Genetic Improvement of Cereal Crops for Resistance to Biotic and Abiotic Stresses

A special issue of Plants (ISSN 2223-7747). This special issue belongs to the section "Plant Genetics, Genomics and Biotechnology".

Deadline for manuscript submissions: closed (28 February 2022) | Viewed by 47812

Special Issue Editors


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Guest Editor
Research Centre for Cereal and Industrial Crops, CREA, SS 673, Km 25.200, 71122 Foggia, Italy
Interests: new breeding technologies; abiotic stress; functional foods
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Research Centre for Cereal and Industrial Crops, Council for Agricultural Research and Economics, 71122 Foggia, Italy
Interests: durum wheat; disease resistance; genetic mapping; quantitative traits; cisgenesis
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Cereal crops are the major source of raw food material and nutritional components for human consumption and for feed for livestock around the world. Biotic and abiotic stresses are the leading cause of yield loss, decreasing crop productivity by 50%–80% depending on the crop and geographical location. Biotic stresses include insect pests, fungi, bacteria, and viruses. Among abiotic stresses, cold, drought, and salinity are the most studied in cereals. Stress-resistant crops are needed to ensure yield stability under stress conditions and to minimize the environmental impacts of crop production, exacerbated by climate change and application of improper agricultural practices. In the past, most breeding efforts aimed for high crop yields but beneficial alleles that contribute to stress resistance are often lost during conventional breeding because they do not contribute directly to yield. Modern breeding programs aiming at increasing stress resistance returned to traditional landraces and/or wild relatives of the major crops for restoring favorable stress resistance alleles. One difficulty in the breeding of stress resistant cultivars is the complex genetic architecture of stress responses, which is controlled by many quantitative trait loci with a small effect and their complex interactions, and of the variations in the duration, severity, and/or combinations of stresses. Hundreds of genes and QTLs involved in plant stress responses have been identified in cereal crops. Genome sequences are now available for many crops, useful for identifying novel genes or haplotypes responsible for these traits. To provide an overview of genetic improvements to stress responses and how this knowledge can be used in agriculture in modern plant breeding programs, we invite contributions for a Special Issue entitled Genetic Improvement of Cereal Crops for Resistance to Biotic and Abiotic Stresses.

Dr. Grazia Maria Borrelli
Dr. Daniela Marone
Guest Editors

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Keywords

  • Cereal crops
  • biotic and abiotic stress
  • genetic resources
  • marker-assisted selection
  • linkage and association mapping
  • haplotype analysis
  • NBT approaches

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Published Papers (11 papers)

