Mucilage secretion by aerial roots in sorghum (Sorghum bicolor): sugar profile, genetic diversity, GWAS and transcriptomic analysis.

Aerial root mucilage can enhance nitrogen fixation by providing sugar and low oxygen environment to the rhizosphere microbiome in Sierra Mixe maize. Aerial root mucilage has long been documented in sorghum (Sorghum bicolor), but little is known about the biological significance, genotypic variation, and genetic regulation of this biological process. In the present study, we found that a large variation of mucilage secretion capacity existed in a sorghum panel consisting of 146 accessions.

The Arabidopsis thaliana onset of leaf death 12 mutation in the lectin receptor kinase P2K2 results in an autoimmune phenotype.

Background: Plant immunity relies on the perception of immunogenic signals by cell-surface and intracellular receptors and subsequent activation of defense responses like programmed cell death. Under certain circumstances, the fine-tuned innate immune system of plants results in the activation of autoimmune responses that cause constitutive defense responses and spontaneous cell death in the absence of pathogens.

Results: Here, we characterized the onset of leaf death 12 (old12) mutant that was identified in the Arabidopsis accession Landsberg erecta.

Genomic architecture of leaf senescence in sorghum (Sorghum bicolor).

Leaf senescence in sorghum is primarily controlled by the progression, but not by the onset of senescence. The senescence-delaying haplotypes of 45 key genes accentuated from landraces to improved lines. Leaf senescence is a genetically programmed developmental process and plays a central role for plant survival and crop production by remobilising nutrients accumulated in senescent leaves.

A mutation in Arabidopsis SAL1 alters its in vitro activity against IP and delays developmental leaf senescence in association with lower ROS levels.

Our manuscript is the first to find a link between activity of SAL1/OLD101 against IP and plant leaf senescence regulation and ROS levels assigning a potential biological role for IP. Leaf senescence is a genetically programmed process that limits the longevity of a leaf. We identified and analyzed the recessive Arabidopsis stay-green mutation onset of leaf death 101 (old101).

Genomic footprints of sorghum domestication and breeding selection for multiple end uses.

Domestication and diversification have had profound effects on crop genomes. Originating in Africa and subsequently spreading to different continents, sorghum (Sorghum bicolor) has experienced multiple onsets of domestication and intensive breeding selection for various end uses. However, how these processes have shaped sorghum genomes is not fully understood.

SorGSD: updating and expanding the sorghum genome science database with new contents and tools.

Background: As the fifth major cereal crop originated from Africa, sorghum (Sorghum bicolor) has become a key C model organism for energy plant research. With the development of high-throughput detection technologies for various omics data, much multi-dimensional and multi-omics information has been accumulated for sorghum. Integrating this information may accelerate genetic research and improve molecular breeding for sorghum agronomic traits.

Combined QTL mapping and association study reveals candidate genes for leaf number and flowering time in maize.

Twelve QTL for flowering and leaf number were detected. The ZmWRKY14 could increase leaf number, flowering time and biomass yield which are promising for silage maize breeding. Silage maize, one of the most important feedstock for ruminants, is widely grown from temperate regions to the tropics.

Potential interaction between autophagy and auxin during maize leaf senescence.

Leaf senescence is important for crop yield as delaying it can increase the average yield. In this study, population genetics and transcriptomic profiling were combined to dissect its genetic basis in maize. To do this, the progenies of an elite maize hybrid Jidan27 and its parental lines Si-287 (early senescence) and Si-144 (stay-green), as well as 173 maize inbred lines were used.

Sorghum breeding in the genomic era: opportunities and challenges.

The importance and potential of the multi-purpose crop sorghum in global food security have not yet been fully exploited, and the integration of the state-of-art genomics and high-throughput technologies into breeding practice is required. Sorghum, a historically vital staple food source and currently the fifth most important major cereal, is emerging as a crop with diverse end-uses as food, feed, fuel and forage and a model for functional genetics and genomics of tropical grasses. Rapid development in high-throughput experimental and data processing technologies has significantly speeded up sorghum genomic researches in the past few years.

Stem vacuole-targetted sucrose isomerase enhances sugar content in sorghum.

Background: Sugar content is critically important in determining sugar crop productivity. However, improvement in sugar content has been stagnant among sugar crops for decades. Sorghum, especially sweet sorghum with high biomass, shown great potential for biofuel, has lower sugar content than sugarcane.

Genome-wide association study reveals that different pathways contribute to grain quality variation in sorghum (Sorghum bicolor).

Background: In sorghum (Sorghum bicolor), one paramount breeding objective is to increase grain quality. The nutritional quality and end use value of sorghum grains are primarily influenced by the proportions of tannins, starch and proteins, but the genetic basis of these grain quality traits remains largely unknown. This study aimed to dissect the natural variation of sorghum grain quality traits and identify the underpinning genetic loci by genome-wide association study.

Sweet Sorghum Originated through Selection of , a Plant-Specific NAC Transcription Factor Gene.

