Screening and evaluation for antibiosis resistance of the spring wheat accessions to the grain aphid,Sitobion miscanthi(Takahashi)(Hemiptera:Aphididae)

Resistant cultivar deployment is an effective method for cereal aphid management.Under greenhouse conditions,preliminary antibiosis resistance screening was conducted on 114 Ethiopian and 22 Chinese spring wheat accessions.After performing a bioassay to determine antibiosis resistance,aphid feeding behaviour and phenolic acid content analyses were performed on the aphid resistant wheat accessions by electrical penetration graph(EPG)and high performance liquid chromatography(HPLC),respectively.Among the wheat accessions,two high resistances,27moderate-resistances,and 35 low-resistances to Sitobion miscanthi were identified.The antibiosis resistance test showed prolonged pre-adult and pre-reproductive periods,shorter reproductive periods,lower fecundity,an intrinsic rate(rm)of increase,and a finite rate(λ)of increase of S.miscanthi on Lunxuan 145,Wane,Lunxuan 6,204511,Lunxuan 103and 5215 than those on the aphid-susceptible accession Beijing 837.The changes for the parameters of aphid feeding behaviour,including spending a longer time in the penetration and phloem salivation phases and less time in the phloem sap-feeding phase on the resistant wheat accessions,indicated that the aphid resistance may occur during the phloem phase and may be due to difficulties in the mechanical probing of the mesophyll cells.Additionally,the HPLC analysis showed higher contents of:1)ferulic acid in Lunxuan 145,Lunxuan 103 and Lunxuan 6;2)p-coumaric acid in Lunxuan145;3)vanillic acid in Lunxuan 145,Wane and Lunxuan 6;4)syringic acid in Lunxuan 103;and 5)caffeic acid in 5215.The contents of some phenolic acids within wheat leaves,such as p-courmaric acid and vanillic acid showed significant positive correlation with the duration of aphid development,but negative correlation with the aphid fecundity.The concentrations of these acids may be the causes of antibiosis resistance to S.miscanthi.The identification of grain aphid-resistant wheat accessions in our study will be helpful in future breeding program for pest control.

Greenhouse and Field Evaluation of Selected Sweetpotato (<i>Ipomoea batatas</i>(L.) LAM) Accessions for Drought Tolerance in South Africa

Sweetpotato is a major staple food in the world. It is a good source of carbohydrates, vitamin A, vitamin C and protein. The maximum production potential of the crop is being hampered by severe drought which ravages most parts of Africa. The main aim of this study therefore was to screen accessions of sweetpotato for drought tolerance in a quick screening method, followed by field screening with a view to identify accessions that can perform well under water stress conditions. Fifty sweetpotato accessions consisting of cultivars and breeding lines collected from the ARC-VOPI gene bank were planted for drought screening in the glass house for six weeks during which water was withheld to induce stress. Observations were made on number of dead plants and days to wilting point. The results were analyzed and 12 best performing accessions were selected for field trials. The field trial was carried out in Lwamondo, Limpopo province, a drought prone area in South Africa, under rain-fed conditions. The best performing accessions were Zapallo, Tacna, Ejumula, 2004-9-2 and Ndou.

Analyses Using SSR and DArT Molecular Markers Reveal that Ethiopian Accessions of White Lupin (<i>Lupinus albus</i>L.) Represent a Unique Genepool

PCR-based genic and microarray-based Diversity Arrays Technology (DArTTM) markers were used to determine genetic diversity in 94 accessions of white lupin (Lupinus albus L.) comprising Australian and foreign cultivars, landraces, and advanced breeding lines from Australian breeding programs. A total of 345 (50 PCR-based and 295 DArT-based) polymorphic fragments were identified, which were used to determine the genetic diversity among accessions. Both cluster analysis of bivariate marker data using UPGMA, and principal coordinate analysis, indicated a high level of genetic diversity in the germplasm. Our results showed that both types of markers used in this study are suitable for estimation of genetic diversity. Landrace accessions from Ethiopia formed a very distinct and separate grouping with both marker systems. Australian cultivars and breeding lines were clustered together and tended to be distinct from European landraces. These findings will allow breeders to select appropriate, diverse parents to broaden the genetic base of white lupin breeding populations.

