Preemergence Control of Spotted Spurge (Chamaesyce maculata) with Flumioxazin as Influenced by Formulation and Activation Moisture

2015 ◽  
Vol 29 (1) ◽  
pp. 108-114 ◽  
Author(s):  
Glenn Wehtje ◽  
Q. Yang ◽  
Charles H. Gilliam ◽  
Anna-Marie Murphy ◽  
Jason Fausey
Keyword(s):  
Survival Data ◽  
Seedling Survival ◽  
Separation Distance ◽  
Irrigation Level ◽  
Time Of Application ◽  
Nursery Production ◽  
Excellent Control ◽  
Substrate Moisture ◽  
The Relationship ◽  
Maximum Separation

Flumioxazin is commonly used in nursery production for PRE weed control. Container nursery producers are of the opinion that the granular formulation is less effective than the sprayable formulation. Under the hypothesis that the granular formulation may require more water for activation, an experiment was conducted to evaluate the interaction of flumioxazin formulation, rate, and activation moisture for PRE control of spotted spurge in a pine-bark substrate. Experiment consisted of a factorial arrangement of four experimental variables; flumioxazin formulation (granular and spray), and flumioxazin rate (0.28 and 0.42 kg ai ha−1), substrate moisture level at the time of application (dry, medium, and wet), and after-application irrigation level (a single irrigation at 0.6, 1.3, 2.5, and 5.1 cm). Treated pots were seeded with spotted spurge 2 d after the herbicide application, which was 1 d after the first irrigation. Control as indicated by spotted spurge counts and fresh weight was influenced only by flumioxazin rate and formulation. The sprayable formulation provided excellent control regardless of rate. Granular formulation was generally less effective, and additional activation moisture did not improve efficacy. Further studies were conducted with the granular formulation to determine the maximum separation distance between the spotted spurge seed and herbicide prills at which control is possible. Individual prills and spotted spurge seeds were placed on media surface at progressively increasing separation distances. Nonlinear regression of seedling survival data revealed that ≥99% control required a prill–seed separation of ≤5.2 mm. This prill–seed separation requirement is only marginally obtained with the current registered rate, i.e., 0.42 kg ai ha−1 or 168 kg product ha−1. The relationship between control and prill–seed separation distance cannot be manipulated by additional activation moisture. Inadequate contact between the spotted spurge seeds and the flumoioxazin-containing prills is likely the sole cause of inadequate control.

scholarly journals Optimizing Grain Yield and Water Use Efficiency Based on the Relationship between Leaf Area Index and Evapotranspiration

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 313
Author(s):  
Guoqiang Zhang ◽  
Bo Ming ◽  
Dongping Shen ◽  
Ruizhi Xie ◽  
Peng Hou ◽  
...  
Keyword(s):  
Grain Yield ◽  
Water Use Efficiency ◽  
Leaf Area Index ◽  
Water Use ◽  
Plant Density ◽  
Maize Yield ◽  
Area Index ◽  
Irrigation Level ◽  
Use Efficiency ◽  
The Relationship

Achieving optimal balance between maize yield and water use efficiency is an important challenge for irrigation maize production in arid areas. In this study, we conducted an experiment in Xinjiang China in 2016 and 2017 to quantify the response of maize yield and water use to plant density and irrigation schedules. The treatments included four irrigation levels: 360 (W1), 480 (W2), 600 (W3), and 720 mm (W4), and five plant densities: 7.5 (D1), 9.0 (D2), 10.5 (D3), 12.0 (D4), and 13.5 plants m−2 (D5). The results showed that increasing the plant density and the irrigation level could both significantly increase the leaf area index (LAI). However, LAI expansion significantly increased evapotranspiration (ETa) under irrigation. The combination of irrigation level 600 mm (W3) and plant density 12.0 plants m−2 (D4) produced the highest maize yield (21.0–21.2 t ha−1), ETa (784.1–797.8 mm), and water use efficiency (WUE) (2.64–2.70 kg m−3), with an LAI of 8.5–8.7 at the silking stage. The relationship between LAI and grain yield and evapotranspiration were quantified, and, based on this, the relationship between water use and maize productivity was analyzed. Moreover, the optimal LAI was established to determine the reasonable irrigation level and coordinate the relationship between the increase in grain yield and the decrease in water use efficiency.

