Agropyron Cristatum Research Articles

Influence of crested wheatgrass on soil water repellency in comparison to native grass mix and annual spring wheat cropping

Crested wheatgrass (CWG) [Agropyron cristatum (L.) Gaertn.] is a commonly introduced grass in the Canadian prairies, but concerns remain about its possible long-term effects on soil quality, and its influence on soil water repellency (SWR) has not been determined. The long-term (24 yr) effects of CWG on SWR in comparison to seeded native grasses and annual cropping were determined for a clay loam soil in southern Alberta, Canada by measuring SOC concentration and SWR using soil hydrophobicity (SH) and soil water repellency index (RI) methods. The cropping treatments were CWG, seeded native grass mix (NGM), continuous wheat, and wheat–fallow rotation, each with fertilized (nitrogen) and non-fertilized subplots, replicated four times. Mean SOC concentration, SH, and RI in samples of surface soil were similar (P > 0.05) for CWG and seeded NGM, and they did not support our hypothesis (seeded NGM > CWG). Mean SOC was significantly greater for seeded perennial grasses than annual crops by 1.7–2 times and SH by 2.1–2.5 times, which supported our hypothesis, but RI was similar among treatments. As expected, nitrogen fertilization significantly increased SOC concentrations, but the effects on SH and RI were undetectable. A strong positive correlation occurred between SOC concentration and SH (r = 0.92) but not for RI (r = 0.10). Our findings suggested that SWR was similar for CWG and seeded NGM. The SWR as measured using SH was greater for seeded perennial grasses than annual cropping but was similar using RI.

Grazing-induced legacy effects enhance plant adaption to drought by larger root allocation plasticity

Abstract Aims To explore whether grazing-induced legacy effects on plants could benefit plants adaptation to drought. Methods A water-controlled experiment was conducted in the greenhouse, which with Agropyron cristatum and Carex korshinskyi collected from free-grazing and enclosed plots on a typical grassland in Inner Mongolia. Important Findings We found that A. cristatum and C. korshinskyi collected from the free-grazing plot were less affected by drought in terms of ramet biomass, ramet number and total biomass than those collected from the enclosed plot. The enhanced adaptation to drought for plants collected from the free-grazing plot should partly be ascribed to the larger root biomass allocation plasticity under drought treatment. Our findings suggest that grazing management can be used to improve the adaptation of grassland plants to climate change.

The Elemental Compositionin Aboveground and Underground Organs of Some Agropyron Species Grown in Different Salt Concentrations

Salinity, which is more common in semi-arid and arid areas, is increasing every day with climate change, poor quality irrigation water, and soil structure. High salt concentration restricts plant production and causes productivity loss in agriculture. To sustain agriculture in saline soils, the determination of plant species resistant to salinity comes into prominence in areas with salinity problems. For this reason, the research was performed to determine the nutrients (i.e., Ca, Mg, P, S, B, Cu, Fe, Mn, and Zn) accumulating at aboveground and underground parts of the three different Agropyron species, namely Agropyron cristatum , A. desertorum and A . elongatum (Syn. Elymus elongatus) under different salt concentrations (i.e., control, 5, 10 and 15 EC dS m -1 NaCl ). A. cristatum , A. desertorum , and A . elongatum species, which are quality forage crops grown in drought and salinity conditions, were determined to Ca content 1.03%, 1.01%, and 1.49% respectively, and Mg content. 0.13%, 0.11% and 0.20% respectively. As salt concentrations increased, Ca, Mg, Cu, Fe, Mn, and Zn in the aboveground organ has increased compared to the control treatment but decreased in the underground organs. Ca and Mg content of the aboveground organs of A. elongatum grown at 10 EC dS m -1 NaCl increased by 204% and 98%, respectively, compared to the control. Fe content of the wheatgrass species in saline conditions was found quite high, and an average of 788 ppm of Fe was found in underground organs while this value was as 430 ppm in aboveground organs. The results showed that A. elongatum had more nutrient elements in both underground and aboveground parts of the crop by comparison to the other two Agropyron species under increased salinity levels.

