RELATIONSHIPS AMONG SOIL MOISTURE STRESS, PLANT POPULATIONS, ROW SPACING AND YIELD OF CORN

1970 ◽  
Vol 50 (1) ◽  
pp. 31-38 ◽  
Author(s):  
J. M. FULTON
Keyword(s):  
Soil Moisture ◽  
Maximum Yield ◽  
Soil Surface ◽  
Moisture Stress ◽  
High Population ◽  
Yield Reduction ◽  
Plant Populations ◽  
High Soil Moisture ◽  
High Soil ◽  
Available Soil Moisture

Experiments including variables of soil moisture, plant populations and row spacings were conducted in four consecutive seasons. In two of the years precipitation was inadequate to produce maximum yield of corn.Yield was reduced by soil moisture tension in excess of five bars at a point 40 cm below the soil surface. Substantial yield reduction occurred even where the moisture stress was confined to the period subsequent to tassel emergence. Highest yields were obtained where high soil moisture levels (minimum available soil moisture 25% at 40 cm) were combined with high population (54,362 plants per hectare) and narrow (50 cm) rows. However, interactions among these variables were such that narrow rows increased yield only in the presence of both high population and high soil moisture supply. High plant populations increased yield only where soil moisture levels were high.

scholarly journals White Root Rot of Raspberries

1951 ◽  
Vol 4 (3) ◽  
pp. 211
Author(s):  
GC Wade
Keyword(s):  
Soil Moisture ◽  
Root Rot ◽  
Soil Moisture Content ◽  
Soil Conditions ◽  
Causal Organism ◽  
White Root Rot ◽  
High Soil Moisture ◽  
High Soil ◽  
Soil Temperatures ◽  
Dry Soil

The disease known as white root rot affects raspberries, and to a less extent loganberries, in Victoria. The causal organism is a white, sterile fungus that has not been identified. The disease is favoured by dry soil conditions and high soil temperatures. It spreads externally to the host by means of undifferentiated rhizomorphs; and requires a food base for the establishment of infection. The spread of rhizomorphs through the soil is hindered by high soil moisture content and consequent poor aeration of the soil.

Laboratory and field studies on the degradation of fipronil in a soil

Soil Research ◽  
2002 ◽  
Vol 40 (7) ◽  
pp. 1095 ◽  
Author(s):  
Guang-Guo Ying ◽  
Rai Kookana
Keyword(s):  
Soil Moisture ◽  
Half Life ◽  
Soil Moisture Content ◽  
Soil Surface ◽  
Field Studies ◽  
Transformation Product ◽  
Laboratory Studies ◽  
The Third ◽  
High Soil Moisture ◽  
Sulfone Derivatives

Degradation of a new insecticide/termiticide, fipronil, in a soil was studied in the laboratory and field. Three metabolites of fipronil (desulfinyl, sulfide, and sulfone derivatives) were identified from soils after treatment. Laboratory studies showed that soil moisture content had a great effect on the degradation rate of fipronil and products formed. High soil moisture contents (>50%) favored the formation of a sulfide derivative of fipronil by reduction, whereas low soil moisture (<50%) and well-aerated conditions favored the formation of fipronil sulfone by oxidation. Microorganisms in soil accelerated the degradation of fipronil to sulfide and sulfone derivatives. The third transformation product, a desulfinyl derivative, was formed by photodecomposition of fipronil in water and on the soil surface under sunlight. The desulfinyl derivative degraded rapidly in field soils with a half-life of 41–55 days compared with an average half-life of 132 days for fipronil. The half-life of the 'total toxic component' (fipronil and its metabolites) in field soil was 188 days on average.

EFFECTS OF SOIL MOISTURE TENSIONS ON GROWTH OF WHEAT

1962 ◽  
Vol 42 (1) ◽  
pp. 180-188 ◽  
Author(s):  
J. J. Lehane ◽  
W. J. Staple
Keyword(s):  
Soil Moisture ◽  
Early Stage ◽  
Moisture Stress ◽  
Field Conditions ◽  
Grain Production ◽  
Optimum Conditions ◽  
High Soil Moisture ◽  
Early Stress ◽  
Moisture Supply ◽  
Favorable Conditions

Greenhouse experiments in which wheat was grown on a limited amount of soil moisture showed that crops subjected to moisture stress at an early stage of growth yielded well on all soils tested, but that crops with moisture stress late in the season yielded poorly on loam soils. Late stress was less damaging on clay because high soil moisture tension in this soil resulted in better distribution of moisture use during the critical period.Crops grown under early stress used less moisture, but were equally as efficient in grain production as those grown under optimum conditions. Crops with moisture shortage during heading and filling were inefficient in moisture use.Similar variations in moisture efficiency caused by seasonal trends in available moisture supply have been observed under field conditions. For example, good yields of wheat were produced with a minimum of rainfall in Saskatchewan in 1958 when a shortage of moisture in May and June was followed by more favorable conditions in July.

