varies by year of cultivation. On average, for the set studied during the two years of the experiment, the degree of plant damage by both pests in the Arctic zone was low and almost low, and in the northwestern and southern zones, it was medium. It was noted that diamondback moth damage was greater in the northwestern zone in both years and in the southern and Arctic zones in 2021, while in 2022, the degree of cabbage moth damage was slightly higher in the southern and Arctic zones. Under the conditions of field diamondback moth damage, the accessions of Chinese cabbage, wutacai, and mizuna turned out to be the most resistant (the damage score was 1.92-1.99), whereas the accessions of wutacai and pakchoi were the most resistant to the cabbage moth (the damage score was 1.62-1.78). A high variability in the degree of resistance of Brassica crops to Lepidoptera insects from complete resistance to susceptibility was revealed. We have identified sources of resistance to insects, including complex resistance in all study areas, among landraces and some modern cultivars of Chinese cabbage, pakchoi, wutacai, and mizuna from Japan and China, as well as European turnips. The highest susceptibility to pests in the studied set was noted in the accession of root turnip "Hinona" (k-1422, USA) (average damage score of 3.24-3.53 points). We were not able to establish the morphological features of resistant plants or the geographical confinement of the origin of resistance of B. rapa crop accessions.

Exploring SoySNP50K and USDA Germplasm Collection Data to Find New QTLs Associated with Protein and Oil Content in Brazilian Genotypes.

Genetic diversity within a germplasm collection plays a vital role in the success of breeding programs. However, comprehending this diversity and identifying accessions with desirable traits pose significant challenges. This study utilized publicly available data to investigate SNP markers associated with protein and oil content in Brazilian soybeans. Through this research, twenty-two new QTLs (Quantitative Trait Loci) were identified, and we highlighted the substantial influence of Roanoke, Lee and Bragg ancestor on the genetic makeup of Brazilian soybean varieties. Our findings demonstrate that certain markers are being lost in modern cultivars, while others maintain or even increase their frequency. These observations indicate genomic regions that have undergone selection during soybean introduction in Brazil and could be valuable in breeding programs aimed at enhancing protein or oil content.

Iron Content of Wheat and Rice in Australia: A Scoping Review.

With a shift towards plant-based diets for human and planetary health, monitoring the mineral content of staple crops is important to ensure population nutrient requirements can be met. This review aimed to explore changes in the iron content of unprocessed wheat and rice in Australia over time. A comprehensive systematic search of four electronic databases and the gray literature was conducted. A total of 25 papers published between 1930 and 2023 that measured the iron content of unprocessed wheat and rice were included. Triticum aestivum was the most common wheat type studied, including 26 cultivars; iron content ranged from 40 to 50 µg/g in the 1930s and 1970s and was more variable after this time due to the introduction of modern cultivars, with most values between 25 and 45 µg/g. The iron content of rice (Oryza sativa) was more consistent at 10-15 µg/g between the 1980s and 2020s. Variations over the years may be attributed to environmental, biological, and methodological factors but these were not well documented across all studies, limiting the interpretation of findings. As the number of individuals following plant-based diets continues to rise, the ongoing monitoring of the mineral content in commonly consumed plant-based foods is warranted.

Grain quality traits within the wheat (Triticum spp.) genepool: prospects for improved nutrition through de novo domestication.

