scholarly journals Allelic Mutations in the Ripening-Inhibitor Locus Generate Extensive Variation in Tomato Ripening

2020 ◽  
Vol 183 (1) ◽  
pp. 80-95
Author(s):  
Yasuhiro Ito ◽  
Yasuyo Sekiyama ◽  
Hiroko Nakayama ◽  
Ayako Nishizawa-Yokoi ◽  
Masaki Endo ◽  
...  
Keyword(s):  
Extensive Variation ◽  
Ripening Inhibitor

scholarly journals NATURAL SELECTION WITH NUCLEAR AND CYTOPLASMIC TRANSMISSION. I. A DETERMINISTIC MODEL

Genetics ◽  
1984 ◽  
Vol 107 (4) ◽  
pp. 679-701
Author(s):  
Andrew G Clark
Keyword(s):  
Natural Selection ◽  
General Model ◽  
Deterministic Model ◽  
Genetic Locus ◽  
Nuclear Genes ◽  
Stability Of Equilibria ◽  
Extensive Variation ◽  
Existence And Stability

ABSTRACT A deterministic model allowing variation at a nuclear genetic locus in a population segregating two cytoplasmic types is formulated. Additive, multiplicative and symmetric viability matrices are analyzed for existence and stability of equilibria. The protectedness of polymorphisms in both nuclear genes and cytoplasmic types is also investigated in the general model. In no case is a complete polymorphism protected with this deterministic model. Results are discussed in light of the extensive variation in mtDNA that has recently been reported.

scholarly journals Female Genotypes Affect Sperm Displacement in Drosophila

Genetics ◽  
1998 ◽  
Vol 149 (3) ◽  
pp. 1487-1493 ◽  
Author(s):  
Andrew G Clark ◽  
David J Begun
Keyword(s):  
Drosophila Melanogaster ◽  
Genetic Variation ◽  
Natural Populations ◽  
Isogenic Line ◽  
Female Fitness ◽  
Sperm Displacement ◽  
Extensive Variation ◽  
Polymorphic Genes ◽  
Displacement Parameter ◽  
Competitive Success

Abstract Differential success of sperm is likely to be an important component of fitness. Extensive variation among male genotypes in competitive success of sperm in multiply mated females has been documented for Drosophila melanogaster. However, virtually all previous studies considered the female to be a passive vessel. Nevertheless, under certain conditions female fitness could be determined by her role in mediating use of sperm from multiple males. Here we ask whether females differ among genotypes in their tendency to exhibit last-male precedence. Competition of sperm from two tester male genotypes (bwD and B3-09, a third-chromosome isogenic line from Beltsville, MD) was quantified by doubly mating female lines that had been rendered homozygous for X, second, or third chromosomes isolated from natural populations. The composite sperm displacement parameter, P2′, was highly heterogeneous among lines, whether or not viability effects were compensated, implying the presence of polymorphic genes affecting access of sperm to eggs. Genetic variation of this type is completely neutral in the absence of pleiotropy or interaction between variation in the two sexes.

scholarly journals Somatic deficiency causes reproductive parasitism in a fungus

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Alexey A. Grum-Grzhimaylo ◽  
Eric Bastiaans ◽  
Joost van den Heuvel ◽  
Cristina Berenguer Millanes ◽  
Alfons J. M. Debets ◽  
...  
Keyword(s):  
Neurospora Crassa ◽  
Experimental Evolution ◽  
Evolutionary Dynamics ◽  
Genetic Load ◽  
Wild Type ◽  
Fusion Frequency ◽  
Somatic Fusion ◽  
Extensive Variation ◽  
Reproductive Parasitism ◽  
Multicellular Organisms

AbstractSome multicellular organisms can fuse because mergers potentially provide mutual benefits. However, experimental evolution in the fungus Neurospora crassa has demonstrated that free fusion of mycelia favours cheater lineages, but the mechanism and evolutionary dynamics of this exploitation are unknown. Here we show, paradoxically, that all convergently evolved cheater lineages have similar fusion deficiencies. These mutants are unable to initiate fusion but retain access to wild-type mycelia that fuse with them. This asymmetry reduces cheater-mutant contributions to somatic substrate-bound hyphal networks, but increases representation of their nuclei in the aerial reproductive hyphae. Cheaters only benefit when relatively rare and likely impose genetic load reminiscent of germline senescence. We show that the consequences of somatic fusion can be unequally distributed among fusion partners, with the passive non-fusing partner profiting more. We discuss how our findings may relate to the extensive variation in fusion frequency of fungi found in nature.

scholarly journals Light and ripening-regulated BBX protein-encoding genes in Solanum lycopersicum

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Bruno Silvestre Lira ◽  
Maria José Oliveira ◽  
Lumi Shiose ◽  
Raquel Tsu Ay Wu ◽  
Daniele Rosado ◽  
...  
Keyword(s):  
Tomato Fruit ◽  
Protein Family ◽  
Tomato Genome ◽  
Physiological Processes ◽  
Fruit Development And Ripening ◽  
Protein Encoding ◽  
Ripening Inhibitor ◽  
Encoding Genes ◽  
Signalling Cascade

