المؤلفون: Veronica F. Guwela, Martin R. Broadley, Malcolm J. Hawkesford, Moses F. A. Maliro, James Bokosi, Mike Banda, Surbhi Grewal, Lolita Wilson, Julie King

المصدر: Frontiers in Agronomy, Vol 6 (2024)

مصطلحات موضوعية: wheat, micronutrients, biofortification, wild relatives, soil pH, organic matter, Agriculture, Plant culture, SB1-1110

الوصف: The concentration of mineral nutrients in plants is associated with bioavailabilities of soil mineral nutrients, which are regulated by various soil physio-chemical properties. A pot experiment was conducted to investigate the effects of soil type on grain and straw zinc (Zn), iron (Fe) and selenium (Se) concentrations of wheat/Amblyopyrum muticum and wheat/Triticum urartu doubled haploid lines. A set of 42 treatments in a factorial combination with 21 genotypes and two soil types collected from Ngabu and Chitedze Research Stations in Malawi was laid in a randomised complete block design (RCBD) in three replicates. Pre-experiment soil Zn and Fe were extracted using DTPA extraction method followed by analysis with inductively coupled plasma-mass spectrometry (ICP-MS). Aqua-regia hotplate acid digestion was used to extract soil Se and analysis was done using ICPM-MS. Grain and straw samples were digested using nitric acid digestion (HNO3) and analysed using ICP-MS. Soil analysis results showed that the two soils had the same textural class (Sandy clay loam), but different mineral concentrations, pH levels and percentage organic matter. Analysis of variance revealed a ~two-fold higher Zn concentration in grains grown in low pH, high Zn soils (Chitedze soils) compared to grains grown in high pH, low Zn soils (Ngabu soils). Variation in grain Zn concentration was associated with the genotypes (p = 0002), soil type (p =

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fagro.2024.1305034/fullTest; https://doaj.org/toc/2673-3218Test

الوصول الحر: https://doaj.org/article/67b71bd8fd914fe8868f9814d4947fc0Test

المؤلفون: Yan WANG, Zhen-ru GUO, Qing CHEN, Yang LI, Kan ZHAO, Yong-fang WAN, Malcolm J. HAWKESFORD, Yun-feng JIANG, Li KONG, Zhi-en PU, Mei DENG, Qian-tao JIANG, Xiu-jin LAN, Ji-rui WANG, Guo-yue CHEN, Jian MA, You-liang ZHENG, Yu-ming WEI, Peng-fei QI

المصدر: Journal of Integrative Agriculture, Vol 22, Iss 6, Pp 1609-1617 (2023)

مصطلحات موضوعية: HMW-GS, nonsense mutation, Dy10-null allele, end-use quality, Agriculture (General), S1-972

الوصف: High-molecular-weight glutenin subunits (HMW-GSs) are the most critical grain storage proteins that determine the unique processing qualities of wheat. Although it is a part of the superior HMW-GS pair (Dx5+Dy10), the contribution of the Dy10 subunit to wheat processing quality remains unclear. In this study, we elucidated the effect of Dy10 on wheat processing quality by generating and analyzing a deletion mutant (with the Dy10-null allele), and by elucidating the changes to wheat flour following the incorporation of purified Dy10. The Dy10-null allele was transcribed normally, but the Dy10 subunit was lacking. These findings implied that the Dy10-null allele reduced the glutenin:gliadin ratio and negatively affected dough strength (i.e., Zeleny sedimentation value, gluten index, and dough development and stability times) and the bread-making quality; however, it positively affected the biscuit-making quality. The incorporation of various amounts of purified Dy10 into wheat flour had a detrimental effect on biscuit-making quality. The results of this study demonstrate that the Dy10 subunit is essential for maintaining wheat dough strength. Furthermore, the Dy10-null allele may be exploited by soft wheat breeding programs.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2095311922001198Test; https://doaj.org/toc/2095-3119Test

الوصول الحر: https://doaj.org/article/abcaabbd2f6746f48820a8f011fd34e1Test

المؤلفون: Sandeep Sharma, Tarun Kumar, M. John Foulkes, Simon Orford, Anju Mahendru Singh, Luzie U. Wingen, Venkatesh Karnam, Lekshmy S. Nair, Pranab Kumar Mandal, Simon Griffiths, Malcolm J. Hawkesford, Peter R. Shewry, Alison R. Bentley, Renu Pandey

