Mating-type genes control sexual reproduction, conidial germination and virulence in Cochliobolus lunatus

Cochliobolus lunatus (anamorph: Curvularia lunata) is a major pathogenic fungus that causes the Curvularia leaf spot of maize. ClMAT1-1-1 and ClMAT1-2-1, the C. lunatus orthologs of Cochliobolus heterostrophus ChMAT1-1-1 and ChMAT1-2-1, were investigated in the present study to uncover their functions in C. lunatus. Southern blot analysis showed that these mating-type MAT genes exist in the C. lunatus genome as a single copy. ClMAT1-1-1 and ClMAT1-2-1 were knocked out and complemented to generate ΔClmat1-1-1 and ΔClmat1-2-1, ΔClmat1-1-1-C and ΔClmat1-2-1-C, respectively. The mutant strains had defective sexual development and failed to produce pseudothecia. There were no significant differences in growth rate or conidia production between the mutant and wild-type strains. However, the aerial mycelia and mycelial dry weight of ΔClmat1-1-1 and ΔClmat1-2-1 were lower than that of wild type, suggesting that MAT genes affect asexual development. ClMAT genes were involved in the responses to cell wall integrity and osmotic adaptation. ΔClmat1-2-1 had a lower conidial germination rate than the wild-type strain CX-3. The virulence of ΔClmat1-2-1 and ΔClmat1-1-1 was also reduced compared to the wild type. Complementary strains could restore all the phenotypes.

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Altered mating-type identity in the fungus Podospora anserina leads to selfish nuclei, uniparental progeny, and haploid meiosis.

Genetics ◽

10.1093/genetics/140.2.493 ◽

1995 ◽

Vol 140 (2) ◽

pp. 493-503 ◽

Cited By ~ 2

Author(s):

D Zickler ◽

S Arnaise ◽

E Coppin ◽

R Debuchy ◽

M Picard

Keyword(s):

Mating Type ◽

Podospora Anserina ◽

Wild Type ◽

Selfish Behavior ◽

Developmental Patterns ◽

Filamentous Ascomycete ◽

Type Identity ◽

Mat Locus ◽

Mat Genes

Abstract In wild-type crosses of the filamentous ascomycete Podospora anserina, after fertilization, only nuclei of opposite mating type can form dikaryons that undergo karyogamy and meiosis, producing biparental progeny. To determine the role played by the mating type in these steps, the four mat genes were mutagenized in vitro and introduced into a strain deleted for its mat locus. Genetic and cytological analyses of these mutant strain, crossed to each other and to wild type, showed that mating-type information is required for recognition of nuclear identity during the early steps of sexual reproduction. In crosses with strain carrying a mating-type mutation, two unusual developmental patterns were observed: monokaryotic cells, resulting in haploid meiosis, and uniparental dikaryotic cells providing, after karyogamy and meiosis, a uniparental progeny. Altered mating-type identity leads to selfish behavior of the mutant nucleus: it migrates alone or paired, ignoring its wild-type partner in all mutant x wild-type crosses. This behavior is nucleus-autonomous because, in the same cytoplasm, the wild-type nuclei form only biparental dikaryons. In P. anserina, mat genes are thus required to ensure a biparental dikaryotic state but appear dispensable for later stages, such as meiosis and sporulation.

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Effect of NaCl on the development of the oil palm vascular wilt fungus, Fusarium oxysporum f. sp. elaeidis.