Wild relatives of wheat (Triticum spp.) harbor beneficial alleles for potential improvement and de novo domestication of selected genotypes with advantageous traits. We analyzed the nutrient composition in wild diploid and tetraploid wheats and their domesticated diploid, tetraploid and hexaploid relatives under field conditions in Germany and compared them with modern Triticum aestivum and Triticum durum cultivars. Grain iron (Fe) and zinc (Zn) concentrations, phytate:mineral molar ratios, grain protein content (GPC) and antioxidant activity were analyzed across 125 genotypes. Grain Fe and Zn concentrations in wild wheats were 72 mg kg-1 and 59 mg kg-1, respectively, with improved bioavailability indicated by Phytate:Fe and Phytate:Zn molar ratios (11.7 and 16.9, respectively) and GPC (231 g kg-1). By comparison, grain Fe and Zn concentrations in landrace taxa were 54 mg kg-1 and 55 mg kg-1, respectively, with lower Phytate:Fe and Phytate:Zn molar ratios (15.1 and 17.5, respectively) and GPC (178 g kg-1). Average grain Fe accumulation in Triticum araraticum was 73 mg kg-1, reaching 116 mg kg-1, with high Fe bioavailability (Phyt:Fe: 11.7; minimum: 7.2). Wild wheats, landraces and modern cultivars showed no differences in antioxidant activity. Triticum zhukovskyi stood out with high grain micronutrient concentrations and favorable molar ratios. It was also the only taxon with elevated antioxidant activity. Our results indicate alteration of grain quality during domestication. T. araraticum has promising genotypes with advantageous grain quality characteristics that could be selected for de novo domestication. Favorable nutritional traits in the GGAA wheat lineage (T. araraticum and T. zhukovskyi) hold promise for improving grain quality traits. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Survey of Rice Genotypes of Southern India for Seed Zinc Concentration to Explore its Seed Endophytic Microbial Diversity

Background: Rice is a vital staple food for a large part of the global population and zinc deficiency poses health risks, particularly in rice-dependent regions. Studying genotypic differences in rice seed zinc content is vital for breeding zinc enriched varieties to address malnutrition and enhance food security. In the plant microbe partnership exploring the role of seed bacterial endophytes in influencing the plant physiology holds promise for Zn accumulation contributing to the broader goals of enhancing food quality, nutrition and crop production in a world facing increasing agricultural demands and challenges. Methods: Rice genotypes were surveyed and their seed zinc content was analysed using non-destructive X-ray fluorescence spectrometry. Surface sterilization of rice seed samples was performed to isolate endophytic bacteria, involving a series of treatments with distilled water, ethanol and sodium hypochlorite to remove surface microflora. The sterilized seeds were then macerated and diluted to obtain a countable number of colonies, which were subsequently spread-plated on nutrient agar, tryptic soy agar and soil extract agar to enumerate the different nutritional types of seed endophytic microflora. Result: In this study, 34 different rice genotypes, comprising traditional landraces and modern cultivars, were collected and analysed for their inherent zinc content. One variety in each category of low, medium and high seed Zn content was selected. The occurrence of all nutritional types of bacterial and their population was highest in the genotype Karuppunel followed by CO51 and ADT 39. Nutrient agar was found to promote a higher count of culturable bacterial endophytes compared to Tryptic soy agar and Soil extract agar.

Field phenotyping of ten wheat cultivars under elevated CO2 shows seasonal differences in chlorophyll fluorescence, plant height and vegetation indices.

In the context of climate change and global sustainable development goals, future wheat cultivation has to master various challenges at a time, including the rising atmospheric carbon dioxide concentration ([CO2]). To investigate growth and photosynthesis dynamics under the effects of ambient (~434 ppm) and elevated [CO2] (~622 ppm), a Free-Air CO2 Enrichment (FACE) facility was combined with an automated phenotyping platform and an array of sensors. Ten modern winter wheat cultivars (Triticum aestivum L.) were monitored over a vegetation period using a Light-induced Fluorescence Transient (LIFT) sensor, ground-based RGB cameras and a UAV equipped with an RGB and multispectral camera. The LIFT sensor enabled a fast quantification of the photosynthetic performance by measuring the operating efficiency of Photosystem II (Fq'/Fm') and the kinetics of electron transport, i.e. the reoxidation rates Fr1' and Fr2'. Our results suggest that elevated [CO2] significantly increased Fq'/Fm' and plant height during the vegetative growth phase. As the plants transitioned to the senescence phase, a pronounced decline in Fq'/Fm' was observed under elevated [CO2]. This was also reflected in the reoxidation rates Fr1' and Fr2'. A large majority of the cultivars showed a decrease in the harvest index, suggesting a different resource allocation and indicating a potential plateau in yield progression under e[CO2]. Our results indicate that the rise in atmospheric [CO2] has significant effects on the cultivation of winter wheat with strong manifestation during early and late growth.

