Multi-trait association mapping for phosphorous efficiency reveals flexible root architectures in sorghum.

Background: On tropical regions, phosphorus (P) fixation onto aluminum and iron oxides in soil clays restricts P diffusion from the soil to the root surface, limiting crop yields. While increased root surface area favors P uptake under low-P availability, the relationship between the three-dimensional arrangement of the root system and P efficiency remains elusive. Here, we simultaneously assessed allelic effects of loci associated with a variety of root and P efficiency traits, in addition to grain yield under low-P availability, using multi-trait genome-wide association.

QTL mapping for bioenergy traits in sweet sorghum recombinant inbred lines.

During the past decade, sweet sorghum (Sorghum bicolor Moench L.) has shown great potential for bioenergy production, especially biofuels. In this study, 223 recombinant inbred lines (RILs) derived from a cross between two sweet sorghum lines (Brandes × Wray) were evaluated in three trials.

Sorgoleone concentration influences mycorrhizal colonization in sorghum.

The association between arbuscular mycorrhizal fungi (AMF) and sorghum, the fifth most cultivated cereal in the world and a staple food for many countries, is relevant to improving phosphorus (P) absorption. The importance of root exudation as a signal for the symbiosis has been shown for several species, but a complete understanding of the signaling molecules involved in the mycorrhizal symbiosis signaling pathway has not yet been elucidated. In this context, we investigated the effect of sorgoleone, one of the most studied allelochemicals and a predominant compound of root exudates in sorghum, on AMF colonization and consequently P uptake and plant growth on a sorghum genotype.

Association mapping and genomic selection for sorghum adaptation to tropical soils of Brazil in a sorghum multiparental random mating population.

A multiparental random mating population used in sorghum breeding is amenable for the detection of QTLs related to tropical soil adaptation, fine mapping of underlying genes and genomic selection approaches. Tropical soils where low phosphorus (P) and aluminum (Al) toxicity limit sorghum [Sorghum bicolor (L.) Moench] production are widespread in the developing world.

The genetic architecture of phosphorus efficiency in sorghum involves pleiotropic QTL for root morphology and grain yield under low phosphorus availability in the soil.

Background: Phosphorus (P) fixation on aluminum (Al) and iron (Fe) oxides in soil clays restricts P availability for crops cultivated on highly weathered tropical soils, which are common in developing countries. Hence, P deficiency becomes a major obstacle for global food security. We used multi-trait quantitative trait loci (QTL) mapping to study the genetic architecture of P efficiency and to explore the importance of root traits on sorghum grain yield on a tropical low-P soil.

Repeat variants for the SbMATE transporter protect sorghum roots from aluminum toxicity by transcriptional interplay in and .

Acidic soils, where aluminum (Al) toxicity is a major agricultural constraint, are globally widespread and are prevalent in developing countries. In sorghum, the root citrate transporter SbMATE confers Al tolerance by protecting root apices from toxic Al, but can exhibit reduced expression when introgressed into different lines. We show that allele-specific transactivation occurs and is caused by factors located away from Using expression-QTL mapping and expression genome-wide association mapping, we establish that transcription is controlled in a bipartite fashion, primarily in but also in Multiallelic promoter transactivation and ChIP analyses demonstrated that intermolecular effects on expression arise from a WRKY and a zinc finger-DHHC transcription factor (TF) that bind to and -activate the promoter.

Exploiting sorghum genetic diversity for enhanced aluminum tolerance: Allele mining based on the Alt locus.

Root damage due to aluminum (Al) toxicity restricts crop production on acidic soils, which are extensive in the tropics. The sorghum root Al-activated citrate transporter, SbMATE, underlies the Al tolerance locus, Alt, and increases grain yield under Al toxicity. Here, Alt loci associated with Al tolerance were converted into Amplification Refractory Mutation System (ARMS) markers, which are cost effective and easy to use.

Genomic prediction applied to high-biomass sorghum for bioenergy production.

The increasing cost of energy and finite oil and gas reserves have created a need to develop alternative fuels from renewable sources. Due to its abiotic stress tolerance and annual cultivation, high-biomass sorghum ( L. Moench) shows potential as a bioenergy crop.

Phenotypic and molecular characterization of sweet sorghum accessions for bioenergy production.

Sweet sorghum [Sorghum bicolor (L.) Moench] is a type of cultivated sorghum characterized by the accumulation of high levels of sugar in the stems and high biomass accumulation, making this crop an important feedstock for bioenergy production. Sweet sorghum breeding programs that focus on bioenergy have two main goals: to improve quantity and quality of sugars in the juicy stem and to increase fresh biomass productivity.