International Journal of Phytopathology ◽

10.33687/phytopath.008.01.2788 ◽

2019 ◽

Vol 8 (1) ◽

pp. 09-21

Author(s):

Jacques S. B. Dossa ◽

Michaël Pernaci ◽

Euloge C. Togbé ◽

Euloge K. Agbossou ◽

Bonaventure C. Ahohuendo

Keyword(s):

Fusarium Oxysporum ◽

Oil Palm ◽

Elaeis Guineensis ◽

Disease Incidence ◽

Pathogenic Fungus ◽

Germination Rate ◽

Dry Weight ◽

Vascular Wilt ◽

Daily Growth ◽

Sporulation Rate

Oil palm Elaeis guineensis Jacq. (Arecaceae) is one of the cash crops that mainly contributes to the gross domestic production of growing countries. This crop is grown worldwide throughout the humid intertropical belt. Its production in Africa is mainly threatened by the telluric fungus Fusarium oxysporum f. sp. elaeidis, causal agent of the oil palm vascular wilt. It has been reported that some environmental factors, such as soil and air salinity, may determine the survival, development and severity of phytopathogenic agents including Fusarium. The purpose of this study was to evaluate the effect of NaCl on growth, reproduction and pathogenic traits of this fungus by measuring mycelium daily growth, mycelium dry weight, sporulation rate, germination rate and number of infectious spores under four NaCl concentrations (0 g.L-1, 2.5 g.L-1, 5 g.L-1 ,10 g.L-1) of culture medium (MM solid medium and Armstrong liquid medium). The results indicated that NaCl reduced the radial daily growth and mycelium dry weight. In addition, the NaCl reduced significantly the sporulation rate and number of infectious spores while increasing the germination rate. Overall, these results indicated the negative NaCl effect on the development and the fitness of this pathogenic fungus. Thus, NaCl inputs appeared to be a potential solution for managing Fusarium oxysporum f. sp. elaeidis in the field, if a good balance between a decrease of disease incidence and yield loss is reached.

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Co-expression of the Mating-Type Genes Involved in Internuclear Recognition Is Lethal in Podospora anserina

Genetics ◽

10.1093/genetics/155.2.657 ◽

2000 ◽

Vol 155 (2) ◽

pp. 657-669 ◽

Cited By ~ 3

Author(s):

Evelyne Coppin ◽

Robert Debuchy

Keyword(s):

Mating Type ◽

Transcriptional Control ◽

Wild Type Strain ◽

Podospora Anserina ◽

Wild Type ◽

Initial Development ◽

Genes Encoding ◽

In The Wild ◽

Mating Type Genes ◽

Mat Genes

Abstract In the heterothallic filamentous fungus Podospora anserina, four mating-type genes encoding transcriptional factors have been characterized: FPR1 in the mat+ sequence and FMR1, SMR1, and SMR2 in the alternative mat− sequence. Fertilization is controlled by FPR1 and FMR1. After fertilization, male and female nuclei, which have divided in the same cell, form mat+/mat− pairs during migration into the ascogenous hyphae. Previous data indicate that the formation of mat+/mat− pairs is controlled by FPR1, FMR1, and SMR2. SMR1 was postulated to be necessary for initial development of ascogenous hyphae. In this study, we investigated the transcriptional control of the mat genes by seeking mat transcripts during the vegetative and sexual phase and fusing their promoter to a reporter gene. The data indicate that FMR1 and FPR1 are expressed in both mycelia and perithecia, whereas SMR1 and SMR2 are transcribed in perithecia. Increased or induced vegetative expression of the four mat genes has no effect when the recombined gene is solely in the wild-type strain. However, the combination of resident FPR1 with deregulated SMR2 and overexpressed FMR1 in the same nucleus is lethal. This lethality is suppressed by the expression of SMR1, confirming that SMR1 operates downstream of the other mat genes.

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Salinity Tolerance of Black Gram Cultivars During Germination and Early Seedling Growth

Cercetari Agronomice in Moldova ◽

10.2478/cerce-2018-0025 ◽

2018 ◽

Vol 51 (3) ◽

pp. 51-68 ◽

Cited By ~ 1

Author(s):

M.K. Hasan ◽

M.S. Islam ◽

M.R. Islam ◽

H.N. Ismaan ◽

A. El Sabagh

Keyword(s):

