scholarly journals Climate change, snow mold and the Bromus tectorum invasion: mixed evidence for release from cold weather pathogens

AoB Plants ◽  
2019 ◽  
Vol 11 (5) ◽  
Author(s):  
Danielle M Smull ◽  
Nicole Pendleton ◽  
Andrew R Kleinhesselink ◽  
Peter B Adler

Abstract Climate change is reducing the depth and duration of winter snowpack, leading to dramatic changes in the soil environment with potentially important ecological consequences. Previous experiments in the Intermountain West of North America indicated that loss of snowpack increases survival and population growth rates of the invasive annual grass Bromus tectorum; however, the underlying mechanism is unknown. We hypothesized that reduced snowpack might promote B. tectorum population growth by decreasing damage from snow molds, a group of subnivean fungal pathogens. To test this hypothesis, we conducted greenhouse and field experiments to investigate the interaction between early snowmelt and either fungicide addition or snow mold infection of B. tectorum. The greenhouse experiment confirmed that the snow mold Microdochium nivale can cause mortality of B. tectorum seedlings. In the field experiment, early snowmelt and fungicide application both increased B. tectorum survival, but their effects did not interact, and snow mold inoculation had no effect on survival. We did find interactive effects of snowmelt and fungal treatments on B. tectorum seed production: with ambient snowpack, M. nivale inoculation reduced seed production and fungicide increased it, whereas in the early snowmelt treatment seed production was high regardless of fungal treatment. However, treatment effects on seed production did not translate directly to overall population growth, which did not respond to the snow melt by fungal treatment interaction. Based on our mixed results, the hypothesis that reduced snowpack may increase B. tectorum fitness by limiting the effects of plant pathogens deserves further investigation.

2019 ◽  
Vol 116 (26) ◽  
pp. 12901-12906 ◽  
Author(s):  
Diane R. Campbell

How climate change influences the dynamics of plant populations is not well understood, as few plant studies have measured responses of vital rates to climatic variables and modeled the impact on population growth. The present study used 25 y of demographic data to analyze how survival, growth, and fecundity respond to date of spring snowmelt for a subalpine plant. Fecundity was estimated by seed production (over 15 y) and also divided into flower number, fruit set, seeds per fruit, and escape from seed predation. Despite no apparent effects on flower number, plants produced more seeds in years with later snowmelt. Survival and probability of flowering were reduced by early snowmelt in the previous year. Based on demographic models, earlier snowmelt with warming is expected to lead to negative population growth, driven especially by changes in seedling establishment and seed production. These results provide a rare example of how climate change is expected to influence the dynamics of a plant population. They furthermore illustrate the potential for strong population impacts even in the absence of more commonly reported visual signs, such as earlier blooming or reduced floral display in early melting years.


Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1718
Author(s):  
Audrey J. Harvey ◽  
Lisa J. Rew ◽  
Tim S. Prather ◽  
Jane M. Mangold

The impacts of climate change are expected to alter the abundance and distribution of invasive annual grasses, such as Bromus tectorum L. (cheatgrass) and Ventenata dubia (Leers) Coss. (ventenata). High temperature extremes will be more frequent and for longer periods, and increased atmospheric CO2 is expected to double even with the most conservative estimates. Climate change draws concern for the potential success of winter annual grasses in arid and semi-arid plant communities. Information on B. tectorum’s growth response to climate change in laboratory and field experiments are available for monocultures; however, more knowledge is needed on the response when growing with other invasive grasses, such as V. dubia. We examined differences in seedling growth for V. dubia and B. tectorum growing alone and with each other under current (4 °C/23 °C at 400 ppm CO2) and elevated (10.6 °C/29.6 °C at 800 ppm CO2) climate conditions. There was one trial per climate scenario with 10 replications per competition type (inter-, intra-specific competition for each species). Bromus tectorum was larger than V. dubia across climate and competition treatments, but contrary to previous studies, both species were smaller in the elevated climate treatment. Ventenata dubia allocated more growth to its roots than B. tectorum across both climate treatments, indicating V. dubia may have a competitive advantage for soil resources now and in the future.