المصدر: CABI Agriculture and Bioscience, Vol 4, Iss 1, Pp 1-20 (2023)

مصطلحات موضوعية: Biomass partitioning, Grain protein concentration, Grain protein deviation, Low soil nitrogen, Nitrogen remobilization efficiency, Triticum aestivum, Agriculture (General), S1-972

الوصف: Abstract Background In wheat, nitrogen (N) remobilization from vegetative tissues to developing grains largely depends on genetic and environmental factors. The evaluation of genetic potential of crops under limited resource inputs such as limited N supply would provide an opportunity to identify N-efficient lines with improved N utilisation efficiency and yield potential. We assessed the genetic variation in wheat recombinant inbred lines (RILs) for uptake, partitioning, and remobilization of N towards grain, its association with grain protein concentration (GPC) and grain yield. Methods We used the nested association mapping (NAM) population (195 lines) derived by crossing Paragon (P) with CIMMYT core germplasm (P × Cim), Baj (P × Baj), Watkins (P × Wat), and Wyalkatchem (P × Wya). These lines were evaluated in the field for two seasons under limited N supply. The plant sampling was done at anthesis and physiological maturity stages. Various physiological traits were recorded and total N uptake and other N related indices were calculated. The grain protein deviation (GPD) was calculated from the regression of grain yield on GPC. These lines were grouped into different clusters by hierarchical cluster analysis based on grain yield and N-remobilization efficiency (NRE). Results The genetic variation in accumulation of biomass at both pre- and post-anthesis stages were correlated with grain-yield. The NRE significantly correlated with aboveground N uptake at anthesis (AGNa) and grain yield but negatively associated with AGN at post-anthesis (AGNpa) suggesting higher N uptake till anthesis favours high N remobilization during grain filling. Hierarchical cluster analysis of these RILs based on NRE and yield resulted in four clusters, efficient (31), moderately efficient (59), moderately inefficient (58), and inefficient (47). In the N-efficient lines, AGNa contributed to 77% of total N accumulated in grains, while it was 63% in N-inefficient lines. Several N-efficient lines also exhibited positive grain protein deviation (GPD), combining high grain yield and GPC. Among crosses, the P × Cim were superior and N-efficient, while P × Wya responded poorly to low N input. Conclusions We propose that traits favouring pre- or post-anthesis biomass accumulation and pre-anthesis N uptake may be targeted for breeding to improve grain-yield under limited N. The lines with positive GPD, a first report of genotype-dependent GPD associated with both AGNpa and AGNa in wheat, may be used as varieties or genetic resources to improve grain yield with high GPC for sustainable development under limited N conditions.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2662-4044Test

الوصول الحر: https://doaj.org/article/1a4ec08c7ef642b0b4c57685adf170f4Test

المؤلفون: Daniel K. Cudjoe, Nicolas Virlet, March Castle, Andrew B. Riche, Manal Mhada, Toby W. Waine, Fady Mohareb, Malcolm J. Hawkesford

المصدر: Frontiers in Plant Science, Vol 14 (2023)

مصطلحات موضوعية: African crops, phenotypes, field phenotyping, high-throughput phenotyping, phenotyping infrastructures, low-cost phenotyping, Plant culture, SB1-1110

