The Experts below are selected from a list of 23508 Experts worldwide ranked by ideXlab platform

Kingsley W Dixon - One of the best experts on this subject based on the ideXlab platform.

  • seed dormancy soil type and protective shelters influence Seedling Emergence at shark bay western australia insight into global dryland revegetation
    Ecological Management and Restoration, 2017
    Co-Authors: Charles Ellery Mayence, Peter J Carrick, Dale Van Beem, Eefje Broenland, Kingsley W Dixon
    Abstract:

    Summary Seedling Emergence is a major constraint on dryland revegetation success. In this study, we investigated Seedling Emergence of six framework shrub species as influenced by seed treatment, soil type and protective shelters using a large field trial in arid Western Australia. We observed the main effects of seed treatment and soil type to account for the majority of the variation in Emergence. For species that exhibit pronounced dormancy, we found Emergence of dormancy-alleviated or treated (T) seed to be significantly greater than dormant or untreated (UT) seed, with responses varying across species (e.g. 41 times greater for Acacia ligulata Benth., and 10 times greater for Stylobasium spathulatum Desf.). For shallowly or nondormant species like Senna glutinosa (DC) Randall, UT seed Emergence was slightly greater than for T seed. Compared to subsoil, topsoil was more receptive to infiltration (3.44 vs. 0.38 mm/min), and less prone to compaction (1.24 vs. 1.67 g/cm3) and crusting (0.6 vs. 1.3 kg/cm2); however, subsoil had greater moisture retention. Shelters failed to benefit soil moisture retention in either soil type, but enhanced Emergence for most species. This study provides insight into how various cost-effective treatments can be utilized to manipulate seed dormancy to optimize Seedling Emergence, the intrinsic value of topsoil as a superior growth medium and the benefit of novel, low-cost shelters for enhancing Seedling Emergence. In arid environments, sowing T seed in combination with UT seed increases the likelihood of capitalizing on inherently variable precipitation events.

  • Biogenic ethylene promotes Seedling Emergence from the sediment seed bank in an ephemeral tropical rock pool habitat
    Plant and Soil, 2014
    Co-Authors: Adam T. Cross, Gregory R. Cawthray, David J. Merritt, Shane R. Turner, Michael Renton, Kingsley W Dixon
    Abstract:

    Background and aims Ethylene has been increasingly implicated as a regulatory mechanism in plant germination, growth, and development, and is produced from the sediments of freshwater habitats. In this paper, we analyse the production and origin of ethylene from ephemeral freshwater rock pool sediments, and explore the role of ethylene in regulating Seedling Emergence from the seed bank. Methods The production of ethylene from rock pool sediments subjected to variable moisture content and antibiotic treatments was assessed through gas chromatography, and the role of ethylene in regulating Seedling Emergence was determined by Seedling Emergence assays and seed germination experiments. Results Biogenic ethylene production from rock pool sediments occurred rapidly (3–6 h) following inundation, with the majority of Seedling Emergence occurring between 36 and 72 h. Inoculation of sediments with streptomycin and amphotericin B resulted in significantly reduced ethylene production (up to 60 % and 84 % respectively), and completely inhibited Seedling Emergence. Additionally, the exposure of dormant seeds to ethylene resulted in significantly increased seed germination percentage in five out of six rock pool species. Conclusions Biogenic ethylene production may play an important role in regulating seed dormancy and the timing of Seedling Emergence from the sediment seed bank following inundation events in rock pools and other freshwater aquatic communities.

