Performance of Maize-Soybean Intercropping under Various N Application Rates and Soil Moisture Conditions in Northern Mozambique

The movement and persistence of 4-amino-3,5,6-trichloropicolinic acid (picloram) in an Osborne clay soil was determined over a 4-year period. Picloram concentrations were determined with soybean(Glycine max(L.) Merr. ‘Altona’) as the bioassay plant. Application rates ranged from 35 to 700 g/ha. Movement and dissipation of picloram were neglible under low soil moisture conditions, but under high rainfall conditions picloram was leached into the 30 to 60-cm depth. A greater percent of the picloram was leached at the higher application rates. Dissipation increased with temperature (days over 27 C) and decreased with increasing depth in the soil profile. Two applications of picloram at 70 g/ha applied in 2 successive years showed no detectable accumulation, but accumulation occurred from two applications of 350 g/ha; 32% of the activity remained after approximately 2 years.

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The Effect of Giant Foxtail (Setaria faberi) Plant Height on Control with Six Postemergence Herbicides

Weed Technology ◽

10.1017/s0890037x00027937 ◽

1993 ◽

Vol 7 (2) ◽

pp. 491-494 ◽

Cited By ~ 4

Author(s):

Ronald F. Krausz ◽

George Kapusta ◽

Joseph L. Matthews

Keyword(s):

Soil Moisture ◽

Plant Height ◽

Field Experiments ◽

Soybean Seed ◽

Herbicide Application ◽

Setaria Faberi ◽

Giant Foxtail ◽

Application Rates ◽

Moisture Conditions ◽

Postemergence Herbicides

Field experiments were conducted from 1986 to 1988 to evaluate giant foxtail control at four plant heights by six POST grass herbicides. Clethodim, fenoxaprop, fluazifop-P, haloxyfop, quizalofop, and sethoxydim controlled 95% or more of 60-cm giant foxtail all three years at the labeled herbicide application rates. Control of 7-, 15-, and 30-cm giant foxtail with fenoxaprop, fluazifop-P, quizalofop, and sethoxydim was dependent upon soil moisture conditions at application. Clethodim and haloxyfop provided the greatest control (89 to 99%) regardless of plant height or soil moisture conditions. No herbicide injured soybean. Soybean seed yield with POST grass herbicides was equal to or greater than yield in the hand-weeded plots.

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Water-level measurements in an observation well found to be useful in determining soil-moisture conditions

Open-File Report ◽

10.3133/ofr4965 ◽

1949 ◽

Author(s):

P.E. Dennis

Keyword(s):

Soil Moisture ◽

Water Level ◽

Observation Well ◽

Moisture Conditions ◽

Water Level Measurements

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Effects of Supplemental Irrigation on Water Consumption Characteristics, Grain Yield and Water Use Efficiency in Winter Wheat under Different Soil Moisture Conditions at Seeding Stage

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1006.2017.01357 ◽

2017 ◽

Vol 43 (9) ◽

pp. 1357 ◽

Cited By ~ 3

Author(s):

Xiang LIN ◽

Dong WANG

Keyword(s):

Soil Moisture ◽

Winter Wheat ◽

Grain Yield ◽

Water Use Efficiency ◽

Water Use ◽

Water Consumption ◽

Supplemental Irrigation ◽

Use Efficiency ◽

Moisture Conditions

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Evaluation of Presswheels and Seed Coverers for Direct Seeding of Brassica

HortScience ◽

10.21273/hortsci.32.4.599e ◽

1997 ◽

Vol 32 (4) ◽

pp. 599E-600

Author(s):

Regina P. Bracy ◽

Richard L. Parish

Keyword(s):

