One of the major limitations to obtain satisfactory soybean (Glycine max (L.) Merr.) yield in acid soils in many developing countries is the purchasability of liming materials. For many low income farmers, liming to the 'ideal' soil pH of 6.5 using conventional methods is usually too expensive. Pot and field studies were conducted to determine whether satisfactory soybean growth could be obtained by reducing the amount of lime applied and the volume of soil limed. The Quebec soils used in these studies were a Gray-brown Luvisol (pH 5.1) and a Humic Gleysol (pH 5.3) in the pot study and a Gray-brown Luvisol (pH 5.1) and a Dark-gray Gleysol (pH 6.1) in the field study. / Results suggest that localizing the lime in acid Quebec soils would be a more efficient use of the liming material. Further studies in tropical acid soils are required to determine if the localized placement of lime is a viable practice for third-world, low income farmers. (Abstract shortened by UMI.)

No description available.

The effect of salinity on phosphorus (P) absorption kinetics by 'Russet Burbank' cv. potato propagated by tissue culture technique was studied in the laboratory. Nine clones of the cultivar were evaluated for their salt tolerance at the vegetative stage by using in vitro culture. Four concentrations of NaCl (0, 40, 80, and 120 mM) were used in the experiments. The first experiment was carried out to study the effect of salinity on P absorption by using radiophosphorus ($ sp{32}$P) as a marker. P absorption showed a quadratic relationship with time. In general, there was a significant reduction in P absorption as the NaCl concentration increased in the nutrient medium. However, the root tip concentration of $ sp{32}$P increased with increased salt concentration. When P concentration in the nutrient medium was increased, $ sp{32}$P activity was also increased with time at 120 mM salt concentration. The activity of radiophosphorus decreased on root tips when P concentration in the nutrient medium was increased to 2.5 mM P. The second experiment was conducted in tissue culture using nodal cutting bioassay. The plant morphological parameters of shoot length, shoot fresh weight, shoot dry weight, root length, root fresh weight, and root dry weight were reduced for all nine clones as salinity increased. The clone PEI#1 (tu) exhibited high salt tolerance characteristics.

Biological soil inoculants are products that contain beneficial microorganisms with the ability to increase plant-available nutrients. Soil inoculants are claimed to serve as a supplement for fertilizer N, improve germination and tilth, improve root systems, and increase crop quality and yield. The inoculant evaluated in this study was Effective Microorganisms (EM) produced by Nature Farm Foundation of Lompoc, California. A field trial with corn (Zea mays, L.) was conducted at Oakwood Organic Farm in East Central Indiana in 1992. Two soil types were used in the study, a Genesee silt loam (Fluventic Eutorchrept) and a Sloan silt loam (Fluventic Haplaquoll). Soil nitrate level measured through the growing season was not significantly affected by the addition of EM. Neither foliar nutrient content nor grain dry matter yield were significantly greater with use of EM compared to the control. / Department of Natural Resources

This paper looks at the determinants of bond yields for a select group of Eurozone countries, during the European sovereign debt crisis. In addition to traditional determinants of spreads, which include credit risk, liquidity risk and international risk aversion, this paper looks at the role of credit rating agencies. The movements of countries’ yields during the debt crisis played an integral role in the resulting bailouts by the European Union. Using expected data published by the European Commission, the results of the model were in line with current literature, with the exception of the effect of budget deficits. One interpretation of the conflicting results is that during a debt crisis what market participants care about is growth, not austerity. Including the effect of credit ratings showed that credit ratings have high predictive power.