الوصف: Improvements in crop productivity are required to meet the dietary demands of the rapidly-increasing African population. The development of key staple crop cultivars that are high-yielding and resilient to biotic and abiotic stresses is essential. To contribute to this objective, high-throughput plant phenotyping approaches are important enablers for the African plant science community to measure complex quantitative phenotypes and to establish the genetic basis of agriculturally relevant traits. These advances will facilitate the screening of germplasm for optimum performance and adaptation to low-input agriculture and resource-constrained environments. Increasing the capacity to investigate plant function and structure through non-invasive technologies is an effective strategy to aid plant breeding and additionally may contribute to precision agriculture. However, despite the significant global advances in basic knowledge and sensor technology for plant phenotyping, Africa still lags behind in the development and implementation of these systems due to several practical, financial, geographical and political barriers. Currently, field phenotyping is mostly carried out by manual methods that are prone to error, costly, labor-intensive and may come with adverse economic implications. Therefore, improvements in advanced field phenotyping capabilities and appropriate implementation are key factors for success in modern breeding and agricultural monitoring. In this review, we provide an overview of the current state of field phenotyping and the challenges limiting its implementation in some African countries. We suggest that the lack of appropriate field phenotyping infrastructures is impeding the development of improved crop cultivars and will have a detrimental impact on the agricultural sector and on food security. We highlight the prospects for integrating emerging and advanced low-cost phenotyping technologies into breeding protocols and characterizing crop responses to environmental challenges in field experimentation. Finally, we explore strategies for overcoming the barriers and maximizing the full potential of emerging field phenotyping technologies in African agriculture. This review paper will open new windows and provide new perspectives for breeders and the entire plant science community in Africa.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fpls.2023.1219673/fullTest; https://doaj.org/toc/1664-462XTest

الوصول الحر: https://doaj.org/article/81cb63785f784c1eb58da5dadcb30464Test

المؤلفون: Petros P. Sigalas, Peter Buchner, Alex Kröper, Malcolm J. Hawkesford

المصدر: International Journal of Molecular Sciences, Vol 25, Iss 1, p 509 (2023)

مصطلحات موضوعية: NRT2, NRT3, nitrate, nitrogen, wheat, gene expression, Biology (General), QH301-705.5, Chemistry, QD1-999

الوصف: High-affinity nitrate transporters (NRT) are key components for nitrogen (N) acquisition and distribution within plants. However, insights on these transporters in wheat are scarce. This study presents a comprehensive analysis of the NRT2 and NRT3 gene families, where the aim is to shed light on their functionality and to evaluate their responses to N availability. A total of 53 NRT2s and 11 NRT3s were identified in the bread wheat genome, and these were grouped into different clades and homoeologous subgroups. The transcriptional dynamics of the identified NRT2 and NRT3 genes, in response to N starvation and nitrate resupply, were examined by RT-qPCR in the roots and shoots of hydroponically grown wheat plants through a time course experiment. Additionally, the spatial expression patterns of these genes were explored within the plant. The NRT2s of clade 1, TaNRT2.1-2.6, showed a root-specific expression and significant upregulation in response to N starvation, thus emphasizing a role in N acquisition. However, most of the clade 2 NRT2s displayed reduced expression under N-starved conditions. Nitrate resupply after N starvation revealed rapid responsiveness in TaNRT2.1-2.6, while clade 2 genes exhibited gradual induction, primarily in the roots. TaNRT2.18 was highly expressed in above-ground tissues and exhibited distinct nitrate-related response patterns for roots and shoots. The TaNRT3 gene expression closely paralleled the profiles of TaNRT2.1-2.6 in response to nitrate induction. These findings enhance the understanding of NRT2 and NRT3 involvement in nitrogen uptake and utilization, and they could have practical implications for improving nitrogen use efficiency. The study also recommends a standardized nomenclature for wheat NRT2 genes, thereby addressing prior naming inconsistencies.

وصف الملف: electronic resource

العلاقة: https://www.mdpi.com/1422-0067/25/1/509Test; https://doaj.org/toc/1661-6596Test; https://doaj.org/toc/1422-0067Test

الوصول الحر: https://doaj.org/article/b2479099757845c0b3957aab6da7527cTest

المؤلفون: Hu Zhou, Andrew B. Riche, Malcolm J. Hawkesford, William R. Whalley, Brian S. Atkinson, Craig J. Sturrock, Sacha J. Mooney

المصدر: Plant Methods, Vol 17, Iss 1, Pp 1-9 (2021)

مصطلحات موضوعية: Wheat ear, Wheat grain, X-ray microtomography, Plant culture, SB1-1110, Biology (General), QH301-705.5

