Southern Ecotypes Research Articles

Seasonal photosynthesis and respiration dynamics of Pinus sibirica latitudinal ecotypes: ex situ study

Photosynthesis and respiration are temperature dependent processes. Therefore, it is important to understand how the physiological processes of photosynthesis and respiration will respond to climate change in the future. Seasonal carbon dioxide gas exchange of vegetative scion Siberian stone pine ecotypes (Pinus sibirica Du Tour) of latitudinal transect grown in the scientific station “Kedr” in the south of the Tomsk region were studied. The latitudinal transect was represented by two ecotypes: the southern ecotype (Tomsk) and the northern ecotype (Urengoy). The age of the grafted trees was 26 years. Apparent uptake of CO2 of the southern ecotype began a week earlier than the one of the southern ecotype, when the needle length reached 35 and 40 % of the final length of the southern and southern ecotypes, respectively. Photosynthesis reaches its maximum values when the needle length was 45-52 % of the final length of both ecotypes. The carbon dioxide assimilation rate of the southern ecotype remained high until the second decade of July, then its intensity decreased. Photosynthetic rate of the southern ecotype decreased in early August. In fully developed needles, the photosynthetic intensity between ecotypes did not differ significantly. The dark respiration of both ecotypes was maximum at the beginning of needle growth, then decreased significantly, was almost constant in July, and had minimum values at the end of the growing season. At the initial growth stages the needles of the southern ecotype had high values of dark respiration, which was 2 times higher than that of the southern ecotype. In the growth process by the first ten days of
 July, the differences between ecotypes were practically leveled. Subsequently, the dark respiration of the southern ecotype became 2 times higher than that of the southern one, however, it remained low compared to the initial stages of needle growth. The respiration of needle finished growing decreased by 8-10 times. The negative balance between photosynthesis and respiration of both ecotypes maintained until the needle length exceed 40 % and 35 % of the final length in the northern and southern ecotypes, respectively. Positive balance CO2 was observed when the needle length reached 45 % in the northern and 52 % in the southern ecotypes. During the summer months the CO2 balance was significantly higher for the Tomsk ecotype. In September and October the CO2 balance of the northern ecotype became lower than of one the southern one due to increased part of respiration of gas exchange. We believe that the high respiratory intensity of the Siberian stone pine northern ecotype is hereditary, therefore significant respiratory costs will have negative impact the productivity of high latitude plants and their adaptation to climate warming.

The effectiveness of cultivating soybean varieties of different maturity groups in the conditions of the central Ciscaucasia

The studies were conducted in 2017-2019 at the experimental station of the Stavropol State Agrarian University in conditions without irrigation and on the basis of the experimental plots of Agrosakhar LLC with the use of irrigation. The territories of the research sites belong to the zone of unstable humidification, characterized by unstable and uneven precipitation during the growing season of soybeans, elevated air temperatures in summer, when soybean plants enter the phases of flowering and grain filling. At the experimental plots of the SSAU experimental station, the soil is represented by leached chernozem, at the experimental sites of Agrosahar LLC by ordinary chernozem. The purpose of the research is to determine the biological characteristics and efficiency of growing new, promising soybean varieties of the southern ecotype. It was found that the most quickly-ripening variety with a growing season of 96 days is the Bara variety, the longest growing season was noted in the mid-ripening Vilana variety – 129 days. The maximum photosynthetic potential of soybean crops was formed under irrigation conditions: quickly-ripening Selecta 101 variety – 1376, early-ripening Duar variety – 1678 and mid-ripening Zara variety – 2167 thous. m2.day/ha. In terms of yield, when growing soybeans without irrigation in the quickly-ripening group, the Lira variety stood out – 1.59 t/ha, in the early-ripening Selecta 201 variety – 1.75 t/ha and the midripening Zara variety – 1.94 t/ha, when irrigation was used in the quickly-ripening group, the Selecta 101 variety stood out – 2.34 t/ha, in the early-ripening Duar variety – 2.89 t/ha and the mid-ripening Zara variety – 3.14 t/ha. In the conditions of the SSAU experimental station without irrigation and in Agrosakhar LLC the largest profit in the amount of 16028 to 40912 rub./ha was obtained by cultivating the mid-ripening Zara variety with a yield of 1.94 - 3.14 t/ha, and the level of profitability ranged from 49.4 to 108.8%.

