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Marcin Nobis - One of the best experts on this subject based on the ideXlab platform.
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Hybridisation, introgression events and cryptic speciation in Stipa (Poaceae): A case study of the Stipa heptapotamica hybrid-complex
Perspectives in Plant Ecology Evolution and Systematics, 2019Co-Authors: Marcin Nobis, Katarzyna Krawczyk, Polina D. Gudkova, Justyna Żabicka, Evgenii Baiakhmetov, Jakub SawickiAbstract:Abstract Hybridisation, considered one of the major drivers of speciation in plants, commonly occurs among many genera of grasses, including the genus Stipa L. one of the largest in the family Poaceae in the Old World. In the course of research on Stipa, we studied S. richteriana, S. lessingiana, and their putative hybrid S. heptapotamica, all of which grow in south-eastern Kazakhstan. Stipa heptapotamica is treated as a local endemic, known only from the eastern part of the country. We used an integrative approach, combining morphological and molecular data, to validate the status of the hybrid taxon and present for the first time clear data documenting natural hybridisation in Stipa. The macro- and micromorphological analyses presented here show S. heptapotamica to be intermediate to its parental species in the characters studied; pollen analysis demonstrates low viability of pollen grains (below 50% compared to 94% and 87% in S. lessingiana and S. richteriana, respectively); molecular analyses based on inter simple sequence repeat markers (ISSR) and next-generation sequencing (NGS) data prove that S. heptapotamica originated strictly from hybridisation events involving S. richteriana and S. lessingiana. ISSR markers reveal possible introgression events between S. lessingiana and S. heptapotamica, whereas NGS data analyses confirm the maternal inheritance of a plastome from S. lessingiana in S. heptapotamica and support the finding of cryptic lineages within S. richteriana.
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plastid super barcodes as a tool for species discrimination in feather grasses poaceae Stipa
Scientific Reports, 2018Co-Authors: Katarzyna Krawczyk, Marcin Nobis, Kamil Myszczynski, Ewelina Klichowska, Jakub SawickiAbstract:Present study was designed to verify which or if any of plastome loci is a hotspot region for mutations and hence might be useful for molecular species identification in feather grasses. 21 newly sequenced complete plastid genomes representing 19 taxa from the genus of Stipa were analyzed in search of the most variable and the most discriminative loci within Stipa. The results showed that the problem with selecting a good barcode locus for feather grasses lies in the very low level of genetic diversity within its plastome. None of the single chloroplast loci is polymorphic enough to play a role of a barcode or a phylogenetic marker for Stipa. The biggest number of taxa was successfully identified by the analysis of 600 bp long DNA fragment comprising a part of rbcL gene, the complete rbcL-rpl23 spacer and a part of rpl23 gene. The effectiveness of multi-locus barcode composed of six best-performing loci for Stipa (ndhH, rpl23, ndhF-rpl32, rpl32-ccsA, psbK-psbI and petA-psbJ) didn’t reach 70% of analyzed taxa. The analysis of complete plastome sequences as a super-barcode for Stipa although much more effective, still didn’t allow for discrimination of all the analyzed taxa of feather grasses.
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Phylogenetic implications of nuclear rRNA IGS variation in Stipa L. (Poaceae).
Scientific Reports, 2017Co-Authors: Katarzyna Krawczyk, Marcin Nobis, Arkadiusz Nowak, Monika Szczecińska, Jakub SawickiAbstract:The article takes up the problem of deficiency of molecular marker, which could illustrate molecular variability as well as phylogenetic relation within the genus of Stipa L. (Poaceae). Researches made so far hadn’t delivered sufficient information about relationships between particular taxa from the genus of Stipa. In the present study, we analyzed variability and phylogenetic informativeness of nuclear ribosomal DNA in six species from the genus against five other species from Poaceae including a division of this region into functional elements and domains. Our results showed that the intergenic spacer region, and especially its part adjacent to 26 S nrDNA, is a molecular marker giving a real chance for a phylogeny reconstruction of Stipa. The region seems to be the most phylogenetically informative for Stipa from all the chloroplast and nuclear markers tested so far. Comparative analysis of nrDNA repeat units from Stipa to other representatives of Poaceae showed that their structure does not deviate from the general scheme. However, the rate of evolution within the inter-repeats in the IGS region is extremely high and therefore it predestines the region for phylogenetic analyses of Stipa at genus level or in shallower taxonomic scale.
