Wild Accessions and Mutant Resources

Macadamia is a recently domesticated Australian native nut crop, and a large proportion of its wild germplasm is unexploited. Aiming to explore the existing diversity, 247 wild accessions from four species and inter-specific hybrids were phenotyped. A wide range of variation was found in growth and nut traits. Broad-sense heritability of traits were moderate (0.43–0.64), which suggested that both genetic and environmental factors are equally important for the variability of the traits. Correlations among the growth traits were significantly positive (0.49–0.76). There were significant positive correlations among the nut traits except for kernel recovery. The association between kernel recovery and shell thickness was highly significant and negative. Principal component analysis of the traits separated representative species groups. Accessions from Macadamia integrifolia Maiden and Betche, M. tetraphylla L.A.S. Johnson, and admixtures were clustered into one group and those of M. ternifolia F. Muell were separated into another group. In both M. integrifolia and M. tetraphylla groups, variation within site was greater than across sites, which suggested that the conservation strategies should concentrate on increased sampling within sites to capture wide genetic diversity. This study provides a background on the utilisation of wild germplasm as a genetic resource to be used in breeding programs and the direction for gene pool conservation.

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High-Throughput Chlorophyll and Carotenoid Profiling Reveals Positive Associations with Sugar and Apocarotenoid Volatile Content in Fruits of Tomato Varieties in Modern and Wild Accessions

Metabolites ◽

10.3390/metabo11060398 ◽

2021 ◽

Vol 11 (6) ◽

pp. 398

Author(s):

Yusuke Aono ◽

Yonathan Asikin ◽

Ning Wang ◽

Denise Tieman ◽

Harry Klee ◽

...

Keyword(s):

High Throughput ◽

Fruit Color ◽

Wild Relatives ◽

Aroma Compounds ◽

Soluble Solids ◽

Sugar Production ◽

Volatile Content ◽

Factors Influencing ◽

High Throughput Method ◽

Wild Accessions

Flavor and nutritional quality has been negatively impacted during the course of domestication and improvement of the cultivated tomato (Solanum lycopersicum). Recent emphasis on consumers has emphasized breeding strategies that focus on flavor-associated chemicals, including sugars, acids, and aroma compounds. Carotenoids indirectly affect flavor as precursors of aroma compounds, while chlorophylls contribute to sugar production through photosynthesis. However, the relationships between these pigments and flavor content are still unclear. In this study, we developed a simple and high-throughput method to quantify chlorophylls and carotenoids. This method was applied to over one hundred tomato varieties, including S. lycopersicum and its wild relatives (S. l. var. cerasiforme and S. pimpinellifolium), for quantification of these pigments in fruits. The results obtained by integrating data of the pigments, soluble solids, sugars, and aroma compounds indicate that (i) chlorophyll-abundant varieties have relatively higher sugar accumulations and (ii) prolycopene is associated with an abundance of linear carotenoid-derived aroma compounds in one of the orange-fruited varieties, “Dixie Golden Giant”. Our results suggest the importance of these pigments not only as components of fruit color but also as factors influencing flavor traits, such as sugars and aroma.

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Identification of Black Rot Resistance in a Wild Brassica Species and Its Potential Transferability to Cauliflower

Agronomy ◽

10.3390/agronomy10091400 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1400

Author(s):

Xiao-Guang Sheng ◽

Ferdinando Branca ◽

Zhen-Qing Zhao ◽

Jian-Sheng Wang ◽

Hui-Fang Yu ◽

...

Keyword(s):

Xanthomonas Campestris ◽

Resistance Breeding ◽

Brassica Species ◽

Gene Location ◽

F1 Hybrids ◽

Black Rot ◽

Resistant Parent ◽

F2 Population ◽

Related Wild Species ◽

Wild Accessions

Black rot is a destructive disease that affects B. oleracea crops, causing significant losses to growers throughout the world. The purpose of this study was to screen out new sources resistant to Xanthomonas campestris pv. campestris race 4 (Xcc4) in 26 cauliflower and six related wild species, and to assess the inheritance of resistance. The results indicate that most of the tested accessions were susceptible or had intermediate resistance, except the Boc4601 (a cauliflower stable inbred line) and PI435896, UNICT5168, and UNICT5169 (wild accessions). Among them, UNICT5169 (Brassica montana) and PI435896 (Brassica balearica) showed the strongest resistance to Xcc4, with significantly lower disease index (DI), area of the infected part (AIP) and proportion of the infected part to the total leaf area (PTL) values. UNICT 5169 was selected as an Xcc4-resistant parent because of its relatively good cross seed-setting rate with cauliflower cultivars. F1 hybrids were successfully produced between this wild resistant accession (UNICT 5169) and one susceptible cauliflower breeding line (Boc3202-4), indicating the potential transferability of this resistance to cauliflower. The results of the symptoms severity evaluation of the F2 population indicate that Xcc4 resistance in UNICT5169 is a quantitative trait, which guides future resistance gene location and black rot resistance breeding.