Annual pattern of soil moisture stress under sown and native pastures

1959 ◽  
Vol 10 (4) ◽  
pp. 518 ◽  
Author(s):  
JE Begg
Keyword(s):  
Soil Moisture ◽  
New England ◽  
General Pattern ◽  
Moisture Stress ◽  
Soil Conditions ◽  
Soil Moisture Stress ◽  
South Wales ◽  
Native Pasture ◽  
Available Soil Moisture ◽  
Native Pastures

Soil moisture fluctuations were measured under a phalaris-white clover pasture and under three native pasture types in the New England region of New South Wales over a 4-year period, by means of the gypsum resistance block technique. The results indicate that large differences in available soil moisture occur at times within areas of apparently similar soil type and that these differences are reflected by the different pasture types in the area. Although the lengths of the period during which soil moisture was unavailable differed considerably under the different pastures the general pattern was similar. The months of greatest soil moisture stress were December, January, April, and May, while the period of most favourable soil moisture was from June to November. Thus although most of the rain fell during the period December to May the rain which fell from June to November was more effective in maintaining available soil moisture. The subsoil dried out more rapidly and remained dry for a longer period under the sown pasture than under the native pasture type which the area previously carried, owing to the greater rate of removal of available soil moisture from under the sown pasture. Of the three native pasture types studied, the most favourable soil moisture pattern for plant growth occurred under the Sorghum-Themeda pasture. This pasture type may be a useful indicator of areas with soil conditions favourable for the growth of productive sown pastures.

Environment and Chlorsulfuron Phytotoxicity

Weed Science ◽  
1985 ◽  
Vol 33 (3) ◽  
pp. 395-399 ◽  
Author(s):  
John D. Nalewaja ◽  
Zenon Woznica
Keyword(s):  
Soil Moisture ◽  
Soil Nitrogen ◽  
Setaria Viridis ◽  
Kochia Scoparia ◽  
Humidity Effects ◽  
High Soil Moisture ◽  
High Soil ◽  
Green Foxtail ◽  
Temperature And Humidity ◽  
Reduced Toxicity

Glasshouse and growth chamber experiments were conducted to determine chlorsulfuron {2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino] carbonyl] benzenesulfonamide} phytotoxicity to kochia [Kochia scoparia(L.) Schrad. ♯ KCHSC] and green foxtail [Setaria viridis(L.) Beauv. ♯ SETVI] as influenced by temperature and humidity for 1 week after treatment, and by soil moisture and nitrogen. Chlorsulfuron was more phytotoxic to both kochia and green foxtail at 95 to 100% than at 45 to 50% relative humidity for 1 week after treatment whether at 10, 20, or 30 C. Chlorsulfuron phytotoxicity was similar with all posttreatment temperatures at each humidity, except that phytotoxicity was lower at 30 C than at 10 or 20 C at 90 to 100% humidity. Surfactant added to chlorsulfuron exhanced control of kochia more than that of green foxtail and overcame temperature and humidity effects on chlorsulfuron phytotoxicity. A simulated rainfall of 2 mm after chlorsulfuron application reduced toxicity of chlorsulfuron to green foxtail more than to kochia. Chlorsulfuron was more phytotoxic to green foxtail growing with a high than a low soil nitrogen level. High soil moisture following chlorsulfuron application enhanced phytotoxicity to kochia and green foxtail compared to high soil moisture before treatment.