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Stipa ×fallax (Poaceae: Pooideae: Stipeae), a new natural hybrid from Tajikistan, and a new combination in Stipa drobovii
Phytotaxa, 2017Co-Authors: Marcin Nobis, Arkadiusz Nowak, Agnieszka Nobis, Sylwia Nowak, Justyna Żabicka, Piotr ŻabickiAbstract:Stipa ×fallax nothosp. nov . (Poaceae), from western Pamir Alai Mts (Tajikistan), is described and illustrated. Field observation, numerical analyses of morphology, and pollen grain viability data show that it originated from hybridization between S. drobovii and S. macroglossa subsp. macroglossa , species representing sections Smirnovia and Stipa , respectively. Stipa ×fallax is morphologically close to S. ×alaica and S. ×hissarica , but is distinguished by its shortly pilose lower part of the awn and densely pubescent leaves. Characters distinguishing S. ×fallax from its parental species as well as similar hybrid taxa in section Smirnovia that also grow in Central Asia are presented. The micromorphology of lemmas and leaves of S . ×fallax and its parental species was examined by scanning electron microscopy. We also propose the new combination Stipa drobovii var. iskanderkulica (Tzvelev) M.Nobis & A.Nowak.
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Two new varieties in Stipa (Poaceae) from Central Asia
Acta Musei Silesiae: Scientiae Naturales, 2016Co-Authors: Marcin Nobis, Arkadiusz NowakAbstract:Abstract The paper presents descriptions of two new taxa, Stipa ×brevicallosa var. hissarensis and Stipa orientalis var. ladakhorum. Both of them differ from the nominal varieties in having densely pubescent (not glabrous or scabrous) leaves of vegetative shoots. First of the above mentioned taxa occurs in Tajikistan (Pamir Alai Mts) whereas the second in India (Western Himalayas). Images of type specimens of both taxa are provided.
Guangsheng Zhou - One of the best experts on this subject based on the ideXlab platform.
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a self photoprotection mechanism helps Stipa baicalensis adapt to future climate change
Scientific Reports, 2016Co-Authors: Xiliang Song, Guangsheng Zhou, Zhenzhu Xu, Xiaomin Lv, Yuhui WangAbstract:We examined the photosynthetic responses of Stipa baicalensis to relative long-term exposure (42 days) to the predicted elevated temperature and water availability changes to determine the mechanisms through which the plant would acclimate to future climate change. Two thermal regimes (ambient and +4 °C) and three irrigation levels (partial, normal and excess) were used in environmental control chambers. The gas exchange parameters, light response curves and A/Ci curves were determined. The elevated temperature and partial irrigation reduced the net photosynthetic rate due to a limitation in the photosynthetic capacity instead of the intercellular CO2 concentration. Partial irrigation decreased Rubisco activation and limited RuBP regeneration. The reduction in Vcmax increased with increasing temperature. Excess irrigation offset the negative effect of drought and led to a partial recovery of the photosynthetic capacity. Although its light use efficiency was restricted, the use of light and dark respiration by Stipa baicalensis was unchanged. We concluded that nonstomatal limitation was the primary reason for photosynthesis regulation in Stipa baicalensis under relative long-term climate change conditions. Although climate change caused reductions in the light use efficiency and photosynthetic rate, a self-photoprotection mechanism in Stipa baicalensis resulted in its high ability to maintain normal live activities.
