Limitations to Productivity of Some Ultisol and Oxisol Subsoils

Greenhouse experiments with maize were carried out to see if the reported infertility of some subsoils could be improved with mineral fertilization and efficient watering. It was shown that the Nipe soil series (Typic Acrorthox; clayey, oxidic, isohyperthermic) exposed subsoil was as productive as the Carreras series (Aquic Tropohumult; clayey, kaolinitic, isohyperthermic) surface soil when N, K, micronutrients and 600 ppm P were added and the pots were watered by means of wicks. Carreras subsoil, when limed and fertilized with N, K, 300 ppm P, 100 ppm Mg and 36 ppm Zn produced as well as Carreras surface soil, even though it contained only about one-third as much organic matter. A comparison among eight surface and subsoils showed that yields on limed, liberally fertilized, well-watered Los Guineos series (Epiaquic Humoxic Tropohumult; clayey, kaolinitic, isothermic) surface soil, Carreras surface soil, Piña series (Psammentic Haplorthox; sandy, isohyperthermic) surface soil, Los Guineos subsoil, Piña subsoil and Catalina series (Tropeptic Haplorthox; clayey, oxidic, isohyperthermic) surface soil were not significantly different. However, the yield on the least productive of two Catalina subsoils was only 64 percent of the yield on the Los Guineos surface soil. But with the addition of Zn and slightly over 1,000 ppm P, greenhouse pot yields on the two soils were essentially the same. Field experiments will be necessary to determine optimum P rates under field conditions. It was concluded that the productivity in greenhouse pots of surface and subsoils of the Ultisols and Oxisols studied can all be brought to the same high level, provided adequate mineral fertilization (including Zn and high P rates), lime and water management are used.

Download Full-text

Soil stripping and replacement for the rehabilitation of bauxite-mined land at Weipa. I. Initial changes to soil organic matter and related parameters

Soil Research ◽

10.1071/sr99043 ◽

2000 ◽

Vol 38 (2) ◽

pp. 345 ◽

Cited By ~ 18

Author(s):

G. D. Schwenke ◽

D. R. Mulligan ◽

L. C. Bell

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Field Experiments ◽

Surface Soil ◽

Soil Disturbance ◽

Microbial Biomass C ◽

Low Grade ◽

Double Pass ◽

Organic C ◽

The Difference

At Weipa, in Queensland, Australia, sown tree and shrub species sometimes fail to establish on bauxite-mined land, possibly because surface-soil organic matter declines during soil stripping and replacement. We devised 2 field experiments to investigate the links between soil rehabilitation operations, organic matter decline, and revegetation failure. Experiment 1 compared two routinely practiced operations, dual-strip (DS) and stockpile soil, with double-pass (DP), an alternative method, and subsoil only, an occasional result of the DS operation. Other treatments included variations in stripping-time, ripping-time, fertiliser rate, and cultivation. Dilution of topsoil with subsoil, low-grade bauxite, and ironstone accounted for the 46% decline of surface-soil (0–10 cm) organic C in DS compared with pre-strip soil. In contrast, organic C in the surface-soil (0–10 cm) of DP plots (25.0 t/ha) closely resembled the pre-strip area (28.6 t/ha). However, profile (0–60 cm) organic C did not differ between DS (91.5 t/ha), DP (107 t/ha), and pre-strip soil (89.9 t/ha). Eighteen months after plots were sown with native vegetation, surface-soil (0–10 cm) organic C had declined by an average of 9% across all plots. In Experiment 2, we measured the potential for post-rehabilitation decline of organic matter in hand-stripped and replaced soil columns that simulated the DS operation. Soils were incubated in situ without organic inputs. After 1 year’s incubation, organic C had declined by up to 26% and microbial biomass C by up to 61%. The difference in organic C decline between vegetated replaced soils (Expt 1) and bare replaced soils (Expt 2) showed that organic inputs affect levels of organic matter more than soil disturbance. Where topsoil was replaced at the top of the profile (DP) and not ploughed, inputs from volunteer native grasses balanced oxidation losses and organic C levels did not decline.

