Field studies of cadmium in potatoes (Solanum tuberosum L.) I. Effects of lime and phosphorus on cv. Russet Burbank

1993 ◽  
Vol 44 (4) ◽  
pp. 845 ◽  
Author(s):  
LA Sparrow ◽  
AA Salardini ◽  
AC Bishop
Keyword(s):  
Field Experiments ◽  
Solanum Tuberosum L ◽  
Field Studies ◽  
Russet Burbank ◽  
Oxide Content ◽  
Triple Superphosphate ◽  
Ph Change ◽  
P Fertilizer ◽  
Fourth Experiment ◽  
Cd Availability

Field experiments were conducted at three sites on basaltic krasnozems to examine cadmium (Cd) responses of Russet Burbank potatoes to different rates of broadcast lime and banded phosphorus (P). Double superphosphate (DSP, containing 15 and 90 mg Cd kg-1) and triple superphosphate (TSP, 12 mg Cd kg-1)) were the sources of P. In a fourth experiment, lime was banded with the basal fertilizer. Despite producing a range of topsoil pH (1:5 H20) of 5.2 to 7.1, broadcast lime had no effect on tuber Cd concentrations. Lime had no effect when banded with the basal fertilizer, and the practice did not adversely affect yields. With broadcast lime, Cd availability from the fertilizer band may have been unaffected. However, there were also no lime x P interactions at any site, suggesting that lime also had no effect on the availability of Cd in the soil. It is possible that Tasmanian krasnozems, with their high organic matter and iron oxide content, restrict the availability of Cd in the soil such that pH change exerts little net influence on Cd availability. Increasing amounts of Cd applied in P fertilizer increased tuber Cd concentrations significantly, but the increases were less per unit of P than those found previously when TSP with 151 mg Cd kg-1) was used.

Field studies of cadmium in potatoes (Solanum tuberosum L.). Response of cvv. Russet Burbank and Kennebec to two double superphosphates of different cadmium concentration

1993 ◽  
Vol 44 (4) ◽  
pp. 855 ◽  
Author(s):  
LA Sparrow ◽  
AA Salardini ◽  
AC Bishop
Keyword(s):  
Solanum Tuberosum ◽  
Significant Relationship ◽  
Field Experiments ◽  
Solanum Tuberosum L ◽  
Cadmium Concentration ◽  
Field Studies ◽  
Russet Burbank ◽  
Root Proliferation ◽  
High Yields ◽  
Cd Removal

Separate field experiments were conducted with Russet Burbank and Kennebec potatoes on a basaltic krasnozem where tuber cadmium (Cd) responses were examined over three rates of banded phosphorus (P), supplied as double superphosphate (DSP) containing either 15 or 90 mg Cd kg-1. In both cultivars, tuber Cd concentrations increased with rate of DSP. This response was due more to the amount of P supplied in the DSP than the amount of Cd supplied in the DSP and may be a result of banded P encouraging root proliferation in the fertilizer band. Even with DSP at 15 mg Cd kg-1, Cd additions at rates of DSP needed for high yields were 6-20 times higher than corresponding rates of Cd removal in tubers. Examination of data from all studies of Cd in Russet Burbank on Tasmanian krasnozems showed a significant relationship between petiole and tuber Cd concentrations, but the estimation of a petiole concentration associated with the critical tuber Cd concentration in Australia was subject to unacceptable uncertainty due to variation between sites.

Field studies of cadmium in potatoes (Solanum tuberosum L.). III. Response of cv. Russet Burbank to sources of banded potassium

1994 ◽  
Vol 45 (1) ◽  
pp. 243 ◽  
Author(s):  
LA Sparrow ◽  
AA Salardini ◽  
J Johnstone
Keyword(s):  
Field Experiments ◽  
Solanum Tuberosum L ◽  
Field Studies ◽  
Chloride Ions ◽  
Russet Burbank ◽  
Potassium Sulfate ◽  
Fertilizer Treatment ◽  
Cd Uptake ◽  
Sulfate Ions ◽  
Soil Adsorption

Six field experiments were conducted where Russet Burbank potatoes were grown with banded fertilizer consisting of diammonium phosphate (DAP) and either potassium sulfate (K2S04) or potassium chloride (KCl). At each site, rates of nitrogen (N), phosphorus (P) and potassium (K) were matched as closely as possible for each K fertilizer treatment. At four of the six sites, potatoes grown with K2S04 had tuber and petiole cadmium (Cd) concentrations 20-30% lower than did potatoes grown with KCl. The use of K2S04 instead of KCl appears to offer considerable promise as a means of decreasing tuber Cd uptake. Sulfate ions presumably promote increased soil adsorption of soil and/or fertilizer Cd compared with chloride ions, and so decrease Cd availability. We attributed the lack of difference in tuber and petiole Cd between K sources at two sites to either leaching, chloride in irrigation water, or at one site to a higher than desired rate of NPK fertilizer with the sulfate treatment. Any one of these may have offset decreases in Cd uptake due to the presence of sulfate ions.

