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How to Improve Standard Farm Crops in Cochise CountyPaschall, A. L. 10 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
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End-border effects in fall-sown irrigated barley yield trialsBhalli, Masood Ahmad, 1937- January 1963 (has links)
No description available.
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A comparison of liquid and solid forms of nitrogen fertilizers for the decomposition of crop residuesFenn, Lloyd B. January 1963 (has links)
No description available.
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Effect of hill spacing and number of plants per hill on yield and yield components of four barley cultivarsWelty, Leon E. January 1973 (has links)
No description available.
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GROWTH, YIELD AND QUALITY RESPONSE OF BEET (BETA VULGARIS L.) TO NITROGENRantao, Gabriel 10 April 2014 (has links)
To study the quality response of beetroot to nitrogen fertilizers, a pot trial was conducted in
the glasshouse facility of the Department of Soil, Crop and Climate Sciences, Faculty of
Natural and Agricultural Sciences, University of the Free State, during the 2011 season. The
effect of five nitrogen sources (limestone ammonium nitrate, ammonium nitrate, urea,
ammonium sulphate and urea ammonium nitrate) at five nitrogen levels (0, 50, 100, 150 and
200 kg N ha-1) on beetroot (Detroit Dark Red) on a Bainsvlei soil type was investigated. The
data collected was analyzed using Tukeyâs Least Significant Difference test, at 5% level of
significance to determine statistically significant differences between means.
The results showed that all fertilizers used resulted in a reduction in plant height for the first
six weeks of growth. Nitrogen application only increased plant height significantly from week
8 where the height of plants that received nitrogen, irrespective of the fertilizer used, were
significantly taller than control plants. At week 8 no significant differences in height were
noted between various nitrogen application rates, but by week 10 significant differences in
plant height were noted between the 50 kg N ha-1 and 150 kg N ha-1 or 200 kg N ha-1
application rates. The findings showed that beet plants reacted better to N-fertilization using
ammonium sulphate nitrate and urea ammonium nitrate than other nitrogen sources,
although limestone ammonium nitrate and ammonium nitrate also produced improvements
in plant growth, whereas plants that received urea showed no improvements.
Nitrogen at 100 kg ha-1 resulted in more leaves per plant than its application at other levels.
Urea ammonium nitrate as a nitrogen source significantly improved plant leaf area, leaf fresh
mass, total fresh mass and root diameter. Application of nitrogen at 200 kg ha-1 also
increased leaf area, leaf fresh mass, total fresh mass, beet diameter and beet volume. Urea
ammonium nitrate increased leaf dry mass by an average of 397% while the lowest leaf dry
mass by (139.42% of control) was observed with the use of limestone ammonium nitrate as
a nitrogen source. The greatest leaf dry mass was obtained at the highest rate of nitrogen
application (200 kg ha-1) and the lowest leaf dry mass was observed at the control level.
Beet yields were found to increase as the nitrogen application rate increased, from 2.99 t ha-
1 in the control treatments to 14.37 t ha-1 in the treatments that received 200 kg N ha-1.
Fertilizing with urea ammonium nitrate gave the highest yields (12.17 t ha-1), while using
limestone ammonium nitrate gave the lowest yields (9.00 t ha-1). Application of nitrogen at 50 kg ha-1 resulted in firmer beets than nitrogen application at other
levels. Beets from plants that did not receive any nitrogen were significantly softer than those
that received nitrogen at higher levels. The darkening of beet colour (decrease of L*) was
experienced at the control level while the highest changes of colour (increase of L*) was
obtained at the highest nitrogen level. Nitrogen at 100 kg ha-1 influenced the lowest change
of coefficient a from red to green while the control level resulted in more intensive change.
The results showed that nitrogen at the control level led to more intensive changes of
coefficient b colours from yellow to blue and its application at the highest level resulted in
less intensive changes of coefficient b colours from yellow to blue.
Neither nitrogen source nor nitrogen level had any effect on the pH, sucrose or fructose
contents of the roots. Application of nitrogen at 150 kg ha-1 resulted in greater total soluble
solids content in the roots, while the starch content of plants that received no nitrogen was
significantly greater than that of plants receiving nitrogen. Nitrogen application at 100 kg ha-1
and at the control level influenced the glucose content, which was significantly higher in
these plants than in those that received 50, 150 and 200 kg N ha-1, however, the highest
glucose content of the roots was observed at the control level.
Nitrogen application at 200 kg ha-1 resulted in higher nitrogen content in the leaves as
compared to application of other nitrogen sources at different levels. Limestone ammonium
nitrate influenced potassium content of the leaves more than other nitrogen sources.
Nitrogen application at 200 kg ha-1 resulted in a greater calcium content in the leaves than
other nitrogen sources. The highest sodium content of the leaves was observed at 150 kg N
ha-1 while the lowest sodium content was observed at 50 kg N ha-1. Urea ammonium nitrate
had a greater positive influence on the manganese content of the leaves than other nitrogen
sources. Plants that received no nitrogen had significantly greater levels of iron in the leaves
than at all nitrogen levels. Ammonium nitrate as a nitrogen source influenced the calcium
content of the beets more than other nitrogen sources. Other root minerals such as
phosphorus, potassium, sodium, magnesium, manganese, copper, iron and zinc were not
significantly influenced by nitrogen source or nitrogen level, or the interaction between these
factors.