Abstract Light controls several aspects of plant development through a complex signalling cascade. Several B-box domain containing proteins (BBX) were identified as regulators of Arabidopsis thaliana seedling photomorphogenesis. However, the knowledge about the role of this protein family in other physiological processes and species remains scarce. To fill this gap, here BBX protein encoding genes in tomato genome were characterised. The robust phylogeny obtained revealed how the domain diversity in this protein family evolved in Viridiplantae and allowed the precise identification of 31 tomato SlBBX proteins. The mRNA profiling in different organs revealed that SlBBX genes are regulated by light and their transcripts accumulation is directly affected by the chloroplast maturation status in both vegetative and fruit tissues. As tomato fruits develops, three SlBBXs were found to be upregulated in the early stages, controlled by the proper chloroplast differentiation and by the PHYTOCHROME (PHY)-dependent light perception. Upon ripening, other three SlBBXs were transcriptionally induced by RIPENING INHIBITOR master transcriptional factor, as well as by PHY-mediated signalling and proper plastid biogenesis. Altogether, the results obtained revealed a conserved role of SlBBX gene family in the light signalling cascade and identified putative members affecting tomato fruit development and ripening.

scholarly journals Survey of husbandry and health on UK commercial dairy goat farms

2019 ◽  
Vol 185 (9) ◽  
pp. 267-267 ◽  
Author(s):  
K. Anzuino ◽  
T. G. Knowles ◽  
M.R.F. Lee ◽  
R. Grogono-Thomas
Keyword(s):  
Body Condition ◽  
Fat Body ◽  
Postal Survey ◽  
Dairy Goat ◽  
Poor Growth ◽  
Extensive Variation ◽  
Goat Population ◽  
Optimal Value ◽  
The Uk ◽  
Published Research

Published research relevant to the UK dairy goat industry is scarce. Current practices and concerns within the UK dairy goat industry must be better understood if research is to have optimal value. A postal survey was conducted of the farmer membership of the Milking Goat Association as a first step in addressing gaps in knowledge. Questions were asked about husbandry practices, farmer observations of their goats and their priorities for further research. Seventy-three per cent of Milking Goat Association members responded, representing 38 per cent of commercial dairy goat farms and 53 per cent of the commercial dairy goat population in England and Wales. Findings were comprehensive and showed extensive variation in farm practices. Farmers reported pneumonia and scours (diarrhoea) as the most prevalent illnesses of their kids. Pneumonia, diarrhoea, failure to conceive and poor growth were the most prevalent observations of youngstock. Overly fat body condition, assisted kidding, failure to conceive and difficulty drying off were the most prevalent observations of adult milking goats. Farmers’ top priorities for further research were kid health (79.5 per cent of farmers), Johne’s disease (69.5 per cent of farmers), tuberculosis (59 per cent of farmers) and nutrition (47.7 per cent of farmers).

Evaluation of Fsub(1) hybrids incorporating the rin (ripening inhibitor) gene to improve the storage life and fruit quality of fresh market tomatoes (Lycopersicon esculentum Mill.)

1991 ◽  
Vol 31 (3) ◽  
pp. 407 ◽  
Author(s):  
VQ Nguyen ◽  
WJ Ashcroft ◽  
KH Jones ◽  
WB McGlasson
Keyword(s):  
New South ◽  
Storage Life ◽  
F1 Hybrids ◽  
Fresh Market ◽  
Heterozygous Condition ◽  
South Wales ◽  
Ripening Inhibitor ◽  
Tomato Cultivars ◽  
Ripe Stage

Four new F1 hybrids which incorporate the ripening inhibitor (rin) tomato mutation were compared with standard commercial tomato cultivars, including Flora-Dade, for the fresh market in New South Wales and Victoria. The rin gene, in the heterozygous condition, delayed the start of ripening by a few days, increased the interval between breaker and full ripe from 5 to 7 days compared with commercial cultivars, and increased the storage life of ripe fruits from 28 to 40 days at 20�C. There were no significant differences between the level of red colour developed by the rin hybrids and reference tomatoes; however, the rin hybrid fruits took 4 days longer to reach full red colour. The fruits of rin hybrid were as firm as the reference tomatoes when picked at breaker and stored at 20�C for 6 days. However, rin hybrid fruits were significantly (P<0.05) firmer than those of reference tomatoes when harvested at a full ripe stage. Of the 4 rin hybrids tested, HRAS 87-70, which showed the most promise, was released in February 1990 as 'Red Centre'.

Morphological variation of Dicranidion fragile and D. inaequalis in culture

1973 ◽  
Vol 51 (4) ◽  
pp. 795-799 ◽  
Author(s):  
Winifred Butterfield
Keyword(s):  
Cultural Studies ◽  
Morphological Variation ◽  
Basal Cells ◽  
Extensive Variation ◽  
Conidial Morphology

Cultural studies of single conidium isolates of strains of Dicranidion fragile Harkness, 1885, and Dicranidion inaequalis Tubaki and Yokoyama, 1971, revealed extensive variation in conidial morphology. Dicranidion inaequalis is placed in synonymy with D, fragile, because both produce stauroconidia with symmetrical and asymmetrical basal cells by single conidium isolates. The production of phragmoconidia as the variation or mutation of stauroconidia is discussed.

Sign in / Sign up

Export Citation Format

Share Document