Key message
Rfo is located on a radish chromosome fragment (~ 108 Kb), which is seated in the middle of a pretty large C genome translocation at the distal region of chromosome A09 of B. juncea.
...Ogura cytoplasmic male sterility (CMS) is used to produce hybrids in Indian mustard (
Brassica juncea
L.). Fertility restorers for this CMS were developed by cross-hybridizing
B. juncea
(AABB; 2
n
= 36) with
B. napus
(AACC; 2
n
= 38) carrying radish
Rfo
gene. This hybrid production system is normally stable, but many commercial mustard hybrids show male sterile contaminants. We aimed to identify linkage drag associated with
Rfo
by comparing hybridity levels of 295 handmade CMS x
Rfo
crosses. Although
Rfo
was stably inherited, hybridity was < 85 percent in several combinations. Genome re-sequencing of five fertility restorers, mapping sequencing reads to
B. juncea
reference and synteny analysis with
Raphanus sativus
D81
Rfo
genomic region (AJ550021.2) helped to detect ~ 108 Kb of radish chromosome (R) fragment substitution in all fertility restorers. This radish segment substitution was itself located amidst a large C genome translocation on the terminal region of chromosome A09 of
B. juncea
. The size of alien segment substitution varied from 11.3 (NTCN-R9) to 22.0 Mb (NAJR-102B-R). We also developed an in silico SSR map for chromosome A09 and identified many homoeologous A to the C genome exchanges in the introgressed region. A to the R genome exchanges were rare. Annotation of the substituted fragment showed the gain of many novel genes from R and C genomes and the loss of
B. juncea
genes from the corresponding region. We have developed a KASPar marker for marker-aided transfer of
Rfo
and testing hybridity levels in seed production lots.
Feeding 10 billion people sustainably by 2050 in the era of slow genetic progress has spurred urgent calls to bring more crops per unit time. Over the last century, crop physiologists and breeders ...have been trying to alter plant biology to investigate and intervene in developmental processes under controlled chambers. Accelerating the breeding cycle via “speed breeding” was the outcome of these experiments. Speed breeding accelerates the genetic gain via phenome and genome-assisted trait introgression, re-domestication, and plant variety registration. Furthermore, early varietal release through speed breeding offers incremental benefits over conventional methods. However, a lack of resources and species-specific protocols encumber the technological implementation, which can be alleviated by reallocating funds to establish speed breeding units. This review discusses the limitations of conventional breeding methods and various alternative strategies to accelerate the breeding process. It also discusses the intervention at various developmental stages to reduce the generation time and global impacts of speed breeding protocols developed so far. Low-cost, field-based speed breeding protocol developed by Punjab Agricultural University, Ludhiana, Punjab, India to harvest at least three generations of wheat in a year without demanding the expensive greenhouses or growth chambers is also discussed.
Wheat is an important cereal crop constrained by several biotic and abiotic stresses including drought stress. Understating the effect of drought stress and the genetic basis of stress tolerance is ...important to develop drought resilient, high-yielding wheat cultivars. In this study, we investigated the effects of drought stress on seedling characteristics in an association panel consisting of 198 germplasm lines. Our findings revealed that drought stress had a detrimental effect on all the seedling characteristics under investigation with a maximum effect on shoot length (50.94% reduction) and the minimum effect on germination percentage (7.9% reduction). To gain a deeper understanding, we conducted a genome-wide association analysis using 12,511 single nucleotide polymorphisms (SNPs), which led to the identification of 39 marker-trait associations (MTAs). Of these 39 MTAs, 13 were particularly noteworthy as they accounted for >10% of the phenotypic variance with a LOD score >5. These high-confidence MTAs were further utilized to extract 216 candidate gene (CGs) models within 1 Mb regions. Gene annotation and functional characterization identified 83 CGs with functional relevance to drought stress. These genes encoded the WD40 repeat domain, Myb/SANT-like domain, WSD1-like domain, BTB/POZ domain, Protein kinase domain, Cytochrome P450, Leucine-rich repeat domain superfamily, BURP domain, Calmodulin-binding protein60, Ubiquitin-like domain, etc. Findings from this study hold significant promise for wheat breeders as they provide direct assistance in selecting lines harboring favorable alleles for improved drought stress tolerance. Additionally, the identified SNPs and CGs will enable marker-assisted selection of potential genomic regions associated with enhanced drought stress tolerance in wheat.