Assessing climate change risks to the geographical distribution of grass species

ABSTRACT There is extensive evidence showing the impact of climate change on the biology and biogeography of species. Adopting drought-tolerant plants to conserve water is a potential adaptation to reduce the consequences of climate change. Accordingly, it was hypothesized that climate change would not affect potential distributions of drought-tolerant species. Here, this hypothesis was tested to model the potential distribution of three drought-resistant plant. Here, the potential distribution of Agropyron cristatum, Agropyron desertorum, and Festuca arundinacea was studied in Iran under current and future climate conditions, using 10 species distribution models. Sixty-two climate change scenarios (19 global climate models (GCMs) under four Representative Concentration Pathways (RCPs)) were used to model the potential distribution of the three plants in Iran in the future. The three species have different responses to predicted climate change due to species-environment interactions, species morphological and physiological advancement. The three species showed different responses to predicted climate change due to species-environment interactions. Festuca arundinacea and Agropyron cristatum will, respectively, experience the most and least severe decline in suitable habitats in the next 50 years. This result is because decreased annual precipitation caused an increase in habitat suitability for A. cristatum, while the same variable had the opposite effect for A. desertorum and F. arundinacea. On the other hand, F. arundinacea grows on moist soils that decreased annual precipitation caused a decrease in habitat suitability. Also, our results have clearly shown that plant species drought-stress tolerant are not immune to climate change and their current distributions undergo significant changes as a result of the changing of climate.

Trace metals accumulation in the eco-system water – soil – vegetation (Agropyron cristatum) – common voles (Microtus arvalis) – parasites (Hymenolepis diminuta) in Radnevo region, Bulgaria

BackgroundCoal and coal processing industries provoke trace metal pollution, which has a negative effect on the water – soil – vegetation – small mammals eco-system, constituting part of the food chain and exerting a serious impact on human health. ObjectivesAssessment of the environmental impact of Maritza iztok coal complex, situated east of Radnevo town, Bulgaria, by tracking the dynamics and accumulation of trace metals in the eco-system water – soil – vegetation – common voles – parasites. MethodsSamples from surface waters, their nearby uncultivated soils, meadow uncultivated vegetation (Agropyron cristatum) and field common voles (Microtus arvalis) were collected. In situ measurements and laboratory extraction procedures and analyses were performed. Accumulation and mobility indices were calculated. The distribution of dissolved Mn, Ni, Cu, Zn and Pb chemical species in water-soil extracts was calculated using a thermodynamic approach. Two thermodynamic models were applied – the classical ion-association model for calculating the inorganic trace metal species and the Stockholm Humic Model (SHM) accounting for the complexation reactions of trace metals with organic matter. Visual Minteq computer program, Version 3.1 was used. The relationship chemical species - bioaccumulation was discussed. ResultsPb and Mn, together with SO42− and PO43- were found to be the main pollutants of waters in the region. The soils studied exhibited low concentrations of trace metals, not exceeding the specified MACs. The content of Mn was the highest, followed by Zn, Pb, Cu and Ni. The highest phytoaccumulation coefficients in the studied uncultivated grass vegetation were calculated for Cu and Zn, being 1–2 orders of magnitude higher than those of Mn and Ni. The accumulation of trace metals was explained on the basis of ions mobility and chemical species distribution. In the case of the host-parasite system Microtus alvaris - Hymenolepis diminuta, Zn displays the highest accumulation coefficient, followed by those of Cu and Pb. The parasite showed a higher bioaccumulation compared to infected common voles, with the highest bioaccumulation found for Ni. ConclusionsThe bioaccumulation of trace metals depends on their mobility, concentration and chemical forms in water-soil solutions. Metal-organic species stimulate the phytoaccumulation of trace metals while inorganic ones suppress it. The sequence of trace metals bioaccumulation in common voles is analogous to that of soil contamination. The parasite exhibited higher bioaccumulation levels compared to infected common voles.