Temperature has a major effect on the cuticular wax composition of bilberry (Vaccinium myrtillus L.) fruit.

Cuticle is the first layer protecting plants against external biotic and abiotic factors and is responsive to climatic factors as well as determined by genetic adaptations. In this study, the chemical composition of bilberry fruit cuticular wax was investigated through a latitudinal gradient from Latvia (56°N 24°E) through Finland (65°N 25°E) to northern Norway (69°N 18°E) in two seasons 2018 and 2019. Changes in the major cuticular wax compounds, including triterpenoids, fatty acids, alkanes, aldehydes, ketones, and primary alcohols, were detected by GC-MS analysis. Generally, a decreasing trend in the proportion of triterpenoids from southern to northern latitudes, accompanied with an increase in proportion of fatty acids, aldehydes, and alkanes, in bilberry fruit cuticular wax was observed. A correlation analysis between climatic factors with proportion of wax compounds indicated that temperature was the main factor affecting the cuticular wax composition in bilberries. A controlled phytotron experiment with southern and northern bilberry ecotypes confirmed the major effect of temperature on bilberry fruit cuticular wax load and composition. Elevated temperature increased wax load most in berries of northern ecotypes. The level of triterpenoids was higher, while levels of fatty acids and alkanes were lower, in wax of bilberry fruits ripened at 18°C compared to 12°C in both northern and southern ecotypes. Based on our results, it can be postulated that the predicted increase in temperature due to climate change leads to alterations in fruit cuticular wax load and composition. In northern ecotypes, the alterations were especially evident.

Landscape Genomics Provides Evidence of Ecotypic Adaptation and a Barrier to Gene Flow at Treeline for the Arctic Foundation Species Eriophorum vaginatum.

Global climate change has resulted in geographic range shifts of flora and fauna at a global scale. Extreme environments, like the Arctic, are seeing some of the most pronounced changes. This region covers 14% of the Earth’s land area, and while many arctic species are widespread, understanding ecotypic variation at the genomic level will be important for elucidating how range shifts will affect ecological processes. Tussock cottongrass (Eriophorum vaginatum L.) is a foundation species of the moist acidic tundra, whose potential decline due to competition from shrubs may affect ecosystem stability in the Arctic. We used double-digest Restriction Site-Associated DNA sequencing to identify genomic variation in 273 individuals of E. vaginatum from 17 sites along a latitudinal gradient in north central Alaska. These sites have been part of 30 + years of ecological research and are inclusive of a region that was part of the Beringian refugium. The data analyses included genomic population structure, demographic models, and genotype by environment association. Genome-wide SNP investigation revealed environmentally associated variation and population structure across the sampled range of E. vaginatum, including a genetic break between populations north and south of treeline. This structure is likely the result of subrefugial isolation, contemporary isolation by resistance, and adaptation. Forty-five candidate loci were identified with genotype-environment association (GEA) analyses, with most identified genes related to abiotic stress. Our results support a hypothesis of limited gene flow based on spatial and environmental factors for E. vaginatum, which in combination with life history traits could limit range expansion of southern ecotypes northward as the tundra warms. This has implications for lower competitive attributes of northern plants of this foundation species likely resulting in changes in ecosystem productivity.