Download Full-text

Resistance of standing milkvetch (Astragalus adsurgens) varieties to Embellisia astragali

Crop and Pasture Science ◽

10.1071/cp12107 ◽

2012 ◽

Vol 63 (4) ◽

pp. 351 ◽

Cited By ~ 2

Author(s):

B. H. Yu ◽

Z. B. Nan ◽

Y. Z. Li ◽

H. L. Lin

Keyword(s):

Disease Severity ◽

Field Experiments ◽

Agronomic Traits ◽

Disease Incidence ◽

Dry Weight ◽

Severity Index ◽

Field Conditions ◽

Disease Severity Index ◽

Greenhouse Experiments ◽

Astragalus Adsurgens

Yellow stunt and root rot caused by Embellisia astragali are major factors contributing to declining yields of standing milkvetch (Astragalus adsurgens). The resistance of ten varieties of standing milkvetch to E. astragali was evaluated under laboratory, greenhouse, and field conditions. Seed germination/emergence, shoot and root length, plant dry weight, disease incidence, mortality, and disease severity index were monitored. The results show that Shanxi and Zhongsha No. 1 varieties had the best agronomic traits and lowest levels of disease in all experiments, while the varieties Neimeng and Ningxia had the highest susceptibility to disease. Germination/emergence differed significantly (P < 0.05) between varieties after inoculation, and compared with the control, germination/emergence of inoculated treatments of nine varieties decreased on average by 1.5% in laboratory experiments and by 4.1% in greenhouse experiments at 15 days after inoculation. Inoculation reduced shoot length by an average of 24.4% and 41.5% (P < 0.05) in laboratory and greenhouse experiments, respectively, in six of ten varieties. All varieties showed significantly (P < 0.05) lower plant dry weight following inoculation, with reductions ranging from 0.3 to 0.6 mg in the laboratory and from 82.6 to 149.4 mg in the greenhouse. Resistance to the pathogen was evaluated on the basis of disease incidence, a disease severity index (DSI), and mortality; varieties showing different resistance were grouped using cluster analysis. There were significant correlations between the results of laboratory and greenhouse experiments (r = 0.79; P < 0.01) and between greenhouse and field experiments (r = 0.83; P < 0.01) across all varieties. Multiple regression analysis between laboratory/greenhouse and field experiments on DSI suggested that screening in the laboratory/greenhouse could be an alternative method of rapidly estimating DSI under field conditions.

Download Full-text

Norflurazon adsorption and dissipation in three southern soils

Weed Science ◽

10.1017/s0043174500092870 ◽

1997 ◽

Vol 45 (2) ◽

pp. 301-306 ◽

Cited By ~ 7

Author(s):

William T. Willian ◽

Thomas C. Mueller ◽

Robert M. Hayes ◽

David C. Bridges ◽

Charles E. Snipes

Keyword(s):

Organic Matter ◽

Soil Profile ◽

Surface Soil ◽

Field Conditions ◽

Loamy Sand ◽

Soil Horizon ◽

Silt Loam ◽

Laboratory Conditions ◽

Soil Zone ◽

Field And Laboratory Conditions

Norflurazon adsorption and dissipation under field and laboratory conditions, and distribution within the soil profile were determined in three soils representative of cotton-growing regions of the southeastern U.S. Norflurazon adsorption was greater in soil from 0 to 8 cm in a Lexington silt loam (Tennessee) and a Beulah silt loam (Mississippi) than in a Dothan loamy sand (Georgia). Adsorption was directly related to organic matter. Norflurazon degradation under controlled conditions in soil from 0 to 8 cm from each state was not different among locations, with half-lives ranging from 63 to 167 d. Degradation at 30 C in soil from the 30- to 45- and 60- to 90-cm depths was not different among locations, and was slower at the 60- to 90-cm depth than in surface soil. Norflurazon dissipation was more rapid under field conditions than under laboratory conditions, with half-lives ranging from 7 to 79 d in the 0- to 8-cm soil horizon. Dry field conditions slowed norflurazon dissipation. Norflurazon was not detected below 15 cm in the profile in any soil, and concentrations in the 8- to 15-cm soil zone were < 36 ppbw 112 d after treatment.