Salt Stress ◽

Salinity Tolerance ◽

Seedling Growth ◽

Negative Impact ◽

Germination Rate ◽

Dry Weight ◽

Germination Percentage ◽

Shoot Length ◽

Sand Culture ◽

Black Gram

Abstract A laboratory experiment regarding germination and seedling growth test was conducted with three black gram genotypes tested under three salinity levels (0, 75 and 150 mM), for 10 days, in sand culture within small plastic pot, to investigate the germination and seedling growth characteristics. Different germination traits of all black gram genotypes, like germination percentage (GP), germination rate (GR), coefficient of velocity of germination (CVG) greatly reduced, as well as mean germination time (MGT) increased with increasing salt stress. At high salt stress, BARI Mash-3 provided the highest GP reduction (28.58%), while the lowest was recorded (15.79% to control) in BARI Mash-1. Salinity have the negative impact on shoot and root lengths, fresh and dry weights. The highest (50.32% to control) and lowest reduction (36.39%) of shoot length were recorded in BARI Mash-2 and BARI Mash-1, respectively, under 150 mM NaCl saline conditions. There were significant reduction of root lengths, root fresh and dry weight, shoot length, shoot fresh and dry weight in all genotypes under saline condition. The genotypes were arranged as BARI Mash-1 > BARI Mash-3 > BARI Mash-2, with respect to salinity tolerance.

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Effects of an Autoregulatory Senescence-inhibitor Gene Construct on Nicotiana alata Link and Otto.

HortScience ◽

10.21273/hortsci.33.3.519d ◽

1998 ◽

Vol 33 (3) ◽

pp. 519d-519 ◽

Cited By ~ 4

Author(s):

Kenneth R. Schroeder ◽

Dennis P. Stimart

Keyword(s):

Agrobacterium Tumefaciens ◽

Plant Height ◽

Dry Weight ◽

Nicotiana Alata ◽

Wild Type ◽

Gene Encoding ◽

Delayed Senescence ◽

Gene Construct ◽

Shoot Dry Weight ◽

Inhibitor System

Nicotiana alata Link and Otto. was transformed via Agrobacterium tumefaciens encoding a senescence-specific promoter SAG12 cloned from Arabidopsis thaliana fused to a Agrobacterium tumefaciens gene encoding isopentenyl transferase (IPT) that catalyzes cytokinin synthesis. This was considered an autoregulatory senescence-inhibitor system. In 1996, we reported delayed senescence of intact flowers by 2 to 6 d and delayed leaf senescence of transgenic vs. wild-type N. alata. Further evaluations in 1997 revealed several other interesting effects of the SAG12-IPT gene construct. Measurement of chlorophyll content of mature leaves showed higher levels of both chlorophyll a and b in transgenic material under normal fertilization and truncated fertilization regimes. At 4 to 5 months of age transgenic plants expressed differences in plant height, branching, and dry weight. Plant height was reduced by 3 to 13 cm; branch counts increased 2 to 3 fold; and shoot dry weight increased up to 11 g over wild-type N. alata. These observations indicate the system is not tightly autoregulated and may prove useful to the floriculture industry for producing compact and more floriferous plants.

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Overexpression of vesicle-associated membrane protein PttVAP27-17 as a tool to improve biomass production and the overall saccharification yields in Populus trees

Biotechnology for Biofuels ◽

10.1186/s13068-021-01895-0 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Madhavi Latha Gandla ◽

Niklas Mähler ◽

Sacha Escamez ◽

Tomas Skotare ◽

Ogonna Obudulu ◽

...

Keyword(s):