2012 ◽  
Vol 151 (2) ◽  
pp. 163-188 ◽  
Author(s):  
P. JUROSZEK ◽  
A. von TIEDEMANN

SUMMARYClimate change biology is witnessing a significant quantity of new publications each year, which compromises efforts to keep up-to-date on the rapidly growing body of climate change biology literature. The present paper provides an overview on research approaches and challenges in climate change biology with respect to plant pathogens, insect pests and weeds (collectively termed ‘pests’ here). It also summarizes the suggestions of researchers about how to conceptualize and prioritize future research strategies. Recently published key studies demonstrate that climate change research is qualitatively advancing and that the interactions among environmental and biotic factors which have been found are complex. This complexity hinders attempts to generalize responses of pests to changes in climate. The challenge remains to identify the most significant causal relationships and to separate them from other factors such as crop management practices, which may also influence the observed changes in pest distribution and prevalence in managed ecosystems. In addition, the present overview shows that there are still gaps in many research areas, while other fields have been intensively investigated. For example, the identification of potential benefits in plant protection that may emerge from future climate change has not been explored as extensively as the potential threats. However, encouraging developments can be observed in recent climate change research, for instance the increased number of studies performed under subtropical and tropical climatic conditions, the increased availability of results from multi-factorial field experiments and modelling studies do consider increasingly pest–crop–climate interactions. Further progress can be expected, provided that researchers, sponsors and other stakeholders maintain their interest in climate change biology research.


2012 ◽  
Vol 163 (12) ◽  
pp. 481-492
Author(s):  
Andreas Rigling ◽  
Ché Elkin ◽  
Matthias Dobbertin ◽  
Britta Eilmann ◽  
Arnaud Giuggiola ◽  
...  

Forest and climate change in the inner-Alpine dry region of Visp Over the past decades, observed increases in temperature have been particularly pronounced in mountain regions. If this trend should continue in the 21st Century, frequency and intensity of droughts will increase, and will pose major challenges for forest management. Under current conditions drought-related tree mortality is already an important factor of forest ecosystems in dry inner-Alpine valleys. Here we assess the sensitivity of forest ecosystems to climate change and evaluate alternative forest management strategies in the Visp region. We integrate data from forest monitoring plots, field experiments and dynamic forests models to evaluate how the forest ecosystem services timber production, protection against natural hazards, carbon storage and biodiver-sity will be impacted. Our results suggest that at dry low elevation sites the drought tolerance of native tree species will be exceeded so that in the longer term a transition to more drought-adapted species should be considered. At medium elevations, drought and insect disturbances as by bark beetles are projected to be important for forest development, while at high elevations forests are projected to expand and grow better. All of the ecosystem services that we considered are projected to be impacted by changing forest conditions, with the specific impacts often being elevation-dependent. In the medium term, forest management that aims to increase the resilience of forests to drought can help maintain forest ecosystem services temporarily. However, our results suggest that relatively rigid management interventions are required to achieve significant effects. By using a combination of environmental monitoring, field experiments and modeling, we are able to gain insight into how forest ecosystem, and the services they provide, will respond to future changes.


Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1452
Author(s):  
Raluca-Maria Pârlici ◽  
Aurel Maxim ◽  
Stefania Mirela Mang ◽  
Ippolito Camele ◽  
Lucia Mihalescu ◽  
...  