Mineral content of sorghum genotypes and the influence of water stress.

Sorghum is a source of several minerals whose content may vary depending on the genotype and the production environment. The objective of this study was to screen sorghum genotypes for mineral content and to investigate the effect of water stress on it. A large variability was observed in the mineral content of 100 sorghum genotypes grown in environments without (WoWS) and with water stress (WthWS).

Back to Acid Soil Fields: The Citrate Transporter SbMATE Is a Major Asset for Sustainable Grain Yield for Sorghum Cultivated on Acid Soils.

Aluminum (Al) toxicity damages plant roots and limits crop production on acid soils, which comprise up to 50% of the world's arable lands. A major Al tolerance locus on chromosome 3, AltSB, controls aluminum tolerance in sorghum [Sorghum bicolor (L.) Moench] via SbMATE, an Al-activated plasma membrane transporter that mediates Al exclusion from sensitive regions in the root apex.

Resistant starch content among several sorghum (Sorghum bicolor) genotypes and the effect of heat treatment on resistant starch retention in two genotypes.

The resistant starch (RS) contents in 49 sorghum genotypes and the effects of heat treatment using dry and wet heat on the grain and flour from two sorghum genotypes were investigated. The results showed a wide variation in the RS contents of the genotypes analyzed. The RS mean values were grouped into six distinct groups and ranged from 0.

Duplicate and conquer: multiple homologs of PHOSPHORUS-STARVATION TOLERANCE1 enhance phosphorus acquisition and sorghum performance on low-phosphorus soils.

Low soil phosphorus (P) availability is a major constraint for crop production in tropical regions. The rice (Oryza sativa) protein kinase, PHOSPHORUS-STARVATION TOLERANCE1 (OsPSTOL1), was previously shown to enhance P acquisition and grain yield in rice under P deficiency. We investigated the role of homologs of OsPSTOL1 in sorghum (Sorghum bicolor) performance under low P.

Association mapping provides insights into the origin and the fine structure of the sorghum aluminum tolerance locus, AltSB.

Root damage caused by aluminum (Al) toxicity is a major cause of grain yield reduction on acid soils, which are prevalent in tropical and subtropical regions of the world where food security is most tenuous. In sorghum, Al tolerance is conferred by SbMATE, an Al-activated root citrate efflux transporter that underlies the major Al tolerance locus, AltSB, on sorghum chromosome 3. We used association mapping to gain insights into the origin and evolution of Al tolerance in sorghum and to detect functional variants amenable to allele mining applications.

Incomplete transfer of accessory loci influencing SbMATE expression underlies genetic background effects for aluminum tolerance in sorghum.

Impaired root development caused by aluminum (Al) toxicity is a major cause of grain yield reduction in crops cultivated on acid soils, which are widespread worldwide. In sorghum, the major Al-tolerance locus, AltSB , is due to the function of SbMATE, which is an Al-activated root citrate transporter. Here we performed a molecular and physiological characterization of various AltSB donors and near-isogenic lines harboring various AltSB alleles.

The relationship between population structure and aluminum tolerance in cultivated sorghum.

Background: Acid soils comprise up to 50% of the world's arable lands and in these areas aluminum (Al) toxicity impairs root growth, strongly limiting crop yield. Food security is thereby compromised in many developing countries located in tropical and subtropical regions worldwide. In sorghum, SbMATE, an Al-activated citrate transporter, underlies the Alt(SB) locus on chromosome 3 and confers Al tolerance via Al-activated root citrate release.

Comparative mapping of a major aluminum tolerance gene in sorghum and other species in the poaceae.

In several crop species within the Triticeae tribe of the grass family Poaceae, single major aluminum (Al) tolerance genes have been identified that effectively mitigate Al toxicity, a major abiotic constraint to crop production on acidic soils. However, the trait is quantitatively inherited in species within other tribes, and the possible ancestral relationships between major Al tolerance genes and QTL in the grasses remain unresolved. To help establish these relationships, we conducted a molecular genetic analysis of Al tolerance in sorghum and integrated our findings with those from previous studies performed in crop species belonging to different grass tribes.

Growth and Nutrition of Mollicute-Infected Maize.

Maize bushy stunt phytoplasma (MBSP) and corn stunt spiroplasma (CSS) diseases are widespread in Brazil. The leafhopper Dalbulus maidis is the insect vector for these pathogenic mollicutes. The effects of these diseases on the development of maize plants and the possible interaction of soil water availability on these effects were evaluated in two experiments carried out on potted plants.