Comparison of total tuber yields from inner and guard rows used in potato (Solanum tuberosum L.) fertiliser experiments

1991 ◽  
Vol 31 (3) ◽  
pp. 393
Author(s):  
NA Maier ◽  
AB Frensham ◽  
KSR Chapman ◽  
CMJ Williams
Keyword(s):  
Field Experiments ◽  
Tuber Yield ◽  
Solanum Tuberosum L ◽  
Practical Importance ◽  
South Australia ◽  
Russet Burbank ◽  
Standard Errors ◽  
Yield Response ◽  
The Mean ◽  
The Difference

Total tuber yields were compared for inner and outer (guard) rows from 4 phosphorus (P) and 3 nitrogen (N) field experiments conducted during 1985-86 in South Australia, and from 5 N and 2 potassium (K) field experiments conducted during 1985-86 and 1987-88 in Tasmania. All fertiliser treatments were banded along the rows, either at planting or part at planting and the remainder sidedressed after emergence. The inter-row spacings were in the range 76-86 cm and the cultivars used were Kennebec, Coliban and Russet Burbank. Analysis showed that at only 1 of the 14 sites (site 6 in South Australia) was the mean total tuber yield for the inner 2 rows significantly (P<0.01) less than the mean total tuber yield for all 4 rows. However, the difference was small (0.8 t/ha or 1.9%) and of little practical importance. The relationships between mean (� s.e.) total tuber yield and rate (kg/ha) of applied nutrient (0-240 P, 0-320 N, 0-400 K) for inner and guard rows showed that differences between means were small and usually within standard error ranges at all sites. There were no consistent differences in the magnitudes of the standard errors of the means for inner and guard rows for all rates and types of nutrient applied. No significant cross-feeding occurred in these fertiliser experiments, which suggests that omission of guard rows from experiments where the fertiliser treatments are applied along the rows should not result in serious errors of interpretation of tuber yield response.

Response of potatoes (Solanum tuberosum cv. Russet Burbank) to band-placed and broadcast high cadmium phosphorus fertiliser on heavily cropped krasnozems in north-western Tasmania

1992 ◽  
Vol 32 (1) ◽  
pp. 113 ◽  
Author(s):  
LA Sparrow ◽  
KSR Chapman ◽  
D Parsley ◽  
PR Hardman ◽  
B Cullen
Keyword(s):  
Solanum Tuberosum ◽  
Field Experiments ◽  
Solanum Tuberosum L ◽  
Russet Burbank ◽  
Yield Response ◽  
Tuber Size Distribution ◽  
Extractable P ◽  
Phosphorus Fertiliser ◽  
Yield Responses ◽  
North Western

Four field experiments were conducted to examine the yield response and cadmium (Cd) concentration of potatoes (Solanum tuberosum L. cv. Russet Burbank) grown with banded or broadcast phosphorus (P) fertiliser at rates up to 240 kg P/ha. The Cd content of the triple superphosphate (TSP) was 151 mg/kg. All 4 sites were on intensively cropped, high P-fixing krasnozem soils in north-western Tasmania, with concentrations of Colwell-extractable P ranging from 112 to 210 mg/kg. All sites showed economic yield responses to banded P, but broadcast P was much less effective except at the site where the response to banded P was least. Yield responses came mostly through increased tuber number, but at 1 site the tubers were also bigger. There was no effect of P on tuber size distribution or specific gravity. Increasing rates of banded TSP increased tuber Cd concentrations by 50-300% at the 3 sites where they were measured; broadcast TSP had little effect. Tubers from the site with pH 6.0 had much higher Cd concentrations than those from the sites with pH 6.5 and 6.6. Petiole Cd concentrations were about 5 times greater than tuber concentrations.

scholarly journals Evaluating the Impact of Two Generalist Predators on the Leafhopper Erasmoneura vulnerata Population Density

Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 321
Author(s):  
Stefan Cristian Prazaru ◽  
Giulia Zanettin ◽  
Alberto Pozzebon ◽  
Paola Tirello ◽  
Francesco Toffoletto ◽  
...  
Keyword(s):  
Field Experiments ◽  
Field Studies ◽  
Generalist Predators ◽  
Predator Species ◽  
Potted Plants ◽  
Naturally Occurring ◽  
Orius Majusculus ◽  
Limited Effectiveness ◽  
Pest Outbreaks ◽  
The Impact

