CHEMICAL CONTROL OF THE NARCISSUS BULB FLY, LAMPETIA EQUESTRIS (F.), IN BRITISH COLUMBIA

1959 ◽  
Vol 39 (1) ◽  
pp. 56-62 ◽  
Author(s):  
H. Andison ◽  
W. T. Cram

The narcissus bulb fly, Lampetia equestris (F.), was controlled on southern Vancouver Island with insecticides applied by four methods at planting time to narcissus bulbs grown in sandy loam soils of pH 5.9 to 6.5.Soaking bulbs for 1.5 hours in hot-water (110° F.) and formalin mixture as for control of the bulb nematode, with heptachlor emulsifiable concentrate added at 2, 4, or 10 lb. of toxicant per 1,000 gal. gave 100 per cent control for the 2 years tested. Soaking the bulbs for 10 minutes in cold water containing emulsifiable concentrates of dieldrin or heptachlor at 3 lb. of toxicant per 100 gal., or of aldrin or chlordane at 5 lb., gave 93 to 98.5 per cent control for 3 years; DDT at 5 lb. and lindane at 0.5 lb. were not effective. A dust of dieldrin at 3 lb. of toxicant per acre, of aldrin or heptachlor at 5 lb., or of chlordane 10 lb. applied to the bulbs in the open furrow gave 95 to 99 per cent control for 3 years; lindane at 1 lb. did not give satisfactory control. A spray containing an emulsifiable concentrate of dieldrin at 1 lb. of toxicant per 100 gal. per acre, of aldrin or heptachlor at 2 lb., or of chlordane at 5 lb. gave 91 to 96 per cent control for the 2 years tested. The soil in this test had the highest organic matter content (13 per cent); the others were moderately high with 5 to 8 per cent. Lindane in the cold-water soak treatment was the only insecticide that adversely affected bulb growth.

1976 ◽  
Vol 56 (3) ◽  
pp. 129-138 ◽  
Author(s):  
A. J. MACLEAN

The Cd concentration in 10 plant species grown in a neutral surface soil (0.65 ppm Cd) varied from 0.18 ppm in potato tubers to 0.99 ppm in soybean roots on a dry matter basis. Addition of 5 ppm Cd increased the concentrations in the plants markedly and they were particularly high in lettuce (10.36 ppm) and tobacco leaves (11.57 ppm). Cd concentrations tended to be lower in the edible portion (seed, fruit, tubers) than in other plant parts. Added Cd affected yields in only a few instances. But in another experiment, Cd added at a rate of 5 ppm to five soils decreased the yield of lettuce in most instances. In a comparison of results for two similarly managed sandy loam soils, nearly neutral in reaction but differing in organic matter content (2.17 vs. 15.95% organic C), the concentration of Cd was lower in lettuce grown in the soil with the higher amount of organic matter. The Cd content of the lettuce was reduced by liming some of the acid soils. Addition of Cd increased the concentration of Zn in the plants appreciably, but added Zn did not affect Cd uptake. In an incubation experiment comprising five soils, DTPA (diethylenetriamine-pentaacetic acid) extractable Cd decreased with liming of three Cd-treated acid soil samples. In comparisons of two sandy loam soils and of surface and subsoil layers of a sand, extractable Cd increased with higher amounts of soil organic matter.


1982 ◽  
Vol 62 (1) ◽  
pp. 165-175 ◽  
Author(s):  
C. R. DE KIMPE ◽  
M. BERNIER-CARDOU ◽  
P. JOLICOEUR

Twenty-one topsoils, with texture varying from sandy loam to clay and organic matter content ranging from 1.6 to 11.9%, were submitted to compaction and settling at different moisture contents where dry bulk density was determined. Under compaction, the density curve went through a maximum while a minimum was observed in the case of settling. Optimum moisture contents corresponding to these two characteristic densities were almost the same. The most important physical properties affecting soil behavior under compaction and settling were found to be water retention properties at low matric potential which themselves depended primarily on organic matter content. Samples submitted to compaction had saturated hydraulic conductivities less than 1 cm/h, while after settling, Ksat measurements ranged from 0.8 to 234 cm/h. Organic matter played an important role in reducing the effects of compaction, and moisture content alone was not sufficient to predict the best conditions for workability in the fields.