Responses of root phenology in ecotypes of Eriophorum vaginatum to transplantation and warming in the Arctic

The effect of climate change on phenology and growth is less understood for belowground plant tissues than for aboveground plant tissues, particularly in high-latitude regions. Ecotypes within a species adapted to a locality may display different responses to climate change.We established two common garden plots in the Arctic tundra north of the Brooks Range in northern Alaska. Three ecotypes of Eriophorum vaginatum along a latitudinal gradient were transplanted into common gardens, and half of the transplants were warmed using open-top chambers (OTCs). Minirhizotrons were used to track the root phenology during the growing seasons of 2016 and 2017.Warming with OTCs (approximately +1 °C in air) did not affect the root biomass, root production or root phenology. The southern ecotype (from 67°16′N) of Eriophorum vaginatum transplanted northward experienced delayed startup and root production compared to two northern ecotypes (from 68°38′N and 69°25′N), although significant differences were not observed in the three ecotypes in terms of root production, root biomass and growth duration at the two sites. Our results suggest that as the climate warms, ecotypes of Eriophorum vaginatum may be able to adjust their duration of root growth and root productivity by phenotypic plasticity, although the degree of plasticity controlling the root startup time may vary between southern and northern ecotypes.

Intraspecific variation in phenology offers resilience to climate change for Eriophorum vaginatum

The phenology of Arctic plants is an important determinant of the pattern of carbon uptake and may be highly sensitive to continued rapid climate change. Eriophorum vaginatum L. (Cyperaceae) has a disproportionate influence over ecosystem processes in moist acidic tundra, but it is unclear whether its growth and phenology will remain competitive in the future. We investigated whether northern tundra ecotypes of E. vaginatum could extend their growing season in response to direct warming and transplanting into southern ecosystems. At the same time, we examined whether southern ecotypes could adjust their growth patterns in order to thrive further north, should they disperse quickly enough. Detailed phenology measurements across three reciprocal transplant gardens over a 2-year period showed that some northern ecotypes were capable of growing for longer when conditions were favourable, but their biomass and growing season length was still shorter than those of the southern ecotype. Southern ecotypes retained large leaf length when transplanted north and mirrored the growing season length better than the others, mainly owing to immediate green-up after snowmelt. All ecotypes retained the same senescence timing, regardless of environment, indicating a strong genetic control. Eriophorum vaginatum may remain competitive in a warming world if southern ecotypes can migrate north.

The results of divergence of early-maturing maize source material in heterosis breeding

Purpose. To analyze the divergence of early maturing source material of corn Zea mays L. in heterosis breeding for the genetic base formation at the State Institution the Institute of Grain Crops of the NAAS of Ukraine.Methods. Field (comprehensive assessment of morphobiological and economically valuable characteristics of the source material and maize hybrids) individual selection, cumulative and recurrent selection, backross and testcrosses bree­ding methods; laboratory; analysis and synthesis; statistical.Results. The results of research on the analysis of the divergence of early maturing corn source material in the conditions of the Steppe of Ukraine has become a developed harmonized working collection of corn breeding samples adapted to the stressful conditions of this region. The gradual cyclical improvement of the lines made it possible to form the core of the genetic diversity of FAO 150–290 early maturing specimens of the southern ecotype, which are competitive in heterosis breeding. The complexity of breeding for early maturity in the steppe conditions is due to the lack of material adapted to the stress factors of the South of Ukraine. The available early maturing lines of the world collection F2, F7, Ер1, Ма21, Ма23, Со125, Со255, См7, PLS61, S72, etc., were distinguished by high cold resistance, good starting plant development, intensive accumulation of dry matter during ripening, but not adapted to the deficiency of moisture in the soil and high summer temperatures. According to the results of the experiment, it was revealed that, in terms of breeding, lines of Lancaster plasma (DK427 and DK633) were the most plastic, due to which a number of new mid-early lines were obtained, for example DK2/427, DK267, DK266/417, DK633/266, DK296, etc., which were included in the registered hybrids. Formation of the genetic base of early maturing maize source material for heterosis breeding and systematization accor­ding to different breeding characteristics provided a balance of samples of alternative components, which will be further used to model heterosis hybrids in the early maturing group.Conclusions. The updated basic collection of lines is represented by the samples of plasma Iodent: DK744SVZM, DK216SVZM, DK4173SVZM, DK235zS, DK257zM, SV, DK365SVZM, DK777ZMSV, DK733-7zM,SV, DK315SVZM; Lancaster: DK296zS,VM, DK633/266zS,VM, DK2965ZSZM, DK2953 ZSZM, DK3023 ZSZM, DK236zS,ZM; Raid (SSS): DK232MV, DK2323MV, DK239MV; Mixed: DK253ZSZM, DK273MV, DK272zS, DK281SV, DK233zM,SV, DK959MV, DK9527 ZSZM, DK247MV, DK2442MV, which is the basis of the genetic diversity of early ripening corn samples included in the State register of plant varie­ties suitable for dissemination in Ukraine.