Download Full-text

Alternatives for Control of Paraquat Tolerant American Black Nightshade (Solanum americana)

Weed Technology ◽

10.1017/s0890037x00033261 ◽

1991 ◽

Vol 5 (1) ◽

pp. 61-65 ◽

Cited By ~ 6

Author(s):

Thomas A. Bewick ◽

William M. Stall ◽

Stephen R. Kostewicz ◽

Kenneth Smith

Keyword(s):

Field Experiments ◽

Dry Weight ◽

Field Conditions ◽

Metal Chelator ◽

Greenhouse Experiments ◽

Black Nightshade ◽

Herbicide Treatments ◽

American Black

Greenhouse and field experiments were conducted to identify alternative herbicide treatments for the control of a biotype of American black nightshade which has been shown to tolerate paraquat. In greenhouse experiments the combination of paraquat and the metal chelator diethyldithiocarbamate at either 1% w/v or 3% w/v, and diquat alone significantly lowered I50values, based on dry weight, when compared with paraquat alone. None of these treatments provided acceptable control (>90%) in field experiments. Treatments that controlled American black nightshade under field conditions were: monocarbamide dihydrogensulfate at 9 kg ai ha-1, monocarbamide dihydrogensulfate at 9 kg ha-1+ paraquat at 0.6 kg ha-1, lactofen at 0.6 kg ha-1, oxyfluorfen at 0.6 kg ha-1, and acifluorfen at 0.6 kg ha-1. Addition of tridiphane at 1.7 kg ha-1to paraquat at 0.6 kg ha-1did not improve control of American black nightshade under field conditions.

Download Full-text

Biological Control of Hemp Sesbania (Sesbania exaltata) Under Field Conditions withColletotrichum truncatumFormulated in an Invert Emulsion

Weed Science ◽

10.1017/s0043174500052243 ◽

1993 ◽

Vol 41 (3) ◽

pp. 497-500 ◽

Cited By ~ 45

Author(s):

C. Douglas Boyette ◽

Paul C. Quimby ◽

Charles T. Bryson ◽

Grant H. Egley ◽

Floyd E. Fulgham

Keyword(s):

Biological Control ◽

Weed Control ◽

Field Experiments ◽

Field Conditions ◽

Colletotrichum Truncatum ◽

Greenhouse Experiments ◽

Sesbania Exaltata ◽

Invert Emulsion ◽

Emulsion Formulation ◽

Hemp Sesbania

In greenhouse experiments, conidia ofColletotrichum truncatumapplied in an invert emulsion formulation controlled hemp sesbania 100% in the absence of a dew treatment. In field experiments, hemp sesbania control averaged 95 and 97% in 1989 and 1990, respectively, when this formulation was applied to hemp sesbania seedlings using tractor-mounted, air-assist nozzles. This level of weed control was comparable to that achieved from the herbicide acifluorfen. These results indicate thatC. truncatumhas excellent potential as a mycoherbicide for controlling hemp sesbania and that this potential can be augmented by formulating the pathogen as an invert emulsion.

Download Full-text

EFFECTS OF SOIL ACIDITY ON RHIZOBIA NUMBERS, NODULATION AND NITROGEN FIXATION BY ALFALFA AND RED CLOVER

Canadian Journal of Soil Science ◽

10.4141/cjss77-024 ◽

1977 ◽

Vol 57 (2) ◽

pp. 197-203 ◽

Cited By ~ 56

Author(s):

W. A. RICE ◽

D. C. PENNEY ◽

M. NYBORG

Keyword(s):

Nitrogen Fixation ◽

Soil Ph ◽

Soil Acidity ◽

Field Experiments ◽

Rhizobium Meliloti ◽

Acid Soils ◽

Red Clover ◽

Ion Concentration ◽

Hydrogen Ion Concentration ◽

Greenhouse Experiments

The effects of soil acidity on nitrogen fixation by alfalfa (Medicago sativa L.) and red clover (Trifolium pratense L.) were investigated in field experiments at 28 locations, and in greenhouse experiments using soils from these locations. The pH of the soils (limed and unlimed) varied from 4.5 to 7.2. Rhizobia populations in the soil, nodulation, and relative forage yields (yield without N/yield with N) were measured in both the field and greenhouse experiments. Rhizobium meliloti numbers, nodulation scores, and relative yields of alfalfa decreased sharply as the pH of the soils decreased below 6.0. For soils with pH 6.0 or greater, there was very little effect of pH on any of the above factors for alfalfa. Soil pH in the range studied had no effect on nodulation scores and relative yields of red clover. However, R. trifolii numbers were reduced when the pH of the soil was less than 4.9. These results demonstrate that hydrogen ion concentration is an important factor limiting alfalfa growth on acid soils of Alberta and northeastern British Columbia, but it is less important for red clover. This supports the continued use of measurements of soil pH, as well as plant-available Al and Mn for predicting crop response to lime.