الوصف: Abstract Background Wheat spike architecture is a key determinant of multiple grain yield components and detailed examination of spike morphometric traits is beneficial to explain wheat grain yield and the effects of differing agronomy and genetics. However, quantification of spike morphometric traits has been very limited because it relies on time-consuming manual measurements. Results In this study, using X-ray Computed Tomography imaging, we proposed a method to efficiently detect the 3D architecture of wheat spikes and component spikelets by clustering grains based on their Euclidean distance and relative positions. Morphometric characteristics of wheat spikelets and grains, e.g., number, size and spatial distribution along the spike can be determined. Two commercial wheat cultivars, one old, Maris Widgeon, and one modern, Siskin, were studied as examples. The average grain volume of Maris Widgeon and Siskin did not differ, but Siskin had more grains per spike and therefore greater total grain volume per spike. The spike length and spikelet number were not statistically different between the two cultivars. However, Siskin had a higher spikelet density (number of spikelets per unit spike length), with more grains and greater grain volume per spikelet than Maris Widgeon. Spatial distribution analysis revealed the number of grains, the average grain volume and the total grain volume of individual spikelets varied along the spike. Siskin had more grains and greater grain volumes per spikelet from spikelet 6, but not spikelet 1–5, compared with Maris Widgeon. The distribution of average grain volume along the spike was similar for the two wheat cultivars. Conclusion The proposed method can efficiently extract spike, spikelet and grain morphometric traits of different wheat cultivars, which can contribute to a more detailed understanding of the sink of wheat grain yield.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/1746-4811Test

الوصول الحر: https://doaj.org/article/4e1fad0adde4421dad667b89911aa145Test

المؤلفون: Sinda Ben Mariem, Angie L. Gámez, Luis Larraya, Teresa Fuertes-Mendizabal, Nuria Cañameras, José L. Araus, Steve P. McGrath, Malcolm J. Hawkesford, Carmen Gonzalez Murua, Myriam Gaudeul, Leopoldo Medina, Alan Paton, Luigi Cattivelli, Andreas Fangmeier, James Bunce, Sabine Tausz-Posch, Andy J. Macdonald, Iker Aranjuelo

المصدر: Scientific Reports, Vol 10, Iss 1, Pp 1-13 (2020)

مصطلحات موضوعية: Medicine, Science

الوصف: Abstract The current study focuses on yield and nutritional quality changes of wheat grain over the last 166 years. It is based on wheat grain quality analyses carried out on samples collected between 1850 and 2016. Samples were obtained from the Broadbalk Continuous Wheat Experiment (UK) and from herbaria from 16 different countries around the world. Our study showed that, together with an increase in carbohydrate content, an impoverishment of mineral composition and protein content occurred. The imbalance in carbohydrate/protein content was specially marked after the 1960’s, coinciding with strong increases in ambient [CO2] and temperature and the introduction of progressively shorter straw varieties. The implications of altered crop physiology are discussed.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2045-2322Test

الوصول الحر: https://doaj.org/article/ba953d41a51d4b76b21a0b511b5a75d9Test

المؤلفون: Monika Huber, Laura Armbruster, Ross D. Etherington, Carolina De La Torre, Malcolm J. Hawkesford, Carsten Sticht, Daniel J. Gibbs, Rüdiger Hell, Markus Wirtz

المصدر: Frontiers in Plant Science, Vol 12 (2022)

مصطلحات موضوعية: N-terminal acetylation, co-translational modification, N-acetyltransferase NatB, ER-associated degradation, DOA10, proteostasis, Plant culture, SB1-1110

الوصف: In Arabidopsis thaliana, the evolutionary conserved N-terminal acetyltransferase (Nat) complexes NatA and NatB co-translationally acetylate 60% of the proteome. Both have recently been implicated in the regulation of plant stress responses. While NatA mediates drought tolerance, NatB is required for pathogen resistance and the adaptation to high salinity and high osmolarity. Salt and osmotic stress impair protein folding and result in the accumulation of misfolded proteins in the endoplasmic reticulum (ER). The ER-membrane resident E3 ubiquitin ligase DOA10 targets misfolded proteins for degradation during ER stress and is conserved among eukaryotes. In yeast, DOA10 recognizes conditional degradation signals (Ac/N-degrons) created by NatA and NatB. Assuming that this mechanism is preserved in plants, the lack of Ac/N-degrons required for efficient removal of misfolded proteins might explain the sensitivity of NatB mutants to protein harming conditions. In this study, we investigate the response of NatB mutants to dithiothreitol (DTT) and tunicamycin (TM)-induced ER stress. We report that NatB mutants are hypersensitive to DTT but not TM, suggesting that the DTT hypersensitivity is caused by an over-reduction of the cytosol rather than an accumulation of unfolded proteins in the ER. In line with this hypothesis, the cytosol of NatB depleted plants is constitutively over-reduced and a global transcriptome analysis reveals that their reductive stress response is permanently activated. Moreover, we demonstrate that doa10 mutants are susceptible to neither DTT nor TM, ruling out a substantial role of DOA10 in ER-associated protein degradation (ERAD) in plants. Contrary to previous findings in yeast, our data indicate that N-terminal acetylation (NTA) does not inhibit ER targeting of a substantial amount of proteins in plants. In summary, we provide further evidence that NatB-mediated imprinting of the proteome is vital for the response to protein harming stress and rule out DOA10 as the sole recognin for substrates in the plant ERAD pathway, leaving the role of DOA10 in plants ambiguous.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fpls.2021.799954/fullTest; https://doaj.org/toc/1664-462XTest