Soil Moisture ◽

Sandy Loam ◽

Visual Observation ◽

Mustard Seed ◽

High Soil Moisture ◽

Loam Soil ◽

Direct Seeded ◽

Plant Emergence ◽

Moisture Conditions ◽

Determine Effect

Improved stand establishment of direct-seeded crops has usually involved seed treatment and/or seed covers. Planters have been evaluated for seed/plant spacing uniformity, singulation, furrow openers, and presswheel design; however, effects of presswheels and seed coverers on plant establishment have not been widely investigated. Five experiments were conducted in a fine sandy loam soil to determine effect of presswheels and seed coverers on emergence of direct-seeded cabbage and mustard. Seed were planted with Stanhay 870 seeder equipped with one of four presswheels and seed coverers. Presswheels included smooth, mesh, concave split, and flat split types. Seed coverers included standard drag, light drag, paired knives, and no coverer. Soil moisture at planting ranged from 8% to 19% in the top 5 cm of bed. Differences in plant counts taken 2 weeks after planting were minimal with any presswheel or seed coverer. Visual observation indicated the seed furrow was more completely closed with the knife coverer in high soil moisture conditions. All tests received at least 14 mm of precipitation within 6 days from planting, which may account for lack of differences in plant emergence.

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INFLUENCE OF THE SYSTEM OF RICE INTENSIFICATION ON RICE YIELD AND NITROGEN AND WATER USE EFFICIENCY WITH DIFFERENT N APPLICATION RATES

Experimental Agriculture ◽

10.1017/s0014479709007583 ◽

2009 ◽

Vol 45 (3) ◽

pp. 275-286 ◽

Cited By ~ 70

Author(s):

LIMEI ZHAO ◽

LIANGHUAN WU ◽

YONGSHAN LI ◽

XINGHUA LU ◽

DEFENG ZHU ◽

...

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

N Use Efficiency ◽

System Of Rice Intensification ◽

N Application ◽

Application Rates ◽

Rice Intensification ◽

Use Efficiency ◽

N Rates ◽

N Use

SUMMARYField experiments were conducted in 2005 and 2006 to investigate the impacts of alternative rice cultivation systems on grain yield, water productivity, N uptake and N use efficiency (ANUE, agronomic N use efficiency; PFP, partial factor productivity of applied N). The trials compared the practices used with the system of rice intensification (SRI) and traditional flooding (TF). The effects of different N application rates (0, 80, 160 and 240 kg ha−1) and of N rates interacting with the cultivation system were also evaluated. Resulting grain yields with SRI ranged from 5.6 to 7.3 t ha−1, and from 4.1 to 6.4 t ha−1 under TF management. On average, grain yields under SRI were 21% higher in 2005 and 22% higher in 2006 than with TF. Compared with TF, SRI plots had higher harvest index across four fertilizer N rates in both years. However, there was no significance difference in above-ground biomass between two cultivation systems in either year. ANUE was increased significantly under SRI at 80 kg N ha−1 compared with TF, while at higher N application rates, ANUE with SRI was significantly lower than TF. Compared with TF, PFP under SRI was higher across all four N rates in both years, although the difference at 240 kg N ha−1 was not significant. As N rate increased, the ANUE and PFP under both SRI and TF significantly decreased. Reduction in irrigation water use with SRI was 40% in 2005 and 47% in 2006, and water use efficiency, both total and from irrigation, were significantly increased compared to TF. With both SRI and TF, the highest N application was associated with decreases in grain yield, N use efficiency and water use efficiency. This is an important finding given current debates whether N application rates in China are above the optimum, especially considering consequences for soil and water resources. Cultivation system, N rates and their interactions all produced significant differences in this study. Results confirmed that optimizing fertilizer N application rates under SRI is important to increase yield, N use efficiency and water use efficiency.

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Influence of atmospheric and soil moisture conditions on diurnal variations in relative turgidity of potato leaves

American Potato Journal ◽

10.1007/bf02877140 ◽

1956 ◽

Vol 33 (9) ◽

pp. 285-285

Author(s):

H. O. Werner

Keyword(s):

Soil Moisture ◽

Diurnal Variations ◽

Moisture Conditions

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Nitrogen management strategies on plant growth and severities of Sclerotinia stem rot of canola in eastern Canada

Canadian Journal of Plant Science ◽

10.1139/cjps-2021-0160 ◽

2021 ◽

Author(s):

Fen Gao ◽

Yuanhong Chen ◽

SeaRa Lim ◽

Allen Xue ◽

Bao-Luo Ma

Keyword(s):