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Research

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20 pages, 2037 KiB  
Article
Combining Ability and Performance of Extra-Early Maturing Provitamin A Maize Inbreds and Derived Hybrids in Multiple Environments
by Olatise Oluwaseun, Baffour Badu-Apraku, Moses Adebayo and Adamu Masari Abubakar
Plants 2022, 11(7), 964; https://doi.org/10.3390/plants11070964 - 1 Apr 2022
Cited by 5 | Viewed by 2454
Abstract
Availability of maize (Zea mays L.) hybrids with elevated provitamin A (PVA) levels and tolerance to contrasting stresses would improve food self-sufficiency and combat malnutrition in sub-Saharan Africa (SSA). This study was conducted to (i) analyze selected PVA inbreds of extra-early maturity [...] Read more.
Availability of maize (Zea mays L.) hybrids with elevated provitamin A (PVA) levels and tolerance to contrasting stresses would improve food self-sufficiency and combat malnutrition in sub-Saharan Africa (SSA). This study was conducted to (i) analyze selected PVA inbreds of extra-early maturity for carotenoid content, (ii) estimate the combining abilities of the inbred lines for grain yield and other agronomic traits, (iii) assign inbred lines to distinct heterotic groups (HGs), (iv) identify testers among the inbred lines, and (v) determine grain yield and stability of the PVA hybrids across contrasting environments. Thirty-three extra-early maturing inbred lines selected for high carotenoid content were crossed with four inbred testers to obtain 132 testcrosses. The testcrosses, six tester × tester crosses and two hybrid checks, were evaluated across three Striga-infested, four drought and five optimal growing environments in Nigeria, 2014–2016. Results of the chemical analysis revealed that inbred lines TZEEIOR 109, TZEEIOR 30, TZEEIOR 41, TZEEIOR 97, TZEEIOR 42, and TZEEIOR 140 had intermediate PVA levels. Both additive and nonadditive gene actions were important in the inheritance of grain yield and other measured traits under stress and optimal environments. However, additive gene action was preponderant over the nonadditive gene action. The inbred lines were classified into three HGs across environments. Inbreds TZEEIOR 249 and TZEEIOR 30 were identified as testers for HGs I and II, respectively. The hybrid TZEEI 79 × TZEEIOR 30 was the most outstanding in terms of grain yield and was stable across environments. This hybrid should be tested extensively in on-farm trials for consistency in performance and commercialized to combat malnutrition and food insecurity in SSA. Full article
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15 pages, 3805 KiB  
Article
Genotype and Phenotype Interaction between OsWKRYq6 and BLB after Xanthomonas oryzae pv. Oryzae Inoculation in the Field
by Xiao-Xuan Du, Jae-Ryoung Park, Xiao-Han Wang, Rahmatullah Jan, Gang-Seob Lee and Kyung-Min Kim
Plants 2022, 11(3), 287; https://doi.org/10.3390/plants11030287 - 21 Jan 2022
Cited by 4 | Viewed by 5350
Abstract
Bacterial leaf blight (BLB) is an important and devastating rice disease caused by the pathogen Xanthomonas oryzae pv. Oryzae (Xoo). In particular, in recent years, the occurrence of abnormal climate and warming phenomena has produced a good environment for the occurrence [...] Read more.
Bacterial leaf blight (BLB) is an important and devastating rice disease caused by the pathogen Xanthomonas oryzae pv. Oryzae (Xoo). In particular, in recent years, the occurrence of abnormal climate and warming phenomena has produced a good environment for the occurrence of BLB, and the rice yield due to the occurrence of BLB continues to decrease. Currently, molecular breeding is applied by searching for resistant genes to development of BLB resistance cultivar. In addition, there are many methods for screening resistant genes, and among them, phenotype analysis in the field and applied research is rarely conducted. Due to recent rapid climate change, BLB is a major problem that has a more serious negative effect on rice yield. Therefore, we suggest OsWRKYq6 to be effectively used for breeding BLB-resistant cultivars by screening BLB-resistant genes. In this study, the BLB-resistant gene was screened using the lesion length, which most definitely changes to the phenotype when Xoo is infected. OsWRKYq6 was finally selected as a BLB resistance gene by analyzing the phenotype and genotype after inoculating Xoo in 120 Cheongcheong/Nagdong double haploid (CNDH) lines in the field. After Xoo inoculation, lesion length and yield were investigated, and 120 CNDH lines were divided from BLB-resistant and susceptible lines. Moreover, when the transcription level of OsWRKYq6 was analyzed in the resistant and susceptible lines after Xoo inoculation in the field, the expression level was regulated to a high level in the resistant line. In this study, we propose OsWRKYq6 as a transcription factor involved in BLB resistance. Currently, the differentiation of various races is proceeding rapidly due to rapid climate change. In addition, screening of transcription factor genes involved in BLB resistance in the field can be effectively applied to molecular breeding to develop resistant cultivars in preparation for rapid climate change. Full article