الوصول الحر: https://doaj.org/article/c5de67b713d7426ca684b3bc4ee020d1Test

المؤلفون: Wanneng Yang, John H. Doonan, Malcolm J. Hawkesford, Tony Pridmore, Ji Zhou

المصدر: Frontiers in Plant Science, Vol 12 (2021)

مصطلحات موضوعية: high-throughput phenotyping, AI-driven phenotypic analysis, UAV (unmanned aerial vehicle), hyperspectral, X-ray micro-CT, Plant culture, SB1-1110

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fpls.2021.767324/fullTest; https://doaj.org/toc/1664-462XTest

الوصول الحر: https://doaj.org/article/004ca56283bc48f6bb5d7beafeb86874Test

المؤلفون: Rahul B. Nitnavare, Joorie Bhattacharya, Satnam Singh, Amardeep Kour, Malcolm J. Hawkesford, Naveen Arora

المصدر: Frontiers in Plant Science, Vol 12 (2021)

مصطلحات موضوعية: RNAi silencing, dsRNA, siRNA, coleopteran, hemipteran, lepidopteran, Plant culture, SB1-1110

الوصف: RNA interference (RNAi) is a method of gene silencing where dsRNA is digested into small interfering RNA (siRNA) in the presence of enzymes. These siRNAs then target homologous mRNA sequences aided by the RNA-induced silencing complex (RISC). The mechanism of dsRNA uptake has been well studied and established across many living organisms including insects. In insects, RNAi is a novel and potential tool to develop future pest management means targeting various classes of insects including dipterans, coleopterans, hemipterans, lepidopterans, hymenopterans and isopterans. However, the extent of RNAi in individual class varies due to underlying mechanisms. The present review focuses on three major insect classes viz hemipterans, lepidopterans and coleopterans and the rationale behind this lies in the fact that studies pertaining to RNAi has been extensively performed in these groups. Additionally, these classes harbour major agriculturally important pest species which require due attention. Interestingly, all the three classes exhibit varying levels of RNAi efficiencies with the coleopterans exhibiting maximum response, while hemipterans are relatively inefficient. Lepidopterans on the other hand, show minimum response to RNAi. This has been attributed to many facts and few important being endosomal escape, high activity dsRNA-specific nucleases, and highly alkaline gut environment which renders the dsRNA unstable. Various methods have been established to ensure safe delivery of dsRNA into the biological system of the insect. The most common method for dsRNA administration is supplementing the diet of insects via spraying onto leaves and other commonly eaten parts of the plant. This method is environment-friendly and superior to the hazardous effects of pesticides. Another method involves submergence of root systems in dsRNA solutions and subsequent uptake by the phloem. Additionally, more recent techniques are nanoparticle- and Agrobacterium-mediated delivery systems. However, due to the novelty of these biotechnological methods and recalcitrant nature of certain crops, further optimization is required. This review emphasizes on RNAi developments in agriculturally important insect species and the major hurdles for efficient RNAi in these groups. The review also discusses in detail the development of new techniques to enhance RNAi efficiency using liposomes and nanoparticles, transplastomics, microbial-mediated delivery and chemical methods.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fpls.2021.673576/fullTest; https://doaj.org/toc/1664-462XTest

الوصول الحر: https://doaj.org/article/e2f0f78849324c95bdd65472ef1127e8Test