Genetic Diversity Analysis of Forty Pearl Millet (<i>Pennisetum glaucum</i>(L.) R. Br) Accessions from Sudan Using Agronomical Descriptors and DNA Molecular Markers

Morphological descriptors and Random Amplification of Polymorphic DNA (RAPD) technique were used to assess the genetic variation among and within forty Pennesitum glaucum accessions from Sudan. Accessions were collected from 30 villages representing Darfur, North Kordofan, South Kordofan, and Blue Nile states. 64 amplified fragments were distinguished using ten primers.? 63 bands were polymorphic among the forty accessions with an average of 6.3 polymorphic bands per primer. Low level of genetic similarity was observed (4% - 43%). The PhiPT (analogue of FST fixation index) value for genetic variability obtained over the four regions was 0.169 with high significance (P = 0.01). AMOVA analysis showed higher variance components within regions (80%) than among regions (20%). The two dendrograms obtained by Random Amplification of Polymorphic DNA (RAPD) data;and morphological data based on 26 descriptors did not fit together. PCA (Principal coordinate’s analysis) showed geographic structuring of pearl millet according to its growing regions in Sudan.

Morphological Characterization of Mango （Mangifera indica） Accessions Based on Brazilian Adapted Descriptors

The aim of this study was to characterize 103 mango accessions of the field germplasm collection of Embrapa semi-arid region, located in Juazeiro, Bahia, Brazil and to apply 50 morphological descriptors established by the Brazilian Ministry of Agriculture, livestock and supply to help in the development of new mango cultivars for the Northeastern region of Brazil. Four trees were selected for each accession and eight adult leaves, eight flowers and 16 fruits were collected from each tree. Morphological characteristics ranging from plant size to seed embryo were evaluated. Simple percentages were estimated for all the descriptors. Only the descriptors for leaf symmetry and fruit waxiness did not show variability among the accessions. Eight accessions did not show fruits with fibers, while nine other accessions presented flesh firmness, which is an important characteristic to improve breeding. The soluble solids content was high, above 14 ~Brix for 95% of the accessions with Tommy Atkins showing the lowest value, 12.5 ~Brix. A great diversity was found in the color of the epidermis ranging from green to red. The accessions Amrapali and Salitre presented a dark orange flesh color. The obtained data set, are the most comprehensive so far in Brazil, it allows choosing the best parents to develop new cultivars and will also contribute to the protection of mango cultivars in Brazil.

Genetic Diversity in the Semi-Arid Grown Cowpea(<i>Vigna unguiculata</i>L. Walp)Accessions Using Morphological and Molecular Characterization

Assessment of genetic diversity of the indigenous crop accessions is extremely important for breeders to identify potential parents in cross-breeding programs. Fourteen cowpea accessions collected from different parts of Sudan were used for characterization at morphological and molecular levels. The seeds of the accessions were sown in the field using a randomized complete block design with three replicates. Sixteen morphological descriptors (9 qualitative and 7 quantitative) and 20 Random Amplified Polymorphic DNA (RAPD) markers were used for characterization of the accessions. The results of morphological data revealed considerable variability within and between state’s accessions. Some morphological traits revealed similarity between accessions from different states. Among the 20 RAPD markers used, 18 were polymorphic. A total of 379 polymorphic patterns were generated;polymorphic information content (PIC) ranged from 0.63 to 0.98 with an average of 0.9. The number of fragment detected ranged from 2 for OPL-11 to 51 for OPY-2 with an average of 26.06/primer and 27.07/genotype. One to five (1 - 5) unique fragments of different sizes were detected for particular accessions, which may provide a valuable resource for breeding superior cowpea cultivars in Sudan and other semi-arid zones. Genetic similarity was ranged from 0.02 to 0.47 with an average of 0.25. Highest genetic similarity was between genotypes HSD-2966 and HSD-2967 and between genotypes HSD-5131 and HSD-5627 and the lowest was between HSD-5131 and HSD-5861 followed by that between HSD-2976 and HSD-29130 accessions. The study recommends the combination of morphological and molecular data for more efficient genetic diversity assessment and management.

