scholarly journals Fusarium Wilt Management in Legume Crops

Agronomy ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1073 ◽  
Author(s):  
Ana Margarida Sampaio ◽  
Susana de Sousa Araújo ◽  
Diego Rubiales ◽  
Maria Carlota Vaz Patto
Keyword(s):  
Fusarium Wilt ◽  
Management Strategies ◽  
Precision Breeding ◽  
Pests And Diseases ◽  
Agronomic Practices ◽  
Resistant Varieties ◽  
Major Factors ◽  
High Degree ◽  
Animal Consumption

Legumes are among the most important crops worldwide for human and animal consumption. However, yield inconsistency due to susceptibility to pests and diseases strongly affects its production. Among diseases affecting legumes, Fusarium wilt caused by the soil-borne pathogen Fusarium oxysporum Schltdl. (Fo) is one of the major factors limiting production worldwide. This disease can cause total losses in highly infested fields of some legume species. To minimize yield losses, integrated disease management strategies combining different agronomic practices with the use of resistant varieties should be applied. Although often characterized by a high degree of host specificity, with formae speciales (ff. spp.) and races identified, some Fo ff. spp. can have a broader host range, infecting more than one species, requiring further investigation. In this review, we describe the state of the art on legume Fusarium wilt management achievements, highlighting different aspects such as the use of rhizosphere microbiota as biocontrol agents, crop rotation and the use of resistant varieties. The different methods of identification and characterization of resistance sources, mechanisms as well as the genetic basis of resistance or the development of molecular tools to support legume precision breeding for Fo resistance are discussed.

scholarly journals Characterization of the Spatiotemporal Attributes of Sclerotinia Flower Blight Epidemics in a Perennial Pyrethrum Pathosystem

Plant Disease ◽  
2010 ◽  
Vol 94 (11) ◽  
pp. 1305-1313 ◽  
Author(s):  
Sarah J. Pethybridge ◽  
Frank S. Hay ◽  
David H. Gent
Keyword(s):  
Binomial Distribution ◽  
Management Strategies ◽  
Spatial Association ◽  
Sampling Unit ◽  
Data Sets ◽  
Estimated Parameters ◽  
Unit Scale ◽  
The Individual ◽  
High Degree

Sclerotinia flower blight, caused by Sclerotinia sclerotiorum, causes substantial losses in Australian pyrethrum fields. The spatiotemporal characteristics of epidemics were characterized in five fields over 3 years. Log likelihood tests indicated that the β-binomial distribution fit better than the binomial distribution for 92% of the data sets. The index of dispersion, D, was significantly greater than 1 in 97% of the data sets. The estimated parameters of the slope and intercept terms of the binary power law were 1.631 (standard error [SE] = 0.059) and 0.678 (SE = 0.099), indicating a high degree of aggregation at the individual sampling unit scale. In 69% of the data sets, the magnitude of the first-order autocorrelation coefficient [Formula: see text], was significantly greater than 0. In 11 of the 12 epidemics, the monomolecular model provided the best fit, indicative of monocyclic processes. A significant spatial association between apothecia and incidence of Sclerotinia flower blight within the lag of one sampling unit was also quantified. This study suggests that S. sclerotiorum apothecia emergence was closely synchronized with flower development, and epidemics were dominated by localized sources of ascosporic inoculums. This research provides the basis for improved management strategies for Sclerotinia flower blight in pyrethrum.

Characterization of Elite Genotypes for Fusarium Wilt Resistance in Pigeonpea [Cajanus cajan (L.) Millspaugh]

2021 ◽  
Author(s):  
Charu Bisht ◽  
S.K. Verma ◽  
A.K. Gaur ◽  
C. Chauhan ◽  
Harsh Deep ◽  
...  
Keyword(s):  
Molecular Analysis ◽  
Fusarium Wilt ◽  
Susceptible Variety ◽  
Research Centre ◽  
Wilt Resistance ◽  
Resistant Varieties ◽  
Superior Genotype ◽  
Crop Research ◽  
Fusarium Wilt Resistance