Outbreaks of the Nearctic leafhopper Erasmoneura vulnerata represent a threat to vinegrowers in Southern Europe, in particular in North-eastern Italy. The pest outbreaks are frequent in organic vineyards because insecticides labeled for organic viticulture show limited effectiveness towards leafhoppers. On the other hand, the naturally occurring predators and parasitoids of E. vulnerata in vineyards are often not able to keep leafhopper densities at acceptable levels for vine-growers. In this study, we evaluated the potential of two generalist, commercially available predators, Chrysoperla carnea and Orius majusculus, in suppressing E. vulnerata. Laboratory and semi-field experiments were carried out to evaluate both species’ predation capacity on E. vulnerata nymphs. The experiments were conducted on grapevine leaves inside Petri dishes (laboratory) and on potted and caged grapevines (semi-field); in both experiments, the leaves or potted plants were infested with E. vulnerata nymphs prior to predator releases. Both predator species exhibited a remarkable voracity and significantly reduced leafhopper densities in laboratory and semi-field experiments. Therefore, field studies were carried out over two growing seasons in two vineyards. We released 4 O. majusculus adults and 30 C. carnea larvae per m2 of canopy. Predator releases in vineyards reduced leafhopper densities by about 30% compared to the control plots. Results obtained in this study showed that the two predators have a potential to suppress the pest density, but more research is required to define appropriate predator–prey release ratios and release timing. Studies on intraguild interactions and competition with naturally occurring predators are also suggested.

scholarly journals The watching eyes effect on charitable donation is boosted by fewer people in the vicinity

2016 ◽  
Vol 7 (2) ◽  
pp. 9-12
Author(s):  
Ryo Oda ◽  
Ryota Ichihashi
Keyword(s):  
Field Study ◽  
Charitable Giving ◽  
Field Experiments ◽  
Field Studies ◽  
Prosocial Behaviors ◽  
Charitable Donation ◽  
Charitable Donations ◽  
Large Groups

Previous field experiments have found that artificial surveillance cues facilitated prosocial behaviors such as charitable donations and littering. Several previous field studies found that the artificial surveillance cue effect was stronger when few individuals were in the vicinity; however, others reported that the effect was stronger in large groups of people. Here, we report the results of a field study examining the effect of an artificial surveillance cue (stylized eyes) on charitable giving. Three collection boxes were placed in different locations around an izakaya (a Japanese-style tavern) for 84 days. The amount donated was counted each experimental day, and the izakaya staff provided the number of patrons who visited each day. We found that the effect of the stylized eyes was more salient when fewer patrons were in the izakaya. Our findings suggest that the effect of the artificial surveillance cue is similar to that of “real” cues and that the effect on charitable giving may weaken when people habituate to being watched by “real” eyes. 

scholarly journals Optimizing Sowing Depth of Tef for Irrigated Mediterranean Conditions: From Laboratory to Field Studies

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1983
Author(s):  
Shiran Ben-Zeev ◽  
Shane Kerzner ◽  
Onn Rabinovitz ◽  
Yehoshua Saranga
Keyword(s):  
Field Experiments ◽  
Field Studies ◽  
Field Trials ◽  
Eragrostis Tef ◽  
Sowing Depth ◽  
New Crops ◽  
Different Depths ◽  
Plant Emergence ◽  
Increasing Demand ◽  
Mediterranean Conditions

Developing new crops adapted to arid conditions is a promising approach to meet the increasing demand for food production under expanding aridity. Tef [Eragrostis tef (Zucc.) Trotter] is a C4 cereal crop cultivated mainly in Ethiopia and the Horn of Africa, and known for its high resilience to stressful environments. Due to their tiny size, tef seeds are traditionally sown by broadcasting and lightly covering with soil. Under semiarid Mediterranean conditions, a deeper sowing may guarantee seedling establishment while saving on irrigation water. The objective of this study was, therefore, to determine the effects of sowing depth on tef emergence, development, lodging, and productivity. Tef seeds were sown at different depths in test tubes and pots, and in two field experiments. In tubes and pots, time from sowing to emergence increased about twofold and emergence rate decreased in the deepest sowing (3 cm) treatment compared to controls (0 cm). In the pot and field trials, deep sowing (3 cm) significantly reduced plant height, shoot and root biomass, and lodging. Sowing depths of 1–2 cm allowed successful plant establishment while not exacting penalties on plant emergence or development; hence this range appears to be optimal for sowing irrigated tef.