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sensitive indicators of zonal Stipa species to changing temperature and precipitation in inner mongolia grassland china
Frontiers in Plant Science, 2016Co-Authors: Xiaomin Lv, Guangsheng Zhou, Yuhui Wang, Xiliang SongAbstract:Climate change has dramatically affected plant functional traits. However, knowledge related to sensitivity of different functional traits and sensitive indicator representing plant growth under hydrothermal change remains unclear. In this study, we analyzed the response of four zonal Stipa species (S. baicalensis, S. grandis, S. breviflora and S. bungeana) from Inner Mongolia grassland to changing temperature (control, increased 1.5°C, 2°C, 4°C and 6°C), precipitation (decreased 30% and 15%, control, increased 15% and 30%) and their combined effects via climate control chambers. The relative change of functional traits in the unit of temperature and precipitation change was regarded as sensitivity coefficient and sensitive indicators were examined by pathway analysis. We found that sensitivity of the four Stipa species to changing temperature and precipitation could be ranked as follows: S. bungeana > S. grandis > S. breviflora > S. baicalensis. In particular, changes in leaf area, specific leaf area and root/shoot ratio could account for 86% of the changes in plant biomass in the four Stipa species. Also these three measurements were more sensitive to hydrothermal changes than the others. These three functional indicators reflected the combination of plant production capacity (leaf area), adaptive strategy (root/shoot ratio), instantaneous environmental effects (specific leaf area) and cumulative environmental effects (leaf area and root/shoot ratio). Thus, leaf area, specific leaf area and root/shoot ratio were chosen as sensitive indicators in response to changing temperature and precipitation for the Stipa species. These results could provide the basis for predicting the influence of climate change on Inner Mongolia grassland based on the magnitude of changes in sensitive indicators.
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interactive effects of elevated co2 and precipitation change on leaf nitrogen of dominant Stipa l species
Ecology and Evolution, 2015Co-Authors: Guangsheng Zhou, Yanling Jiang, Hui Wang, Zhenzhu Xu, Jian SongAbstract:Nitrogen (N) serves as an important mineral element affecting plant productivity and nutritional quality. However, few studies have addressed the interactive effects of elevated CO2 and precipitation change on leaf N of dominant grassland genera such as Stipa L. This has restricted our understanding of the responses of grassland to climate change. We simulated the interactive effects of elevated CO2 concentration and varied precipitation on leaf N concentration (Nmass) of four Stipa species (Stipa baicalensis, Stipa bungeana, Stipa grandis, and Stipa breviflora; the most dominant species in arid and semiarid grassland) using open-top chambers (OTCs). The relationship between the Nmass of these four Stipa species and precipitation well fits a logarithmic function. The sensitivity of these four species to precipitation change was ranked as follows: S. bungeana > S. breviflora > S. baicalensis > S. grandis. The Nmass of S. bungeana was the most sensitive to precipitation change, while S. grandis was the least sensitive among these Stipa species. Elevated CO2 exacerbated the effect of precipitation on Nmass. Nmass decreased under elevated CO2 due to growth dilution and a direct negative effect on N assimilation. Elevated CO2 reduced Nmass only in a certain precipitation range for S. baicalensis (163–343 mm), S. bungeana (164–355 mm), S. grandis (148–286 mm), and S. breviflora (130–316 mm); severe drought or excessive rainfall would be expected to result in a reduced impact of elevated CO2. Elevated CO2 affected the Nmass of S. grandis only in a narrow precipitation range. The effect of elevated CO2 reached a maximum when the amount of precipitation was 253, 260, 217, and 222 mm for S. baicalensis, S. bungeana, S. grandis, and S. breviflora, respectively. The Nmass of S. grandis was the least sensitive to elevated CO2. The Nmass of S. breviflora was more sensitive to elevated CO2 under a drought condition compared with the other Stipa species.
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responses of three Stipa communities net primary productivity along northeast china transect to seasonal distribution of precipitation
Journal of Applied Ecology, 2005Co-Authors: Wenping Yuan, Guangsheng ZhouAbstract:: This paper analyzed the annual dynamics of the net primary productivity (NPP) of three Stipa communities along Northeast China Transect, and based on an integral regression model, discussed the responses of the NPP to the seasonal distribution of precipitation, aimed to reveal the effects of precipitation availability on plant NPP. The results indicated that the main factor restricting the annual dynamics of three Stipa communities NPP was the annual fluctuation of the monthly precipitation from November to next August. The precipitation from November to next April had a positive effect on the NPP, while the effect of that from May to July was decreased in different degrees. The seasonal distribution pattern of precipitation was quite similar for test Stipa communities, but S. grandis community had a higher utilization efficiency of precipitation than S. krylovii community, and S. baicalensis community had a much higher utilization efficiency of precipitation. Therefore, the seasonal distribution pattern of precipitation and its different effects on Stipa communities could be the main reasons inducing the zonal distribution of three test Stipa communities.
Arkadiusz Nowak - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetic implications of nuclear rRNA IGS variation in Stipa L. (Poaceae).