  • biogenic ethylene promotes Seedling Emergence from the sediment seed bank in an ephemeral tropical rock pool habitat
    Plant and Soil, 2014
    Co-Authors: Adam T. Cross, Gregory R. Cawthray, David J. Merritt, Shane R. Turner, Michael Renton, Kingsley W Dixon
    Abstract:

    Ethylene has been increasingly implicated as a regulatory mechanism in plant germination, growth, and development, and is produced from the sediments of freshwater habitats. In this paper, we analyse the production and origin of ethylene from ephemeral freshwater rock pool sediments, and explore the role of ethylene in regulating Seedling Emergence from the seed bank. The production of ethylene from rock pool sediments subjected to variable moisture content and antibiotic treatments was assessed through gas chromatography, and the role of ethylene in regulating Seedling Emergence was determined by Seedling Emergence assays and seed germination experiments. Biogenic ethylene production from rock pool sediments occurred rapidly (3–6 h) following inundation, with the majority of Seedling Emergence occurring between 36 and 72 h. Inoculation of sediments with streptomycin and amphotericin B resulted in significantly reduced ethylene production (up to 60 % and 84 % respectively), and completely inhibited Seedling Emergence. Additionally, the exposure of dormant seeds to ethylene resulted in significantly increased seed germination percentage in five out of six rock pool species. Biogenic ethylene production may play an important role in regulating seed dormancy and the timing of Seedling Emergence from the sediment seed bank following inundation events in rock pools and other freshwater aquatic communities.

Zhen-ying Huang - One of the best experts on this subject based on the ideXlab platform.

  • seed mucilage interacts with soil microbial community and physiochemical processes to affect Seedling Emergence on desert sand dunes
    Plant Cell and Environment, 2019
    Co-Authors: Shudong Zhang, Xuejun Yang, Carol C Baskin, Jerry M Baskin, Zhaoren Wang, Rong Liu, Zhen-ying Huang
    Abstract:

    Seedling Emergence is a critical stage in the establishment of desert plants. Soil microbes participate in plant growth and development, but information is lacking with regard to the role of microbes on Seedling Emergence. We applied the biocides (captan and streptomycin) to assess how seed mucilage interacts with soil microbial community and physiochemical processes to affect Seedling Emergence of Artemisia sphaerocephala on the desert sand dune. Fungal and bacterial community composition and diversity and fungal-bacterial interactions were changed by both captan and streptomycin. Mucilage increased soil enzyme activities and fungal-bacterial interactions. Highest Seedling Emergence occurred under streptomycin and mucilage treatment. Members of the phyla Firmicutes and Glomeromycota were the keystone species that improved A. sphaerocephala Seedling Emergence, by increasing resistance of young Seedlings to drought and pathogen. Seed mucilage directly improved Seedling Emergence and indirectly interacted with the soil microbial community through strengthening fungal-bacterial interactions and providing favourable environment for soil enzymes to affect Seedling Emergence. Our study provides a comprehensive understanding of the regulatory mechanisms by which soil microbial community and seed mucilage interactively promote successful establishment of populations of desert plants on the barren and stressful sand dune.

  • effects of amount and frequency of precipitation and sand burial on seed germination Seedling Emergence and survival of the dune grass leymus secalinus in semiarid china
    Plant and Soil, 2014
    Co-Authors: Yajuan Zhu, Ming Dong, Xuejun Yang, Carol C Baskin, Jerry M Baskin, Zhen-ying Huang
    Abstract:

    Aims Seed germination and Seedling Emergence are vulnerable to water stress in arid environments. When precipitation is low and unpredictable during the early growing season, seeds near the sand surface often suffer from hydration/dehydration during germination. We investigated the responses of Seedling Emergence and survival of a sand dune grass with high sand stabilization value to amount and frequency of precipitation and depth of burial in sand.