The fate of detergent surfactants in sewer systems

1995 ◽  
Vol 31 (7) ◽  
pp. 321-328 ◽  
Author(s):  
E. Matthijs ◽  
G. Debaere ◽  
N. Itrich ◽  
P. Masscheleyn ◽  
A. Rottiers ◽  
...  
Keyword(s):  
Fatty Alcohol ◽  
Half Life ◽  
Laboratory Tests ◽  
Field Experiments ◽  
Sewage Treatment ◽  
Field Studies ◽  
Municipal Sewage ◽  
Alcohol Ethoxylate ◽  
Rapid Reduction ◽  
Laboratory Findings

The fate of detergent surfactants in the sewer can be studied both in laboratory tests and in field experiments. The laboratory studies can be used to determine the rate of disappearance of a test molecule as a function of residence time and estimate its half-life in a given habitat. In addition, important information can be obtained on the mechanism of degradation. Field studies can determine the actual environmental concentrations of surfactants in raw sewage which can then be compared with the expected concentration based on consumption volumes. The difference between the measured and predicted concentration provides an estimate for the disappearance of the test chemical during its travel in the sewer and confirms the results of the laboratory tests. This paper focuses on the fate of a number of important representative anionic, nonionic and cationic surfactants, in the sewer. The results of laboratory die-away studies showed that, in general, the half-life for disappearance in the sewer was in the order of hours for Fatty Alcohol Ethoxylate (AE), Fatty Alcohol Ethoxy Sulphate (AES) and Di-Ethyl-Ester Di-methyl-Ammonium Chloride (DEEDMAC). These laboratory findings for AES were confirmed by monitoring actual raw sewage reaching municipal sewage treatment plants. In addition, a field study demonstrated that the concentration of glucose amides (GA) is considerably reduced during its travel in the sewer. These complementary laboratory and field studies provide key information for the safety assessment of surfactants. They demonstrate that the concentration of surfactants can be significantly reduced in the sewer resulting in a rapid reduction of the environmental loading, which is particularly important in environmental situations where inadequate or no sewage treatment exists.

Foliar and Root Absorption of Atrazine Applied Postemergence to Giant Foxtail

Weed Science ◽  
1969 ◽  
Vol 17 (2) ◽  
pp. 251-256 ◽  
Author(s):  
Lafayette Thompson ◽  
F. W. Slife
Keyword(s):  
Field Experiments ◽  
Soil Surface ◽  
Dry Weight ◽  
Field Studies ◽  
Simulated Rainfall ◽  
Root Absorption ◽  
Giant Foxtail ◽  
Setaria Faberii ◽  
Chamber Studies ◽  
Growth Chamber Studies

In growth chamber studies, high relative humidity and rewetting crystalline spray deposits of 2-chloro-4-ethylamino-6-isopropylamino-s-triazine (atrazine) increased absorption by and phytotoxicity to giant foxtail (Setaria faberii Herrm.), but phytotoxicity was restricted to expanded (unrolled) leaves unless some atrazine was absorbed by the roots. Though phytotoxicity was increased by simulated rainfall when root absorption was prevented, an appreciable number of the plants were killed only when atrazine residues were washed into the soil. In field studies, atrazine applied to a wet soil surface was as effective as the same rate of atrazine foliarly applied. In other field experiments, atrazine applied to giant foxtail on a wet soil and followed by simulated rainfall reduced stand and dry weight, but on a dry soil and not followed by simulated rainfall, atrazine reduced dry weight less and did not reduce stand. These results are due to root absorption of atrazine from wet soil. Spray additives increased phytotoxicity.

scholarly journals Short- and Long-Term Effects of Nonconsciously Processed Ambient Scents in a Servicescape: Findings From Two Field Experiments

2019 ◽  
Vol 22 (4) ◽  
pp. 440-455 ◽  
Author(s):  
Anna Girard ◽  
Marcel Lichters ◽  
Marko Sarstedt ◽  
Dipayan Biswas
Keyword(s):  
Large Scale ◽  
Field Experiments ◽  
Field Studies ◽  
Long Term Effects ◽  
Short Term ◽  
Railway Company ◽  
Short And Long Term ◽  
Ambient Scents ◽  
Short Term Effects

Ambient scents are being increasingly used in different service environments. While there is emerging research on the effects of scents, almost nothing is known about the long-term effects of consumers’ repeated exposure to ambient scents in a service environment as prior studies on ambient scents have been lab or field studies examining short-term effects of scent exposure only. Addressing this limitation, we examine the short- and long-term effects of ambient scents. Specifically, we present a conceptual framework for the short- and long-term effects of nonconsciously processed ambient scent in olfactory-rich servicescapes. We empirically test this framework with the help of two large-scale field experiments, conducted in collaboration with a major German railway company, in which consumers were exposed to a pleasant, nonconsciously processed scent. The first experiment demonstrates ambient scent’s positive short-term effects on consumers’ service perceptions. The second experiment—a longitudinal study conducted over a 4-month period—examines scent’s long-term effects on consumers’ reactions and demonstrates that the effects persist even when the scent has been removed from the servicescape.

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