Does the higher root carbon contribution to soil under cropping cycles following grassland conversion also increase shoot biomass?

We studied the growth responses of boreal Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L. Karst.) and silver birch (Betula pendula Roth) seedlings to simulated climate warming of an average of 1.3 °C over the growing season in a controlled field experiment in central Finland. We had six replicate plots for elevated and ambient temperature for each tree species. The warming treatment lasted for the conifers for three growing seasons and for the birch two growing seasons. We measured the height and diameter growth of all the seedlings weekly during the growing season. The shoot and root biomass and their ratios were measured annually in one-third of seedlings harvested from each plot in autumn. After two growing seasons, the height, diameter and shoot biomass were 45%, 19% and 41% larger in silver birch seedlings under the warming treatment, but the root biomass was clearly less affected. After three growing seasons, the height, diameter, shoot and root biomass were under a warming treatment 39, 47, 189 and 113% greater in Scots pine, but the root:shoot ratio 29% lower, respectively. The corresponding responses of Norway spruce to warming were clearly smaller (e.g., shoot biomass 46% higher under a warming treatment). As a comparison, the relative response of height growth in silver birch was after two growing seasons equal to that measured in Scots pine after three growing seasons. Based on our findings, especially silver birch seedlings, but also Scots pine seedlings benefitted from warming, which should be taken into account in forest regeneration in the future.

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Evaluation of salinity tolerance indices in North African barley accessions at reproductive stage

Czech Journal of Genetics and Plant Breeding ◽

10.17221/50/2017-cjgpb ◽

2019 ◽

Vol 55 (No. 2) ◽

pp. 61-69 ◽

Cited By ~ 3

Author(s):

Dorsaf Allel ◽

Anis BenAmar ◽

Mounawer Badri ◽

Chedly Abdelly

Keyword(s):

Salt Tolerance ◽

Grain Yield ◽

Salinity Tolerance ◽

Selection Criteria ◽

Reproductive Stage ◽

Shoot Biomass ◽

Salt Tolerant ◽

North African ◽

Grain Number ◽

Selection Indices

Soil salinity is one of the main factors limiting cereal productivity in worldwide agriculture. Exploitation of natural variation in local barley germplasm is an effective approach to overcome yield losses. Three gene pools of North African Hordeum vulgare L. grown in Tunisia, Algeria and Egypt were evaluated at the reproductive stage under control and saline conditions. Assessment of stress tolerance was monitored using morphological, yield-related traits and phenological parameters of reproductive organs showing significant genetic variation. High heritability and positive relationships were found suggesting that some traits associated with salt tolerance could be used as selection criteria. The phenotypic correlations revealed that vegetative traits including shoot biomass, tiller number and leaf number along with yield-related traits such as spike number, one spike dry weight, grain number/plant and grain number/spike were highly positively correlated with grain yield under saline conditions. Hence, these traits can be used as reliable selection criteria to improve barley grain yield. Keeping a higher shoot biomass and longer heading and maturity periods as well as privileged filling ability might contribute to higher grain production in barley and thus could be potential target traits in barley crop breeding toward improvement of salinity tolerance. Multiple selection indices revealed that salt tolerance trait index provided a better discrimination of barley landraces allowing selection of highly salt-tolerant and highly productive genotypes under severe salinity level. Effective evaluation of salt tolerance requires an integration of selection indices to successfully identify and characterize salt tolerant lines required for valuable exploitation in the management of salt-affected areas.

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Rice safety and control of penoxsulam resistant and susceptible barnyardgrass (Echinochloa crus-galli) populations with soil-applied herbicides

Weed Technology ◽

10.1017/wet.2021.17 ◽

2021 ◽

pp. 1-26

Author(s):

Tingting Liu ◽

Jialin Yu ◽

Jiapeng Fang ◽

Liyao Dong

Keyword(s):