PRODUCTIVITY OF ALFALFA DEPENDENT FROM VARIETY FEATURES AND HYDRO-THERMAL CONDITIONS OF THE RIGHT BANK FOREST STEPPE

The article presents the results of studies of the effect of seeding rates and row spacing on the forage productivity of different alfalfa ecotypes when mowing grass in the flowering stage. In the soil-climatic conditions of the right bank forest-steppe irrespective of the effect of abiotic and biotic factors during the growing season, high adaptability of alfalfa of the southern ecotype of the Angelica variety was established, which formed a stable crop of green mass at the optimal seeding rate (8,0 million/ha) and width 12,5 cm. For an average of two years of grass use, the varieties of alfalfa Rosana and Angelica provided a yield of green mass of 62,96-64,02 t/ha, which was 11,1-14,9% higher than for sowing with the norm of sowing 4,0 million/ha, and 6,3-7,1% with row spacing half (25,0 cm). It was found that in two years of use of alfalfa Angelica variety had higher dry matter content, compared with the variety of Rosana and were respectively 23,05 and 22,98%. There was a gradual decrease in the dry matter content with a thickening of the herbage in the Rosana variety from 23,32 to 22,72% and from the Angelica variety from 23,31 to 22,84%. As the row spacing increased from 12,5 to 25,0 cm, the solids content increased by 0,28-0,62%, or 22,74-22,84 and 23,12-23,36%. The crude protein content in the dry matter of alfalfa plants of both varieties differed by slopes and years of herb use. The highest content of crude protein was obtained in the dry matter for sowing with a row spacing of 12,5 cm, which averaged 21,10% in the Rosana variety and 20,23% in the Angelica variety or increased by 0,79-0,87%, compared to the row spacing of 25,0 cm. Thus, irrespective of the hydrothermal conditions during the growing season of the studied varieties of alfalfa sowing Rosana and Angelika, the average yield of dry matter at the level of 13,64-13,93 and 2,76-2,88 t/ha of crude protein at the width of row 12,5 cm. Key words: alfalfa, variety, flowering start, crude protein, dry matter, yield, green mass.

Siberian stone pine intraspecies variation in growth, cone bearing and pest resistance when grown in the south of the Tomsk region

The analysis of growth, seed production and pest resistance was carried out in 24-year old clones from5 latitudinal, 4 longitudinal and 5 altitudinal ecotypes of Siberian stone pine in the clone archive. Northern and highaltitudinal ecotypes had the weakest growth, weak or absent seed production, and were also severely damaged bypests. The local ecotype had average growth and reproduction rates. Southern and mid-eastern ecotypes had intensivevegetative growth, abundant seed production and absolute resistance to pests. They had the optimal combination of traitsfor plantation cultivation.

Climatic oscillations in Quaternary have shaped the co-evolutionary patterns between the Norway spruce and its host-associated herbivore

During the Last Glacial Maximum in the Northern Hemisphere, expanding ice sheets forced a large number of plants, including trees, to retreat from their primary distribution areas. Many host-associated herbivores migrated along with their host plants. Long-lasting geographic isolation between glacial refugia could have been led to the allopatric speciation in separated populations. Here, we have studied whether the migration history of the Norway spruce Picea abies in Quaternary has affected its host-associated herbivorous beetle—Monochamus sartor. By using microsatellite markers accompanied by the geometric morphometrics analysis of wing venation, we have revealed the clear geographic structure of M. sartor in Eurasia, encompassing two main clusters: southern (Alpine–Carpathian) and eastern (including northeastern Europe and Asia), which reflects the northern and southern ecotypes of its host. The two beetles’ lineages probably diverged during the Pleniglacial (57,000—15,000 BC) when their host tree species was undergoing significant range fragmentation and experienced secondary contact during post-glacial recolonization of spruce in the Holocene. A secondary contact of divergent lineages of M. sartor has resulted in the formation of the hybrid zone in northeastern Europe. Our findings suggest that the climatic oscillations during the Pleistocene have driven an insect-plant co-evolutionary process, and have contributed to the formation of the unique biodiversity of Europe.

