Increased absorption and translocation contribute to improved efficacy of dicamba to control early growth stage Palmer amaranth (Amaranthus palmeri) – CORRIGENDUM

Weed Science ◽  
2020 ◽  
Vol 68 (6) ◽  
pp. 681-681
Author(s):  
Ivan Cuvaca ◽  
Randall Currie ◽  
Kraig Roozeboom ◽  
Jack Fry ◽  
Mithila Jugulam
Keyword(s):  
Growth Stage ◽  
Early Growth ◽  
Palmer Amaranth ◽  
Amaranthus Palmeri ◽  
Early Growth Stage

Increased Absorption and Translocation Contribute to Improved Efficacy of Dicamba to Control Early Growth Stage Palmer amaranth (Amaranthus palmeri)

Weed Science ◽  
2019 ◽  
pp. 1-25 ◽  
Author(s):  
Ivan Cuvaca ◽  
Randall Currie ◽  
Kraig Roozeboom ◽  
Jack Fry ◽  
Mithila Jugulam
Keyword(s):  
Effective Dose ◽  
Logistic Model ◽  
Growth Stage ◽  
Fold Increase ◽  
Early Growth ◽  
Palmer Amaranth ◽  
Shoot Biomass ◽  
Amaranthus Palmeri ◽  
Application Timing ◽  
Early Growth Stage

Abstract Rapid growth of Palmer amaranth (Amaranthus palmeri S. Watson) poses a challenge for timely management of this weed. Dose response studies were conducted in 2017 and 2018 under field and greenhouse conditions near Garden City and Manhattan, KS, respectively, to evaluate the efficacy of dicamba to control ≤10 cm, 15 cm, and 30 cm tall-Palmer amaranth that mimics three herbicide application timing: on time application (Day 0), and 1 (Day 1) and 4 days (Day 4) delay. Visual injury rating and reduction in shoot biomass (% of non-treated), and mortality were assessed at four weeks after treatment using a three- and four-parameter log-logistic model, in R software program. Increasing dicamba doses increased A. palmeri control regardless of plant height both in the field and greenhouse studies. The results suggest that delaying application one (15 cm) and four days (30 cm), resulted in a two- and 27-fold increase in the effective dose of dicamba on A. palmeri, respectively, under field conditions. However, in the greenhouse, for the same level of A. palmeri control, more than one- and two-fold increase in dicamba dose, respectively was required. Similarly, the effective dose of dicamba required for 50% reduction in A. palmeri shoot biomass (GR50) increased more than four- and eight-fold or more than one- and two-fold when dicamba application was delayed by one (15 cm) and four days (30 cm), in the field or in the greenhouse, respectively. To understand the basis of increased efficacy of dicamba in controlling early growth stage of A. palmeri, dicamba absorption and translocation studies were conducted. Results indicate a significant reduction in dicamba absorption (7%) and translocation (15%) with increase in A. palmeri height. Therefore, increased absorption and translocation of dicamba results in increased efficacy in improving A. palmeri control at early growth stage.

scholarly journals Temporal Dynamics of Microcystins In Two Reservoirs With Different Trophic Status During The Early Growth Stage of Cyanobacteria

2021 ◽  
Author(s):  
Qingju Xue ◽  
Ming Kong ◽  
Liqiang Xie ◽  
Tong Li ◽  
Mengna Liao ◽  
...  
Keyword(s):  
Growth Stage ◽  
Trophic Status ◽  
Temporal Dynamics ◽  
Influence Factors ◽  
Environmental Parameters ◽  
Early Growth ◽  
Cyanobacterial Blooms ◽  
Organic Matters ◽  
Early Growth Stage ◽  
Density And Biomass

Abstract Harmful cyanobacterial blooms are increasing in frequency and severity, which makes their toxic secondary metabolites of microcystins (MCs) have been widely studied, especially in their distribution and influence factors in different habitats. However, the distribution of MCs on the early growth stage of harmful cyanobacteria and its influence factors and risks are still largely unknown. Thus, in the present study, two reservoirs (Lutian Reservoir and Lake Haitang) with different trophic status in China have been studied weekly from March to May in 2018, when the cyanobacteria communities were just in the early growth stage, to investigate the variation of MCs concentration and the relationships between MCs and environmental parameters. During the investigation, Lutian Reservoir and Lake Haitang were found to be mesotrophic and light eutrophic, respectively. In Lutian Reservoir, the concentration of EMCs was obviously higher than that of IMCs with a mean value of 0.323 and 0.264 μg/L, respectively. Meanwhile, the concentration of EMCs also fluctuated more sharply than that of IMCs. Congeners of IMC-YR and EMC-LR were respectively dominant in total concentrations of IMCs and EMCs. Unsurprisingly, in Lake Haitang, the concentrations of IMC and EMC were both significantly higher than that in Lutian Reservoir with a mean concentration of 0.482 and 0.472 μg/L, respectively. Differently, the concentration of MC-YR was dominant in both IMCs and EMCs, followed by MC-LR. In correlation analysis, the IMCs were significantly and positively correlated with the density and biomass of phytoplankton phyla and potential MCs-producing cyanobacteria and the parameters of water temperature (WT), nutrients and organic matters. Similar results were also observed for EMCs. While the different variation of MCs in two reservoirs might be primarily caused by the differences in WT, nutrients (especially phosphorus), organic matters and the composition of MCs-producing cyanobacteria. In addition, the coexistence of the dominant species of Pseudoanabaena sp., which can produce taste-and-odor compound of 2-methylisoborneol (2-MIB), might have significant impacts on the concentration and toxicity of MCs. Our results suggested that the risks posed by MCs at the early growth stage of cyanobacteria should also deserve our attentions, especially in mesotrophic water bodies.