Organic berry plantations have been gaining popularity among farmers during recent years. Even so, farmers experience serious challenges in disease control management, which is a concern in organic farming. Phragmidiumrubi-idaei (DC) P. Karst is the pathogen responsible for blackberry and raspberry rust disease, one of the most present and active diseases in plantations. The antifungal certified products found on the organic farming market offer the opportunity for an efficient control strategy over plant pathogens in fruit shrub plantations. In this study, 5 natural based products—namely Altosan, Mimox, Canelys, Zitron, and Zeolite—were tested for their fungistatic effect over P. rubi-idaei. The experiments were carried out under laboratory conditions, performing observations over the impact of organic products, used at different concentration levels, on rust conidia germination. Moreover, field experiments were conducted in order to evaluate the efficiency of different treatments for rust control on raspberry (‘Polka’, ‘Veten’ and ‘Heritage’) and blackberry (‘Thorn Free’, ‘Chester’ and ‘Loch Ness’) varieties. Data analysis based on ANOVA tests showed significant differences between the tested variants and the control sample at p < 0.001. Furthermore, LSD test confirmed differences between all substances tested (p < 0.005). The natural products Canelys (formulated with cinnamon) and Zytron (based on citrus extract) have proven the highest inhibitory capacity for conidia germination during in vitro tests registering values of 80.42% and 78.34%, respectively. The same high inhibitory rates against rust pathogen were kept also in the field tests using the same two natural-based products mentioned earlier. In addition, outcomes from this study demonstrated that Zeolite is not recommended for raspberry or blackberry rust control.


Atmosphere ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 927
Author(s):  
Jamshad Hussain ◽  
Tasneem Khaliq ◽  
Muhammad Habib ur Rahman ◽  
Asmat Ullah ◽  
Ishfaq Ahmed ◽  
...  

Rising temperature from climate change is the most threatening factor worldwide for crop production. Sustainable wheat production is a challenge due to climate change and variability, which is ultimately a serious threat to food security in Pakistan. A series of field experiments were conducted during seasons 2013–2014 and 2014–2015 in the semi-arid (Faisalabad) and arid (Layyah) regions of Punjab-Pakistan. Three spring wheat genotypes were evaluated under eleven sowing dates from 16 October to 16 March, with an interval of 14–16 days in the two regions. Data for the model calibration and evaluation were collected from field experiments following the standard procedures and protocols. The grain yield under future climate scenarios was simulated by using a well-calibrated CERES-wheat model included in DSSAT v4.7. Future (2051–2100) and baseline (1980–2015) climatic data were simulated using 29 global circulation models (GCMs) under representative concentration pathway (RCP) 8.5. These GCMs were distributed among five quadrants of climatic conditions (Hot/Wet, Hot/Dry, Cool/Dry, Cool/Wet, and Middle) by a stretched distribution approach based on temperature and rainfall change. A maximum of ten GCMs predicted the chances of Middle climatic conditions during the second half of the century (2051–2100). The average temperature during the wheat season in a semi-arid region and arid region would increase by 3.52 °C and 3.84 °C, respectively, under Middle climatic conditions using the RCP 8.5 scenario during the second half-century. The simulated grain yield was reduced by 23.5% in the semi-arid region and 35.45% in the arid region under Middle climatic conditions (scenario). Mean seasonal temperature (MST) of sowing dates ranged from 16 to 27.3 °C, while the mean temperature from the heading to maturity (MTHM) stage was varying between 12.9 to 30.4 °C. Coefficients of determination (R2) between wheat morphology parameters and temperature were highly significant, with a range of 0.84–0.96. Impacts of temperature on wheat sown on 15 March were found to be as severe as to exterminate the crop before heading. The spikes and spikelets were not formed under a mean seasonal temperature higher than 25.5 °C. In a nutshell, elevated temperature (3–4 °C) till the end-century can reduce grain yield by about 30% in semi-arid and arid regions of Pakistan. These findings are crucial for growers and especially for policymakers to decide on sustainable wheat production for food security in the region.