Soil Research ◽  
2016 ◽  
Vol 54 (7) ◽  
pp. 880
Author(s):  
Mohammad Reza Chaichi ◽  
Marcus Turcios ◽  
Mina Rostamza

Non-ionic surfactants have been well researched as a tool to ameliorate water repellent conditions. However, few studies have evaluated the risks and benefits of non-ionic surfactant applications in wettable soil. The objective of this study was to evaluate the effects of a surfactant in modifying the wetting pattern in soils of different textures and organic matter contents. The experimental treatments consisted of (1) four different soil textures including sandy, sandy loam, sandy clay loam and silt loam, (2) four different organic matter contents (0.2, 0.7, 1.2 and 1.7% by weight), and (3) irrigation water treatments with or without surfactant (IrrigAid Gold). The experiment was carried out in Plexiglas boxes with one drip emitter under the soil surface. The results demonstrated the superiority of surfactant application on increasing water distribution in the soil profile for all soil textural classes. Silt loam texture had the highest side wetted area and wetting depth 45min after the initiation of irrigation. Upward capillary water movement and top wetted area significantly decreased in the surfactant treatment across all soil textures except in sandy soil. As organic matter content increased, top wetted area decreased. These findings clarified the potential ability of surfactant in increasing water infiltration in non-repellent soil in an in vitro system.


1961 ◽  
Vol 7 (4) ◽  
pp. 507-513 ◽  
Author(s):  
E. Strzelczyk

This study represents an attempt to correlate the low numbers of Azotobacter in rhizosphere and root-free soils at the Central Experimental Farm, Ottawa, with the incidence of bacterial and actinomycete antagonists of this organism. Wheat, radish, and onion were grown in the greenhouse in two soils varying greatly in fertility and organic matter content, and isolations of bacteria and actinomycetes were made periodically for testing against Azotobacter. It was found that rhizosphere soil contained greater numbers of microorganisms antagonistic to Azotobacter than root-free soil. Of the three crops used wheat exerted the least effect. In all the tests numbers of antagonists were greater in the fertile Granby sandy loam than in the infertile Upland sand. The results correlated well with the Azotobacter populations in these soils as reported in the first paper of this series.


1966 ◽  
Vol 46 (2) ◽  
pp. 133-138 ◽  
Author(s):  
N. S. Miljkovic ◽  
B. C. Matthews ◽  
M. H. Miller

The available boron content of the genetic horizons of eight Ontario soils was determined using a hot-water extraction and a sunflower test. The available boron was highest in the surface horizons and decreased in the zones of eluviation to a level equal to or lower than that in the parent material. The content in the horizons was generally higher than that in the C horizons.The water-soluble boron was closely related to the organic matter content in a quadratic regression (R2 = 0.691). When pH and clay content were included in regressions, a positive organic matter × pH component was the single most important variable, explaining 64.4% of the variability. Additional terms involving clay content and pH did not greatly increase the R2 value.


Weed Science ◽  
1999 ◽  
Vol 47 (3) ◽  
pp. 349-352 ◽  
Author(s):  
Chris H. Tingle ◽  
David R. Shaw ◽  
Patrick D. Gerard

Laboratory studies were conducted to evaluate14C-flumetsulam mobility in two Mississippi soils of varied texture and organic matter content following delays in irrigation. Mobility was evaluated using packed soil columns, 25 cm deep, under unsaturated–saturated flow conditions. Irrigation timings included 0, 3, and 5 d after flumetsulam application. Flumetsulam mobility (defined as the amount collected in leachate) decreased from 45% to no more than 20% of the applied in the Prentiss sandy loam soil when irrigation was delayed 3 or 5 d. With the Okolona soil, flumetsulam recovery in the leachate was 21, 14, and 6%, respectively when irrigation occurred 0, 3, and 5 d after application. Flumetsulam proved to be mobile when irrigation immediately followed application, with 6 to 45% recovered in the leachate from all soils evaluated. The Prentiss soil retained 6% of the applied flumetsulam in the upper 5 cm and the Okolona soil retained 22% when irrigation immediately followed flumetsulam application. When the irrigation interval was delayed at least 3 d, the Okolona soil retained 40% in the upper 5 cm, whereas the Prentiss soil retained 10%. Flumetsulam mobility was dependent on irrigation timing and soil type.