Effect of simulated grazing on sediment trapping by single plants: A wind-tunnel experiment with two grassland species in Mongolia

Vegetative cover suppresses dust storms in arid regions. Rearing livestock is a major industry in arid regions, and although livestock consume grass, the effect of their grazing on the ability of grass to trap sediments is not well understood. This study quantified the effect of plant clipping, a mimic of animal grazing, on sediment trapping by single plants in a wind-tunnel experiment. The study focused on two grass species, Stipa krylovii and Agropyron cristatum, which are native to the Mongolian steppe and are highly palatable for livestock. The two species were grown to a height of approximately 30 cm, and then single plants were placed in a wind tunnel. The frontal area of the plant was photographed before and during 5 min of wind blowing at a velocity of 8 m s−1. The sediment that accumulated behind the plant was measured after the trial. The top 5 cm of the plant was then clipped away, and the plant was subjected to another wind-blowing trial. This experimental sequence was repeated until the above-ground part of the plant had been entirely removed. Although bending of S. krylovii in the wind was clearly apparent, bending ceased when the upper part of the plant body had been clipped away. Clipping reduced the frontal area, but there was little decrease in sediment accumulation until all of the above-ground biomass had been removed. These results indicated that sediment trapping by a single plant was likely attributable to the sheltering effect created by the lower part of the above-ground plant body; the flexible upper portion of the plant body apparently contributed very little to sediment trapping. The loss of the upper part of the bodies of grasses via grazing should therefore have little effect on sediment trapping when the plants are solitary or very sparsely dispersed.

Species identities impact the responses of intensity and importance of competition to the soil fertility changes

How plant competition varies with the changes of biotic and abiotic factors has been debated for a long time in the field of ecology. The aim of this study was to explore how neighbors and soil fertility influenced the intensity and importance of competition on species Stipa grandis and S. krylovii. We conducted a target species (S. grandis and S. krylovii) × soil fertility (low and high fertility) × competition treatment (4 treatments: two target species grown in monoculture and in mixture with each other, and in mixture with Leymus chinensis or Agropyron cristatum) microcosm experiment. We calculated the intensity (NIntA) and importance (NImpA) of neighbor-effect with additive symmetry for each target species under different treatments, and explored how the NIntA and NImpA were influenced by the target species, neighbor identity and soil fertility. We calculated the fertilizer-addition effect index on each target species to explore how neighbor identity influenced the index. (1) When target species in mixture with L. chinensis, both the NIntA and NImpA decreased with the increase of soil fertility. The NImpA was significantly negative on S. grandis under both soil fertility treatments and on S. krylovii under the high soil fertility treatment. (2) When target species in mixture with A. cristatum, the NIntA significantly influenced by the interaction between target species and soil fertility. The NImpA was significantly negative on S. grandis under the low soil fertility treatment and on S. krylovii under the high soil fertility treatment. (3) When in S. grandis – S. krylovii mixture system, the NIntA increased with the increase of soil fertility, and the NImpA showed no significant effects on each target species. (4) The fertilizer-addition effect was higher than zero for all treatments except the one on S. grandis in mixture with L. chinensis. The effect on S. krylovii was relatively lower than that on S. grandis in mixture with A. cristatum but was relatively higher in any of the other three competition treatments. The present findings demonstrated that the identities of both target and neighbor species influenced the fertilizer-addition effect and the responses of intensity and importance of competition to the changes of soil fertility. The present study showed the complexity of target species and neighbor identities in influencing the outcomes of plant competition, and provided novel insights into how plant competition driving the community dynamics in the context of soil fertility changes.

Development and Characterization of Wheat-Agropyron cristatum Introgression Lines Induced by Gametocidal Genes and Wheat ph1b Mutant