Grain protein content (GPC) is an important quality trait that effectively modulates end-use quality and nutritional characteristics of wheat flour-based food products. The
gene is responsible for ...the higher protein content in wheat grain. In addition to higher GPC, the
is also generally associated with reduced grain filling period which eventually causes the yield penalty in wheat. The main aim of the present study was to evaluate the effect of foliar application of potassium nitrate (PN) and salicylic acid (SA) on the physiological characteristics of a set of twelve genotypes, including nine isogenic wheat lines carrying the
gene and three elite wheat varieties with no
gene, grown at wheat experimental area of the Department of Plant Breeding and Genetics, PAU, Punjab, India. The PN application significantly increased the number of grains per spike (GPS) by 6.42 grains, number of days to maturity (DTM) by 1.03 days, 1000-grain weight (TGW) by 1.97 g and yield per plot (YPP) by 0.2 kg/plot. As a result of PN spray, the flag leaf chlorophyll content was significantly enhanced by 2.35 CCI at anthesis stage and by 1.96 CCI at 10 days after anthesis in all the tested genotypes. Furthermore, the PN application also significantly increased the flag leaf nitrogen content by an average of 0.52% at booting stage and by 0.35% at both anthesis and 10 days after anthesis in all the evaluated genotypes. In addition, the yellow peduncle colour at 30 days after anthesis was also increased by 19.08% while the straw nitrogen content was improved by 0.17% in all the genotypes. The preliminary experiment conducted using SA demonstrated a significant increase in DTM and other yield component traits. The DTM increased by an average of 2.31 days, GPS enhanced by approximately 3.17 grains, TGW improved by 1.13g, and YPP increased by 0.21 kg/plot. The foliar application of PN and SA had no significant effect on GPC itself. The findings of the present study suggests that applications of PN and SA can effectively mitigate the yield penalty associated with
gene by extending grain filling period in the wheat.
The fluctuating climates, rising human population, and deteriorating arable lands necessitate sustainable crops to fulfil global food requirements. In the countryside, legumes with intriguing but ...enigmatic nitrogen-fixing abilities and thriving in harsh climatic conditions promise future food security. However, breaking the yield plateau and achieving higher genetic gain are the unsolved problems of legume improvement. Present study gives emphasis on 15 important legume crops, i.e., chickpea, pigeonpea, soybean, groundnut, lentil, common bean, faba bean, cowpea, lupin, pea, green gram, back gram, horse gram, moth bean, rice bean, and some forage legumes. We have given an overview of the world and India’s area, production, and productivity trends for all legume crops from 1961 to 2020. Our review article investigates the importance of gene pools and wild relatives in broadening the genetic base of legumes through pre-breeding and alien gene introgression. We have also discussed the importance of integrating genomics, phenomics, speed breeding, genetic engineering and genome editing tools in legume improvement programmes. Overall, legume breeding may undergo a paradigm shift once genomics and conventional breeding are integrated in the near future.