Membrane Protein ◽

Biomass Production ◽

Enzymatic Saccharification ◽

Dry Weight ◽

Populus Tremula ◽

Transgenic Trees ◽

Wild Type ◽

Glucose Yield ◽

Transgenic Lines ◽

Wild Type Control

Abstract Background Bioconversion of wood into bioproducts and biofuels is hindered by the recalcitrance of woody raw material to bioprocesses such as enzymatic saccharification. Targeted modification of the chemical composition of the feedstock can improve saccharification but this gain is often abrogated by concomitant reduction in tree growth. Results In this study, we report on transgenic hybrid aspen (Populus tremula × tremuloides) lines that showed potential to increase biomass production both in the greenhouse and after 5 years of growth in the field. The transgenic lines carried an overexpression construct for Populus tremula × tremuloides vesicle-associated membrane protein (VAMP)-associated protein PttVAP27-17 that was selected from a gene-mining program for novel regulators of wood formation. Analytical-scale enzymatic saccharification without any pretreatment revealed for all greenhouse-grown transgenic lines, compared to the wild type, a 20–44% increase in the glucose yield per dry weight after enzymatic saccharification, even though it was statistically significant only for one line. The glucose yield after enzymatic saccharification with a prior hydrothermal pretreatment step with sulfuric acid was not increased in the greenhouse-grown transgenic trees on a dry-weight basis, but increased by 26–50% when calculated on a whole biomass basis in comparison to the wild-type control. Tendencies to increased glucose yields by up to 24% were present on a whole tree biomass basis after acidic pretreatment and enzymatic saccharification also in the transgenic trees grown for 5 years on the field when compared to the wild-type control. Conclusions The results demonstrate the usefulness of gene-mining programs to identify novel genes with the potential to improve biofuel production in tree biotechnology programs. Furthermore, multi-omic analyses, including transcriptomic, proteomic and metabolomic analyses, performed here provide a toolbox for future studies on the function of VAP27 proteins in plants.

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Unbiased second-division segregation in Neurospora

Genetics Research ◽

10.1017/s0016672300011046 ◽

1967 ◽

Vol 10 (3) ◽

pp. 289-294 ◽

Cited By ~ 3

Author(s):

Adrian M. Srb ◽

Howard Jarolmen

Keyword(s):

Mating Type ◽

Wild Type ◽

Different Origin

Results of crosses of a large number of Neurosporas of different origin, including several distinct strains of N. sitophila, were utilized to re-examine the question of whether certain wild-type Neurosporas other than N. crassa show biases in the two types of second-division segregation. Segregations for alleles of the mating type and peak loci on a wide variety of genetic backgrounds gave little evidence for excess either of symmetrical or asymmetrical ‘post-reduction’ asci.

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ESCAPE FROM MATING-TYPE INCOMPATIBILITY IN BISEXUAL (A + a) NEUROSPORA HETEROKARYONS

Canadian Journal of Genetics and Cytology ◽

10.1139/g75-058 ◽

1975 ◽

Vol 17 (3) ◽

pp. 441-449 ◽

Cited By ~ 11

Author(s):

A. M. DeLange ◽

A. J. F. Griffiths

Keyword(s):

Mating Type ◽

Loss Of Function ◽

Wild Type ◽

Opposite Mating Type ◽

Type Locus ◽

Heterokaryon Incompatibility ◽

Recessive Mutant ◽

Type Rate ◽

Wild Type Rate ◽

Incompatibility Locus

In Neurospora crassa, strains of opposite mating type generally do not form stable heterokaryons because the mating type locus acts as a heterokaryon incompatibility locus. However, when one A and one a strain, having complementing auxotrophic mutants, are placed together on minimal medium, growth may occur, although the growth is generally slow. In this study, escape from such slow growth to that at a wild type or near-wild type rate was observed. The escaped cultures are stable heterokaryons, mostly having lost the mating type allele function from one component nucleus, so that the nuclear types are heterokaryon compatible. Either A or a mating type can be lost. This loss of function has been attributed to deletion since only one nuclear type could be recovered in all heterokaryons except one, but deletion spanning adjacent loci has been directly demonstrated in a minority of cases. Alternatively when one component strain is tol and the other tol+ (tol being a recessive mutant suppressing the heterokaryon incompatibility associated with mating type), escape may occur by the deletion or mutation of tol+, also resulting in heterokaryon compatibility. An induction mechanism for escape is speculated upon.