  • seed mucilage improves Seedling Emergence of a sand desert shrub
    PLOS ONE, 2012
    Co-Authors: Xuejun Yang, Carol C Baskin, Jerry M Baskin, Guangzheng Liu, Zhen-ying Huang
    Abstract:

    The success of Seedling establishment of desert plants is determined by Seedling Emergence response to an unpredictable precipitation regime. Sand burial is a crucial and frequent environmental stress that impacts Seedling establishment on sand dunes. However, little is known about the ecological role of seed mucilage in Seedling Emergence in arid sandy environments. We hypothesized that seed mucilage enhances Seedling Emergence in a low precipitation regime and under conditions of sand burial. In a greenhouse experiment, two types of Artemisia sphaerocephala achenes (intact and demucilaged) were exposed to different combinations of burial depth (0, 5, 10, 20, 40 and 60 mm) and irrigation regimes (low, medium and high, which simulated the precipitation amount and frequency in May, June and July in the natural habitat, respectively). Seedling Emergence increased with increasing irrigation. It was highest at 5 mm sand burial depth and ceased at burial depths greater than 20 mm in all irrigation regimes. Mucilage significantly enhanced Seedling Emergence at 0, 5 and 10 mm burial depths in low irrigation, at 0 and 5 mm burial depths in medium irrigation and at 0 and 10 mm burial depths in high irrigation. Seed mucilage also reduced Seedling mortality at the shallow sand burial depths. Moreover, mucilage significantly affected Seedling Emergence time and quiescence and dormancy percentages. Our findings suggest that seed mucilage plays an ecologically important role in successful Seedling establishment of A. sphaerocephala by improving Seedling Emergence and reducing Seedling mortality in stressful habitats of the sandy desert environment.

  • responses of caryopsis germination Seedling Emergence and development to sand water content of agropyron cristatum l gaertn and bromus inermis leyss
    Journal of Integrative Plant Biology, 2005
    Co-Authors: Hui-ling Yang, Ming Dong, Zhen-ying Huang, Xuanwei Zhu, Zhi-ping Cao
    Abstract:

    Abstract: Responses of caryopsis germination, Seedling Emergence, and development of Agropyron cristatum (L.) Gaertn. (Gramineae) and Bromus inermisLeyss. (Gramineae), two dominant perennial grasses in the Otindag Sandland of China, to different sand water content (SWC; 1%, 2%, 3%, 4%, 6%, 8%, 12%, 16%, and 20%) were studied comparatively. The results showed that the germination responses of the two grasses to SWC were similar (i.e. caryopses could not germinate when the SWC was below 3%; at SWC ranging from 3% to 12%, the higher the SWC, the higher the germination percentage; and at a SWC of 12%-20%, germination reached similarly high percentages). At a sand burial depth of 0.5 cm, the threshold of SWC for Seedling Emergence was 6% for A. cristatum and 8% for B. inermis; at 12%-20% SWC, the Seedling Emergence of both species reached similarly high percentages. The Seedling growth responses of these two species to SWC gradients were different. For A. cristatum, the biomass of Seedlings increased with SWC from 6% to 12%, and decreased with SWC from 12% to 20%. For B. inermis, the biomass of Seedlings always increased with SWC from 8% to 20%. The results also showed that the Seedlings of both species allocated more biomass to the roots with decreases in SWC. The SWC changes from April to October in natural microhabitats of both species suggested that the SWC may play an important role in caryopsis germination, Seedling Emergence, and the growth characteristics of the two grasses. The responses of caryopsis germination, Seedling Emergence, and the growth characteristics of these two species to SWC may determine their distribution patterns in the Otindag Sandland. (Managing editor: Ya-Qin HAN)

Jerry M Baskin - One of the best experts on this subject based on the ideXlab platform.

  • seed mucilage interacts with soil microbial community and physiochemical processes to affect Seedling Emergence on desert sand dunes
    Plant Cell and Environment, 2019
    Co-Authors: Shudong Zhang, Xuejun Yang, Carol C Baskin, Jerry M Baskin, Zhaoren Wang, Rong Liu, Zhen-ying Huang
    Abstract:

    Seedling Emergence is a critical stage in the establishment of desert plants. Soil microbes participate in plant growth and development, but information is lacking with regard to the role of microbes on Seedling Emergence. We applied the biocides (captan and streptomycin) to assess how seed mucilage interacts with soil microbial community and physiochemical processes to affect Seedling Emergence of Artemisia sphaerocephala on the desert sand dune. Fungal and bacterial community composition and diversity and fungal-bacterial interactions were changed by both captan and streptomycin. Mucilage increased soil enzyme activities and fungal-bacterial interactions. Highest Seedling Emergence occurred under streptomycin and mucilage treatment. Members of the phyla Firmicutes and Glomeromycota were the keystone species that improved A. sphaerocephala Seedling Emergence, by increasing resistance of young Seedlings to drought and pathogen. Seed mucilage directly improved Seedling Emergence and indirectly interacted with the soil microbial community through strengthening fungal-bacterial interactions and providing favourable environment for soil enzymes to affect Seedling Emergence. Our study provides a comprehensive understanding of the regulatory mechanisms by which soil microbial community and seed mucilage interactively promote successful establishment of populations of desert plants on the barren and stressful sand dune.

  • distribution of three congeneric shrub species along an aridity gradient is related to seed germination and Seedling Emergence
    Aob Plants, 2015
    Co-Authors: Liming Lai, Carol C Baskin, Jerry M Baskin, Yuan Tian, Yongji Wang, Xuechun Zhao, Lianhe Jiang, Yuanrun Zheng
    Abstract:

    Environmental tolerance of a species has been shown to correlate positively with its geographical range. On the Ordos Plateau, three Caragana species are distributed sequentially along the precipitation gradient. We hypothesized that this geographical distribution pattern is related to environmental tolerances of the three Caragana species during seed germination and Seedling Emergence stages. To test this hypothesis, we examined seed germin- ation under different temperature, light and water potentials, and monitored Seedling Emergence for seeds buried at eight sand depths and given different amounts of water. Seeds of C. korshinskii germinated to high percentages at 5:1 5 to 25 : 358 Ci n both light and darkness, while those ofC. intermedia and C. microphylla did so only at 15 : 25 and 25 : 35 8C, respectively. Nearly 30 % of the C. korshinskii seeds germinated at 21.4 MPa at 20 and 25 8C, while no seeds of the other two species did so. Under the same treatments, Seedling Emergence percentages of C. korshinskii were higher than those of the other two species. The rank order of tolerance to drought and sand burial of the three species is C. korshinskii . C. intermedia . C. microphylla. The amount of precipitation and sand burial depth appear to be the main selective forces responsible for the geographical distribution of these species.

  • effects of amount and frequency of precipitation and sand burial on seed germination Seedling Emergence and survival of the dune grass leymus secalinus in semiarid china
    Plant and Soil, 2014
    Co-Authors: Yajuan Zhu, Ming Dong, Xuejun Yang, Carol C Baskin, Jerry M Baskin, Zhen-ying Huang
    Abstract:

    Aims Seed germination and Seedling Emergence are vulnerable to water stress in arid environments. When precipitation is low and unpredictable during the early growing season, seeds near the sand surface often suffer from hydration/dehydration during germination. We investigated the responses of Seedling Emergence and survival of a sand dune grass with high sand stabilization value to amount and frequency of precipitation and depth of burial in sand.

  • seed mucilage improves Seedling Emergence of a sand desert shrub
    PLOS ONE, 2012
    Co-Authors: Xuejun Yang, Carol C Baskin, Jerry M Baskin, Guangzheng Liu, Zhen-ying Huang
    Abstract:

    The success of Seedling establishment of desert plants is determined by Seedling Emergence response to an unpredictable precipitation regime. Sand burial is a crucial and frequent environmental stress that impacts Seedling establishment on sand dunes. However, little is known about the ecological role of seed mucilage in Seedling Emergence in arid sandy environments. We hypothesized that seed mucilage enhances Seedling Emergence in a low precipitation regime and under conditions of sand burial. In a greenhouse experiment, two types of Artemisia sphaerocephala achenes (intact and demucilaged) were exposed to different combinations of burial depth (0, 5, 10, 20, 40 and 60 mm) and irrigation regimes (low, medium and high, which simulated the precipitation amount and frequency in May, June and July in the natural habitat, respectively). Seedling Emergence increased with increasing irrigation. It was highest at 5 mm sand burial depth and ceased at burial depths greater than 20 mm in all irrigation regimes. Mucilage significantly enhanced Seedling Emergence at 0, 5 and 10 mm burial depths in low irrigation, at 0 and 5 mm burial depths in medium irrigation and at 0 and 10 mm burial depths in high irrigation. Seed mucilage also reduced Seedling mortality at the shallow sand burial depths. Moreover, mucilage significantly affected Seedling Emergence time and quiescence and dormancy percentages. Our findings suggest that seed mucilage plays an ecologically important role in successful Seedling establishment of A. sphaerocephala by improving Seedling Emergence and reducing Seedling mortality in stressful habitats of the sandy desert environment.

Carol C Baskin - One of the best experts on this subject based on the ideXlab platform.

  • seed mucilage interacts with soil microbial community and physiochemical processes to affect Seedling Emergence on desert sand dunes
    Plant Cell and Environment, 2019
    Co-Authors: Shudong Zhang, Xuejun Yang, Carol C Baskin, Jerry M Baskin, Zhaoren Wang, Rong Liu, Zhen-ying Huang
    Abstract:

    Seedling Emergence is a critical stage in the establishment of desert plants. Soil microbes participate in plant growth and development, but information is lacking with regard to the role of microbes on Seedling Emergence. We applied the biocides (captan and streptomycin) to assess how seed mucilage interacts with soil microbial community and physiochemical processes to affect Seedling Emergence of Artemisia sphaerocephala on the desert sand dune. Fungal and bacterial community composition and diversity and fungal-bacterial interactions were changed by both captan and streptomycin. Mucilage increased soil enzyme activities and fungal-bacterial interactions. Highest Seedling Emergence occurred under streptomycin and mucilage treatment. Members of the phyla Firmicutes and Glomeromycota were the keystone species that improved A. sphaerocephala Seedling Emergence, by increasing resistance of young Seedlings to drought and pathogen. Seed mucilage directly improved Seedling Emergence and indirectly interacted with the soil microbial community through strengthening fungal-bacterial interactions and providing favourable environment for soil enzymes to affect Seedling Emergence. Our study provides a comprehensive understanding of the regulatory mechanisms by which soil microbial community and seed mucilage interactively promote successful establishment of populations of desert plants on the barren and stressful sand dune.

  • distribution of three congeneric shrub species along an aridity gradient is related to seed germination and Seedling Emergence
    Aob Plants, 2015
    Co-Authors: Liming Lai, Carol C Baskin, Jerry M Baskin, Yuan Tian, Yongji Wang, Xuechun Zhao, Lianhe Jiang, Yuanrun Zheng
    Abstract:

    Environmental tolerance of a species has been shown to correlate positively with its geographical range. On the Ordos Plateau, three Caragana species are distributed sequentially along the precipitation gradient. We hypothesized that this geographical distribution pattern is related to environmental tolerances of the three Caragana species during seed germination and Seedling Emergence stages. To test this hypothesis, we examined seed germin- ation under different temperature, light and water potentials, and monitored Seedling Emergence for seeds buried at eight sand depths and given different amounts of water. Seeds of C. korshinskii germinated to high percentages at 5:1 5 to 25 : 358 Ci n both light and darkness, while those ofC. intermedia and C. microphylla did so only at 15 : 25 and 25 : 35 8C, respectively. Nearly 30 % of the C. korshinskii seeds germinated at 21.4 MPa at 20 and 25 8C, while no seeds of the other two species did so. Under the same treatments, Seedling Emergence percentages of C. korshinskii were higher than those of the other two species. The rank order of tolerance to drought and sand burial of the three species is C. korshinskii . C. intermedia . C. microphylla. The amount of precipitation and sand burial depth appear to be the main selective forces responsible for the geographical distribution of these species.