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12 pages, 12594 KiB  
Article
New Genotypes and Genomic Regions for Resistance to Wheat Blast in South Asian Germplasm
by Chandan Roy, Philomin Juliana, Muhammad R. Kabir, Krishna K. Roy, Navin C. Gahtyari, Felix Marza, Xinyao He, Gyanendra P. Singh, Aakash Chawade, Arun K. Joshi and Pawan K. Singh
Plants 2021, 10(12), 2693; https://doi.org/10.3390/plants10122693 - 8 Dec 2021
Cited by 11 | Viewed by 3042
Abstract
Wheat blast (WB) disease, since its first identification in Bangladesh in 2016, is now an established serious threat to wheat production in South Asia. There is a need for sound knowledge about resistance sources and associated genomic regions to assist breeding programs. Hence, [...] Read more.
Wheat blast (WB) disease, since its first identification in Bangladesh in 2016, is now an established serious threat to wheat production in South Asia. There is a need for sound knowledge about resistance sources and associated genomic regions to assist breeding programs. Hence, a panel of genotypes from India and Bangladesh was evaluated for wheat blast resistance and a genome-wide association study (GWAS) was performed. Disease evaluation was done during five crop seasons—at precision phenotyping platform (PPPs) for wheat blast disease at Jashore (2018–19), Quirusillas (2018–19 and 2019–20) and Okinawa (2019 and 2020). Single nucleotide polymorphisms (SNP) across the genome were obtained using DArTseq genotyping-by-sequencing platform, and in total 5713 filtered markers were used. GWAS revealed 40 significant markers associated with WB resistance, of which 33 (82.5%) were in the 2NS/2AS chromosome segment and one each on seven chromosomes (3B, 3D, 4A, 5A, 5D, 6A and 6B). The 2NS markers contributed significantly in most of the environments, explaining an average of 33.4% of the phenotypic variation. Overall, 22.4% of the germplasm carried 2NS/2AS segment. So far, 2NS translocation is the only effective WB resistance source being used in the breeding programs of South Asia. Nevertheless, the identification of non-2NS/2AS genomic regions for WB resistance provides a hope to broaden and diversify resistance for this disease in years to come. Full article
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28 pages, 4781 KiB  
Article
Genetic Analysis of Early White Quality Protein Maize Inbreds and Derived Hybrids under Low-Nitrogen and Combined Drought and Heat Stress Environments
by Olatunde A. Bhadmus, Baffour Badu-Apraku, Oyenike A. Adeyemo and Adebayo L. Ogunkanmi
Plants 2021, 10(12), 2596; https://doi.org/10.3390/plants10122596 - 26 Nov 2021
Cited by 10 | Viewed by 2159
Abstract
An increase in the average global temperature and drought is anticipated in sub-Saharan Africa (SSA) as a result of climate change. Therefore, early white quality protein maize (QPM) hybrids with tolerance to combined drought and heat stress (CDHS) as well as low soil [...] Read more.
An increase in the average global temperature and drought is anticipated in sub-Saharan Africa (SSA) as a result of climate change. Therefore, early white quality protein maize (QPM) hybrids with tolerance to combined drought and heat stress (CDHS) as well as low soil nitrogen (low-nitrogen) have the potential to mitigate the adverse effects of climate change. Ninety-six early QPM hybrids and four checks were evaluated in Nigeria for two years under CDHS, low-nitrogen, and in optimal environments. The objectives of this study were to determine the gene action conditioning grain yield, assess the performance of the early QPM inbred lines and identify high yielding and stable QPM hybrids under CDHS, low-nitrogen and optimal environment conditions. There was preponderance of the non-additive gene action over the additive in the inheritance of grain yield under CDHS environment conditions, while additive gene action was more important for grain yield in a low-nitrogen environment. TZEQI 6 was confirmed as an inbred tester under low N while TZEQI 113 × TZEQI 6 was identified as a single-cross tester under low-nitrogen environments. Plant and ear aspects were the primary contributors to grain yield under CDHS and low-nitrogen environments. TZEQI 6 × TZEQI 228 and the check TZEQI 39 × TZEQI 44 were the highest yielding under each stress environment and across environments. Hybrid TZEQI 210 × TZEQI 188 was the most stable across environments and should be tested on-farm and commercialized in SSA. Full article