Download Full-text

COR/LEA Proteins as Indicators of Frost Tolerance in Triticeae: A Comparison of Controlled versus Field Conditions

Plants ◽

10.3390/plants10040789 ◽

2021 ◽

Vol 10 (4) ◽

pp. 789

Author(s):

Klára Kosová ◽

Miroslav Klíma ◽

Ilja Tom Prášil ◽

Pavel Vítámvás

Keyword(s):

Cold Acclimation ◽

Field Experiments ◽

Quantitative Relationship ◽

Field Trials ◽

Frost Tolerance ◽

Late Embryogenesis Abundant ◽

Field Conditions ◽

Lea Proteins ◽

Winter Cereals ◽

Vernalisation Requirement

Low temperatures in the autumn induce enhanced expression/relative accumulation of several cold-inducible transcripts/proteins with protective functions from Late-embryogenesis-abundant (LEA) superfamily including dehydrins. Several studies dealing with plants grown under controlled conditions revealed a correlation (significant quantitative relationship) between dehydrin transcript/protein relative accumulation and plant frost tolerance. However, to apply these results in breeding, field experiments are necessary. The aim of the review is to provide a summary of the studies dealing with the relationships between plant acquired frost tolerance and COR/LEA transcripts/proteins relative accumulation in cereals grown in controlled and field conditions. The impacts of cold acclimation and vernalisation processes on the ability of winter-type Triticeae to accumulate COR/LEA proteins are discussed. The factors determining dehydrin relative accumulation under controlled cold acclimation treatments versus field trials during winter seasons are discussed. In conclusion, it can be stated that dehydrins could be used as suitable indicators of winter survival in field-grown winter cereals but only in plant prior to the fulfilment of vernalisation requirement.

Download Full-text

FACTORS AFFECTING ADULT EMERGENCE AND MATING BEHAVIOR OF THE EASTERN SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

The Canadian Entomologist ◽

10.4039/ent107967-9 ◽

1975 ◽

Vol 107 (9) ◽

pp. 967-977 ◽

Cited By ~ 27

Author(s):

C. J. Sanders

Keyword(s):

Field Experiments ◽

Choristoneura Fumiferana ◽

Adult Emergence ◽

Spruce Budworm ◽

Field Conditions ◽

Continuous Illumination ◽

Degree Days ◽

Factors Affecting ◽

Eastern Spruce Budworm ◽

Duration Of Copulation

AbstractLaboratory and field experiments indicate that the female spruce budworm (Choristoneura fumiferana (Clem.)) pupal stadium requires approximately 122C degree-days above a threshold of 7.2 °C (45°F), the male 124. Emergence time on any given day depends on temperature but is independent of photoperiod. Under field conditions male and female budworm mate only once per 24-h period. In the laboratory under continuous illumination females mate repeatedly and males readily mate a second time within a few hours, but the duration of the second copulation is abnormally long. The probability of multiple matings under field conditions is reduced by the restricted period of sexual activity coupled with the duration of copulation and the lower competitiveness of mated insects. Antennae are essential to the male for successful copulation.

Download Full-text

Interaction of Bentazon and Imazethapyr Applied Postemergence to Nutsedge (Cyperus spp.)

Peanut Science ◽

10.3146/i0095-3679-22-2-14 ◽

1995 ◽

Vol 22 (2) ◽

pp. 150-154

Author(s):

Alan C. York ◽

John W. Wilcut

Keyword(s):

Ammonium Salt ◽

Sodium Salt ◽

Field Experiments ◽

Pyridinecarboxylic Acid ◽

Purple Nutsedge ◽

Yellow Nutsedge ◽

Greenhouse Experiments

Abstract Field and greenhouse experiments evaluated purple nutsedge (Cyperus rotundas L.) and yellow nutsedge (C. esculentus L.) control with mixtures of bentazon [3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide] and imazethapyr {2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-ethyl-3-pyridinecarboxylic acid} applied postemergence. Mixtures of the sodium salt of bentazon at 0.6 or 1.1 kg ae/ha and the ammonium salt of imazethapyr at 35 or 70 g ae/ha were antagonistic on purple nutsedge in field and greenhouse experiments. Mixtures of bentazon at 0.6 kg/ha and imazethapyr at 35 or 70 g/ha were additive on yellow nutsedge in field experiments but antagonistic in greenhouse experiments. Mixtures of bentazon at 1.1 kg/ha and imazethapyr at 35 or 70 g/ha were antagonistic on yellow nutsedge in field and greenhouse experiments.

Download Full-text