Plant Growth ◽

Seed Yield ◽

Management Strategies ◽

Stem Rot ◽

Sclerotinia Stem Rot ◽

Split Application ◽

Eastern Canada ◽

N Application ◽

Application Rates ◽

N Management

Effective nitrogen (N) management strategies are important for ensuring a balance between optimizing plant growth and minimizing disease damage. A field experiment was conducted for three years to (i) assess the effects of N fertilizer application on the growth and seed yield of canola, and severities of Sclerotinia stem rot (SSR), and (ii) determine a reasonable N-rate for optimizing plant growth and minimizing the loss from SSR in eastern Canada. The experiment was designed with factorial combinations of eight N treatments and two canola hybrids. All N-treatments reduced canola emergence with increasing preplant N application rates above 100 kg ha–1, but had a positive impact on plant height, fresh weight, dry weight and seed yield. The development of SSR showed differential responses to N application rates. Of all the treatments, the split application (50 kg N ha–1 at preplant plus 100 kg N ha–1 side-dressed at the 6-leaf stage) increased canola growth, and often produced the highest or similar seed yields to those of equivalent N rate applied as preplant. At the 150 kg ha–1 N rate, no severe development of SSR was observed in either preplant-only or split application. Overall, this study demonstrates that the split-N management strategy (50+100 kg ha–1) maintained a balance between enhancing plant growth and mitigating the negative impacts of SSR on canola.

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Exploring the potential of soil moisture reanalysis data for improving the identification of regional landslide triggering thresholds

10.5194/egusphere-egu21-2243 ◽

2021 ◽

Author(s):

Nunziarita Palazzolo ◽

David J. Peres ◽

Enrico Creaco ◽

Antonino Cancelliere

Keyword(s):

Soil Moisture ◽

Rainfall Event ◽

Rainfall Thresholds ◽

Rainfall Duration ◽

Soil Moisture Data ◽

Initial Soil Moisture ◽

Initial Soil ◽

Different Depths ◽

Moisture Conditions ◽

Landslide Triggering

<p>Landslide triggering thresholds provide the rainfall conditions that are likely to trigger landslides, therefore their derivation is key for prediction purposes. Different variables can be considered for the identification of thresholds, which commonly are in the form of a power-law relationship linking rainfall event duration and intensity or cumulated event rainfall. The assessment of such rainfall thresholds generally neglects initial soil moisture conditions at each rainfall event, which are indeed a predisposing factor that can be crucial for the proper definition of the triggering scenario. Thus, more studies are needed to understand whether and the extent to which the integration of the initial soil moisture conditions with rainfall thresholds could improve the conventional precipitation-based approach. Although soil moisture data availability has hindered such type of studies, yet now this information is increasingly becoming available at the large scale, for instance as an output of meteorological reanalysis initiatives. In particular, in this study, we focus on the use of the ERA5-Land reanalysis soil moisture dataset. Climate reanalysis combines past observations with models in order to generate consistent time series and the ERA5-Land data actually provides the volume of water in soil layer at different depths and at global scale. Era5-Land project is, indeed, a global dataset at 9 km horizontal resolution in which atmospheric data are at an hourly scale from 1981 to present. Volumetric soil water data are available at four depths ranging from the surface level to 289 cm, namely 0-7 cm, 7-28 cm, 28-100 cm, and 100-289 cm. After collecting the rainfall and soil moisture data at the desired spatio-temporal resolution, together with the target data discriminating landslide and no-landslide events, we develop automatic triggering/non-triggering classifiers and test their performances via confusion matrix statistics. In particular, we compare the performances associated with the following set of precursors: a) event rainfall duration and depth (traditional approach), b) initial soil moisture at several soil depths, and c) event rainfall duration and depth and initial soil moisture at different depths. The approach is applied to the Oltrep&#242; Pavese region (northern Italy), for which the historical observed landslides have been provided by the IFFI project (Italian landslides inventory). Results show that soil moisture may allow an improvement in the performances of the classifier, but that the quality of the landslide inventory is crucial.</p>

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