Comparison of Proximate Composition and Nutritional Qualities of Fifty-Three Cashew Accessions from Burkina Faso

Cashew cultivation is growing in Burkina Faso, but nut production remains low. Identification of high-performance plant material with known varietal characteristics is essential for breeding. This study consisted of physical-chemical and nutritional characterization of almonds from a core selection of 53 cashew accessions from Burkina Faso. Proximate composition included contents in water, lipids, carbohydrates, proteins, ash, cellulose using standard methods. Major constituents were lipids with an average level of 50.71% ± 4.07%, followed by carbohydrates and proteins with average levels of 21.18% ± 3.81% and 20.62% ± 1.58%, respectively. Average water, ash and cellulose levels were 4.56% ± 0.39%, 2.87% ± 0.27% and 4.61% ± 2.52%, respectively. The analysis of variability within accessions, based on physical and chemical parameters, identified 3 groups that differ in lipids, carbohydrates, proteins, cellulose and energy value. The first group containing 17 accessions of fat-rich cashews, average protein levels and very high energy values is more interesting for tree improvement programs.

Biometric Analysis on Genetic Divergence between Parental and Regenerated Accessions in Tall Coconut Palms (Cocos nucifera L.) from International Genebank for Africa and the Indian Ocean

This study endeavour assesses agromorphological likeness between initial introductions and regenerated accessions at the International Coconut Genebank for Africa and the Indian Ocean (ICG-AIO) based in C?te d’Ivoire. Ten couples of parental (G0) and regenerated (G1) accessions of Tall coconut palms were analyzed using Principal Component Analysis (PCA) and Multiple Analysis of Variance (MANOVA) from 26 agromorphological characters. The main results showed a relative decrease in the expression of the phenotypical traits concerning the component of the fruit, height and vigor of the stem and yield of bunches and fruits after one regeneration cycle. But, a high proportion (69%) of studied characters from leaf, inflorescence and nut components showed likeness between G0 and G1 accessions. After one regeneration cycle, the controlled pollination method guarantees significant conservation of the expression of the majority of agromorphological traits. Consequently, regenerated accessions of Tall coconut palms can be used to pursue research and development programs in C?te d’Ivoire.

Natural variations and geographical distributions of seed carotenoids and chlorophylls in 1167 Chinese soybean accessions

Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids and chlorophylls and revealed their associations with other nutritional quality traits in a genetically diverse set of Chinese soybean accessions comprised of cultivars and landraces.Genotype,planting year,accession type,seed cotyledon color,and ecoregion of origin significantly influenced the accumulation of carotenoids and chlorophylls.The mean total carotenoid content was in the range of 8.15–14.72μg g–1 across the ecoregions.The total carotenoid content was 1.2-fold higher in the landraces than in the cultivars.Soybeans with green cotyledons had higher contents of carotenoids and chlorophylls than those with yellow cotyledons.Remarkably,lutein was the most abundant carotenoid in all the germplasms,ranging from 1.35–37.44μg g–1.Carotenoids and chlorophylls showed significant correlations with other quality traits,which will help to set breeding strategies for enhancing soybean carotenoids without affecting the other components.Collectively,our results demonstrate that carotenoids are adequately accumulated in soybean seeds,however,they are strongly influenced by genetic factors,accession type,and germplasm origin.We identified novel germplasms with the highest total carotenoid contents across the various ecoregions of China that could serve as the genetic materials for soybean carotenoid breeding programs,and thereby as the raw materials for food sectors,pharmaceuticals,and the cosmetic industry.