Aegilops tauchii is a D-genome donor of hexaploid wheat and is a potential source of genes for various biotic and abiotic stresses including heat and drought. In the present study, we used ...multi-stage evaluation technique to understand the effects of heat and drought stresses on Ae. tauschii derived introgression lines (ILs). Preliminary evaluation (during stage-I) of 369 ILs for various agronomic traits identified 59 agronomically superior ILs. In the second stage (stage-II), selected ILs ( i.e. , 59 ILs) were evaluated for seedling heat (at 30 °C and 35 °C) and drought (at 20% poly-ethylene glycol; PEG) stress tolerance under growth chambers (stage-II). Heat and drought stress significantly reduced the seedling vigour by 59.29 and 60.37 percent, respectively. Genotype × treatment interaction analysis for seedling vigour stress tolerance index (STI) identified IL-50, IL-56, and IL-68 as high-performing ILs under heat stress and IL-42 and IL-44 as high-performing ILs under drought stress. It also revealed IL-44 and IL-50 as the stable ILs under heat and drought stresses. Furthermore, in the third stage (stage-III), selected ILs were evaluated for heat and drought stress tolerance under field condition over two cropping seasons (viz., 2020–21 and 2021–22), which significantly reduced the grain yield by 72.79 and 48.70 percent, respectively. Stability analysis was performed to identify IL-47, IL-51, and IL-259 as the most stable ILs in stage-III. Tolerant ILs with specific and wider adaptability identified in this study can serve as the potential resources to understand the genetic basis of heat and drought stress tolerance in wheat and they can also be utilized in developing high-yielding wheat cultivars with enhanced heat and drought stress tolerance.
A meta-analysis of quantitative trait loci (QTLs), associated with agronomic traits, fertility restoration, disease resistance, and seed quality traits was conducted for the first time in pigeonpea ...(Cajanus cajan L.). Data on 498 QTLs was collected from 9 linkage mapping studies (involving 21 biparental populations). Of these 498, 203 QTLs were projected onto "PigeonPea_ConsensusMap_2022," saturated with 10,522 markers, which resulted in the prediction of 34 meta-QTLs (MQTLs). The average confidence interval (CI) of these MQTLs (2.54 cM) was 3.37 times lower than the CI of the initial QTLs (8.56 cM). Of the 34 MQTLs, 12 high-confidence MQTLs with CI (≤5 cM) and a greater number of initial QTLs (≥5) were utilized to extract 2255 gene models, of which 105 were believed to be associated with different traits under study. Furthermore, eight of these MQTLs were observed to overlap with several marker-trait associations or significant SNPs identified in previous genome-wide association studies. Furthermore, synteny and ortho-MQTL analyses among pigeonpea and four related legumes crops, such as chickpea, pea, cowpea, and French bean, led to the identification of 117 orthologous genes from 20 MQTL regions. Markers associated with MQTLs can be employed for MQTL-assisted breeding as well as to improve the prediction accuracy of genomic selection in pigeonpea. Additionally, MQTLs may be subjected to fine mapping, and some of the promising candidate genes may serve as potential targets for positional cloning and functional analysis to elucidate the molecular mechanisms underlying the target traits.
Iron (Fe) deficiency is a pressing global health concern, particularly affecting vulnerable groups like women and children in resource-limited areas. Addressing this challenge requires innovative ...solutions, and biofortified crops, like Fe-enriched wheat, can offer a sustainable solution to improve nutrition in cereal-based diets. While conventional breeding methods have yielded competitive Fe-biofortified wheat varieties across various nations, the imminent challenges in securing food and nutritional security for the future necessitate a delicate balance: maintaining genetic progress in grain yield while concurrently elevating grain Fe content. Despite substantial strides in elucidating the intricacies of Fe homeostasis, there remains a substantial knowledge gap, especially in the context of wheat and similar crop species. It is paramount to gain a comprehensive understanding of the hurdles impeding Fe enrichment in plant tissues and delve into the diverse mechanisms governing Fe uptake, translocation, transport, and storage within wheat. To surmount these challenges, researchers have explored a multitude of strategies, including mutagenesis, QTL mapping, meta-QTL analysis, GWAS, transgenesis, and genome editing. Furthermore, harnessing the potential of microorganisms, particularly engineered endophytes coupled with plant genes associated with Fe accumulation, emerges as a promising and pragmatic tool for augmenting Fe biofortification in wheat. This comprehensive review underscores the significant advancements made in unravelling the genetic and genomic aspects of Fe accumulation in wheat, while also delineating the future research directions in this field. By synergistically deploying these multifaceted approaches, scientists hold the potential to develop wheat varieties characterized by enhanced grain Fe content, improved bioavailability, and reduced anti-nutritional factors. Such innovations can play a pivotal role in advancing nutrition and health outcomes for populations reliant on wheat-based diets, particularly in resource-scarce regions.