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First report of Fusarium proliferatum causing wilt and root rot disease on wild accessions of pigeonpea from India

Journal of Plant Pathology ◽

10.1007/s42161-021-00965-4 ◽

2021 ◽

Author(s):

Raj K. Mishra ◽

Monika Mishra ◽

Abhishek Bohra ◽

Satheesh Naik SJ ◽

Krishna Kumar

Keyword(s):

Root Rot ◽

Fusarium Proliferatum ◽

First Report ◽

Root Rot Disease ◽

Rot Disease ◽

Wild Accessions

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Selection of tomato lines and populations for fruit shape and resistance to tomato leafminer

Horticultura Brasileira ◽

10.1590/s0102-053620200202 ◽

2020 ◽

Vol 38 (2) ◽

pp. 117-125

Author(s):

Nathalia CV Resende ◽

Alex Antonio da Silva ◽

Wilson Roberto Maluf ◽

Juliano Tadeu V de Resende ◽

Andre Ricardo Zeist ◽

...

Keyword(s):

Fruit Shape ◽

Tuta Absoluta ◽

Fruit Morphology ◽

Santa Cruz ◽

Solanum Pennellii ◽

Market Segments ◽

Tomato Leafminer ◽

Wild Accessions ◽

Market Requirement ◽

Selection Of

ABSTRACT The market requirement regarding fruit type varies from region to region and it is necessary to produce cultivars with different patterns of fruit morphology. Therefore, the aim of this study was to select lines with resistance to tomato leafminer and different fruit shapes in order to meet the different market segments. Seventy-six lines and pre-selected populations were used for pest resistance together with four other susceptible controls (TOM-584, TOM-684, NC-123S, and Santa Clara) and two wild accessions (Solanum pennellii ‘LA 716’ and S. habrochaites var. glabratum ‘PI-127826’) considered resistant. The experiment consisted of tests of resistance to the tomato leafminer Tuta absoluta. The selection of lines was efficient, being obtained 33 lines or populations resistant to the tomato leafminer that comprise the market segments of the types of multilocular fruit, Santa Cruz, Saladette or Italian, as well as intermediate standards of fruits.

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The synaptic behaviour of the wild forms of Triticum turgidum and T. timopheevii

Genome ◽

10.1139/g01-031 ◽

2001 ◽

Vol 44 (4) ◽

pp. 517-522 ◽

Cited By ~ 1

Author(s):

M Martínez ◽

T Naranjo ◽

C Cuadrado ◽

C Romero

Keyword(s):

Synaptonemal Complex ◽

Triticum Turgidum ◽

Genetic System ◽

Wild Wheat ◽

Homologous Chromosomes ◽

Tetraploid Wheats ◽

Ring Bivalents ◽

In The Wild ◽

The Mean ◽

Wild Accessions

Different wild allopolyploid species of Triticeae show extensive bivalent formation at zygotene while a considerable number of multivalents is present in cultivated polyploid wheats. To study the chromosome behaviour at early meiotic stages in wild forms of tetraploid wheats Triticum turgidum and T. timopheevii (2n = 4x = 28) we have analysed the synaptic pattern in fully traced spread nuclei at mid- and late zygotene and at pachytene of wild accessions of these species. The mean number of synaptonemal complex (SC) bivalents at mid-zygotene ranged from 12.22 to 13.14 among the accessions studied indicating a strong restriction of synapsis initiation to homologous chromosomes. The mean of bivalents increased at pachytene because of the transformation of multivalents into bivalents. Ring bivalents observed at metaphase I support that SC bivalents were formed by homologous chromosomes. The average values of SC bivalents at mid-zygotene in the wild forms are much higher than the average values observed in the cultivated tetraploid wheats but similar to that of a mutant line of T. turgidum with a duplication that includes Ph1, the major homoeologous pairing suppressor locus. These results suggest that the efficiency of the mechanism operating in the homologous recognition for synapsis is higher in wild wheat populations than in cultivated varieties. Apparently, a relatively detrimental modification of the pairing regulating genetic system accompanied the domestication of the wild wheat forms.Key words: Ph1 locus, Triticum turgidum, Triticum timopheevii, synaptonemal complex, diploidisation.

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Gene banks for wild and cultivated sunflower genetic resources

OCL ◽

10.1051/ocl/2020004 ◽

2020 ◽

Vol 27 ◽

pp. 9 ◽

Cited By ~ 1

Author(s):

Sreten Terzić ◽

Marie-Claude Boniface ◽

Laura Marek ◽

Daniel Alvarez ◽

Karin Baumann ◽

...