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22 pages, 3955 KiB  
Article
Variation in Gene Expression between Two Sorghum bicolor Lines Differing in Innate Immunity Response
by Yaya Cui, Dongqin Chen, Yuexu Jiang, Dong Xu, Peter Balint-Kurti and Gary Stacey
Plants 2021, 10(8), 1536; https://doi.org/10.3390/plants10081536 - 27 Jul 2021
Cited by 3 | Viewed by 3459
Abstract
Microbe associated molecular pattern (MAMPs) triggered immunity (MTI) is a key component of the plant innate immunity response to microbial recognition. However, most of our current knowledge of MTI comes from model plants (i.e., Arabidopsis thaliana) with comparatively less work done using [...] Read more.
Microbe associated molecular pattern (MAMPs) triggered immunity (MTI) is a key component of the plant innate immunity response to microbial recognition. However, most of our current knowledge of MTI comes from model plants (i.e., Arabidopsis thaliana) with comparatively less work done using crop plants. In this work, we studied the MAMP triggered oxidative burst (ROS) and the transcriptional response in two Sorghum bicolor genotypes, BTx623 and SC155-14E. SC155-14E is a line that shows high anthracnose resistance and the line BTx623 is susceptible to anthracnose. Our results revealed a clear variation in gene expression and ROS in response to either flagellin (flg22) or chitin elicitation between the two lines. While the transcriptional response to each MAMP and in each line was unique there was a considerable degree of overlap, and we were able to define a core set of genes associated with the sorghum MAMP transcriptional response. The GO term and KEGG pathway enrichment analysis discovered more immunity and pathogen resistance related DEGs in MAMP treated SC155-14E samples than in BTx623 with the same treatment. The results provide a baseline for future studies to investigate innate immunity pathways in sorghum, including efforts to enhance disease resistance. Full article
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13 pages, 2108 KiB  
Communication
Rice Sesquiterpene Plays Important Roles in Antixenosis against Brown Planthopper in Rice
by Wintai Kamolsukyeunyong, Wissarut Sukhaket, Kitsada Pitija, Pornwalai Thorngkham, Sugunya Mahatheeranont, Theerayut Toojinda and Apichart Vanavichit
Plants 2021, 10(6), 1049; https://doi.org/10.3390/plants10061049 - 22 May 2021
Cited by 6 | Viewed by 3167
Abstract
The rice sesquiterpene synthase II gene (OsSTPS2, LOC_Os04g27430), which is involved in the antixenosis defense mechanism of rice against brown planthopper (BPH) infestation, was identified in the BPH-resistant rice variety Rathu Heenati (RH). In contrast, the gene was not functional in [...] Read more.
The rice sesquiterpene synthase II gene (OsSTPS2, LOC_Os04g27430), which is involved in the antixenosis defense mechanism of rice against brown planthopper (BPH) infestation, was identified in the BPH-resistant rice variety Rathu Heenati (RH). In contrast, the gene was not functional in the BPH-susceptible rice variety KDML105 (KD). Single-nucleotide polymorphisms (SNPs) in the promoter region and in exon 5 of the gene and a seven amino acid deletion in the deduced protein sequence are suggested as factors that negatively regulate the function of the gene. Sequence analysis of the promoter region and expression analysis of the OsSTPS2 gene in several rice genotypes revealed the correlation of SNPs of the ATHB-1, SBE1, and P-factor with the expression of the gene. Genomic and complementary DNA (cDNA) sequence analysis at exon 5 of the gene showed that the 21 bp deletion naturally occurred in several rice genotypes. The antixenosis of the BPH feeding preference (AFP) of rice varieties differed in the seven amino acid deletion lesion of the gene, suggesting that the seven amino acid deletion negatively controls the antixenosis mechanism during BPH infestation. Analysis of the plant volatile compounds released after BPH infestation suggested that E-β-farnesene (EBF) is the major product of the OsSTPS2 gene. Full article
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26 pages, 12072 KiB  
Article
Meta-Analysis of Quantitative Traits Loci (QTL) Identified in Drought Response in Rice (Oryza sativa L.)
by Nurhanis Selamat and Kalaivani K. Nadarajah
Plants 2021, 10(4), 716; https://doi.org/10.3390/plants10040716 - 7 Apr 2021
Cited by 33 | Viewed by 4975
Abstract
Rice is an important grain that is the staple food for most of the world’s population. Drought is one of the major stresses that negatively affects rice yield. The nature of drought tolerance in rice is complex as it is determined by various [...] Read more.