•Iron deficiency is a major global health concern. To address it, we can increase Fe content in staple crops like wheat.•Different conventional and modern breeding approaches can be employed for Fe biofortification of wheat grains.•A key challenge is to increase the Fe content in wheat grains while preserving genetic gains for grain yield.•Integration of plant genes with microbes, particularly engineered endophytes can improve Fe homeostasis in wheat plants.
Abstract The need to cover the exposed periostium has meant that a number of materials including mucosal and skin grafts are regarded as suitable for grafting in oral and maxillofacial surgery. To ...circumvent the disadvantages of other materials such as skin, biological membranes have been suggested as options, including fetal membrane. The objective of the present study was to evaluate the clinical efficacy of amnion as a graft material for vestibuloplasty, to increase the depth of the sulcus for complete rehabilitation with dentures in 10 patients with a follow up period of 3 months. Ten patients with deficient depth of the mandibular vestibular sulcus who were referred from the Department of Prosthodontics were listed for mandibular labial vestibuloplasty using Clark's technique followed by grafting with amnion over the denuded periostium. The vestibular depth was evaluated at the end of the 1st week, 2nd week, 4th week, and 3rd month postoperatively, and compared with the preoperative vestibular depth. We had no cases of graft necrosis either complete or partial. However, the reduction in the depth of the labial vestibule ranged from 17% to 50% after 3 months’ follow up. A mean (SD) labial vestibular depth of 13.3 (1.8) mm was achieved immediately postoperatively, and 10.0 (3.1) mm at 3 months’ follow up. We conclude that grafts of amniotic membrane are viable and reliable for covering of the raw surface, prevent secondary contraction after vestibuloplasty, and maintain the postoperative vestibular depth.
Main conclusion
Meta-analysis in wheat for three major quality traits identified 110 meta-QTL (MQTL) with reduced confidence interval (CI). Five GWAS validated MQTL (viz., 1A.1, 1B.2, 3B.4, 5B.2, and ...6B.2), each involving more than 20 initial QTL and reduced CI (95%) (< 2 cM), were selected for quality breeding programmes. Functional characterization including candidate gene mining and expression analysis discovered 44 high confidence candidate genes associated with quality traits.
A meta-analysis of quantitative trait loci (QTL) associated with dough rheology properties, nutritional traits, and processing quality traits was conducted in wheat. For this purpose, as many as 2458 QTL were collected from 50 interval mapping studies published during 2013–2020. Of the total QTL, 1126 QTL were projected onto the consensus map saturated with 249,603 markers which led to the identification of 110 meta-QTL (MQTL). These MQTL exhibited an 18.84-fold reduction in the average CI compared to the average CI of the initial QTL (ranging from 14.87 to 95.55 cM with an average of 40.35 cM). Of the 110, 108 MQTL were physically anchored to the wheat reference genome, including 51 MQTL verified with marker-trait associations (MTAs) reported from earlier genome-wide association studies. Candidate gene (CG) mining allowed the identification of 2533 unique gene models from the MQTL regions. In-silico expression analysis discovered 439 differentially expressed gene models with > 2 transcripts per million expressions in grains and related tissues, which also included 44 high-confidence CGs involved in the various cellular and biochemical processes related to quality traits. Nine functionally characterized wheat genes associated with grain protein content, high-molecular-weight glutenin, and starch synthase enzymes were also found to be co-localized with some of the MQTL. Synteny analysis between wheat and rice MQTL regions identified 23 wheat MQTL syntenic to 16 rice MQTL associated with quality traits. Furthermore, 64 wheat orthologues of 30 known rice genes were detected in 44 MQTL regions. Markers flanking the MQTL identified in the present study can be used for marker-assisted breeding and as fixed effects in the genomic selection models for improving the prediction accuracy during quality breeding. Wheat orthologues of rice genes and other CGs available from MQTLs can be promising targets for further functional validation and to better understand the molecular mechanism underlying the quality traits in wheat.
