Changes of Soil Microbial Biomass C and P During Wheat Growth After Application of Fertilizers

A pot experiment was carried out with a clay loam in a green house. The results showed that soil microbial biomass C increased with the application of organic manure at the beginning of the experiment and then gradually decreased with declining of the temperature. The soil biomass C increased at the tillering stage when the temperature gradually increased, and rose to the highest value at the anthesis stage, being about 554.9-794.4 mg C kg-1. The application of organic manure resulted in the highest increase in biomass C among the fertilization treatments while that of ammonium sulphate gave the lowest. At the harvest time the soil biomass C decreased to the presowing level. Like the soil biomass C the amount of biomass P was increased by the incorporation of organic manure and was the highest among the treatments, with the values of the check and ammonium sulphate treatments being the lowest. Meanwhile, the changing patterns of the C/P ratio of soil microbial biomass at stages of wheat growth are also described.

A Novel Method for Determining Microbial Kinetics

Understanding microbial growth is essential to any research conducted in the fields of microbiology and biotechnology. Current methods of determining growth characteristics of microbes involve subjective graphical interpretations of linearized logarithmic data. Reducing error in logistical data decreases disparity between graphical and analytical predictions of microbial characteristics. In this study, a method has been developed to calculate the kinetics of microbial characteristics utilizing a modified Maclaurin series. Convergence of this series approaches the true kinetic value of microbial characteristics to include specific growth rates. In this research, a modified Maclaurin series is used to evaluate microbial kinetics in comparison to graphical determinations.

Comparative Analysis of Energy Efficiency in Wheat Production in Different Climate Conditions of Europe

This paper presents results concerning energy efficiency of wheat production considered in the context of specific energy input variation in different climatic conditions of Europe as well as case studies on implementation of selected energy saving measures in practice. The source data collected from the six european union （EU） countries represent five agricultural regions of continental Europe and three climates： continental, temperate and Mediterranean. The life cycle assessment （LCA） methodology was applied to analyze the data excluding of pre-farm gate activities. The total primary energy consumption was decomposed into main energy input streams and it was regressed to yield. In order to compare energy efficiency of wheat production across the geographical areas, the data envelopment analysis （DEA） was applied. It was shown that the highest wheat yield （6.7 t/ha to 8.7 t/ha） at the lowest specific energy input （2.08 GJ/t to 2.56 G J/t） is unique for temperate climate conditions. The yield in continental and Mediterranean climatic conditions is on average lower by 1.3 t/ha and 2.7 t/ha and energy efficiency lower by 14% and 38%, respectively. The case studies have shown that the energy saving activities in wheat production may be universal for the climatic zones or specific for a given geographical location. It was stated that trade-offs between energy, economic, and environmental effects, which are associated with implementation of a given energy saving measure or a set of measures to a great extent depend on the current energy efficiency status of the farm and opportunity for investment, which varies substantially across Europe.

The effect of 2, 4-Dichlorophenoxy acetic acid and Bradyrhizobium on induction of Para-nodule in wheat roots

The investigation was conducted to know the effect of 2, 4-Dichlorophenoxy acetic acid and inoculation on Para-nodule formation and growth parameters in wheat. Formation of nodular outgrowth on the roots of wheat seedlings treated with 2, 4-D commenced in 8-10 days. The maximum Para-nodule formation was found in 1 ppm of 2, 4-D when incubated with bradyrhizobium P-132. Inoculation of the same has helped to increase the number of Para-nodule, but not essential for Para-nodulation. Histological study shows that, these induced Para-nodules originated from the pericycle and these are appeared to be modified lateral roots and Para-nodule structure formations however, it enhanced by bradyrhizobial inoculation.

Identification of QTLs for yield and yield components of barley under different growth conditions

Waterlogging is a major abiotic stress limiting barley (Hordeum vulgare L.) yield and its stability in areas with excessive rainfall.Identification of genomic regions influencing the response of yield and its components to waterlogging stress will enhance our understanding of the genetics of waterlogging tolerance and the development of more tolerant barley cultivars.Quantitative trait loci (QTLs) for grain yield and its components were identified using 156 doubled haploid (DH) lines derived from a cross between the cultivars Yerong (waterlogging-tolerant) and Franklin (waterlogging-sensitive) grown under different conditions (waterlogged and well drained).A total of 31 QTLs were identified for the measured characters from two experiments with two growth environments.The phenotypic variation explained by individual QTLs ranged from 4.74% to 55.34%.Several major QTLs determining kernel weight (KW),grains per spike (GS),spikes per plant (SP),spike length (SL) and grain yield (GY) were detected on the same region of chromosome 2H,indicating close linkage or pleiotropy of the gene(s) controlling these traits.Some different QTLs were identified under waterlogging conditions,and thus different markers may have to be used in selecting cultivars suitable for high rainfall areas.