Weed Science ◽  
2020 ◽  
pp. 1-10
Author(s):  
Muhammad Javaid Akhter ◽  
Per Kudsk ◽  
Solvejg Kopp Mathiassen ◽  
Bo Melander

Abstract Field experiments were conducted in the growing seasons of 2017 to 2018 and 2018 to 2019 to evaluate the competitive effects of rattail fescue [Vulpia myuros (L.) C.C. Gmel.] in winter wheat (Triticum aestivum L.) and to assess whether delayed crop sowing and increased crop density influence the emergence, competitiveness, and fecundity of V. myuros. Cumulative emergence showed the potential of V. myuros to emerge rapidly and under a wide range of climatic conditions with no effect of crop density and variable effects of sowing time between the two experiments. Grain yield and yield components were negatively affected by increasing V. myuros density. The relationship between grain yield and V. myuros density was not influenced by sowing time or by crop density, but crop–weed competition was strongly influenced by growing conditions. Due to very different weather conditions, grain yield reductions were lower in the growing season of 2017 to 2018 than in 2018 to 2019, with maximum grain yield losses of 22% and 50% in the two growing seasons, respectively. The yield components, number of crop ears per square meter, and 1,000-kernel weight were affected almost equally, reflecting that V. myuros’s competition with winter wheat occurred both early and late in the growing season. Seed production of V. myuros was suppressed by delaying sowing and increasing crop density. The impacts of delayed sowing and increasing crop density on seed production of V. myuros highlight the potential of these cultural weed control tactics in the long-term management programs of this species.


Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 768
Author(s):  
Jerónimo Vázquez-Ramírez ◽  
Susanna E. Venn

The early life-history stages of plants, such as germination and seedling establishment, depend on favorable environmental conditions. Changes in the environment at high altitude and high latitude regions, as a consequence of climate change, will significantly affect these life stages and may have profound effects on species recruitment and survival. Here, we synthesize the current knowledge of climate change effects on treeline, tundra, and alpine plants’ early life-history stages. We systematically searched the available literature on this subject up until February 2020 and recovered 835 potential articles that matched our search terms. From these, we found 39 studies that matched our selection criteria. We characterized the studies within our review and performed a qualitative and quantitative analysis of the extracted meta-data regarding the climatic effects likely to change in these regions, including projected warming, early snowmelt, changes in precipitation, nutrient availability and their effects on seed maturation, seed dormancy, germination, seedling emergence and seedling establishment. Although the studies showed high variability in their methods and studied species, the qualitative and quantitative analysis of the extracted data allowed us to detect existing patterns and knowledge gaps. For example, warming temperatures seemed to favor all studied life stages except seedling establishment, a decrease in precipitation had a strong negative effect on seed stages and, surprisingly, early snowmelt had a neutral effect on seed dormancy and germination but a positive effect on seedling establishment. For some of the studied life stages, data within the literature were too limited to identify a precise effect. There is still a need for investigations that increase our understanding of the climate change impacts on high altitude and high latitude plants’ reproductive processes, as this is crucial for plant conservation and evidence-based management of these environments. Finally, we make recommendations for further research based on the identified knowledge gaps.


Author(s):  
Brian Stiber ◽  
Asfaw Beyene

Climate change, drought, population growth and increased energy and water costs are all forces driving exploration into alternative, sustainable resources. The abundance of untapped wave energy often presents an opportunity for research into exploiting this resource to meet the energy and water needs of populated coastal regions. This paper investigates the potential and impact of harnessing wave energy for the purpose of seawater desalination. First the SWAN wave modeling software was used to evaluate the size and character of the wave resource. These data are used to estimate the cost of water for wave-powered desalination taking a specific region as a case example. The results indicate that, although the cost of water from this technology is not economically competitive at this time, the large available resource confirms the viability of significantly supplementing current freshwater supplies. The results also confirm that research into the feasibility of wave power as a source of energy and water in the area is warranted, particularly as water and energy become more scarce and expensive coinciding with the maturity of commercial wave energy conversion.


Sign in / Sign up

Export Citation Format

Share Document