Biochemical Responses Associated with Resistance to Nilaparvata lugens (Stal) in Wild Rice Accessions

Brown planthopper(BPH),Nilaparvata lugens(Stal),is a destructive insect pest of rice.It damages the plants by sucking the plant sap from the phloem tissues and results in wilting of plants due to reduced chlorophyll and protein contents.Severely attacked plants do not bear any grains and cause'hopper bum*condition(Catindig et al,2009).Both nymphae and adults suck sap primarily at the base of the tillers,and therefore their presence goes undetected.BPH is also responsible for transmitting various viral diseases like grassy stunt,ragged stunt and wilted stunt(Win et al,2011).The blanket use of insecticides to control this pest has resulted in natural enemy death,environmental pollution,insecticide resistance and population resurgence.Therefore,there is dare need to develop alternative management strategy for this pest,and host plant resistance can be the effective,economical and chemical-free approach to control BPH.

Selection of Sesame Accessions(Sesamum indicum L.)in Thua Thien Hue Province,Vietnam

The main objective of this study was to select the best accessions for use as potential breeding sources in Thua Thien Hue province.A total of 16 accessions were used in this study,of which three accessions from Ho Chi Minh city in Vietnam,four accessions supplied by Japan,six accessions collected from China,two accessions provided by the United States and one MèVàng local accession(control)from Thua Thien Hue.The field experiment was conducted from August 2016 to November 2016 and laid out in a random complete block design(RCBD)for three replications at Huong Long ward,Hue city,Thua Thien Hue province.Each accession was observed 10 plants per replication.The size of each plot was 10 m2 and the spacing of 25 cm×10 cm was applied.The results showed that experiment accessions can grow under Thua Thien Hue conditions.Of those,the actual yield of VV12,VDM21,VH12,VDM50,VH01 and VDM45 were higher than the other accessions with 1.65,1.64,1.55,1.54,1.52 and 1.45 tons/ha,respectively.Oil content of these six accessions was above 50%.Therefore,VV12,VDM21,VH12,VDM50,VH01 and VDM45 can be used for breeding and cultivation under local condition.

Local Taxonomy and Diversity of Chadian Sorghum [<i>Sorghum bicolor</i>(L.) Moench] Accessions

The integration of local plant genetic resources into the breeding program is an asset for research. The objective of this study is to assess the diversity and analyze the management practices of cultivated sorghum. A questionnaire following a participatory approach was submitted to 675 producers in 45 villages. The cultivars collected were characterized using 9 qualitative descriptors. In total, 151 accessions and 191 names were inventoried. On average, 25.17 accessions per department and 3.36 accessions per village. Local taxonomy is based on many criteria expressed in different local languages. The most common method of naming is that to the word sorghum is added either the color of the grain, the precocity, or any element deemed relevant by the farmers. Significant variability in grain and panicle traits was observed within the collection, except the color of the endosperm. The rate of diversity loss is 11.52% and red grain sorghums are the most threatened with extinction. Five accessions groups are differentiated by the presence or absence of awns, the color of glumes, and amount of grain covered by glumes, grain plumpness, and form. Based on productivity, precocity, plant size, seed shape, and color, the farmers identified seven promising accessions. This potential will be preserved and developed in the sorghum varietal improvement program in Chad.

Agromophological Characterisation of Amaranth Accessions from Malawi

Five amaranth (Amaranthus spp.) accessions from central and southern region of Malawi were characterised at Lilongwe University of Agriculture and Natural Resources using agro-morphological traits. A total of thirteen descriptors, defined by Plant Genetic Resources Institute (IPGRI), were used to characterise the amaranth accessions under study. Field experiments were carried out for two seasons in August to November, 2018 and January to March, 2019. The experiments were laid out in a Randomised Complete Block Design (RCBD), which was replicated four times. The qualitative (plant growth habit, leaf colour, inflorescence colour, stem colour, inflorescence spininess, seed colour) and quantitative traits (plant height, stem girth, leaf length, leaf width, inflorescence length, days to 80% flowering, grain yield, leaf yield, and days to 80% maturity) evaluated were significant in defining the uniqueness of different amaranth accessions evaluated. Significant differences (P < 0.05) obtained from analysis of variance were observed in all the parameters studied. Correlation analysis was conducted using Genstat statistical package version 18 while cluster analysis was done using R statistical software. The agro-morphological characterisation results showed a wide range of variation for most of the qualitative characters. Wide variability was present in all the qualitative characters except for plant growth habit where all the accessions exhibited erect plant growth habit. These results point to high possibility of genetic diversity of amaranth accessions in Malawi, it could be exploited in future breeding purposes and deserving conservation.