Assisted migration across fixed seed zones detects adaptation lags in two major North American tree species.

Boreal forests are experiencing dramatic climate change, having warmed 1.0°–1.9°C over the last century. Yet forest regeneration practices are often still dictated by a fixed seed zone framework, in which seeds are both harvested from and planted into predefined areas. Our goal was to determine whether seedlings sourced from southern seed zones in Minnesota USA are already better adapted to northerly seed zones because of climate change. Bur oak (Quercus macrocarpa) and northern red oak (Quercus rubra) seedlings from two seed zones (i.e., tree ecotypes) were planted into 16 sites in two northern seed zones and measured for 3 yr. Our hypotheses were threefold: (1) tree species with more southern geographic distributions would thrive in northern forests where climate has already warmed substantially, (2) southern ecotypes of these species would have higher survival and growth than the northern ecotype in northern environments, and (3) natural selection would favor seedlings that expressed phenotypic and phenological traits characteristic of trees sourced from the more southern seed zone. For both species, survival was high (>93%), and southern ecotypes expressed traits consistent with our climate adaptation hypotheses. Ecotypic differences were especially evident for red oak; the southern ecotype had had higher survival, lower specific leaf area (SLA), faster height and diameter growth, and extended leaf phenology relative to the northern ecotype. Bur oak results were weaker, but the southern ecotype also had earlier budburst and lower SLA than the northern ecotype. Models based on the fixed seed zones failed to explain seedling performance as well as those with continuous predictors (e.g., climate and geographical position), suggesting that plant adaptations within current seed zone delineations do align with changing climate conditions. Adding support for this conclusion, natural selection favored traits expressed by the more southern tree ecotypes. Collectively, these results suggest that state seed sourcing guidelines should be reexamined to permit plantings across seed zones, a form of assisted migration. More extensive experiments (i.e., provenance trails) are necessary to make species‐specific seed transfer guidelines that account for climate trends while also considering the precise geographic origin of seed sources.

Arbuscular Mycorrhizal Fungi Mediate Drought Tolerance and Recovery in Two Contrasting Carob (Ceratonia siliqua L.) Ecotypes by Regulating Stomatal, Water Relations, and (In)Organic Adjustments.

Irregular precipitation and drought caused an increase in tree mortality rates in multiple forest biomes with alterations in both ecosystem services and carbon balance. Carob (Ceratonia siliqua) growth and production in arid and semi-arid ecosystems are likely affected by climate change-induced droughts. Understanding the physiological responses of drought-induced early-stage tree death and strategies to enhance drought tolerance and optimize growth will help tree improvement programs. Mycorrhizal inoculation has a pronounced impact on plant growth, water absorption, mineral nutrition, and protection from abiotic stresses. However, a better understanding of these complex interconnected cellular processes and arbuscular mycorrhizal fungi (AMF)-mediated mechanisms regulating drought tolerance in plants will enhance its potential application as an efficient approach for bio-amelioration of stresses. The objectives of this work were to elucidate the different effects of autochthone AMF on inorganic solute and water content uptakes, organic adjustments (sugar and proteins content), leaf gas exchange (stomatal conductance and efficiency of photosystems I and II), and oxidative damage of two contrasting ecotypes of carob seedlings: coastal (southern ecotype (SE)) and in-land (northern ecotype (NE)) under control (C), drought (by cessation of irrigation for 15 days (15D)), and recovery (R) conditions. Our findings showed that AMF promoted growth, nutrient content, and physiological and biochemical parameters in plants of both ecotypes during C, 15D, and R conditions. After four days of recovery, stomatal conductance (gs), the maximum photochemical efficiency of PSII (Fv/Fm), water content, and plant uptake of mineral nutrients (P, K, Na, and Ca) were significantly higher in shoots of mycorrhizal (AM) than non-mycorrhizal (NM) control plants. Consequently, AMF reduced to a greater degree the accumulation of hydrogen peroxide (H2O2) and oxidative damage to lipid (malondialdehyde (MDA)) content in AM than NM plants in NE and SE, after recovery. Altogether, our findings suggest that AMF can play a role in drought resistance of carob trees at an early stage by increasing the inorganic solutes (P, K, Na, and Ca), water content uptake, organic solutes (soluble sugars and protein content), stomatal conductance, and defense response against oxidative damage during re-watering after drought stress.