Keyword(s):

North America ◽

Genetic Resources ◽

Helianthus Annuus ◽

Inbred Lines ◽

Wild Sunflower ◽

Gene Banks ◽

Breeding Programmes ◽

Wild Accessions ◽

Modern Breeding ◽

Local Research

Modern breeding of sunflower (Helianthus annuus L.), which started 100 years ago, increased the number and the diversity of cultivated forms. In addition, for more than 50 years, wild sunflower and other Helianthus species have been collected in North America where they all originated. Collections of both cultivated and wild forms are maintained in gene banks in many countries where sunflower is an important crop, with some specificity according to the availability of germplasm and to local research and breeding programmes. Cultivated material includes land races, open pollinated varieties, synthetics and inbred lines. The majority of wild accessions are ecotypes of wild Helianthus annuus, but also 52 other species of Helianthus and a few related genera. The activities of three gene banks, in USA, France and Serbia, are described in detail, supplemented by data from seven other countries. Past and future uses of the genetic resources for environmental adaptation and breeding are discussed in relation to genomic and improved phenotypic knowledge of the cultivated and wild accessions available in the gene banks.

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Greenhouse test for the resistance to root and stem rot of Hypericum perforatum L. accessions

Plant Protection Science ◽

10.17221/10547-pps ◽

2017 ◽

Vol 38 (SI 2 - 6th Conf EFPP 2002) ◽

pp. 533-535

Author(s):

A. Kačergius ◽

D. Radaitienė

Keyword(s):

Root Rot ◽

Hypericum Perforatum ◽

Fusarium Avenaceum ◽

Stem Rot ◽

Aromatic Plants ◽

Artificial Infection ◽

Medicinal And Aromatic Plants ◽

Field Collection ◽

Hypericum Perforatum L ◽

Wild Accessions

Root and stem rot caused by soil-borne agent Fusarium avenaceum is a major disease of wild Hypericum perforatum accessions in the field collection of Medicinal and Aromatic Plants (MAP) of the Institute of Botany in Lithuania. These wild accessions of H. perforatum are growing as an initial material for breeding. In 1998–2001 the monitoring of epidemiological situation of field collection of H. perforatum showed differences among accessions considering the resistance to root rot. High intensity of root rot was observed in the third–fourth years of cultivation. The most damaged plants (> 50%) were among the accessions 219, 379, 381, and cv. Zolotodolinskaja. Fungi of the Aspergillus, Cladosporium, Penicillium, Rhizoctonia, and Verticillium genera were associated with H. perforatum roots together with the rot agent Fusarium avenaceum. Seven accessions from Lithuania and cv. Zolotodolinskaja of H. perforatum were tested for the resistance to root rot under greenhouse conditions. Two accessions (219, 381) were highly susceptible to the disease, another two (218, 383) were less susceptible, others were free of the symptoms of root rot. Accessions and single plants, survived after artificial infection, have been selected for further investigations.

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A genome resource for green millet Setaria viridis enables discovery of agronomically valuable loci

Nature Biotechnology ◽

10.1038/s41587-020-0681-2 ◽

2020 ◽

Vol 38 (10) ◽

pp. 1203-1210 ◽

Cited By ~ 2

Author(s):

Sujan Mamidi ◽

Adam Healey ◽

Pu Huang ◽

Jane Grimwood ◽

Jerry Jenkins ◽

...

Keyword(s):

Complex Traits ◽

De Novo ◽

Foxtail Millet ◽

Wild Plant ◽

Leaf Angle ◽

Setaria Viridis ◽

Model Species ◽

Seed Shattering ◽

A Genome ◽

Wild Accessions

Abstract Wild and weedy relatives of domesticated crops harbor genetic variants that can advance agricultural biotechnology. Here we provide a genome resource for the wild plant green millet (Setaria viridis), a model species for studies of C4 grasses, and use the resource to probe domestication genes in the close crop relative foxtail millet (Setaria italica). We produced a platinum-quality genome assembly of S. viridis and de novo assemblies for 598 wild accessions and exploited these assemblies to identify loci underlying three traits: response to climate, a ‘loss of shattering’ trait that permits mechanical harvest and leaf angle, a predictor of yield in many grass crops. With CRISPR–Cas9 genome editing, we validated Less Shattering1 (SvLes1) as a gene whose product controls seed shattering. In S. italica, this gene was rendered nonfunctional by a retrotransposon insertion in the domesticated loss-of-shattering allele SiLes1-TE (transposable element). This resource will enhance the utility of S. viridis for dissection of complex traits and biotechnological improvement of panicoid crops.

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