Rice is an important grain that is the staple food for most of the world’s population. Drought is one of the major stresses that negatively affects rice yield. The nature of drought tolerance in rice is complex as it is determined by various components and has low heritability. Therefore, to ensure success in breeding programs for drought tolerant rice, QTLs (quantitative trait loci) of interest must be stable in a variety of plant genotypes and environments. This study identified stable QTLs in rice chromosomes in a variety of backgrounds and environments and conducted a meta-QTL analysis of stable QTLs that have been reported by previous research for use in breeding programs. A total of 653 QTLs for drought tolerance in rice from 27 genetic maps were recorded for analysis. The QTLs recorded were related to 13 traits in rice that respond to drought. Through the use of BioMercartor V4.2, a consensus map containing QTLs and molecular markers were generated using 27 genetic maps that were extracted from the previous 20 studies and meta-QTL analysis was conducted on the consensus map. A total of 70 MQTLs were identified and a total of 453 QTLs were mapped into the meta-QTL areas. Five meta-QTLs from chromosome 1 (MQTL 1.5 and MQTL 1.6), chromosome 2 (MQTL2.1 and MQTL 2.2) and chromosome 3 (MQTL 3.1) were selected for functional annotation as these regions have high number of QTLs and include many traits in rice that respond to drought. A number of genes in MQTL1.5 (268 genes), MQTL1.6 (640 genes), MQTL 2.1 (319 genes), MQTL 2.2 (19 genes) and MQTL 3.1 (787 genes) were annotated through Blast2GO. Few major proteins that respond to drought stress were identified in the meta-QTL areas which are Abscisic Acid-Insensitive Protein 5 (ABI5), the G-box binding factor 4 (GBF4), protein kinase PINOID (PID), histidine kinase 2 (AHK2), protein related to autophagy 18A (ATG18A), mitochondrial transcription termination factor (MTERF), aquaporin PIP 1-2, protein detoxification 48 (DTX48) and inositol-tetrakisphosphate 1-kinase 2 (ITPK2). These proteins are regulatory proteins involved in the regulation of signal transduction and gene expression that respond to drought stress. The meta-QTLs derived from this study and the genes that have been identified can be used effectively in molecular breeding and in genetic engineering for drought resistance/tolerance in rice. Full article
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14 pages, 2565 KiB  
Article
Functional Analysis of Organic Acids on Different Oilseed Rape Species in Phytoremediation of Cadmium Pollution
by Shi Li, Sixiu Le, Xin Wang, Jiuyuan Bai, Rui Wang and Yun Zhao
Plants 2020, 9(7), 884; https://doi.org/10.3390/plants9070884 - 13 Jul 2020
Cited by 10 | Viewed by 2879
Abstract
Cadmium (Cd) pollution in soil is becoming increasingly serious due to anthropogenic activities, which not only poses a threat to the ecological environment, but also causes serious damage to human health via the biological chain. Consequently, special concerns should be paid to develop [...] Read more.
Cadmium (Cd) pollution in soil is becoming increasingly serious due to anthropogenic activities, which not only poses a threat to the ecological environment, but also causes serious damage to human health via the biological chain. Consequently, special concerns should be paid to develop and combine multiple remediation strategies. In this study, different subspecies of oilseed rape, Brassica campestris, Brassica napus and Brassica juncea were applied, combined with three organic acids, acetic acid, oxalic acid and citric acid, in a simulated Cd-contaminated soil. Various physiological and biochemical indexes were monitored in both plant seedling, growth period and mature stage. The results showed that organic acids significantly promoted the growth of Brassica campestris and Brassica juncea under Cd stress. The photosynthesis and antioxidant enzyme activities in Brassica campestris and Brassica juncea were induced at seedling stage, while that in Brassica napus were suppressed and disturbed. The enrichment of Cd in oilseed rape was also obviously increased. Brassica juncea contained relatively high resistance and Cd content in plant but little Cd in seed. Among the three acids, oxalic acids exhibited the most efficient promoting effect on the accumulation of Cd by oilseed rape. Here, a comprehensive study on the combined effects of oilseed rape and organic acids on Cd contaminated soil showed that Brassica juncea and oxalic acid possessed the best effect on phytoremediation of Cd contaminated soil. Our study provides an optimal way of co-utilizing oilseed rape and organic acid in phytoremediation of Cd contaminated soil. Full article
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Review