Differential responses of ecotypes to climate in a ubiquitous Arctic sedge: implications for future ecosystem C cycling.

The response of vegetation to climate change has implications for the carbon cycle and global climate. It is frequently assumed that a species responds uniformly across its range to climate change. However, ecotypes - locally adapted populations within a species - display differences in traits that may affect their gross primary productivity (GPP) and response to climate change. To determine if ecotypes are important for understanding the response of ecosystem productivity to climate we measured and modeled growing season GPP in reciprocally transplanted and experimentally warmed ecotypes of the abundant Arctic sedge Eriophorum vaginatum. Transplanted northern ecotypes displayed home-site advantage in GPP that was associated with differences in leaf area index. Southern ecotypes exhibited a greater response in GPP when transplanted. The results demonstrate that ecotypic differentiation can impact the morphology and function of vegetation with implications for carbon cycling. Moreover they suggest that ecotypic control of GPP may limit the response of ecosystem productivity to climate change. This investigation shows that ecotypes play a substantial role in determining GPP and its response to climate. These results have implications for understanding annual to decadal carbon cycling where ecotypes could influence ecosystem function and vegetation feedbacks to climate change.

КАЧЕСТВО ЗЕРНА КОЛЛЕКЦИОННЫХ ОБРАЗЦОВ ЯРОВОЙ МЯГКОЙ ПШЕНИЦЫ РАЗНОГО ЭКОЛОГО-ГЕОГРАФИЧЕСКОГО ПРОИСХОЖДЕНИЯ В СТЕПНОЙ ЗОНЕ ОРЕНБУРГСКОЙ ОБЛАСТИ

In scientific work the estimation of technological parameters of grain of wheat varieties of different ecological groups is presented at cultivation in steppe of Orenburg region. Investigations of qualitative properties of grain of spring soft wheat revealed that high-grade grain forms varieties of steppe Volga, eastern and southern ecotypes. More vitreous grains are characteristic of varieties of steppe Volga and eastern ecological groups. Grain with a protein content of 14% and higher is characterized by varieties of forest-steppe West Siberian and forest-steppe eastern, steppe Volga, steppe eastern and steppe southern ecological groups. A high content of gluten (33-34%) was noted in varieties of the steppe Volga, eastern and southern ecotypes. From all studied ecotypes, a grain was obtained with quality gluten of Groups I-III. Most of the varieties of the forest-steppe West Siberian and eastern, steppe Volga, eastern and southern ecological groups in the steppe zone of the Orenburg region form 1-2 grade grains, and samples of forest North Russian and East Siberian forest ecological groups - 3-4 classes.

Genomewide evidence of environmentally mediated secondary contact of European green crab (Carcinus maenas) lineages in eastern North America.

Genetic‐environment associations are increasingly revealed through population genomic data and can occur through a number of processes, including secondary contact, divergent natural selection, or isolation by distance. Here, we investigate the influence of the environment, including seasonal temperature and salinity, on the population structure of the invasive European green crab (Carcinus maenas) in eastern North America. Green crab populations in eastern North America are associated with two independent invasions, previously shown to consist of distinct northern and southern ecotypes, with a contact zone in southern Nova Scotia, Canada. Using a RAD‐seq panel of 9,137 genomewide SNPs, we detected 41 SNPs (0.49%) whose allele frequencies were highly correlated with environmental data. A principal components analysis of 25 environmental variables differentiated populations into northern, southern, and admixed sites in concordance with the observed genomic spatial structure. Furthermore, a spatial principal components analysis conducted on genomic and geographic data revealed a high degree of global structure (p < .0001) partitioning a northern and southern ecotype. Redundancy and partial redundancy analyses revealed that among the environmental variables tested, winter sea surface temperature had the strongest association with spatial structuring, suggesting that it is an important factor defining range and expansion limits of each ecotype. Understanding environmental thresholds associated with intraspecific diversity will facilitate the ability to manage current and predict future distributions of this aquatic invasive species.