Background: The development of Fusarium wilt resistant varieties is a major challenge in pigeonpea breeding and need to be addressed on priority basis. In this study, efforts had been made to characterize the elite pigeonpea genotypes for Fusarium wilt resistance at morphological and molecular level. Methods: The present study was undertaken during kharif season of year 2018-19 at NEB, Crop Research Centre, G.B.P.U.A and T, Pantnagar. The experimental materials for present study consisted of 15 elite pigeonpea genotypes and three commercially grown popular varieties as checks. The molecular analysis was conducted during year 2019-20 and a susceptible variety BAHAR was used as check. The nine yield based indices were used for morphological analysis. The molecular analysis was carried out by using five already reported Fusarium wilt linked SSR markers. Result: The results revealed that the marker ASSR 363, ASSR 366, ASSR 1, ASSR 23 and ASSR 148 were highly effective in differentiating the resistant and susceptible genotypes of pigeonpea for wilt disease. On the basis of morphological and molecular studies, it was concluded that the genotype PA 626 was the most superior genotype as it not only yielded higher than all the three checks but also shown resistance against wilt at both phenotypic and genotypic level.

Characterization of RF Sputtered ZnO Piezoelectric Films Using Transmission Electron Microscope

1975 ◽  
Vol 33 ◽  
pp. 86-87
Author(s):  
Kemining W. Yeh ◽  
Richard S. Muller ◽  
Wei-Kuo Wu ◽  
Jack Washburn
Keyword(s):  
Integrated Circuit ◽  
Acoustic Waves ◽  
New Technology ◽  
Surface Acoustic Waves ◽  
Electromechanical Properties ◽  
Leading Role ◽  
Saw Devices ◽  
Transmission Electron ◽  
High Degree

Considerable and continuing interest has been shown in the thin film transducer fabrication for surface acoustic waves (SAW) in the past few years. Due to the high degree of miniaturization, compatibility with silicon integrated circuit technology, simplicity and ease of design, this new technology has played an important role in the design of new devices for communications and signal processing. Among the commonly used piezoelectric thin films, ZnO generally yields superior electromechanical properties and is expected to play a leading role in the development of SAW devices.

Identification of novel haplotype of a cyst nematode resistance gene, GmSNAP18 in soybean [Glycine max (L.) Merr.]

2020 ◽  
Vol 80 (03) ◽  
Author(s):  
Ik-Young Choi ◽  
Prakash Basnet ◽  
Hana Yoo ◽  
Neha Samir Roy ◽  
Rahul Vasudeo Ramekar ◽  
...  
Keyword(s):  
Soybean Cyst Nematode ◽  
Gene Families ◽  
Nematode Resistance ◽  
Cyst Nematode ◽  
Soybean Breeding ◽  
Resistant Varieties ◽  
Soybean Genotypes ◽  
Glycine Max L ◽  
Scn Resistance

Soybean cyst nematode (SCN) is one of the most damaging pest of soybean. Discovery and characterization of the genes involved in SCN resistance are important in soybean breeding. Soluble NSF attachment protein (SNAP) genes are related to SCN resistance in soybean. SNAP genes include five gene families, and 2 haplotypes of exons 6 and 9 of SNAP18 are considered resistant to the SCN. In present study the haplotypes of GmSNAP18 were surveyed and chacterized in a total of 60 diverse soybean genotypes including Korean cultivars, landraces, and wild-types. The target region of exons 6 and 9 in GmSNAP18 region was amplified and sequenced to examine nucleotide variation. Characterization of 5 haplotypes identified in present study for the GmSNAP18 gene revealed two haplotypes as resistant, 1 as susceptible and two as novel. A total of twelve genotypes showed resistant haplotypes, and 45 cultivars were found susceptible. Interestingly, the two novel haplotypes were present in 3 soybean lines. The information provided here about the haplotypic variation of GmSNAP18 gene can be further explored for soybean breeding to develop resistant varieties.

scholarly journals Application of Nematode Community Analyses-Based Models towards Identifying Sustainable Soil Health Management Outcomes: A Review of the Concepts

Soil Systems ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 32
Author(s):  
Haddish Melakeberhan ◽  
Gregory Bonito ◽  
Alexandra N. Kravchenko
Keyword(s):  
Nutrient Cycling ◽  
Health Management ◽  
Management Strategies ◽  
Soil Health ◽  
Agricultural Practices ◽  
Nematode Community ◽  
Parasitic Nematodes ◽  
Worst Case ◽  
Pests And Diseases ◽  
Water Holding