Scientific Reports, 2017Co-Authors: Katarzyna Krawczyk, Marcin Nobis, Arkadiusz Nowak, Monika Szczecińska, Jakub SawickiAbstract:The article takes up the problem of deficiency of molecular marker, which could illustrate molecular variability as well as phylogenetic relation within the genus of Stipa L. (Poaceae). Researches made so far hadn’t delivered sufficient information about relationships between particular taxa from the genus of Stipa. In the present study, we analyzed variability and phylogenetic informativeness of nuclear ribosomal DNA in six species from the genus against five other species from Poaceae including a division of this region into functional elements and domains. Our results showed that the intergenic spacer region, and especially its part adjacent to 26 S nrDNA, is a molecular marker giving a real chance for a phylogeny reconstruction of Stipa. The region seems to be the most phylogenetically informative for Stipa from all the chloroplast and nuclear markers tested so far. Comparative analysis of nrDNA repeat units from Stipa to other representatives of Poaceae showed that their structure does not deviate from the general scheme. However, the rate of evolution within the inter-repeats in the IGS region is extremely high and therefore it predestines the region for phylogenetic analyses of Stipa at genus level or in shallower taxonomic scale.
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Stipa ×fallax (Poaceae: Pooideae: Stipeae), a new natural hybrid from Tajikistan, and a new combination in Stipa drobovii
Phytotaxa, 2017Co-Authors: Marcin Nobis, Arkadiusz Nowak, Agnieszka Nobis, Sylwia Nowak, Justyna Żabicka, Piotr ŻabickiAbstract:Stipa ×fallax nothosp. nov . (Poaceae), from western Pamir Alai Mts (Tajikistan), is described and illustrated. Field observation, numerical analyses of morphology, and pollen grain viability data show that it originated from hybridization between S. drobovii and S. macroglossa subsp. macroglossa , species representing sections Smirnovia and Stipa , respectively. Stipa ×fallax is morphologically close to S. ×alaica and S. ×hissarica , but is distinguished by its shortly pilose lower part of the awn and densely pubescent leaves. Characters distinguishing S. ×fallax from its parental species as well as similar hybrid taxa in section Smirnovia that also grow in Central Asia are presented. The micromorphology of lemmas and leaves of S . ×fallax and its parental species was examined by scanning electron microscopy. We also propose the new combination Stipa drobovii var. iskanderkulica (Tzvelev) M.Nobis & A.Nowak.
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Two new varieties in Stipa (Poaceae) from Central Asia
Acta Musei Silesiae: Scientiae Naturales, 2016Co-Authors: Marcin Nobis, Arkadiusz NowakAbstract:Abstract The paper presents descriptions of two new taxa, Stipa ×brevicallosa var. hissarensis and Stipa orientalis var. ladakhorum. Both of them differ from the nominal varieties in having densely pubescent (not glabrous or scabrous) leaves of vegetative shoots. First of the above mentioned taxa occurs in Tajikistan (Pamir Alai Mts) whereas the second in India (Western Himalayas). Images of type specimens of both taxa are provided.
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Multivariate morphometric analysis of the Stipa turkestanica group (Poaceae: Stipa sect. Stipa)
Plant Systematics and Evolution, 2016Co-Authors: Marcin Nobis, Arkadiusz Nowak, Polina D. Gudkova, Ewelina Klichowska, Kaja RolaAbstract:Based on numerical analyses of macromorphological characters (cluster analysis, principal coordinate analysis and principal component analysis), scanning electron microscopy observation of lemma and lamina micromorphology, as well as field observations, five taxa belonging to the Stipa turkestanica group have been recognized in the mountain area of Central Asia. They are S. turkestanica subsp. turkestanica , S. turkestanica subsp. trichoides , S. macroglossa subsp. macroglossa , S. macroglossa subsp. kazachstanica and S. kirghisorum . As a result of this study, we propose one new combination, S. macroglossa var. pubescens , and designate lectotypes for S. turkestanica subsp. trichoides and S. macroglossa var. pubescens , and an epitype for S. kirghisorum . Illustrations of micromorphological structures of the lemma, patterns of leaf hairiness and an identification key are provided. A taxonomic synopsis including information on nomenclatural types, synonyms, descriptions of the taxa, and, as supplementary information, a list of the specimens examined is also presented.