scholarly journals Junglerice (Echinochloa colona) Control with Sequential Applications of Glyphosate and Clethodim to Dicamba

2021 ◽  
pp. 1-18
Author(s):  
Clay M. Perkins ◽  
Thomas C. Mueller ◽  
Lawrence E. Steckel
Keyword(s):  
Glyphosate Resistance ◽  
Time Of Application ◽  
Crop Fields ◽  
Row Crop ◽  
Excellent Control ◽  
Sequential Treatments

Abstract Junglerice is becoming more prevalent in Tennessee, Arkansas and Mississippi row crop fields. The evolution of glyphosate-resistant junglerice populations is one reason for the increase. Another possible explanation is that glyphosate and clethodim grass activity is being antagonized by dicamba. This question has led to research to examine if sequential applications alleviate antagonism observed with dicamba plus glyphosate and/or clethodim mixtures and determine if 24 h, 72 h or 168 h sequential treatments of those herbicides can improve junglerice control. Glyphosate + clethodim applications provided >90% junglerice control. The observed levels of antagonism varied by whether the location of the test was in the greenhouse or the field and the timing of applications. In the greenhouse, clethodim + dicamba provided excellent control while in the field the same treatment showed over a 30% reduction in junglerice control compared with clethodim alone. However, control was restored by using a mixture of glyphosate + clethodim without dicamba. The environment at the time of application and relative glyphosate-resistance (GR) level of the junglerice influenced the overall control of these sequential applications. Clethodim applied first followed by dicamba at 72 or 168 h, better control was observed compared with applying dicamba followed by clethodim. Overall, mixing glyphosate + clethodim provided the most complete junglerice control regardless of timing. These data confirm that leaving dicamba out of the spray tank will mitigate herbicide antagonism on junglerice control. These data would also indicate that avoiding dicamba and glyphosate mixtures will also improve the consistency of control with glyphosate-susceptible junglerice.

scholarly journals Carbohydrates on the growth of Cattleya schilleriana Reichb.f. seedlings (Orchidaceae)

2018 ◽  
Vol 48 (7) ◽  
Author(s):  
Renato Fernandes Galdiano Júnior ◽  
Cibele Mantovani ◽  
Eliana Gertrudes de Macedo Lemos
Keyword(s):  
Survival Data ◽  
Culture Medium ◽  
Seedling Survival ◽  
In Vitro Growth ◽  
Growth Data ◽  
Carbohydrate Source ◽  
Carbohydrate Supplementation ◽  
Percentage Survival ◽  
Half Strength

ABSTRACT: The aim of the present study was to evaluate the effects of carbohydrate supplementation on the propagation of the orchid Cattleya schilleriana. The 120-d-old seedlings were subcultured in fructose-, glucose-, or sucrose-supplemented (0, 15, 30, and 45g L-1) ½ MS culture medium (half-strength macronutrient concentrations), using a completely random design with four repetitions per treatment. After 120d of treatment, root number and length, leaf number and length, and fresh weight were evaluated, and seedling survival was evaluated after 75d of acclimatization in a greenhouse. The in vitro growth data were submitted to regression analysis, whereas the percentage survival data were analyzed using ANOVA and Tukey’s test. Both in vitro growth and ex vitro survival were lowest when the plantlets were grown in the absence of a carbohydrate source and highest (>90% survival) when supplemented with glucose. According to our findings, the addition of either glucose (30g L-1) or sucrose (30g L-1) is recommended for mass propagation of C. schilleriana.

scholarly journals Optical Conveyor Belts for Chiral Discrimination: Influence of De-Phasing Parameter

2019 ◽  
Vol 9 (7) ◽  
pp. 1304
Author(s):  
Luis Carretero ◽  
Pablo Acebal ◽  
Salvador Blaya
Keyword(s):  
Numerical Analysis ◽  
Gaussian Beam ◽  
Enantiomeric Separation ◽  
Conveyor Belt ◽  
Separation Distance ◽  
Chiral Discrimination ◽  
Optimum Range ◽  
Conveyor Belts ◽  
Range Of Values ◽  
Maximum Separation