Modulation of the nutritional and functional values of common bean by farming system: organic vs. conventional

Common bean (Phaseolus vulgaris L.) is a crop of high nutritional interest which is widespread throughout the world as a result of which it is considered as a potential crop for ensuring future food security. The effect of organic and conventional farming systems on the nutritional and functional composition of two cultivars of market class fabada (a landrace and a modern elite cultivar) is described. The findings of our study have shown that the common beans from organic farming have a higher content of protein, phenolic compounds, and relevant microelements such as iron and zinc than the seeds from conventional farming trial. However, in conventional crops a higher content of polyunsaturated fatty acids and lower concentrations of phytic acid and raffinose oligosaccharides were also detected. In contrast, no significant differences were detected in the proximate composition of the two genotypes tested, nor in their antioxidant activity or levels of phenolic compounds. The elite cultivar maintains the nutritional characteristics of the landrace from which it derives, suggesting the genomic regions modified in the improvement do not play an important role in their genetic control.

Early human selection of crops' wild progenitors explains the acquisitive physiology of modern cultivars.

Crops have resource-acquisitive leaf traits, which are usually attributed to the process of domestication. However, early choices of wild plants amenable for domestication may also have played a key role in the evolution of crops' physiological traits. Here we compiled data on 1,034 annual herbs to place the ecophysiological traits of 69 crops' wild progenitors in the context of global botanical variation, and we conducted a common-garden experiment to measure the effects of domestication on crop ecophysiology. Our study found that crops' wild progenitors already had high leaf nitrogen, photosynthesis, conductance and transpiration and soft leaves. After domestication, ecophysiological traits varied little and in idiosyncratic ways. Crops did not surpass the trait boundaries of wild species. Overall, the resource-acquisitive strategy of crops is largely due to the inheritance from their wild progenitors rather than to further breeding improvements. Our study concurs with recent literature highlighting constraints of crop breeding for faster ecophysiological traits.

Genetic diversity analysis of big-bracted dogwood (Cornus florida and C. kousa) cultivars, interspecific hybrids, and wild-collected accessions using RADseq.

Big-bracted dogwoods are popular ornamental trees known for their beautiful spring blooms with showy bracts and four-season appeal. The two most widely grown species are Cornus florida and Cornus kousa, native to Eastern North America and East Asia. Despite their horticultural prominence, there is little information available regarding genetic diversity, population structure, relatedness, and subspecies origins of dogwood cultivars. In this study, 313 cultivars, wild-collected plants, and Rutgers University breeding selections, focusing on C. florida, C. kousa, and interspecific hybrids, were genotyped using restriction-site associated DNA sequencing (RADseq) generating thousands of single nucleotide polymorphism (SNP) and insertion deletion (Indel) markers. The research results showed high genetic diversity among C. florida and C. kousa wild-collected plants and cultivars. For C. florida, pink-bracted plants formed a distinct clade from those with white-bracts with the Mexican C. florida ssp. urbiniana forming an outgroup. For C. kousa, Chinese-collected plants (ssp. chinensis) were a distinct subspecies with clear separation from Japanese and Korean accessions (ssp. kousa) and cultivars were designated as ssp. chinensis, ssp. kousa, or ssp. hybrid. Using this information, a Kompetitive allele specific PCR (KASP) assay genotyping panel was designed to determine C. kousa trees' subspecies makeup. Results revealed many cases of genetically identical cultivars being sold under different names, especially for pink-bracted cultivars of both species. Additionally, reported parent-progeny relationships were evaluated and either validated or discredited. Finally, the hybrid germplasm analysis validated pedigrees of interspecific F1 hybrids and found many of the recent Rutgers breeding selections contain small regions of pacific dogwood (C. nuttallii) DNA introgressed into C. kousa backgrounds. This diversity study elucidates origins, diversity, and relationships of a large population of big-bracted dogwoods. The results can inform plant breeders, arboreta, and the ornamental plant industry, as most modern cultivars and popular historic cultivars are represented.