The P genome of Agropyron cristatum Gaertn. contains many desirable genes that can be utilized as genetic resources to improve wheat. In this research, we used both the gametocidal chromosome 2Cc and the pairing homologous gene (Ph1b) mutant to induce structural aberrations and translocations between wheat and the 4P, 5P, and 6P genome chromosomes. By using the two approaches, a total of 19 wheat-A. cristatum translocations have been identified, in which 13 were induced by the Triticum aestivum cv. Chinese Spring (CS) ph1b mutant (CS ph1b) and six were induced by gametocidal chromosome 2Cc from Aegilops cylindrica Host. The wheat-4P, -5P and -6P A. cristatum translocations were characterized by in situ hybridization and by a set of conserved orthologous set (COS) molecular markers. The aberrations included centromeric translocations, terminal translocations, dicentric translocations, and deletions. The average induction frequency of chromosome structural aberrations was 10.9% using gametocidal 2Cc chromosome and 8.8% using ph1b mutant. The highest frequency obtained was for chromosome 4P using both approaches. All the wheat-A. cristatum translocation lines obtained were valuable for identifying A. cristatum chromosome 4P, 5P, and 6P related genes. In addition, these lines provided genetic resources and new germplasm accessions for the genetic improvement of wheat.

An assessment of seed head and flag leaf contributions to reproductive effort in sagebrush steppe bunchgrasses

North American sagebrush-steppe bunchgrasses primarily establish from seed; however, the importance of parental plant carbon from flag leaves or within the seed head itself to reproduction in perennial bunchgrasses is unknown. To address this, we experimentally removed flag leaves and shaded seed heads to assess their importance to reproduction in the exotic bunchgrass crested wheatgrass (Agropyron cristatum), which has high seed head photosynthetic capacity and readily establishes from seed, and the native grass, squirreltail (Elymus elymoides), which has lower seed head photosysnthetic capacity and does not establish as readily from seed. We hypothesized that inflorescence shading would have a greater negative impact on crested wheatgrass reproduction than in squirreltail. In crested wheatgrass, shading did not affect total propagule production but did reduce both total filled seeds and filled seed specific mass (dry mass per unit area). Flag leaf removal stimulated seed filling and increased seed specific mass, especially in unshaded seed heads, suggesting flag leaves are competitive carbon sinks in crested wheatgrass. In contrast, flag leaf removal and shading in squirreltail resulted in similar reductions in total propagules, fewer filled seed produced and lower specific seed mass, indicating similar contributions to reproductive effort by both structures. These results indicate seed head photosynthetic activity is an adaptive reproductive feature in both grasses, but the contrasting effects of flag leaf removal may reflect long-term adaptive responses to grazing pressures that differed in crested wheatgrass's native range compared to those in North American sagebrush steppe.

Effects of Vegetation Restoration on the Structure and Function of the Rhizosphere Soil Bacterial Community of Solanum rostratum

Invasive plants can change soil microbial communities and therefore promote invasion. While vegetation restoration has been adopted in certain infested lands to curb the invasion of Solanum rostratum, changes in the composition and function of rhizosphere soil bacterial communities of the species before and after the restoration has not yet been reported. In this study, two vegetation combinations used in previous studies were selected as candidates:Astragalus adsurgens+Elymus dahuricus+Bromus inermis (T1) and A. adsurgens+Festuca arundinacea+Agropyron cristatum+Leymus chinensis (T2). Rhizosphere soil samples were collected from each combination (T1 and T2), a S. rostratum invaded area (SR), and the native plant (NP) control to analyze the bacterial community structure and diversity using 16S rDNA gene sequencing on the Illumina MiSeq platform. PICRUSt was further used to predict the functional abilities of soil bacterial communities. Results of 16S rDNA gene sequencing showed that both the Simpson and Chao1 indices were higher in the SR treatment than in the NP treatment, but neither reached a significant level, although both indices decreased significantly after vegetation restoration (T1 and T2; P<0.05). The relative abundance of Microvirga, Skermanella, and Sphingomonas from phylum Proteobacteria and Bryobacter from the phylum Acidobacteria were significantly lower in the SR treatment (P<0.05) when compared with the NP treatment and higher in restoration treatments (T1 and T2). The RDA analysis showed that soil organic matter (OM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), and available potassium (AK) were important factors affecting the composition of the bacterial community. Based on the PICRUSt analysis of soil bacterial community functions, the relative abundance of gene families related to biosynthesis of amino acids, purine metabolism, pyrimidine metabolism, ribosome, and aminoacyl-tRNA biosynthesis were higher in the rhizosphere samples of the SR treatment than those of the NP treatment and reduced significantly after vegetation restoration (T1 and T2; P<0.05). The structure and function of rhizosphere soil bacterial community of S. rostratum and vegetation restoration were analyzed and provided a theoretical basis for the invasion mechanism and ecological restoration of S. rostratum.