A numerical analysis is carried out of the influence of the de-phasing parameter of anoptical conveyor belt in the enantiomeric separation. The optical conveyor belt is obtained by theinterference of a Laguerre Gaussian and a Gaussian beam with different beam waists, which aretemporally de-phased. In order to obtain the maximum separation distance between enantiomers,we calculate the optimum range of values of the de-phasing parameter.

scholarly journals Integrated analysis identifies AQP9 correlates with immune infiltration and acts as a prognosticator in multiple cancers

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Xiaohong Liu ◽  
Qian Xu ◽  
Zijing Li ◽  
Bin Xiong
Keyword(s):  
Survival Data ◽  
Integrated Analysis ◽  
Immune Gene ◽  
Gene Markers ◽  
Lung Cancers ◽  
Immune Infiltration ◽  
Kaplan Meier ◽  
Aquaporin 9 ◽  
Infiltrating Cells ◽  
The Relationship

AbstractAquaporin 9 (AQP9), as an aquaglyceroporin, is expressed in many immune cells and plays important role in tumor initiation and progression. However, the relationship between AQP9 and tumor-infiltrating cells, and its prognostic value in cancers still require comprehensive understanding. Herein, we aimed to elucidate the correlations of AQP9 with prognosis and immune infiltration levels in diverse cancers. We detected the expression and survival data of AQP9 through Oncomine, TIMER, Kaplan–Meier Plotter and PrognoScan databases. The correlations between AQP9 and immune infiltrates were analyzed in TIMER database. Our results found that high AQP9 expression was significantly correlated with worse prognosis in breast, colon and lung cancers, while predicted better prognosis in gastric cancer. Moreover, AQP9 had significant association with various immune infiltrating cells including CD8+ and CD4+ T cells, neutrophils, macrophages and dendritic cells (DCs), and diverse immune gene markers in BRCA, COAD, LUAD, LUSC and STAD. AQP9 was also significantly correlated with the regulation of tumor associated macrophages (TAM). These results indicate that AQP9 can play as a significant biomarker to determine the prognosis and the immune infiltrating levels in different cancers. It might also contribute to the development of the immunotherapy in breast, colon, lung and gastric cancers.

Hexazinone Gridballs™ applied with concurrent underplanting of white spruce in boreal mixedwoods: 7-year results

1986 ◽  
Vol 62 (4) ◽  
pp. 226-232 ◽  
Author(s):  
R. F. Sutton
Keyword(s):  
Picea Glauca ◽  
Ground Surface ◽  
White Spruce ◽  
Separation Distance ◽  
Stem Volume ◽  
Weed Growth ◽  
M 10 ◽  
The Mean ◽  
Boreal Mixedwoods ◽  
Maximum Separation

In mid-June 1978, hexazinone Gridball™ pellets were individually placed on the ground surface in two10-m × 10-m plots at each of two grid spacings in moderate-to-dense, woody weed growth in each of three boreal mixedwood stands in the Chapleau and Manitouwadge areas of Ontario. The rates of application were equivalent to 0.0, 1.4 and 4.2 kg a.i./ha. In these and a similar number of untreated plots, 16 white spruce (Picea glauca [Moench] Voss) were planted centrally in each plot at the same grid spacings used for the Gridballs™ but offset so as to give maximum separation between outplants and herbicide. The main study was supplemented by another to determine safe separation distance. GridballsTM at close spacing very significantly (P 0.01) increased growth of white spruce: at one location, the mean stem volume of spruce 7 years after planting was 438% that of spruce in the no-herbicide treatment; at a second location the comparable value was 503%. The evidence suggests that white spruce may be established in the boreal mixedwoods by underplanting and, concurrently, applying Gridballs™ at 1-m × 1-m spacing.

scholarly journals Myxospermous seed-mucilage quantity correlates with environmental gradients indicative of water-deficit stress: Plantago species as a model

2019 ◽  
Vol 446 (1-2) ◽  
pp. 343-356 ◽  
Author(s):  
António Teixeira ◽  
Pietro Iannetta ◽  
Kirsty Binnie ◽  
Tracy A. Valentine ◽  
Peter Toorop
Keyword(s):  
Seed Germination ◽  
Water Deficit ◽  
Stress Responses ◽  
Environmental Gradients ◽  
Seedling Survival ◽  
Water Deficit Stress ◽  
Arid Environments ◽  
Seedling Mortality ◽  
The Relationship ◽  
Seed Mucilage