Rice Fields ◽

Shoot Biomass ◽

Rice Varieties ◽

And Control

Abstract Resistance to penoxsulam among barnyardgrass populations is prevalent in rice fields in China. Seeds of penoxsulam-resistant (AXXZ-2) and -susceptible (JLGY-3) barnyardgrass populations, as well as the seeds of two rice varieties including Wuyungeng32 (WY) and Liangyou669 (LY) were planted in plastic pots and then treated with a rate titration of acetochlor, anilofos, butachlor, clomazone, oxadiazon, pendimethalin, pretilachlor, pyraclonil, or thiobencarb. The two barnyardgrass populations exhibited similar susceptibility to acetochlor, anilofos, butachlor, oxadiazon, pretilachlor, or pyraclonil. However, the susceptibility differed between the barnyardgrass populations in response to clomazone, pendimethalin, and thiobencarb. For AXXZ-2, herbicide rates that caused 50% reduction in shoot biomass from the nontreated control (GR50) were 179, >800, and 1798 g ha-1 for clomazone, pendimethalin, and thiobencarb, respectively; while JLGY-3 GR50 values were 61, 166, and 552 g ha-1, respectively. Both rice varieties demonstrated excellent tolerance to acetochlor, butachlor, oxadiazon, pretilachlor, and thiobencarb. However, substantial rice damage was observed with anilofos and clomazone. Anilofos at 352 g ha-1 and clomazone at 448 g ha-1 reduced rice shoot biomass by 41 and 50% from the nontreated, respectively. Averaged across herbicide rates, clomazone reduced rice shoot biomass from the nontreated control by 52 and 34% for WY and LY, respectively; and pendimethalin reduced rice shoot biomass from the nontreated control by 25 and 9% for WY and LY, respectively.

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Antagonism of chloride and nitrate inhibits nitrate reductase activity in chloride-stressed maize

Plant Growth Regulation ◽

10.1007/s10725-020-00685-2 ◽

2021 ◽

Author(s):

Xudong Zhang ◽

Bastian L. Franzisky ◽

Lars Eigner ◽

Christoph‐Martin Geilfus ◽

Christian Zörb

Keyword(s):

Zea Mays ◽

Polyethylene Glycol ◽

Nitrate Reductase ◽

Osmotic Stress ◽

Nitrate Reductase Activity ◽

Reductase Activity ◽

Shoot Biomass ◽

Lower Intensity ◽

Maize Variety ◽

Osmotic Balance

AbstractChloride (Cl−) is required for photosynthesis and regulates osmotic balance. However, excess Cl− application negatively interacts with nitrate ($${\mathrm{NO}}_{3}^{-}$$ NO 3 - ) uptake, although its effect on $${\mathrm{NO}}_{3}^{-}$$ NO 3 - metabolism remains unclear. The aim was to test whether Cl− stress disturbs nitrate reductase activity (NRA). A maize variety (Zea mays L. cv. LG 30215) was hydroponically cultured in a greenhouse under the following conditions: control (2 mM CaCl2), moderate Cl− (10 mM CaCl2), high Cl− (60 mM CaCl2). To substantiate the effect of Cl− stress further, an osmotic stress with lower intensity was induced by 60 g polyethylene glycol (PEG) 6000 L−1 + 2 mM CaCl2), which was 57% of the osmotic pressure being produced by 60 mM CaCl2. Results show that high Cl− and PEG-induced osmotic stress significantly reduced shoot biomass, stomatal conductance and transpiration rate, but NRA was only decreased by high Cl− stress. The interference of NRA in chloride-stressed maize is supposed to be primarily caused by the antagonistic uptake of Cl− and $${\mathrm{NO}}_{3}^{-}$$ NO 3 - .

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The Potential of Rhizoctonia-Like Fungi for the Biological Protection of Cereals against Fungal Pathogens

Plants ◽

10.3390/plants10020349 ◽

2021 ◽

Vol 10 (2) ◽

pp. 349

Author(s):

Dominik Bleša ◽

Pavel Matušinský ◽

Romana Sedmíková ◽

Milan Baláž

Keyword(s):