高寒典型草原主要物种的株高和盖度预测种群和群落地上生物量

为快速、准确、无破坏地测定草原地上生物量，在祁连山高寒典型草原植物生长旺季，观测了冬季和春秋季放牧地60个样方内各物种的株高、盖度等生长指标。以冬季牧地紫花针茅（Stipa purpurea）、醉马草（Achnatherum inebrians）、赖草（Leymus secalinus）、扁穗冰草（Agropyron cristatum）、二裂委陵菜（Potentilla bifurca）、银灰旋花（Convolvulus ammannii）6个主要物种的株高、盖度、株高和盖度的乘积为自变量，分别预测同物种、其他物种和群落地上生物量。用春秋季牧场的数据验证模型的精确性和稳定性。结果表明：主要物种的生长指标可预测其自身、其他物种和群落地上生物量。对自身种群，株高和盖度乘积的复合因子预测效果最好；4种禾草对其他物种、二裂委陵菜对菊科植物种群，株高、盖度单因子预测效果优于复合因子；6个主要物种单独或2-6个种结合均可预测群落地上生物量，但是以6个物种株高和盖度的乘积同时预测时决定系数最大，可解释群落地上生物量89.5%的变异，为高寒典型草原群落地上生物量最优预测模型。;In order to fastly, accurately and non-destructively to predict the biomass on alpine typical steppe in Qilian Mountains, growth indexes of plants species such as plant height, coverage were observed during the growing season under two different pastures, which are Winter grazing land and spring and autumn grazing land. In total 60 quadrats were measured. Taking the Plant height, coverage, the product of plant height and coverage of 6 major species in winter pasture,such as Stipa purpurea, Achnatherum inebrians, Leymus secalinus, Agropyron cristatum, Potentilla bifurca and Convolvulus ammannii as independent variable, and the main population, other populations and aboveground biomass of the community in the same quadrat were used to develop the predicted model, which was verified and corrected by applying the collected data under Vegetation data of Spring and Autumn Pasture. The results showed that the growth indices of representative species can predict the aboveground biomass of themselves, other species and communities. The composite factor of plant height and coverage product was the best for predicting the population. The single factor of plant height and coverage was better than the compound factor in predicting the other populations of the four grasses and the compositae populations of the Potentilla bifurca. Six main species alone or two to six kinds of combining both predictable community biomass on the ground, but the product of 6 species of plant height and coverage to participate in the prediction of regression curve at the same time, decision coefficient is the largest, can explain community biomass of 89.50% of the variation on the ground, can be used as a typical alpine steppe community biomass optimal prediction model on the ground.

Structure and ecological features of the Yeravninsky steppes flora (Western Transbaikalia)

The paper is devoted to the characteristics of the floristic diversity of steppe vegetation in the southern part of the Vitim plateau in Yeravninskaya and Uldurginskaya basins. There is a southern border of the permafrost. The flora of the steppes is characterized by a depleted composition in comparison with the steppes of the Selenga middle mountains. Some widespread plant species of the true steppes of the Central Asia are absent here. The basis of the ecological and phytocoenotic structure is the steppe group, which is dominated by mountain and forest-steppe plant species. There is less participation of the true steppe species; this fact indicates an insular nature of these steppes. A group of light-coniferous species is significant; they are the part of the cryoarid forest-steppe complexes of the Vitim plateau. In the ecological structure of the flora xeromesophyte and gemixerophyte species dominate. They have the most important coenotic role in the formation of the vegetation cover of these steppes. The cereals species are of high coenotic significance, there are indicators of the dry bunchgrass steppes of Southern Siberia (Poa botryoides (Trin. ex Griseb.) Roshev., Agropyron cristatum (L.) Gaertn., Koeleria cristata (L.) Pers.). The role of mesoxerophytic of East Asian and Daurian-Manchurian species is also high (Filifolium sibiricum (L.) Kitam., Stellera chamaejasme L., Bupleurum scorzonerifolium Willd.). They are typical for meadow steppes of the Central Asian sector of the Palearctic.