A GREENHOUSE EVALUATION OF THE EFFECTS OF SOIL MOISTURE, RELATIVE HUMIDITY, AND HELMINTHOSPORIUM SATIVUM INFECTION ON BRITTLENESS OF BARLEY AWNS

1964 ◽  
Vol 44 (2) ◽  
pp. 157-160
Author(s):  
R. B. MacLaren ◽  
J. D. E. Sterling
Keyword(s):  
Soil Moisture ◽  
Relative Humidity ◽  
Cell Structure ◽  
Ash Content ◽  
High Relative Humidity ◽  
High Soil Moisture ◽  
High Soil ◽  
Greenhouse Evaluation ◽  
Helminthosporium Sativum

High soil moisture and high relative humidity gave a higher incidence of brittle awns on barley than did restricted soil moisture and low relative humidity. Ash content of awns was highest when soil moisture and relative humidity were maintained at high levels. Helminthosporium sativum (P, K and B) infection reduced awn brittleness of one variety and had no effect on the others.No differences in cell structure of the awns were attributed to treatment.

MICROORGANISMS IN THE ROOT ZONE IN RELATION TO SOIL MOISTURE

1965 ◽  
Vol 11 (3) ◽  
pp. 483-489 ◽  
Author(s):  
E. A. Peterson ◽  
J. W. Rouatt ◽  
H. Katznelson
Keyword(s):  
Soil Moisture ◽  
Soil Moisture Content ◽  
Root Colonization ◽  
Microbial Population ◽  
Root Zone ◽  
Root Surface ◽  
High Soil Moisture ◽  
High Soil ◽  
High Level ◽  
Taxonomic Studies

The influence of soil moisture on the microbial population of rhizosphere soil and of the root surface (rhizoplane) of wheat was studied under controlled conditions. Fertile soil adjusted to 30%, 60%, and 90% of its moisture-holding capacity was used. Bacterial counts and numbers of specific "physiological groups" of bacteria all increased in the rhizosphere and the rhizoplane as soil moisture decreased. Taxonomic studies of the bacteria isolated from the rhizoplane showed a marked preponderance of species of Pseudomonas under conditions of low and intermediate soil moisture content. On the other hand species of Arthrobacter, Bacillus, and Cytophaga dominated the population at high soil moisture. Although the distribution of fungi on the roots was very similar for the low and intermediate moisture levels, there was some restriction of colonization at the high level. Species of Mortierella, Rhizopus, Chaetomium, Curvularia, and Helminthosporium were not represented among isolates from roots at high soil moisture and the relative incidence of species of Fusarium and Phoma decreased. However, high soil moisture favored root colonization by species of Rhizoctonia and sterile dark fungi.

Wheat residue management options for no-till corn

1997 ◽  
Vol 77 (2) ◽  
pp. 207-213 ◽  
Author(s):  
G. Opoku ◽  
T. J. Vyn
Keyword(s):  
Soil Moisture ◽  
Winter Wheat ◽  
Grain Yield ◽  
Soil Surface ◽  
Triticum Aestivum L ◽  
Residue Management ◽  
Yield Reduction ◽  
Management Options ◽  
Grain Yields ◽  
No Till

Corn (Zea mays L.) yield reduction following winter wheat (Triticum aestivum L.) in no-till systems prompted a study on the effects of tillage and residue management systems on corn growth and seedbed conditions. Four methods for managing wheat residue (all residue removed, straw baled after harvest, straw left on the soil surface, straw left on the soil surface plus application of 50 kg ha−1N in the fall) were evaluated at two tillage levels: fall moldboard plow (MP) and no-till (NT). No-till treatments required at least 2 more days to achieve 50% corn emergence and 50% silking, and had the lowest corn biomass at 5 and 7 wk after planting. Grain yield was similar among MP treatments and averaged 1.1 t ha−1 higher than NT treatments (P < 0.05). Completely removing all wheat residue from NT plots reduced the number of days required to achieve 50% corn emergence and increased grain yields by 0.43 and 0.61 t ha–1 over baling and not baling straw, respectively, but still resulted in 8% lower grain yields than MP treatments. Grain yield differences among MP treatments were insignificant regardless of the amount of wheat residue left on the surface or N application in the fall. Early in the growing season, the NT treatments where residue was not removed had lower soil growing degree days (soil GDD) compared with MP (baled) treatment, and higher soil moisture levels in the top 15 cm compared with all other treatments. The application of 50 kg N ha−1 in the fall to NT (not baled) plots influenced neither the amount of wheat residue on the soil surface, nor the soil NO3-N levels at planting. Our results suggest that corn response in NT systems after wheat mostly depends on residue level. Key words: Winter wheat, straw management, no-till, corn, soil temperature, soil moisture

Sign in / Sign up

Export Citation Format

Share Document