Soil health connotes the balance of biological, physicochemical, nutritional, structural, and water-holding components necessary to sustain plant productivity. Despite a substantial knowledge base, achieving sustainable soil health remains a goal because it is difficult to simultaneously: (i) improve soil structure, physicochemistry, water-holding capacity, and nutrient cycling; (ii) suppress pests and diseases while increasing beneficial organisms; and (iii) improve biological functioning leading to improved biomass/crop yield. The objectives of this review are (a) to identify agricultural practices (APs) driving soil health degradations and barriers to developing sustainable soil health, and (b) to describe how the nematode community analyses-based soil food web (SFW) and fertilizer use efficiency (FUE) data visualization models can be used towards developing sustainable soil health. The SFW model considers changes in beneficial nematode population dynamics relative to food and reproduction (enrichment index, EI; y-axis) and resistance to disturbance (structure index, SI; x-axis) in order to identify best-to-worst case scenarios for nutrient cycling and agroecosystem suitability of AP-driven outcomes. The FUE model visualizes associations between beneficial and plant-parasitic nematodes (x-axis) and ecosystem services (e.g., yield or nutrients, y-axis). The x-y relationship identifies best-to-worst case scenarios of the outcomes for sustainability. Both models can serve as platforms towards developing integrated and sustainable soil health management strategies on a location-specific or a one-size-fits-all basis. Future improvements for increased implementation of these models are discussed.

scholarly journals New Insights on the Zeugodacus cucurbitae (Coquillett) Bacteriome

2021 ◽  
Vol 9 (3) ◽  
pp. 659
Author(s):  
Elias Asimakis ◽  
Panagiota Stathopoulou ◽  
Apostolis Sapounas ◽  
Kanjana Khaeso ◽  
Costas Batargias ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Bacterial Communities ◽  
High Throughput Sequencing ◽  
Mutual Exclusion ◽  
Bacterial Composition ◽  
Operational Taxonomic Units ◽  
Host Diet ◽  
Dominant Bacteria ◽  
High Degree

Various factors, including the insect host, diet, and surrounding ecosystem can shape the structure of the bacterial communities of insects. We have employed next generation, high-throughput sequencing of the 16S rRNA to characterize the bacteriome of wild Zeugodacus (Bactrocera) cucurbitae (Coquillett) flies from three regions of Bangladesh. The tested populations developed distinct bacterial communities with differences in bacterial composition, suggesting that geography has an impact on the fly bacteriome. The dominant bacteria belonged to the families Enterobacteriaceae, Dysgomonadaceae and Orbaceae, with the genera Dysgonomonas, Orbus and Citrobacter showing the highest relative abundance across populations. Network analysis indicated variable interactions between operational taxonomic units (OTUs), with cases of mutual exclusion and copresence. Certain bacterial genera with high relative abundance were also characterized by a high degree of interactions. Interestingly, genera with a low relative abundance like Shimwellia, Gilliamella, and Chishuiella were among those that showed abundant interactions, suggesting that they are also important components of the bacterial community. Such knowledge could help us identify ideal wild populations for domestication in the context of the sterile insect technique or similar biotechnological methods. Further characterization of this bacterial diversity with transcriptomic and metabolic approaches, could also reveal their specific role in Z. cucurbitae physiology.

scholarly journals Genomic Tackling of Human Satellite DNA: Breaking Barriers through Time

2021 ◽  
Vol 22 (9) ◽  
pp. 4707
Author(s):  
Mariana Lopes ◽  
Sandra Louzada ◽  
Margarida Gama-Carvalho ◽  
Raquel Chaves
Keyword(s):  
Human Genome ◽  
Satellite Dna ◽  
Repetitive Sequences ◽  
Nucleotide Composition ◽  
Genomic Component ◽  
Genomic Studies ◽  
Human Genomic ◽  
Definition Of ◽  
High Degree

(Peri)centromeric repetitive sequences and, more specifically, satellite DNA (satDNA) sequences, constitute a major human genomic component. SatDNA sequences can vary on a large number of features, including nucleotide composition, complexity, and abundance. Several satDNA families have been identified and characterized in the human genome through time, albeit at different speeds. Human satDNA families present a high degree of sub-variability, leading to the definition of various subfamilies with different organization and clustered localization. Evolution of satDNA analysis has enabled the progressive characterization of satDNA features. Despite recent advances in the sequencing of centromeric arrays, comprehensive genomic studies to assess their variability are still required to provide accurate and proportional representation of satDNA (peri)centromeric/acrocentric short arm sequences. Approaches combining multiple techniques have been successfully applied and seem to be the path to follow for generating integrated knowledge in the promising field of human satDNA biology.

Sign in / Sign up

Export Citation Format

Share Document