Agro-Morphological Characterization of a Collection of Fonio [Digitaria exilis (Kippist.) Stapf.] Accessions from Burkina Faso

Considered as the oldest cereal, fonio (Digitaria exilis Stapf.) is grown in West Africa for its therapeutic virtues, its nutritional and organoleptic qualities. It plays an important socio-cultural and economic role for the populations of western Burkina Faso. However, very few studies on the genetic diversity of fonio have been carried out. This study aims to contribute to a better knowledge of the diversity of Digitaria exilis in Burkina Faso using agro-morphological descriptors. Thus, 60 accessions of fonio collected from western Burkina Faso were characterized using 21 agro-morphological characters according to an Alpha Latice design with three replications. The study showed morphological variability for most of the qualitative and quantitative characters studied. Principal component analysis (PCA) explained 56.07% of the variability. Hierarchical cluster analysis splits the accessions of the collection into four clusters using seven characters. These characters can constitute basic criteria for differentiating fonio accessions in Burkina Faso. The accessions of Group II have a long cycle and high production of grain, while the accessions of Group IV have a short cycle and low production of grain. The groups identified can serve as a starting point for fonio breeding in Burkina Faso.

Weed-Suppressing Effect and Mechanism of Allelopathic Rice Accessions

Two allelopathic rice accessions, PI312777 and Allelopathy1, significantly suppressedthe growth of associated weeds in the field. Moreover, their weed-suppressing effectswere correlated with the cultivation patterns. The weed-suppressing effects of throwingand transplanting were more effective than that of direct seeding. Furthermore, theamounts of allelochemicals (resorcinols, flavones and hydroxamic acids) produced andreleased from two allelopathic rice accessions were much higher than that from a non-allelopathic rice variety Hua-Jing-Xian1, and reached the maximum concentration at the6th leaf stage. Differences in the weed-suppressing effects of rice accessions appear toresult from the accessions producing and releasing different amounts of allelochemicalsin the field. Further research confirmed that in PI312777 plants, allelochemicals weresynthesized by the above-ground parts, and then secreted through the root tissues. Roottissues of PI312777 plants never produced the allelochemicals. Root exudates fromPI312777 could significantly inhibit the growth of E. crus-galli surrounding rice plantsin water culture. However, when activated carbon was added to the culture solution, whichcould absorb allelochemicals from root exudates, the growth of E. crus-galli was nolonger significantly inhibited. Weed-suppressing effects of rice accessions depended onallelopathy, cultivation patterns and other factors in rice fields, while allelopathywas one of important factors. Interestingly, the amounts of allelochemicals produced andreleased from allelopathic rice plants may be induced by the presence of E. crus-galli.This suggests that there is a possible chemical recognition between rice and E. crus-galli.

Agromorphological Characterization of Amaranth Accessions

A sound fundamental knowledge of the agro morphological characteristics of amaranth accessions is crucial for promoting their use in food. This review aims to assess the genetic diversity within the collection to understand the range of genetic variation. Thirty-two agromorphological parameters of Ten amaranth accessions were analyzed in Samanko conditions. Wide variability was present concerning leaf pigmentation (PigF), flower density index (IDF), seed color (CH), and Branching index (IR). Statistical analysis showed significant differences among accessions for morphological characters such as number of plants, leaf width, stem height, terminal inflorescence length of stem, axillary inflorescence length, 50% flowering and 1000 grain weight. It appears that the Axillary Inflorescence (LIA) and the Length of the Terminal Inflorescence are correlated (r = 0.82). Length of the inflorescence terminal of the stem (LITT) and the Length of the Terminal Basal Branches (LITBT) are associated (r = 0.75). Stem height presents a robust correlation (r = 0.447) with 50% flowering date. The length of the inflorescence Axillary was also highly correlated with the length of the inflorescence terminal of the stem (r = 0.904*). Ascending hierarchical classification revealed three distinct classes: C1: Madira 1, Madira 2, A2004, A2002;C2: TP5-sel, N’gourouma, Akeri, AC-NL;C3: AHTI, Akeri. “Akeri.” “TP5-sel,” and “N’gourouma” are associated with the weight of 1000 grains, the length of the terminal branches, and the shape of the terminal inflorescence. “Poly” and “AHTI” are quite similar and are associated with the parameters of the length of basal branches and length of a terminal inflorescence of the stem “Madira 1”;“Madira 2”, “A2004”, “A2002” on the correlation circle indicates that the height of the plants and the 50% flowering date. These results indicate a high possibility of genetic diversity among the amaranth accessions within the collection. The data can be exploited in future breeding programs to improve the species.