Sorghum () is the fifth most popular crop worldwide and a C model plant. Domesticated sorghum comes in many forms, including sweet cultivars with juicy stems and grain sorghum with dry, pithy stems at maturity. The locus, which controls the pithy/juicy stem trait, was discovered over a century ago.

Phenotypic Analysis and Molecular Markers of Leaf Senescence.

The process of leaf senescence consists of the final stage of leaf development. It has evolved as a mechanism to degrade macromolecules and micronutrients and remobilize them to other developing parts of the plant; hence it plays a central role for the survival of plants and crop production. During senescence, a range of physiological, morphological, cellular, and molecular events occur, which are generally referred to as the senescence syndrome that includes several hallmarks such as visible yellowing, loss of chlorophyll and water content, increase of ion leakage and cell death, deformation of chloroplast and cell structure, as well as the upregulation of thousands of so-called senescence-associated genes (SAGs) and downregulation of photosynthesis-associated genes (PAGs).

Transcriptome profiling of developmental leaf senescence in sorghum (Sorghum bicolor).

This piece of the submission is being sent via mail. Leaf senescence is essential for the nutrient economy of crops and is executed by so-called senescence-associated genes (SAGs). Here we explored the monocot C model crop Sorghum bicolor for a holistic picture of SAG profiles by RNA-seq.

Erratum to: SorGSD: a sorghum genome SNP database.

[This corrects the article DOI: 10.1186/s13068-015-0415-8.].

SorGSD: a sorghum genome SNP database.

Background: Sorghum (Sorghum bicolor) is one of the most important cereal crops globally and a potential energy plant for biofuel production. In order to explore genetic gain for a range of important quantitative traits, such as drought and heat tolerance, grain yield, stem sugar accumulation, and biomass production, via the use of molecular breeding and genomic selection strategies, knowledge of the available genetic variation and the underlying sequence polymorphisms, is required.

Results: Based on the assembled and annotated genome sequences of Sorghum bicolor (v2.

Living to Die and Dying to Live: The Survival Strategy behind Leaf Senescence.

Senescence represents the final developmental act of the leaf, during which the leaf cell is dismantled in a coordinated manner to remobilize nutrients and to secure reproductive success. The process of senescence provides the plant with phenotypic plasticity to help it adapt to adverse environmental conditions. Here, we provide a comprehensive overview of the factors and mechanisms that control the onset of senescence.

TANG1, Encoding a Symplekin_C Domain-Contained Protein, Influences Sugar Responses in Arabidopsis.

Sugars not only serve as energy and cellular carbon skeleton but also function as signaling molecules regulating growth and development in plants. Understanding the molecular mechanisms in sugar signaling pathways will provide more information for improving plant growth and development. Here, we describe a sugar-hypersensitive recessive mutant, tang1.

Stability and genetic control of morphological, biomass and biofuel traits under temperate maritime and continental conditions in sweet sorghum (Sorghum bicolour).

Eight morphological, biomass and biofuel traits were found with high broad-sense heritability and 18 significant QTLs discovered including one locus controlling the stem juice trait for sorghum grown in Denmark and China. Sweet sorghum with tall plant, fast maturation and high stem Brix content can be bred as a biofuel crop for Northern Europe. Sweet sorghum (Sorghum bicolour), a native tropical C4 crop, has attracted interest as a bioenergy crop in northern countries due to its juice-rich stem and high biomass production.

PAV markers in Sorghum bicolour: genome pattern, affected genes and pathways, and genetic linkage map construction.

5,511 genic small-size PAVs in sorghum were identified and examined, including the pattern and the function enrichment of PAV genes. 325 PAV markers were developed to construct a genetic map. Presence/absence variants (PAVs) correlate closely to the phenotypic variation, by impacting plant genome sizes and the adaption to the environment.

Sugar-rich sweet sorghum is distinctively affected by wall polymer features for biomass digestibility and ethanol fermentation in bagasse.

Sweet sorghum has been regarded as a typical species for rich soluble-sugar and high lignocellulose residues, but their effects on biomass digestibility remain unclear. In this study, we examined total 63 representative sweet sorghum accessions that displayed a varied sugar level at stalk and diverse cell wall composition at bagasse. Correlative analysis showed that both soluble-sugar and dry-bagasse could not significantly affect lignocellulose saccharification under chemical pretreatments.

Genome-wide patterns of large-size presence/absence variants in sorghum.

The presence/absence variants (PAVs) are a major source of genome structural variation and have profound effects on phenotypic and genomic variation in animals and humans. However, little is understood about PAVs in plant genomes. Our previous resequencing effort on three sorghum (Sorghum bicolour L.

SbHKT1;4, a member of the high-affinity potassium transporter gene family from Sorghum bicolor, functions to maintain optimal Na⁺ /K⁺ balance under Na⁺ stress.

In halophytic plants, the high-affinity potassium transporter HKT gene family can selectively uptake K⁺ in the presence of toxic concentrations of Na⁺. This has so far not been well examined in glycophytic crops. Here, we report the characterization of SbHKT1;4, a member of the HKT gene family from Sorghum bicolor.