scholarly journals Growth, Development, and Chemical Constituents of Edible Ice Plant (Mesembryanthemum crystallinum L.) Produced under Combinations of Light-emitting Diode Lights

HortScience ◽  
2018 ◽  
Vol 53 (6) ◽  
pp. 865-874 ◽  
Author(s):  
Thitipat Weeplian ◽  
Tsair-Bor Yen ◽  
Yunn-Shy Ho
Keyword(s):  
Vegetative Growth ◽  
Growth Stage ◽  
Chemical Constituents ◽  
Early Growth ◽  
Mesembryanthemum Crystallinum ◽  
Light Spectrum ◽  
Light Emitting ◽  
Early Growth Stage ◽  
Light Spectra ◽  
Late Growth

To investigate the effects of light treatments on the growth morphology and chemical constituents of Mesembryanthemum crystallinum L. plants, red (R), blue (B), far red (Fr), and white (W) light-emitting diodes (LEDs) were configured to provide different combinations of light spectra and photosynthetic photon flux densities (PPFDs). In Expt. 1, five light spectra of red/white (RW), red/white/far red (RWFr), red/white/high-intensity far red (RWFrD), red/blue (RB), and red/blue/far red (RBFr) were set up in two 3-layered racks with circulating hydroponic systems. In each light spectrum treatment, the distance between the LED lamps and the transplanting board was regulated to provide low PPFD and high PPFD treatments. In Expt. 2, the effect of Fr was further investigated in plants in the early and late growth stages. RWFr light was modified by covering the Fr lamps to become red/white without far red (RW−Fr) light during the early growth stage, and then removing the covers to provide the Fr spectrum red/white with far red (RW+Fr) during the later growth stage. This study suggested that high PPFD was not beneficial for promoting plant growth in any light spectrum treatment. Among light spectrum treatments at a PPFD of 215 ± 15 μmol·m−2·s−1, RW light produced higher vegetative growth. In the late growth stage, RW and RB combined with Fr light promoted reproductive growth, antioxidant activities, and secondary compounds, such as phenolic compounds, pinitol accumulation, and betacyanins. Therefore, RW (227 μmol·m−2·s−1), RW−Fr (162 μmol·m−2·s−1), and RB (162 μmol·m−2·s−1) are suggested for the early growth stage to promote vegetative growth. Then additional Fr light can be applied in addition to RW for secondary metabolite induction in the late growth stage.

scholarly journals Exploitation of variability for salinity tolerance in maize hybrids (Zea mays L.) at early growth stage

2016 ◽  
Vol 11 (42) ◽  
pp. 4206-4213 ◽  
Author(s):  
Qayyum Abdul ◽  
Muhammad Saeed Hafiz ◽  
Hanif Mamoona ◽  
Noor Etrat ◽  
Malik Waqas ◽  
...  
Keyword(s):  
Zea Mays ◽  
Salinity Tolerance ◽  
Growth Stage ◽  
Zea Mays L ◽  
Early Growth ◽  
Early Growth Stage ◽  
Maize Hybrids

Melanosclerites: first North American report of these problematic microfossils and discussion of their affinity

1992 ◽  
Vol 66 (4) ◽  
pp. 563-569 ◽  
Author(s):  
P. B. Cashman
Keyword(s):  
North American ◽  
Growth Stage ◽  
Early Growth ◽  
Junior Synonym ◽  
Early Growth Stage ◽  
The Family ◽  
Strong Resemblance ◽  
Gaspe Peninsula ◽  
Gaspé Peninsula

Melanosclerites are rod-shaped, pseudochitinous microfossils of problematic affinity. They have not been widely studied. The first North American discovery of melanosclerites is here reported; Melanostylus coronifer and Melanosteus acutus (the latter with two subspecies), of Devonian (Late Siegenian) age, were discovered in the Indian Cove Formation of the Upper Gaspé Limestones from the Gaspé Peninsula, Quebec, Canada.These melanosclerites bear a strong resemblance to the modern cubomedusa polyp Carybdea alata and the planula stages of the hydrozoan Pennaria tiarella. They are interpreted as being the embryonic planula and early polyp stages of scyphozoans, cubozoans, and hydrozoans.Consequently, Semenola semen Schallreuter, 1981, is considered an early growth stage of M. acutus anceps and thus a junior synonym; similarly, Eichbaumia incus is a junior synonym of Melanostylus coronifer; while, on the basis of their three-fold symmetry, Orthopelta? femuralis Eller, 1945, and Menola os Schallreuter, 1981, are treated as junior synonyms of Melanofurca neptuni Eisenack, 1963. Melanosclerites could represent the planula and polyp stages of any of the three classes of Cnidaria; therefore, the order Melanoscleritoitidea Eisenack, 1963, and the family Melanoscleritoitidae are here rejected because the supposed family crosses the boundaries of classes. The new subspecific combinations Melanosteus acutus acutus, M. acutus filiformis, and M. acutus anceps are proposed, their diagnoses being emended; the diagnosis of Melanostylus coronifer is also emended.Melanosclerites appear to be strongly facies controlled and thus may have potential for paleoenvironmental and paleogeographical reconstructions.

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