基于大数据的继电保护运维管理系统的设计与实现

在双碳背景下,促进清洁能源消纳与碳减排已成为电网发展的重要目标。提出了一种优化方法,考虑可再生能源不确定性与系统功率储备进行系统调度。在预测误差分析的基础上,提出了一种基于负荷损失概率的评估方法,以确定系统运行储备功率。将系统运营成本和二氧化碳排放量建模为优化目标。优化过程包括两个阶段,在第一阶段优化中利用混合整数线性规划方法进行确定性优化,生成具有规定功率储备要求的发电机组组合。在第二阶段优化中考虑预测不确定性,对运行计划进行调整,使用可控发电机来处理预测偏差。将不同方法下可用运行储备功率、成本和二氧化碳排放量在仿真中进行了对比。与传统大数据技术及智能电网的发展为继电保护系统历史数据进行深层次挖掘提供了支撑,以此为基础研究了基于大数据的继电保护运维管理系统。文章针对基于大数据的继电保护运维管理系统进行设计,详细阐述了系统架构、数据库设计、系统功能模块、系统实现。系统在原始数据预处理的基础上进行数据可视化,从统计分析和动态分析两个角度对保护设备进行评估,实现了设备失效数据的统计计算、设备缺陷关联性分析、运行水平评估以及设备状态检修功能。系统实现了继电保护设备运维全流程管理,最终服务于继电保护检修工作,能够为运行人员状态检修提供参考,对于减小维修的盲目性、提高检修工作效率具有参考价值。

Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures

Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject.

Telemedicine and public health–pearls and pitfalls

We hereby comment on the interesting systematic review by Grewal et al where they have provided an overall picture of the current status of available tele-health programs in the United States with emphasis on the Amazon Clinic.Their analysis is an appreciable effort in discovering the features available and features lacking in these tele-health programs.The concept of tele-health originated to curtail the need for physical attendance of patients at health clinics,and has been beneficial during the coronavirus disease 2019 pandemic.We implore that the pearls and pitfalls of these programs have to be understood by policymakers prior to forming a consensus regarding the availability,accessibility and affordability of these programs as methods of healthcare delivery.Unrestricted proliferation of tele-health programs in their current form may pose threats to patient and provider safety and medicolegal liability.However,patients and providers must work together to improve them to meet their expectations and enable them to provide the best care for the ailing public.

De novo-design of highly exposed Co−N−C single-atom catalyst for oxygen reduction reaction

The nitrogen-coordinated metal single-atom catalysts(M−N−C SACs)with an ultra-high metal loading synthetized by direct high-temperature pyrolysis have been widely reported.However,most of metal single atoms in these catalysts were buried in the carbon matrix,resulting in a low metal utilization and inaccessibility for adsorption of reactants during the catalytic process.Herein,we reported a facile synthesis based on the hard-soft acid-base(HSAB)theory to fabricate Co single-atom catalysts with highly exposed metal atoms ligated to the external pyridinic-N sites of a nitrogen-doped carbon support.Benefiting from the highly accessible Co active sites,the prepared Co−N−C SAC exhibited a superior oxygen reduction reactivity comparable to that of the commercial Pt/C catalyst,showing a high turnover frequency(TOF)of 0.93 e^(−)·s^(-1)·site^(-1)at 0.85 V vs.RHE,far exceeding those of some representative SACs with a ultra-high metal content.This work provides a rational strategy to design and prepare M−N−C single-atom catalysts featured with high site-accessibility and site-density.