Biological Control ◽

Fungal Pathogens ◽

Plant Pathogens ◽

Higher Plants ◽

Fusarium Culmorum ◽

Suppressive Effect ◽

Plant Production ◽

Shoot Biomass ◽

Organic Substrates

The use of biological control is becoming a common practice in plant production. One overlooked group of organisms potentially suitable for biological control are Rhizoctonia-like (Rh-like) fungi. Some of them are capable of forming endophytic associations with a large group of higher plants as well as mycorrhizal symbioses. Various benefits of endophytic associations were proved, including amelioration of devastating effects of pathogens such as Fusarium culmorum. The advantage of Rh-like endophytes over strictly biotrophic mycorrhizal organisms is the possibility of their cultivation on organic substrates, which makes their use more suitable for production. We focused on abilities of five Rh-like fungi isolated from orchid mycorrhizas, endophytic fungi Serendipita indica, Microdochium bolleyi and pathogenic Ceratobasidium cereale to inhibit the growth of pathogenic F. culmorum or Pyrenophora teres in vitro. We also analysed their suppressive effect on wheat infection by F. culmorum in a growth chamber, as well as an effect on barley under field conditions. Some of the Rh-like fungi affected the growth of plant pathogens in vitro, then the interaction with plants was tested. Beneficial effect was especially noted in the pot experiments, where wheat plants were negatively influenced by F. culmorum. Inoculation with S. indica caused higher dry shoot biomass in comparison to plants treated with fungicide. Prospective for future work are the effects of these endophytes on plant signalling pathways, factors affecting the level of colonization and surviving of infectious particles.

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Evaluation of Image-Based Phenotyping Methods for Measuring Water Yam (Dioscorea alata L.) Growth and Nitrogen Nutritional Status under Greenhouse and Field Conditions

Agronomy ◽

10.3390/agronomy11020249 ◽

2021 ◽

Vol 11 (2) ◽

pp. 249

Author(s):

Emmanuel Frossard ◽

Frank Liebisch ◽

Valérie Kouamé Hgaza ◽

Delwendé Innocent Kiba ◽

Norbert Kirchgessner ◽

...

Keyword(s):

Management Practices ◽

Leaf Surface ◽

Plant Traits ◽

Soil Surface ◽

Shoot Biomass ◽

N Content ◽

Total Leaf ◽

Image Pixels ◽

Leaf N Content ◽

Yield Formation

New management practices must be developed to improve yam productivity. By allowing non-destructive analyses of important plant traits, image-based phenotyping techniques could help developing such practices. Our objective was to determine the potential of image-based phenotyping methods to assess traits relevant for tuber yield formation in yam grown in the glasshouse and in the field. We took plant and leaf pictures with consumer cameras. We used the numbers of image pixels to derive the shoot biomass and the total leaf surface and calculated the ‘triangular greenness index’ (TGI) which is an indicator of the leaf chlorophyll content. Under glasshouse conditions, the number of pixels obtained from nadir view (view from the top) was positively correlated to shoot biomass, and total leaf surface, while the TGI was negatively correlated to the SPAD values and nitrogen (N) content of diagnostic leaves. Pictures taken from nadir view in the field showed an increase in soil surface cover and a decrease in TGI with time. TGI was negatively correlated to SPAD values measured on diagnostic leaves but was not correlated to leaf N content. In conclusion, these phenotyping techniques deliver relevant results but need to be further developed and validated for application in yam.

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Semiarid bunchgrasses accumulate molybdenum on alkaline copper mine tailings: assessing phytostabilization in the greenhouse

SN Applied Sciences ◽

10.1007/s42452-021-04732-z ◽

2021 ◽

Vol 3 (8) ◽

Author(s):

Paul M. Antonelli ◽

Matthew G. Coghill ◽

Wendy C. Gardner ◽

Lauchlan H. Fraser

Keyword(s):