Fertilizer applications of urea and triple superphosphate (TSP) suffer from low efficiency for corn production. Band or broadcast application of urea with acidic-P fertilizers may increase fertilizer efficiency. Urea and acidic-P fertilizer interactions in soil-fertilizer microsites were investigated using two Quebec soils. Adding acidic phosphates such as TSP and monoammonium phosphate (MAP) to urea reduced pH in microsites, urea hydrolysis, NH$ sb3$ volatilization, and increased soil NH$ sb4$- and NO$ sb3$-N contents. Ammonia loss decreased as P$ rm sb2O sb5$: urea-N ratios increased. Adding urea to P fertilizer increased soil pH and P sorption when using CaCl$ sb2$ as the electrolyte. Urea application increased 0.5 M NaHCO$ sb3$ extractable P. Banding urea with TSP caused dissolution of organic matter in soils, and increased P diffusion and P concentration in soil solution sampled with filter paper or in 1 M KCl extraction. Two years of field experiments demonstrated that banding urea with TSP or MAP increased soil extractable P (Mehlich-3), N and P nutrient uptake, plant growth and development of corn. Greater P fertilizer efficiencies and higher yields were achieved by banding urea-acidic P fertilizers.

An experiment was conducted to investigate the effects of N formulation, application rate, and application time on corn yield and quality under Eastern Canadian conditions, to evaluate the hypothesis that application of N will increase corn grain yield and protein concentration without decreasing the total energy content. Three N formulations, each with the rates of 90, or 180 kg ha$ sp{-1}$ were applied at different times. The results indicated that the grain yield increased with increasing N fertilizer rate and with increasing numbers of N application times. N application significantly increased grain protein concentration, on both a per kernel and a dry matter basis, and protein yield. Such as, N application increased the averaged protein concentration, on a dry matter basis, of corn grain by about 8.40% as compared to the control. The protein concentration was not affected by the number of N application times before the plants were 90 cm high. Neither lipid nor non-structural carbohydrate concentration, on both a per kernel and a dry matter basis, were significantly affected by N application in most of the location-years. In addition Near infrared reflectance (NIR) was used to determine the lipid concentration in the aerial corn tissue at different growth stages. The correlation coefficients between the standard analytical method and the NIR method of lipid concentration were all above 0.95, and were significant at 0.01 level.

No description available.

A study was conducted for two growing seasons in northeastern Syria to evaluate the effect of N and P fertilizers and previous crops--i.e. vetch (Vicia sativa L.), barley (Hordeum vulgare L. cv. Beecher) or fallow--on water consumption, development, growth and yields of barley in a semi-arid, Mediterranean-type climate. / The two seasons contrasted in rainfall and temperature which affected soil N, water use and yields. Fertilizer addition and residual P were the major determinants in barley yield increases. Rotation effects were significant only when fertilizers were added. Fallowing was an inefficient way of storing water, but stored water was used most efficiently by subsequent barley crops when fertilized. / Fertilizers did not increase total evapotranspiration. Water use efficiency was related to dry matter production at stem elongation (DMse). Grain weight was a stable component of grain yields. Grain number was related to crop growth rates during the three week pre-anthesis period and to DMse, in turn affected by temperature, nutrient and moisture conditions. / Vetch yields were in the order of 2.5 t.ha$ sp{-1}$ in the wetter season (1982/83). / Results showed that substantial barley yield increases can be obtained with innovative crop rotations and appropriate use of fertilizers in semi-arid environments.

The objectives of the study were to determine whether intercropped alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.) or rye grass (Lolium multiflorum Lmk.) could simultaneously contribute to the nitrogen regime of grain-corn (ie: increased yield), improve edaphic quality, and decrease the level of inorganic nitrogen present in the soil after corn harvest. To achieve these objectives the seeding of the intercrops was delayed, the corn population was increased, and the red clover was spring-ploughed. / Fall-ploughed red clover maintained the mean weight diameter (MWD) of aggregates on the Ste-Rosalie clay. Spring-ploughed red clover on the other hand caused a decrease in bulk density in the top 10 cm of the Chicot loam. / The nitrogen-response of corn indicated that the intercrops did not contribute to the nitrogen regime of grain-corn. There were also indications that intercrops competed with corn for available inorganic nitrogen and water. The intercrops, however, did reduce the levels of soil inorganic nitrogen in the fall allowing for a possible decrease in the nitrogen load of soil percolates. / Despite the beneficial effect of nitrogen fertilisation on the organic nitrogen content of the soil, the presence of leguminous intercrops did not prevent the increase of the soil CN ratio.