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21 pages, 679 KiB  
Review
Importance of Landraces in Cereal Breeding for Stress Tolerance
by Daniela Marone, Maria A. Russo, Antonia Mores, Donatella B. M. Ficco, Giovanni Laidò, Anna M. Mastrangelo and Grazia M. Borrelli
Plants 2021, 10(7), 1267; https://doi.org/10.3390/plants10071267 - 22 Jun 2021
Cited by 65 | Viewed by 7920
Abstract
The renewed focus on cereal landraces is a response to some negative consequences of modern agriculture and conventional breeding which led to a reduction of genetic diversity. Cereal landraces are still cultivated on marginal lands due to their adaptability to unfavourable conditions, constituting [...] Read more.
The renewed focus on cereal landraces is a response to some negative consequences of modern agriculture and conventional breeding which led to a reduction of genetic diversity. Cereal landraces are still cultivated on marginal lands due to their adaptability to unfavourable conditions, constituting an important source of genetic diversity usable in modern plant breeding to improve the adaptation to abiotic or biotic stresses, yield performance and quality traits in limiting environments. Traditional agricultural production systems have played an important role in the evolution and conservation of wide variability in gene pools within species. Today, on-farm and ex situ conservation in gene bank collections, together with data sharing among researchers and breeders, will greatly benefit cereal improvement. Many efforts are usually made to collect, organize and phenotypically and genotypically analyse cereal landrace collections, which also utilize genomic approaches. Their use in breeding programs based on genomic selection, and the discovery of beneficial untapped QTL/genes/alleles which could be introgressed into modern varieties by MAS, pyramiding or biotechnological tools, increase the potential for their better deployment and exploitation in breeding for a more sustainable agricultural production, particularly enhancing adaptation and productivity in stress-prone environments to cope with current climate changes. Full article
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25 pages, 920 KiB  
Review
From Genetic Maps to QTL Cloning: An Overview for Durum Wheat
by Pasqualina Colasuonno, Ilaria Marcotuli, Agata Gadaleta and Jose Miguel Soriano
Plants 2021, 10(2), 315; https://doi.org/10.3390/plants10020315 - 6 Feb 2021
Cited by 29 | Viewed by 5655
Abstract
Durum wheat is one of the most important cultivated cereal crops, providing nutrients to humans and domestic animals. Durum breeding programs prioritize the improvement of its main agronomic traits; however, the majority of these traits involve complex characteristics with a quantitative inheritance (quantitative [...] Read more.
Durum wheat is one of the most important cultivated cereal crops, providing nutrients to humans and domestic animals. Durum breeding programs prioritize the improvement of its main agronomic traits; however, the majority of these traits involve complex characteristics with a quantitative inheritance (quantitative trait loci, QTL). This can be solved with the use of genetic maps, new molecular markers, phenotyping data of segregating populations, and increased accessibility to sequences from next-generation sequencing (NGS) technologies. This allows for high-density genetic maps to be developed for localizing candidate loci within a few Kb in a complex genome, such as durum wheat. Here, we review the identified QTL, fine mapping, and cloning of QTL or candidate genes involved in the main traits regarding the quality and biotic and abiotic stresses of durum wheat. The current knowledge on the used molecular markers, sequence data, and how they changed the development of genetic maps and the characterization of QTL is summarized. A deeper understanding of the trait architecture useful in accelerating durum wheat breeding programs is envisioned. Full article
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33 pages, 3365 KiB  
Review
Updating the Breeding Philosophy of Wheat to Fusarium Head Blight (FHB): Resistance Components, QTL Identification, and Phenotyping—A Review
by Akos Mesterhazy
Plants 2020, 9(12), 1702; https://doi.org/10.3390/plants9121702 - 3 Dec 2020
Cited by 49 | Viewed by 4512
Abstract
Fusarium head blight has posed continuous risks to wheat production worldwide due to its effects on yield, and the fungus provides additional risks with production of toxins. Plant resistance is thought to be the most powerful method. The host plant resistance is complex, [...] Read more.
Fusarium head blight has posed continuous risks to wheat production worldwide due to its effects on yield, and the fungus provides additional risks with production of toxins. Plant resistance is thought to be the most powerful method. The host plant resistance is complex, Types I–V were reported. From the time of spraying inoculation (Type I), all resistance types can be identified and used to determine the total resistance. Type II resistance (at point inoculation) describes the spread of head blight from the ovary to the other parts of the head. Therefore, it cannot solve the resistance problem alone. Type II QTL (quantitative trait locus) Fhb1 on 3BS from Sumai 3 descendant CM82036 secures about the same resistance level as Type I QTL does on 5AS and 5ASc in terms of visual symptoms, FDK (Fusarium damaged kernel), and deoxynivalenol response. Recently, increasing evidence supports the association of deoxynivalenol (DON) content and low kernel infection with FHB (Fusarium head blight) resistance (Types III and IV), as QTL for individual resistance types has been identified. In plant breeding practice, the role of visual selection remains vital, but the higher correlations for FDK/DON make it possible to select low-DON genotypes via FDK value. For phenotyping, the use of more independent inocula (isolates or mixtures) makes resistance evaluation more reliable. The large heterogeneity of the mapping populations is a serious source of underestimating genetic effects. Therefore, the increasing of homogeneity is a necessity. As no wheat varieties exist with full resistance to FHB, crops must be supported by proper agronomy and fungicide use. Full article
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