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SOIL HYDROLOGY AND HYDRIC SOIL INDICATORS OF THE BOKONG WETLANDS IN LESOTHOMapeshoane, Botle Esther 10 April 2014 (has links)
Wetland hydrology controls the function of the wetland ecosystem and hence it is the
principal parameter for delineation and management of wetlands. It is defined as the water
table depth, duration, and frequency required for an area to develop anaerobic conditions in
the upper part of the soil profile leading to the formation of iron and manganese based soil
features called redoximorphic features. The redoximorphic features must occur at specific
depths in the soil profile with specific thickness and abundance to qualify for a hydric soil
indicators. Therefore, hydric soil indicators are used to evaluate the wetland hydrology if
such a relationship has been verified. The aims of the study were i) to determine soil
variation and hydric soils indicators along a toposequence, ii) to determine the relationships
between soil water saturation, redox potential and hydric soil morphological properties and
iii) to determine the distribution of soil properties and accumulation of soil organic carbon in
hydric and non-hydric soils.
The study was conducted at the upper head-water catchment of the Bokong wetlands in the
Maloti/Drakensberg Mountains, Lesotho. The soil temperature ranged between -10 and
23°C. The soils had a melanic A overlying an unspecified material with or without signs of
wetness, or a G horizon. The organic O occurred in small area. Soil profiles were dug along
a toposequence and described to the depth of 1000 mm or shallower if bedrock was
encountered. Redoximorphic features were described using standard soil survey
abundance categories. Soil samples were collected from each horizon and analysed for
selected physical and chemical soil properties.
The soils had low bulk density ranging from 0.26 in the topsoil to 1.1 Mg m-3 in the subsoil.
Significantly low bulk density was observed in the valleys and highest bulk densities were
observed on the summits. The soil organic carbon content ranged between 0.18% in the
subsoil and 14.9% in the topsoil. The soil also had a high dithionite extractable Fe (mean
93±53 g kg-1) and low CEC (mean 26±9 cmolc kg-1). Soil pH and CEC were relatively lower
in the valleys and higher on the summits. Principal component analysis indicated four
principal components accounted for 60% of the total variance. The first principal component
that contributed 23% of the variation showed high coefficients for soil properties related to
organic matter turnover, the second components were related to inherent fertility, the third
and fourth were related to acidity and textural variation.
Hydric indicators identified in Bokong were histisols (A1), histic epipedon (A2), thick dark
surfaces (A12), redox dark surfaces (F6), depleted dark surfaces (F7), redox depressions (F8), loamy gleyed matrix (F2) and umbric surfaces (F13). The thick dark surfaces with
many prominent depletions and gley matrix (A12 and F7) occurred in the valleys, while the
midslopes and footslopes were dominated by umbric surfaces (A13). The indicators F6, F7
and F8 were not common. Indicators that were related to the peat formation (A1, A2 and
F13) were frequently observed.
The relationship between soil water saturation and redoximorphic features was verified by
monitoring the groundwater table with piezometers, installed in ten representative wetlands
at depths of 50, 250, 500, 750, and 1000 mm for two years from September 2009 to August
2011. Redoximorphic feature abundance categories were converted into indices. Strong
correlations were observed between redoximorphic indices and cumulative saturation
percentage. The depth to chroma 3 and 4 (d_34) and depth to the gley matrix (d_gley)
correlations were R2 = 0.77 and R2 = 74 respectively. All redoximorphic indices were poorly
correlated with average seasonal high water table. Strong correlation were also observed
between profile darkening index (PDI) and cumulative saturation (R² = 0.88) and weak
correlations were observed between PDI and average seasonal high water table (R² = 0.63).
A paired t test indicated that soil pH, exchangeable Mg and Na, dithionite extractable Fe and
Al were significantly different between hydric and non-hydric soils. Hydric soils had
significantly higher Mg, Na and Fe content, and significantly low soil pH and Al content.
Generally it appeared that soluble phosphorus, Fe and exchangeable bases accumulated in
hydric soils, while the soil pH and Al content decreased. The mean soil organic carbon
contents were 3.61% in hydric soils and 3.38% in non-hydric soils. However, non-hydric soil
relatively stored more organic carbon (174.4 Mg C ha-1) than hydric soils (155.1 Mg C ha-1).
The mean soil organic carbon density of the study area was 166±78.3 Mg C ha-1) and the
estimated carbon stored was 21619 Mg C (0.022 Tg C; 1Tg = 1012g) within the 1000 mm soil
depth. About 384.9 Mg C was stored in the hydric soils within the study area, which was
about 1.9% of the total carbon stored in the area to the bedrok or depth of 1000 mm. Among
the wetland types, bogs had significantly higher organic carbon levels (6.17%) and stored
significantly higher carbon (179 Mg C ha-1) with at least 44% was store in the A1 horizon.
It was concluded that the strong correlation observed between PDI, d_34, d_gley and
cumulative saturation representing hydric indicators such as histisols (A1), histic epipedon
(A2), umbric surfaces (F13), loamy gleyed matrix (F2) can be used to determine the duration
and frequency of the water table in the landscape studied. These hydric indicators can be
used to delineate wetlands, however, more indicators can be developed.
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Yield-limiting processes in cowpea (Vigna unguiculata (L.) Walp.) cultivar Vita-5Argall, John F. January 1983 (has links)
No description available.
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The effect of inter- and intra-row spacings on the leaf area index, light interception and various agronomic characters of Zea Mays L.Msambo, Romano Bundala. January 1966 (has links)
Many factors are known to influence crop yields. Thus two of the basic plant growth requirements in the environment, namely, light and heat need be available to crop plants in specified quantities and/or qualities for good crop yields. In normal farm practice these two environmental factors are managed by proper cultural practices of the crops concerned. [...]
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Yield response of spring barley, Hordeum vulgare L., to plant density and nitrogen fertilization.Rentería-Delmar, Guillermo. January 1981 (has links)
No description available.
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A genetic analysis of harvest index in barley (Hordeum vulgare L. emend. Lam.) /El-Zayadi, Fawzi January 1985 (has links)
No description available.
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