Abstract Aims Myxospermous seed mucilage is multifunctional and is often found in seeds (or achenes) of species occupying arid environments where the trait may influence seed-dispersal and -germination of seeds. The seed mucilage may also enhance soil-water retention, −hydraulic conductivity and -stability. However, the relationship between seed mucilage quantity, seed germination and seedling traits across environmental gradients which determine water-deficit stress has not yet been ascertained. Methods Therefore, we characterised and tested the relationship between seed mucilage quantity, water-deficit stress responses of seeds and seedlings of 36 accessions of four different Plantago species (P. albicans L., P. coronopus L., P. lagopus L. and P. anceolata L.). These were gathered from six regions across Europe, which presented environmental gradients (of rainfall and temperature), and varying soil qualities. Results Seed mucilage was significantly greater in seeds of accessions experiencing: highest summer temperatures; lowest summer precipitation; soils of the same warm dry regions which had greater capacity to retain water within narrow pore spaces. Under water-deficit stress, seeds with most mucilage exhibited a lower base water potential for germination, suffered least seedling mortality and exhibited the most successful seedling development. Conclusions The findings indicate that seed mucilage quantity appeared as an ‘adaptive’ trait and there is a relationship between seed-mucilage quantity, seed germination plus seedling survival and development under environmental conditions of highest water-deficit stress.

Biotic and abiotic drivers of dipterocarp seedling survival following mast fruiting in Malaysian Borneo

2014 ◽  
Vol 31 (2) ◽  
pp. 129-137 ◽  
Author(s):  
Chiaki Oshima ◽  
Yuji Tokumoto ◽  
Michiko Nakagawa
Keyword(s):  
Survival Data ◽  
Species Coexistence ◽  
Seedling Survival ◽  
Abiotic Factors ◽  
Canopy Openness ◽  
Relative Importance ◽  
Tropical Rain Forests ◽  
Seedling Density ◽  
Mast Fruiting ◽  
General Flowering

Abstract:South-East Asian tropical rain forests experience sporadic, but profuse, seed production after general flowering, leading to the synchronous emergence of various seedlings and subsequent seedling dynamics, which play a crucial role in determining species distribution and coexistence. We examined the relative importance of both biotic (initial height, conspecific seedling density) and abiotic (canopy openness, per cent sand, soil water content) drivers using survival data for 1842 seedlings of 12 dipterocarp species for 1.5 y following mast fruiting in an old-growth Bornean tropical rain forest. More than 30% of all dipterocarp seedlings survived 1.5 y after mast fruiting. When all species were analysed together, we found that initial seedling height, canopy openness and conspecific seedling density affected dipterocarp seedling survival. Negative density dependence indicated that predators were not satiated, but dipterocarp seedlings rather suffered from host-specific natural enemies or intraspecific competition. Species-level analyses of seven dipterocarp species showed large variation in response to biotic and abiotic factors. These results suggest that interspecific differences in the relative importance of biotic and abiotic effects on seedling survival might contribute to species coexistence.

The role of surgery in the management of supratentorial intermediate and high-grade astrocytomas in adults

1990 ◽  
Vol 73 (3) ◽  
pp. 331-344 ◽  
Author(s):  
Jules M. Nazzaro ◽  
Edward A. Neuwelt
Keyword(s):  
Surgical Management ◽  
Survival Data ◽  
Postoperative Radiotherapy ◽  
High Grade ◽  
Survival Times ◽  
Term Survival ◽  
Content Type ◽  
The Relationship

✓ In this analysis, the authors review studies over the last 50 years addressing the association between long-term survival and type of surgical management in adults with supratentorial intermediate or high-grade astrocytomas. Earlier reports are included because they are repeatedly referenced in current works and clearly are an important basis upon which present attitudes are predicated. Because recent work has definitively demonstrated the significance of prognostic variables on outcome, the handling of such factors in studies that investigated survival data according to degree of surgery is emphasized. Study design, experimental methods used, and methods of data analysis are also examined. This analysis shows that there is little justification for dogmatic statements concerning the relationship between increasing patient survival times and aggressive surgical management in adults with supratentorial intermediate or high-grade astrocytomas, if patients receive postoperative radiotherapy.

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