The effect of depopulation and restocking on reproductive and growth performances on Japanese commercial swine farms

This study compared the reproductive and growth performances of pigs before and after depopulation and restocking after a foot-and-mouth disease outbreak in Japan. Data for the time period before and after depopulation and restocking were obtained from three farrow-to-finish farms. As a result of depopulation and restocking, hygiene levels were improved, and common infectious diseases, such as porcine reproductive and respiratory syndrome and Aujeszky’s disease, remained undetected on the farms. Compared with before depopulation, reproductive and growth performances improved after depopulation; the number of total pigs born was higher, the postweaning mortality rate was lower, and the age at slaughter was lower (P<0.05). In summary, depopulation and restocking improved the reproductive and growth performances of pigs.     

Effect of nitrogen application at the flowering stage on the quality of soybean seeds

Application of nitrogen (N) fertilizer at the flowering stage changed the contents of storage compounds in seeds of Soybean (Glycine max L. cvs Enrei and Tamahomare). The effects of the N application on the maturation of soybean seeds were examined by comparing changes in the contents of amino acids, sugars, water, protein, and oil in seeds from N‐dressed plants (NDS) with those from undressed plants (UDS) during maturation. The application resulted in a decrease of contents of total and some amino acids (glutamine and asparagine) in developing seeds except for at the early maturation stage and in a decreased protein content of mature seeds. On the other hand, the N application led to faster accumulation of oil in developing seeds and to an increased oil content of mature seeds. Based on these results, it was concluded that the N application at the flowering stage changed the composition of solutes imported by developing seeds and resulted in variations in the contents of storage compounds. The results indicate that it is possible to improve seed quality by fine control of N application.     

Characterization of plasma membrane-bound Fe3+-chelate reductase from Fe-deficient and Fe-sufficient cucumber roots

Abstract

One of the authors analyzed the brown spot symptoms developed on plant leaves caused by nutritional disorders using an X-ray Micro-Analyser (Sasaki et al. 1980). The use of an X-ray Fluorescence Element Mapping Spectrometer (XEMS) revealed that external and internal stresses such as X-ray irradiation and manganese excess induced the transport of manganese, and excess of manganese concentration as cationic Mn²⁺ was related to the formation of the abnormal brown spots (Watanabe and Kobayashi 1986; Watanabe et al. 1988). Since, the mechanism of the transport of manganese remains to be elucidated the analysis of the chemical state of manganese in plant is important. Since the valency of manganese readily changes depending on the redox potential, non-destructiye analysis may be effective. In fact, few studies have been carried out on the non-destructive determination of the manganese state in plant tissues. We studied the state of manganese in rice leaf in performing Extended X-ray Absorption Fine Structure (EXAFS) and X-ray Absorption Near Edge Structure (XANES) analyses by X-ray Absorption Spectrometry with syncrotron radiation as the analytical source. X-ray absorption spectrometry provides structural information about the local surroundings of a metal ion, the binding configuration, etc. The concept and method of analysis were reviewed in detail by Teo (1981). The advantage of these methods over the previous methods is reported and the state and transport of manganese in leaf are discussed.     

Quantitative analysis of the initial transport of fixed nitrogen in nodulated soybean plants using 15N as a tracer

The quantitative analysis of the initial transport of fixed isotope 15-nitrogen (¹⁵N) in intact nodulated soybean plants (Glycine max [L.] Merr. cv. Williams) was investigated at the vegetative stage (36 days after planting, DAP) and pod-filling stage (91 DAP) by the ¹⁵N pulse-chase experiment. The nodulated roots were exposed to N₂ gas labeled with a stable isotope ¹⁵N for 1 h, followed by 0, 1, 3 and 7 h of exposure with normal air. Plant roots and shoots were separated into three sections (basal, middle and distal parts) with the same length of the main stem or primary root. Approximately 80 and 92% of fixed N was distributed in the basal part of the nodulated roots at the vegetative and pod-filling stages by the end of 1 h of ¹⁵N₂ exposure, respectively. In addition, about 90% of fixed ¹⁵N was retained in the nodules and 10% was exported to root and shoot after 1 h of ¹⁵N₂ exposure at 91 DAP. The percentage distribution of ¹⁵N in the nodules at the pod-filling stage decreased from 90% to 7% during the 7 h of the chase period, and increased in the roots (14%), stems (54%), leaves (12%), pods (10%) and seeds (4%). The ¹⁵N distribution was negligible in the distal root segment, suggesting that N fixation activity was negligible and recycling fixed N from the shoot to the roots was very low in the initially short time of the experiment.     

Characterisation of proteins in the storage organs of Curcuma alismatifolia Gagnep.

Summary

Curcuma alismatifolia rhizomes are exported to world markets for ornamental use. Rhizome size and the number of storage roots affected shoot sprouting, plant growth, and inflorescence yield and quality, indicating an important role for storage food reserves such as the carbohydrates and proteins in these organs. An understanding of the proteins used for growth and development in rhizomes and in storage roots is lacking, so changes in the storage proteins in these organs were investigated at the planting stage, the sprouting stage, the second-leaf stage, the flowering stage, and the dormancy stage. The protein concentrations in both these organs decreased rapidly until the flowering stage in order to support the initial growth of roots and shoots. The intensity of Coomassie Brilliant Blue staining of tissues was stronger in rhizomes than in storage roots. Protein staining was present in the cytosol and in the cell walls in rhizomes, and was intense in small particle-like protein bodies in the cytosol. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) profiles showed that peptides of 10.6 kDa and 12.0 kDa were the two major soluble proteins in rhizomes and were different from the proteins in storage roots.The 10.6 kDa and 12.0 kDa bands contained five peptides and one peptide, respectively, when separated by 2D-PAGE. The amino acid sequences of these six peptides were not homologous to any known proteins using BLASTP or FASTA analysis. The N-terminal amino acid sequences of these two polypeptides did not start with methionine, indicating that they had undergone posttranslational modification. Knowledge of the major storage proteins in the rhizomes and storage roots of C. alismatifolia may provide information to improve N-fertilisation.