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A new synonym and a new combination in Stipa aliena Keng (Poaceae: Stipa sect. Regelia )
Phytotaxa, 2015Co-Authors: Marcin Nobis, Arkadiusz Nowak, Polina D. GudkovaAbstract:Stipa section Regelia comprises three species occurring in mountainous areas of Central Asia. One of them, S. smithii , was described by Martinovský in 1970, but the taxon has been overlooked in later taxonomical studies. The species was described with two varieties, var. smithii and var. macrocarpa . As a result of our taxonomical studies, we find the typical variety of the taxon to be conspecific with Stipa aliena , and propose that the second one be recognized as Stipa aliena var. macrocarpa comb. nov. Remarks on species belonging to section Regelia and micromorphological patterns of their lemma morphologies are discussed. A key to species close to S. aliena is provided.
Jakub Sawicki - One of the best experts on this subject based on the ideXlab platform.
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Hybridisation, introgression events and cryptic speciation in Stipa (Poaceae): A case study of the Stipa heptapotamica hybrid-complex
Perspectives in Plant Ecology Evolution and Systematics, 2019Co-Authors: Marcin Nobis, Katarzyna Krawczyk, Polina D. Gudkova, Justyna Żabicka, Evgenii Baiakhmetov, Jakub SawickiAbstract:Abstract Hybridisation, considered one of the major drivers of speciation in plants, commonly occurs among many genera of grasses, including the genus Stipa L. one of the largest in the family Poaceae in the Old World. In the course of research on Stipa, we studied S. richteriana, S. lessingiana, and their putative hybrid S. heptapotamica, all of which grow in south-eastern Kazakhstan. Stipa heptapotamica is treated as a local endemic, known only from the eastern part of the country. We used an integrative approach, combining morphological and molecular data, to validate the status of the hybrid taxon and present for the first time clear data documenting natural hybridisation in Stipa. The macro- and micromorphological analyses presented here show S. heptapotamica to be intermediate to its parental species in the characters studied; pollen analysis demonstrates low viability of pollen grains (below 50% compared to 94% and 87% in S. lessingiana and S. richteriana, respectively); molecular analyses based on inter simple sequence repeat markers (ISSR) and next-generation sequencing (NGS) data prove that S. heptapotamica originated strictly from hybridisation events involving S. richteriana and S. lessingiana. ISSR markers reveal possible introgression events between S. lessingiana and S. heptapotamica, whereas NGS data analyses confirm the maternal inheritance of a plastome from S. lessingiana in S. heptapotamica and support the finding of cryptic lineages within S. richteriana.
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plastid super barcodes as a tool for species discrimination in feather grasses poaceae Stipa
Scientific Reports, 2018Co-Authors: Katarzyna Krawczyk, Marcin Nobis, Kamil Myszczynski, Ewelina Klichowska, Jakub SawickiAbstract:Present study was designed to verify which or if any of plastome loci is a hotspot region for mutations and hence might be useful for molecular species identification in feather grasses. 21 newly sequenced complete plastid genomes representing 19 taxa from the genus of Stipa were analyzed in search of the most variable and the most discriminative loci within Stipa. The results showed that the problem with selecting a good barcode locus for feather grasses lies in the very low level of genetic diversity within its plastome. None of the single chloroplast loci is polymorphic enough to play a role of a barcode or a phylogenetic marker for Stipa. The biggest number of taxa was successfully identified by the analysis of 600 bp long DNA fragment comprising a part of rbcL gene, the complete rbcL-rpl23 spacer and a part of rpl23 gene. The effectiveness of multi-locus barcode composed of six best-performing loci for Stipa (ndhH, rpl23, ndhF-rpl32, rpl32-ccsA, psbK-psbI and petA-psbJ) didn’t reach 70% of analyzed taxa. The analysis of complete plastome sequences as a super-barcode for Stipa although much more effective, still didn’t allow for discrimination of all the analyzed taxa of feather grasses.
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Phylogenetic implications of nuclear rRNA IGS variation in Stipa L. (Poaceae).