  • effects of amount and frequency of precipitation and sand burial on seed germination Seedling Emergence and survival of the dune grass leymus secalinus in semiarid china
    Plant and Soil, 2014
    Co-Authors: Yajuan Zhu, Ming Dong, Xuejun Yang, Carol C Baskin, Jerry M Baskin, Zhen-ying Huang
    Abstract:

    Aims Seed germination and Seedling Emergence are vulnerable to water stress in arid environments. When precipitation is low and unpredictable during the early growing season, seeds near the sand surface often suffer from hydration/dehydration during germination. We investigated the responses of Seedling Emergence and survival of a sand dune grass with high sand stabilization value to amount and frequency of precipitation and depth of burial in sand.

  • seed mucilage improves Seedling Emergence of a sand desert shrub
    PLOS ONE, 2012
    Co-Authors: Xuejun Yang, Carol C Baskin, Jerry M Baskin, Guangzheng Liu, Zhen-ying Huang
    Abstract:

    The success of Seedling establishment of desert plants is determined by Seedling Emergence response to an unpredictable precipitation regime. Sand burial is a crucial and frequent environmental stress that impacts Seedling establishment on sand dunes. However, little is known about the ecological role of seed mucilage in Seedling Emergence in arid sandy environments. We hypothesized that seed mucilage enhances Seedling Emergence in a low precipitation regime and under conditions of sand burial. In a greenhouse experiment, two types of Artemisia sphaerocephala achenes (intact and demucilaged) were exposed to different combinations of burial depth (0, 5, 10, 20, 40 and 60 mm) and irrigation regimes (low, medium and high, which simulated the precipitation amount and frequency in May, June and July in the natural habitat, respectively). Seedling Emergence increased with increasing irrigation. It was highest at 5 mm sand burial depth and ceased at burial depths greater than 20 mm in all irrigation regimes. Mucilage significantly enhanced Seedling Emergence at 0, 5 and 10 mm burial depths in low irrigation, at 0 and 5 mm burial depths in medium irrigation and at 0 and 10 mm burial depths in high irrigation. Seed mucilage also reduced Seedling mortality at the shallow sand burial depths. Moreover, mucilage significantly affected Seedling Emergence time and quiescence and dormancy percentages. Our findings suggest that seed mucilage plays an ecologically important role in successful Seedling establishment of A. sphaerocephala by improving Seedling Emergence and reducing Seedling mortality in stressful habitats of the sandy desert environment.

James R Mahan - One of the best experts on this subject based on the ideXlab platform.

  • thermal dependence of malate synthase activity and its relationship to the thermal dependence of Seedling Emergence
    Journal of Agricultural and Food Chemistry, 2000
    Co-Authors: James R Mahan
    Abstract:

    Cotton yields are often reduced by low temperatures at early planting dates. Improved Seedling metabolism at low temperatures may enhance Seedling performance. The glyoxylate cycle plays a role in the metabolism of stored lipids, and thus thermal limitations on the function of malate synthase (EC 4.1.3.2) may be involved in low-temperature limitations on Seedlings. The thermal dependencies of the apparent K(M) and maximal velocity for the malate synthases from cotton (Gossypium hirsutum L.) and sunflower (Helianthus annuus L.) were determined across a 15-45 degrees C thermal range and used to estimate the thermal dependence of reaction velocity. The thermal dependence of Seedling Emergence was monitored for both species. The thermal dependencies of predicted reaction velocity and the measured rates of Seedling Emergence are correlated (cotton r(2) = 0.9, sunflower r(2) = 0.76) and suggest that the thermal dependencies of enzymes predicted from basic kinetic parameters may be useful indicators of the thermal dependence of more complex whole-plant processes.