1980 ◽  
Vol 60 (1) ◽  
pp. 5-11 ◽  
Author(s):  
M. K. PRITCHARD ◽  
E. H. STOBBE

The persistence and phytotoxicity of dinitramine (n4, N4-diethyl-α,α,α-trifluoro-3,5-dinitrotoluene-2,4-diamine), fluchloralin (N-(2-chloroethyl)-2, 6-dinitro- N-propyl-4- (trifluoromethyl)aniline), profluralin (N-(cyclopropylmethyl)α,α,α-trifluoro-2, 6-dinitro-N-propyl-p-toluidine), and trifluralin (α,α,α-trifluoro-2,6-dinitro-N-N-dipropyl-p-toluidine) were compared in three Manitoba soils: sandy loam, clay loam and clay. The phytotoxicities of all chemicals decreased with increased organic matter. The phytotoxicities of the dinitroanilines were: dinitramine > trifluralin > profluralin = fluchloralin. Increased organic matter increased the persistence of trifluralin and fluchloralin. Profluralin and dinitramine persistence increased with increased clay and organic matter content. Profluralin was the most persistent chemical over all soil types. Under environmental conditions that retard dinitroaniline loss from Manitoba soils, residues of some of these herbicides may cause crop injury the year after application.


1990 ◽  
Vol 4 (2) ◽  
pp. 279-283 ◽  
Author(s):  
Michael R. Blumhorst ◽  
Jerome B. Weber ◽  
Len R. Swain

Field experiments were conducted on six loam and sandy loam soils to study the influence of various soil parameters on atrazine, cyanazine, alachlor, metolachlor, and pendimethalin efficacy. Herbicidal activity was highly correlated to the soil organic content. Humic matter content was equally or better correlated (r = 0.70 to 0.91) with herbicide bioactivity than was organic matter content (r = 0.66 to 0.84). Regression equations were determined which allow herbicide rate recommendations for 80% weed control to be calculated based on soil humic matter or organic matter levels.


1992 ◽  
Vol 72 (4) ◽  
pp. 517-526 ◽  
Author(s):  
J. L. Walworth ◽  
M. T. Panciera ◽  
R. G. Gavlak

Field trials were conducted on three cryic soils in southcentral Alaska to determine the local suitability of the Mehlich 3 extractant. Mehlich 3 extractable B, Cu, Fe, Mn and Zn, DTPA-TEA extractable Cu, Fe, Mn and Zn, and hot water extractable B were measured on soils from factorial experiments with variable rates of B, Cu, Mn, and Zn. Additional soil samples from two B rate and liming studies in central Alaska were included in extractable B comparisons. Forage rape, broccoli, and potato tissue samples were collected from the factorial studies to determine relationships between soil- and plant-available micronutrients. Crop yields were not affected by micronutrient applications Neither Mehlich 3 nor DTPA-TEA extractant predicted plant-available Cu or Fe. Coefficients of determination between soil and plant tissue B were comparable for extraction by Mehlich 3 or hot water and ranged from 0.11 to 0.82 Neither the Mn nor Zn tests accounted for more than 39% of the observed tissue nutrient concentration variation. The inclusion of soil PH and organic matter slightly improved estimates of available B, Mn, and Zn. Mehlich 3 extractable Fe was poorly related to DTPA-TEA extractable Fe. Copper extracted with Mehlich 3 was related to that extracted with DTPA-TEA (r2 = 0.73); the inclusion of soil pH improved the relationship (r2 = 0.84). Mehlich 3 extractable Mn and Zn were closely related to DTPA-TEA extractable levels (r2 = 0.91 and 0.94, respectively). The correlation between Mehlich 3 and hot water B (r2 = 0.57) was significantly improved by including soil organic matter content (r2 = 0.71). Key words: Micronutrients, extractant, Mehlich 3, DTPA, hot water


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