Cloning and characterization of a putative orthologue of the wheat vernalization (VRN1) gene in perennial wheatgrass (Agropyron cristatum)

AbstractFlowering time is important in the adaptation of crop plants to different environments and impacts the economic value of agricultural crops. Wheatgrass is a perennial Triticeae species and one of the most important grasses for pasture and forage in temperate regions of the world. Late heading is of interest in forage crop breeding programmes. Increasing the time to heading by molecular means may be facilitated by the identification and characterization of floral genes. In addition, the characterization of orthologous genes in wheatgrass is useful for establishing genetic relationships between grasses. In this study, we characterized a wheatgrass orthologue of the hexaploid wheat VRN‐A1 gene involved in the vernalization response. High sequence similarity of this gene, designated VRN‐P1, to both VRN‐A1 and VRN‐H1 and its localization on the 5PL chromosome arm in Agropyron cristatum indicated that VRN‐P1 is orthologous to VRN1 from wheat and barley. VRN‐P1 retains the VRN1 exon/intron organization and encodes a MADS‐box transcription factor. Phylogenetic and amino acid analyses confirmed that the isolated sequence represents VRN1. Furthermore, phylogenetic analysis of the deduced protein sequence revealed an intimate genetic relationship between VRN‐P1 and VRN1 from Triticeae species.

Sagebrush Bird Communities Differ with Varying Levels of Crested Wheatgrass Invasion

AbstractSagebrush communities, covering millions of hectares in the western United States, are among our most imperiled ecosystems. They are challenged by various anthropogenic stressors, including invasion by nonnative grasses that degrade habitat quality and alter ecosystem function. Sagebrush restoration efforts are underway to improve habitat conditions to benefit a wide range of sagebrush-dependent species. Because birds are good indicators of habitat quality, monitoring avian metrics is an effective way to measure progress of sagebrush restoration. We compared avian community composition and individual species abundance among three sagebrush–steppe habitat types with varying degrees of invasion by nonnative crested wheatgrass Agropyron cristatum at the Camas National Wildlife Refuge in southeastern Idaho, USA. Sagebrush-obligate birds, such as sage thrasher Oreoscoptes montanus and sagebrush sparrow Artemisiospiza nevadensis, were most abundant in sagebrush habitats with an understory of native grass. Community composition was similar between sagebrush habitats with native and nonnative grasses, but quite different from bird communities occupying crested wheatgrass. The Habitats and Populations Strategies database, a conservation planning tool, predicts that restoration of crested wheatgrass sites to sagebrush in poor or fair condition will increase the density of sagebrush-obligate bird species. Taken together, these results suggest that restoration of crested wheatgrass near-monocultures back to sagebrush will improve habitat value for much of the bird community whether or not the understory can be converted to primarily native grasses, or a mix of natives and nonnatives. Of the sagebrush bird species of concern, Brewer's sparrow Spizella breweri occupied sagebrush habitats with native vs. nonnative understory at similar abundances, and this species could serve as a metric of intermediate restoration success. However, sagebrush sparrow and sage thrasher, which were significant indicators of sagebrush with native grasses, will likely benefit most from full restoration of a native herbaceous understory. Grassland-obligate birds such as horned lark Eremophila alpestris and grasshopper sparrow Ammodramus savannarum were most abundant at crested wheatgrass–dominated sites and may not benefit from restoration back to shrubland; managers should understand potential trade-offs.