Scientific Reports, 2017Co-Authors: Katarzyna Krawczyk, Marcin Nobis, Arkadiusz Nowak, Monika Szczecińska, Jakub SawickiAbstract:The article takes up the problem of deficiency of molecular marker, which could illustrate molecular variability as well as phylogenetic relation within the genus of Stipa L. (Poaceae). Researches made so far hadn’t delivered sufficient information about relationships between particular taxa from the genus of Stipa. In the present study, we analyzed variability and phylogenetic informativeness of nuclear ribosomal DNA in six species from the genus against five other species from Poaceae including a division of this region into functional elements and domains. Our results showed that the intergenic spacer region, and especially its part adjacent to 26 S nrDNA, is a molecular marker giving a real chance for a phylogeny reconstruction of Stipa. The region seems to be the most phylogenetically informative for Stipa from all the chloroplast and nuclear markers tested so far. Comparative analysis of nrDNA repeat units from Stipa to other representatives of Poaceae showed that their structure does not deviate from the general scheme. However, the rate of evolution within the inter-repeats in the IGS region is extremely high and therefore it predestines the region for phylogenetic analyses of Stipa at genus level or in shallower taxonomic scale.
Xiliang Song - One of the best experts on this subject based on the ideXlab platform.
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a self photoprotection mechanism helps Stipa baicalensis adapt to future climate change
Scientific Reports, 2016Co-Authors: Xiliang Song, Guangsheng Zhou, Zhenzhu Xu, Xiaomin Lv, Yuhui WangAbstract:We examined the photosynthetic responses of Stipa baicalensis to relative long-term exposure (42 days) to the predicted elevated temperature and water availability changes to determine the mechanisms through which the plant would acclimate to future climate change. Two thermal regimes (ambient and +4 °C) and three irrigation levels (partial, normal and excess) were used in environmental control chambers. The gas exchange parameters, light response curves and A/Ci curves were determined. The elevated temperature and partial irrigation reduced the net photosynthetic rate due to a limitation in the photosynthetic capacity instead of the intercellular CO2 concentration. Partial irrigation decreased Rubisco activation and limited RuBP regeneration. The reduction in Vcmax increased with increasing temperature. Excess irrigation offset the negative effect of drought and led to a partial recovery of the photosynthetic capacity. Although its light use efficiency was restricted, the use of light and dark respiration by Stipa baicalensis was unchanged. We concluded that nonstomatal limitation was the primary reason for photosynthesis regulation in Stipa baicalensis under relative long-term climate change conditions. Although climate change caused reductions in the light use efficiency and photosynthetic rate, a self-photoprotection mechanism in Stipa baicalensis resulted in its high ability to maintain normal live activities.
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sensitive indicators of zonal Stipa species to changing temperature and precipitation in inner mongolia grassland china
Frontiers in Plant Science, 2016Co-Authors: Xiaomin Lv, Guangsheng Zhou, Yuhui Wang, Xiliang SongAbstract:Climate change has dramatically affected plant functional traits. However, knowledge related to sensitivity of different functional traits and sensitive indicator representing plant growth under hydrothermal change remains unclear. In this study, we analyzed the response of four zonal Stipa species (S. baicalensis, S. grandis, S. breviflora and S. bungeana) from Inner Mongolia grassland to changing temperature (control, increased 1.5°C, 2°C, 4°C and 6°C), precipitation (decreased 30% and 15%, control, increased 15% and 30%) and their combined effects via climate control chambers. The relative change of functional traits in the unit of temperature and precipitation change was regarded as sensitivity coefficient and sensitive indicators were examined by pathway analysis. We found that sensitivity of the four Stipa species to changing temperature and precipitation could be ranked as follows: S. bungeana > S. grandis > S. breviflora > S. baicalensis. In particular, changes in leaf area, specific leaf area and root/shoot ratio could account for 86% of the changes in plant biomass in the four Stipa species. Also these three measurements were more sensitive to hydrothermal changes than the others. These three functional indicators reflected the combination of plant production capacity (leaf area), adaptive strategy (root/shoot ratio), instantaneous environmental effects (specific leaf area) and cumulative environmental effects (leaf area and root/shoot ratio). Thus, leaf area, specific leaf area and root/shoot ratio were chosen as sensitive indicators in response to changing temperature and precipitation for the Stipa species. These results could provide the basis for predicting the influence of climate change on Inner Mongolia grassland based on the magnitude of changes in sensitive indicators.