Growth and reproduction in Pinus sibirica ecotypes from Western Siberia in a common garden experiment

Experimental studies of forest trees’ intraspecies variations in reproduction and reproductive allocation are scarce. Such studies are relevant for the Siberian stone pine (Pinus sibirica Du Tour) because of the high value of its seeds and wood. To reveal growth and reproductive variations among Siberian stone pine ecotypes in relation to the climate of the provenances, we examined their growth height, crown diameter, stem volume, number of female cones, and male shoots, at different ages, in the clonal common garden experiment established in 1996 in Russia. Scions were obtained from 11 to 19 randomly selected 100–170-year old trees in each of four natural stands located on the latitudinal transect on the West Siberian plain. They were grafted onto local 4 year old Siberian stone pine seedlings and grown in a common garden experiment comprising nine plots near the southern margin of the species’ natural range. Growth traits were affected by climatic conditions in the provenances: generally, a warmer climate was associated with more rapid growth. Variation among the ecotypes at the graft age of 12 years was not large; however, it significantly increased by the age of 19. The relationship was ambiguous between reproductive traits and the climate of the provenances. The proportion of female, male and bisexual clones varied among years in all ecotypes. Most of the clones had only female cones; male clones were less common. The southern ecotype showed rapid growth and formed the lowest number of male shoots and female cones. The northern ecotype showed the weakest growth and moderate cone bearing, along with abundant male flowering. The intermediate ecotypes had a moderate growth and the highest numbers of cones, along with moderate numbers of male shoots. These results demonstrate the fundamental differences in the patterns and nature of variation in growth and reproductive traits.

Elevated CO2 boosts reproduction and alters selection in northern but not southern ecotypes of allergenic ragweed.

Many plants increase reproduction in response to rising levels of atmospheric CO2 . However, environmental and genetic variation across heterogeneous landscapes can lead to intraspecific differences in the partitioning of CO2 -induced carbon gains to reproductive tissue relative to growth. We measured the effects of rising atmospheric CO2 on biomass allocation in the allergenic plant Ambrosia artemisiifolia (common ragweed) across a geographic climate gradient. We grew plants from three latitudes at 400, 600, and 800 µL·L-1 CO2 and analyzed biomass allocation and natural selection on flowering phenology and growth. Both the latitude of origin and CO2 treatment had significant effects on allocation and on estimates of selection. Northern plants were under stronger selection than southern plants to flower quickly, and they produced larger seeds and more reproductive mass per unit of growth. Northern plants were under stronger selection than southern plants to flower quickly, and they produced larger seeds and more reproductive mass per unit of growth. While all plants grew larger and produced heavier seeds at higher CO2 , only northern plants increased male flower production. Both size and time to flowering were under selection, with a relaxation of the size-fitness function in northern ecotypes at high CO2 . Northern ecotypes allocate more CO2 -induced carbon gains to reproduction than do southern plants, pointing to a geographic gradient in future pollen and seed production by this species arising from local adaptation. Relaxed selection on size at elevated CO2 could amplify reproductive enhancements to northern ecotypes, although more growth and seed provisioning can be expected overall. Our results demonstrate potential for ecotypic divergence in ragweed responses to climate change.