Mine Tailings ◽

Soil Amendments ◽

Block Design ◽

Wood Chip ◽

Biomass Accumulation ◽

Shoot Biomass ◽

Tissue Samples ◽

Copper Mine ◽

Copper Mine Tailings ◽

Randomized Complete Block Design

AbstractPhytostabilization is the use of plants and soil amendments to physically stabilize and remediate contaminated mine wastes and to control wind and water erosion in semiarid environments. The aim of this study was to evaluate two native bunchgrass species’ (Pseudoroegneria spicata and Festuca campestris) biomass accumulation and metals uptake response to locally available soil amendments (compost, wood ash and wood chips) to determine their suitability for phytostabilization at an alkaline copper mine tailings site in British Columbia, Canada. In the greenhouse, bunchgrasses important as forage for livestock and wildlife were grown in tailings with various ash–compost–wood chip combinations and evaluated using a randomized complete block design with 13 treatments and 10 replicates. Plants were harvested after 90 d, and tissues were analyzed for root and shoot biomass. Tissue samples (n = 3) from three treatment subsets (ash, compost, blend) were selected for elemental analysis. Biomass increased with increasing compost applications, and the response was greatest for P. spicata. Shoot molybdenum exceeded the maximum tolerable level for cattle and was significantly higher when grasses were grown on the ash treatment (183–202 mg kg−1) compared to the others (19.7–58.3 mg kg−1). Translocation and root bioconcentration factors were highest on the ash treatment (2.53–12.5 and 1.75–7.96, respectively) compared to the other treatments (0.41–3.43 and 1.47–4.79, respectively) and indicate that both species are ‘accumulators.’ The findings suggest that these bunchgrasses were not ideal candidates for phytostabilization due to high shoot tissue molybdenum accumulation, but provide important considerations for mine restoration in semiarid grassland systems.

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Root Response to Soil Water Status via Interaction of Crop Genotype and Environment

Agronomy ◽

10.3390/agronomy11040708 ◽

2021 ◽

Vol 11 (4) ◽

pp. 708

Author(s):

Phanthasin Khanthavong ◽

Shin Yabuta ◽

Hidetoshi Asai ◽

Md. Amzad Hossain ◽

Isao Akagi ◽

...

Keyword(s):

Soil Moisture ◽

Soil Water ◽

Root Distribution ◽

Water Status ◽

Soil Layer ◽

Shoot Biomass ◽

Soil Conditions ◽

Crop Adaptation ◽

Soil Moisture Status ◽

Root Distributions

Flooding and drought are major causes of reductions in crop productivity. Root distribution indicates crop adaptation to water stress. Therefore, we aimed to identify crop roots response based on root distribution under various soil conditions. The root distribution of four crops—maize, millet, sorghum, and rice—was evaluated under continuous soil waterlogging (CSW), moderate soil moisture (MSM), and gradual soil drying (GSD) conditions. Roots extended largely to the shallow soil layer in CSW and grew longer to the deeper soil layer in GSD in maize and sorghum. GSD tended to promote the root and shoot biomass across soil moisture status regardless of the crop species. The change of specific root density in rice and millet was small compared with maize and sorghum between different soil moisture statuses. Crop response in shoot and root biomass to various soil moisture status was highest in maize and lowest in rice among the tested crops as per the regression coefficient. Thus, we describe different root distributions associated with crop plasticity, which signify root spread changes, depending on soil water conditions in different crop genotypes as well as root distributions that vary depending on crop adaptation from anaerobic to aerobic conditions.

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Co-application of a biosolids product and biochar to two coarse-textured pasture soils influenced microbial N cycling genes and potential for N leaching

Scientific Reports ◽

10.1038/s41598-020-78843-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sanjutha Shanmugam ◽

Sasha N. Jenkins ◽

Bede S. Mickan ◽

Noraini Md Jaafar ◽

Falko Mathes ◽

...

Keyword(s):

Soil Ph ◽

Clayey Soil ◽

Chemical Properties ◽

Subterranean Clover ◽

N Cycling ◽

Shoot Biomass ◽

N Leaching ◽

Physical And Chemical ◽

Microbial N ◽

And Chemical Properties

AbstractCo-application of biochar and biosolids to soil has potential to mitigate N leaching due to physical and chemical properties of biochar. Changes in N cycling pathways in soil induced by co-application of biological amendments could further mitigate N loss, but this is largely unexplored. The aim of this study was to determine whether co-application of a biochar and a modified biosolids product to three pasture soils differing in texture could alter the relative abundance of N cycling genes in soil sown with subterranean clover. The biosolids product contained lime and clay and increased subterranean clover shoot biomass in parallel with increases in soil pH and soil nitrate. Its co-application with biochar similarly increased plant growth and soil pH with a marked reduction in nitrate in two coarse textured soils but not in a clayey soil. While application of the biosolids product altered in silico predicted N cycling functional genes, there was no additional change when applied to soil in combination with biochar. This supports the conclusion that co-application of the biochar and biosolids product used here has potential to mitigate loss of N in coarse textured soils due to N adsoption by the biochar and independently of microbial N pathways.

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