Soil and Plant Factors Affecting Changes in Forage Production Patterns on Mined Land 28 Yr After Reclamation

Coal surface mining in the northern Great Plains of the United States often produces mining spoils with physical and chemical barriers to successful revegetation, and this has resulted in experiments on reclamation with salvaged soil materials. There is a need to determine changes in soil properties and plant community and productivity decades after reclamation. Experiments were initiated in the mid-1970s by placing wedge-shaped masses of Haplustoll soils over leveled, saline-sodic mine spoils forming 2−5% hillslopes approximately 50 m long at two sites near Zap and Stanton, North Dakota. Seeding treatments at Zap included alfalfa (Medicago sativa L.), crested wheatgrass (CWG, Agropyron cristatum [L.] Gaertn.), smooth bromegrass (SBG, Bromus inermis Leyss.), and Russian wildrye (Psathyrostachy juncea [Fisch.] Nevski); at Stanton, native grasses (two Bouteloua spp.) replaced P. juncea. We examined soil, plant community, and productivity changes 3 decades after the start of the experiments. Leaching of soluble salts in subsoils and mine spoils improved soil quality (SQ). SQ improved more in lower slope areas because more rootzone was occupied by low SQ mine spoil. Initial forage yield patterns showed dependency on hillslope position, reflecting both soil depth effects in lower slope parts of hillslopes and apparent water redistribution effects in middle and upper slope areas. Evidence of SQ improvement over time was inferred by substantial decreases in yield dependency on hillslope position at both sites. The Zap site was grazed more heavily than Stanton, and species composition at Zap was 46% cool-season grasses (CWG greatest) and 40% broadleaves. Stanton had 87% cool-season grasses (SBG greatest) with 3% broadleaves. Leaching of salts was threefold greater at Zap and may have resulted from an abundance of deep-rooted broadleaves. Reclaiming mined land with salvaged soil and revegetation can improve SQ of mine spoil, which our results infer was driven by root growth and establishment of macroporosity.

Advancing crested wheatgrass [Agropyron cristatum (L.) Gaertn.] breeding through genotyping-by-sequencing and genomic selection.

Crested wheatgrass [Agropyron cristatum (L.) Gaertn.] provides high quality, highly palatable forage for early season grazing. Genetic improvement of crested wheatgrass has been challenged by its complex genome, outcrossing nature, long breeding cycle, and lack of informative molecular markers. Genomic selection (GS) has potential for improving traits of perennial forage species, and genotyping-by-sequencing (GBS) has enabled the development of genome-wide markers in non-model polyploid plants. An attempt was made to explore the utility of GBS and GS in crested wheatgrass breeding. Sequencing and phenotyping 325 genotypes representing 10 diverse breeding lines were performed. Bioinformatics analysis identified 827, 3,616, 14,090 and 46,136 single nucleotide polymorphism markers at 20%, 30%, 40% and 50% missing marker levels, respectively. Four GS models (BayesA, BayesB, BayesCπ, and rrBLUP) were examined for the accuracy of predicting nine agro-morphological and three nutritive value traits. Moderate accuracy (0.20 to 0.32) was obtained for the prediction of heading days, leaf width, plant height, clump diameter, tillers per plant and early spring vigor for genotypes evaluated at Saskatoon, Canada. Similar accuracy (0.29 to 0.35) was obtained for predicting fall regrowth and plant height for genotypes evaluated at Swift Current, Canada. The Bayesian models displayed similar or higher accuracy than rrBLUP. These findings show the feasibility of GS application for a non-model species to advance plant breeding.

Composition and spatial distribution of main species in grassland community of Baiyinhua mining area, China

We analyzed composition and spatial distribution of main species in the surrounding grassland of Baiyinhua mining area in Inner Mongolia. The results showed that there were 55 plant species in the grassland, with dominant species being Stipa grandis, Carex korshinskyi, and Cleistogenes squarrosa, and common species being Leymus chinensis, Agropyron cristatum, and Anemarrhena asphodeloides. The accumulative relative importance value of those six species was 79.6%, with their densities being 26.6, 204.7, 105.4, 107.1, 68.2 and 55.1 individuals·m-2, respectively. The population density of those six species was modeled by the semi-variance function. The population distribution was in accordance with the exponential model, exponential model, exponential model, spherical model, linear model and Gaussian model, respectively. Through analyzing the spatial distribution pattern, structure ratios were 59.2%, 97.2%, 89.1%, 94.5%, 62.6% and 72.1%, respectively. The spatial autocorrelation of C. korshinskyi, C. squarrosa and L. chinensis populations was mainly affected by structural factors, whereas S. grandis, A. cristatum and A. asphodeloides were mainly affected by random factors. According to results from the fractal dimension analysis, population distribution patterns of S. grandis, C. korshinskyi, C. squarrosa and A. cristatum were simple, and the spatial dependence was strong. Both L. chinensis and A. asphodeloides showed contrasting patterns with those four species. From 2D and 3D images, S. grandis and A. asphodeloides showed gradient diffusion, while C. korshinskyi, C. squarrosa, L. chinensis and A. cristatum showed patch distribution. The results showed that the spatial distribution of the main species in this grassland community did not correlate with mining.