Comparison of the Chemical Properties of Soil and the Main Components of the Southern Ecotype Garlic Cultivar Cultivated in the Volcanic or Nonvolcanic Ash Soil of Jeju Island

본 연구에서 제주의 화산회토와 비화산회토에서 난지형 마늘인 남도 마늘과 대서 마늘을 재배하여 토양 및 마늘의 성분을 비교 분석하였다. 남도 마늘을 재배한 화산회토양에서는 전기전도도 및 가용성 황 함량이 높았으며 대서 마늘을 재배한 화산 회토양에서는 유기물함량 및 총 질소함량이 높게 나타났다. 남도 마늘을 재배한 비화산회토의 경우 가용성 인 함량이 높게 나타났다. 화산회토에서 재배한 남도 마늘의 경우 가용성고형물 및 알리신 함량이 높았으며, 화산회토에서 재배한 대서 마늘의 경우 환원당 함량이 높게 나타났다. 또한 제주에서 재배된 마늘의 대량원소 함량은 칼륨이 가장 높았으며 다음으로 황, 마그네슘, 칼슘 및 나트륨 순이었으며 미량원소의 경우 철, 아연, 망간, 구리 순이었다. 이러한 결과는 고품질 마늘 생산을 목표로 하는 재배농가들에게 유용한 정보를 제공하게 될 것이다.

Molecular cloning and expression of a 9-cis-epoxy carotenoid dioxygenase gene (NCED) and its relationship to dormancy in Lilium longiflorum and L. formosanum

SummaryIndividuals in northern populations of Lilium longiflorum in the Ryukyu Archipelago between Japan and Taiwan exhibit deep dormancy which is induced by high temperatures in the Summer, while plants of southern ecotypes and L. formosanum show no dormancy. In higher plants, 9-cis-epoxycarotenoid dioxygenase (NCED) is the critical enzyme for the regulation of abscisic acid (ABA) biosynthesis.The relationships between levels of expression of the LlNCED gene (GenBank Accession No. KC357734) and endogenous ABA levels were examined in 1-year-old seedlings of an L. formosanum population domesticated in Fukuoka (FFU) and in two L. longiflorum populations native to Pitouchiao (LPI), Taiwan, or Kikai Jima (LKI), Japan. The deduced amino acid sequences of the NCED proteins shared high identity with NCED proteins in other monocotyledons, and were closely related to enzymes in other members of the class Liliopsida. A high correlation was observed between levels of LlNCED gene expression and ABA concentration. Seedlings from LKI had the highest level of expression of LlNCED in August, while seedlings from FFU had the lowest level. Higher expression of the LlNCED gene in mid-Summer in the dormant population was related to higher endogenous concentrations of ABA. These results provide evidence that the induction of deep dormancy was initiated by the accumulation of ABA in dormant types of L. longiflorum, which was induced by high Summer temperatures.

Relative effects of temperature vs. photoperiod on growth and cold acclimation of northern and southern ecotypes of the grass Arrhenatherum elatius

Growth of perennial grasses in the fall represents a balance between an extended growing season and increased vulnerability to frost. Within species along latitudinal gradients, plants may exhibit ecotype-specific sensitivities to the temperature and photoperiod cues that influence cold acclimation. Therefore, it is unclear for a given latitude how climate warming will alter the timing and extent of cold acclimation, and thus vulnerability to frost events. We evaluated relative temperature and photoperiod sensitivities during simulated cold acclimation for two northern (Swedish) and two southern (Italian) ecotypes of the common forage grass Arrhenatherum elatius. Three temperature levels (Templow: 3°C, Temphigh+low: 8°C followed by 3°C, and Temphigh: 8°C) were crossed with 2 photoperiod levels (Photoshort: 6h, and Photolong: 12h) and administered to the plants for a three week acclimation period. All plants were then frozen at −8°C for 1d, and post-frost growth was measured after 3 weeks. Temphigh and Photolong increased growth prior to frost, but resulted in decreased growth after frost. The effects of temperature on sugar concentration, biomass and flower presence depended on photoperiod, with temperature only influencing sugar concentration and flowering at Photoshort, while Photolong increased biomass only at the high temperature. The faster growth rate of southern A. elatius ecotypes before frost, in combination with sufficient cold acclimation, resulted in higher biomass accumulation after frost. The faster growth habit of southern ecotypes may be advantageous in accumulating higher summer biomass even after moderate frost events in the fall.