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Accelerating Seed Germination and Juvenile Growth of Sorghum (Sorghum bicolor L. Moench) to Manage Climate Variability through Hydro-Priming

Atmosphere ◽

10.3390/atmos12040419 ◽

2021 ◽

Vol 12 (4) ◽

pp. 419

Author(s):

Siaka Dembélé ◽

Robert B. Zougmoré ◽

Adama Coulibaly ◽

John P. A. Lamers ◽

Jonathan P. Tetteh

Keyword(s):

Seed Germination ◽

Climate Variability ◽

Germination Rate ◽

Dry Weight ◽

Seed Priming ◽

Seedling Development ◽

Hot Water ◽

Crop Failure ◽

Simple Method ◽

Early Season

Agriculture in Mali, a country in Sahelian West Africa, strongly depends on rainfall and concurrently has a low adaptive capacity, making it consequently one of the most vulnerable regions to climate change worldwide. Since early-season drought limits crop germination, and hence growth, ultimately yield during rain-fed depending on production is commonly experienced nowadays in Mali. Germination and establishment of key crops such as the staple sorghum could be improved by seed priming. The effects of hydro-priming with different water sources (e.g., distilled, tap, rain, river, well water) were evaluated respectively for three priming time durations in tepid e.g., at 25 °C (4, 8, and 12 h) and by hot water at 70 °C (in contrast to 10, 20, and 30 min.) in 2014 and 2015. Seed germination and seedling development of nine sorghum genotypes were monitored. Compared to non-primed seed treatments, hydro-priming significantly [p = 0.01] improved final germination percentage, germination rate index, total seedling length, root length, root vigor index, shoot length, and seedling dry weight. The priming with water from wells and rivers resulted in significant higher seed germination (85%) and seedling development, compared to the three other sources of water. Seed germination rate, uniformity, and speed were enhanced by hydro-priming also. It is argued that hydro-priming is a safe and simple method that effectively improve seed germination and seedling development of sorghum. If used in crop fields, the above most promising genotypes may contribute to managing early season drought and avoid failure of seed germination and crop failure in high climate variability contexts.

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Phytotoxicity of Chitosan and SiO2 Nanoparticles to Seed Germination of Wheat (Triticum aestivum L.) and Barley (Hordeum vulgare L.) Plants

Notulae Scientia Biologicae ◽

10.15835/nsb9210075 ◽

2017 ◽

Vol 9 (2) ◽

pp. 242-249 ◽

Cited By ~ 5

Author(s):

Faride BEHBOUDI ◽

Zeinalabedin TAHMASEBI SARVESTANI ◽

Mohamad Zaman KASSAEE ◽

Seyed Ali Mohamad MODARES SANAVI ◽

Ali SOROOSHZADEH

Keyword(s):

Germination Rate ◽

Dry Weight ◽

Sio2 Nanoparticles ◽

Triticum Aestivum L ◽

Germination Percentage ◽

Hordeum Vulgare L ◽

Randomized Design ◽

Direct Exposure ◽

Contrast Exposure ◽

Mean Germination Time

Plants such as wheat and barley that are strategically important crops need to be considered to develop a comprehensive toxicity profile for nanoparticles (NPs). The present study was aimed to investigate the effects of chitosan and SiO2 NPs on wheat and barley plants. Two factorial experiments (seeds priming and direct exposure) were performed based on a completely randomized design in four replications. Results showed that the seeds priming with the NPs had not significant effect on germination parameters such as Germination Percentage (GP), Germination Rate (GR), Germination Value (GV), Mean Germination Time (MGT), Pick Value (PV) and Mean Daily Germination (MDG). In contrast, exposure of the seeds to the NPs had significant effects on these parameters. In both experiments, treatments had significant effects on shoot, seedling, root length, fresh and dry weight, as well as vigor indexes as compared to the control. In most traits, the best concentration of NPs was 30 ppm, whereas applications of the NPs with 90 ppm displayed adverse effects on majority of the studied traits. According to these results, selectivity in applications of NPs with suitable concentration and method is essential for different plant species.

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