Increasing rates of long-term nitrogen deposition consistently increased litter decomposition in a semi-arid grassland.

The continuing nitrogen (N) deposition observed worldwide alters ecosystem nutrient cycling and ecosystem functioning. Litter decomposition is a key process contributing to these changes, but the numerous mechanisms for altered decomposition remain poorly identified. We assessed these different mechanisms with a decomposition experiment using litter from four abundant species (Achnatherum sibiricum, Agropyron cristatum, Leymus chinensis and Stipa grandis) and litter mixtures representing treatment-specific community composition in a semi-arid grassland under long-term simulation of six different rates of N deposition. Decomposition increased consistently with increasing rates of N addition in all litter types. Higher soil manganese (Mn) availability, which apparently was a consequence of N addition-induced lower soil pH, was the most important factor for faster decomposition. Soil C:N ratios were lower with N addition that subsequently led to markedly higher bacterial to fungal ratios, which also stimulated litter decomposition. Several factors contributed jointly to higher rates of litter decomposition in response to N deposition. Shifts in plant species composition and litter quality played a minor role compared to N-driven reductions in soil pH and C:N, which increased soil Mn availability and altered microbial community structure. The soil-driven effect on decomposition reported here may have long-lasting impacts on nutrient cycling, soil organic matter dynamics and ecosystem functioning.

Creation of new forms of feeding cereal grasses from A to Z

Aim. To create a new cultivars of perennial cereal grasses with the high feeding and seed productivity, longevity, drought resistance and freezing tolerance in order to increase the quality of livestock super-elite seeds production. DNA certification of economically valuable properties estimation. Methods. Hybridization, a partially known combination. Embryo culture method from immature caryopsis with completion of growing in a nutrient medium. Techniques of plant tissue culture (initiation, multiplication, rooting and adaptation in vitro plants to ex vitro conditions. DNA certification was performed using SSR (Simple Sequence Repeat) marker system. Results. The new competitively cultivar of Agropyron cristatum "Malarytsky" have been created. The system of the cultivar and parental forms registration in the form of molecular genetic passports is presented. Conclusions. The cultivar of Agropyron cristatum "Malarytsky" was turned over to the State Institution “The State Inspection for Testing and Protection of Plant Varieties” for state testing and for inclusion in the State Register of Varieties. The economic efficiency of this new feeding culture cultivating for Belarus and countries with sharply continental climate is presented.&#x0D; Keywords: Agropyron cristatum, hybridization, cul populations, in vitro, water-soluble carbohydrates, DNA certification, molecular genetic passports, cultivar.

Molecular evidence for impoverished mycorrhizal communities of Agropyron cristatum compared with nine other plant species in the Northern Great Plains

Invasive plants may alter arbuscular mycorrhizal fungi (AMF) communities on which resident plants depend. To determine if the invader crested wheatgrass (Agropyron cristatum [L.] Gaertn.) associates with different AMF than resident plants, we compared AMF communities of six A. cristatum−dominated sites to five sagebrush steppe and three mixed-grass prairie sites in the Northern Great Plains. Consistent with findings on some other invaders, roots of A. cristatum were without AMF and supported fewer AMF operational taxonomic units than seven native species and two nonnative species. Restoring natives to A. cristatum sites is notoriously difficult. Our findings suggest a lack of soil mutualists may contribute to the difficulty.