Enzyme-linked immunosorbent assay using solubilised antigen for detection of antibodies toAnaplasma marginale

An enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies against Anaplasma marginale. A marginale bodies were separated from parasitised erythrocytes by a modified nitrogen decompression method, sonicated, then solubilised with Triton X-100 and used as the ELISA antigen. In this ELISA system the required amount of antigen protein was 16.2 ng for each well. In the course of experimental infections, of calves, significant antibody levels were detected by ELISA and the complement fixation test (CFT) at almost the same time. Antibodies against A. marginale were detectable for longer periods using the ELISA than using the CFT. Sera from calves infected with Babesia bigemina, B. bovis, B. ovata, Theileria sergenti and Eperythrozoon wenyoni gave no reaction; however, antisera against A. centrale did react with the A. marginale ELISA antigen.     

Comparative studies on the photosynthesis of higher plants

1) CO₂ compensation points of the plants tested correlate well with the leaf anatomy. Low CO₂ compensation plants had well-developed VBS containing large and specialized chloroplasts but no plant with a high CO₂ compensation point possessed chloroplasts in the VBS.

2) CO₂ Compensation Points Closely Correlated With The Major Carboxylation Pathway In Photosynthesis. Low Compensation Plants Fixed CO₂ Via The C-4 Pathway (C-4 Plants) While High Compensation Plants Carried Out CO₂ Fixation By The Calvin Cycle (C-3 Plants).

3) Close correlations could be established for the CO₂ compensation point, the major carboxylation pathway, and glycolate oxidase activity. Glycolate oxidase activity was much higher in C-3 plants than in C-4 plants. On the other hand, dark respiration in C-4 plants was higher than that in C-3 plants.

4) TCA cycle activity in detached leaves was not inhibited to any large extent by illumination.

In C-3 plants, the release of ¹⁴CO₂ from alanine-1-¹⁴C increased with an increase in the ambient O₂ concentration; whereas, radioactivity in the sugar fraction was quite small at all O₂ concentrations. In C-4 plants the release of ¹⁴CO₂ was little affected by the ambient O₂ concentration while sugar formation was stimulated at high O₂ concentrations. This indicates that in C-3 plants CO₂ fixation is blocked at a high O₂ concentration, therefore, internal ¹⁴CO₂ is released from the leaf without being refixed, but in C-4 plants internal ¹⁴CO₂ can be efficiently refixed and metabolized to sugar by a combination of active PEP carboxylase and the ‘Kranz type’ of leaf anatomy.     

Degradation of diphenyl ether herbicides in soils

The gas chromatographic determination of CNP (2,4,6-trichlorophenyl 4-nitrophenyl ether), nitrofen (2,4-dichlorophenyl 4′-nitrophenyI ether), chlomethoxynil (2,4-dieblorophenyl 3′-methoxy-4′-nitrophenyl ether), CFNP (2,4-dichloro-6-fluorophenyl 4-nitrophenyl ether) and their amino derivatives in soils were carried out. Good recoveries from soils were obtained for the diphenyl ethers. On the other hand, satisfactory recoveries from soils were also obtained for the amino derivatives at high concentrations, but the recoveries at lower concentrations averaged about 66% for the least recovered compound.

The degradation of several diphenyl ether herbicides in two paddy soils were compared under flooded and upland conditions. The degradation was much slower under upland than under flooded conditions. Considerable amounts of their amino derivatives were produced in soils under flooded conditions, but not under upland conditions. It was suggested that the diphenyl ethers to the amino derivatives involved both chemical and microbial processes. CNP and chlomethoxynil degraded faster at lower concentrations than at higher ones.     

Degradation products of chlomethoxynil (X-52) in soil

The degradation of unlabelled and ^l4C-labelled chlomethoxynil (2,4-dichlorophenyl 3′-methoxy-4′-nitrophenyl ether) in a flooded soil was studied in the laboratory, using thin-layer chromatography (TLC) and combined gas chromatography-mass spectrometry (GC-MS).

Chlomethoxynil was rapidly degraded, and labelled chlomethoxynil was largely transformed into substances which were unextractable with organic solvents. Moreover, most of the radioactive substances extracted with organic solvents were not “free” compounds but complexes. The degradation products identified were the amino derivative (2,4-dichlorophenyl 4′-amino-3-methoxyphenyl ether), the demethyl derivative (2,4-dichlorophenyl 3′-hydroxy-4′-nitrophenyl ether), the formylamino derivative (2,4-dichlorophenyl 4-formylamino-3′-methoxyphenyl ether), the acetylamino derivative (2,4-dichlorophenyl 3-methoxy-4′-acetylaminophenyl ether), thepropionylamino derivative (2,4-dichlorophenyl 4-propionylaminophenyl ether), 2,4-dichlorophenol, and several other minor compounds.     

Reverted glutathione S-transferase-like genes that influence flower color intensity of carnation (Dianthus caryophyllus L.) originated from excision of a transposable element

A glutathione S-transferase-like gene, DcGSTF2, is responsible for carnation (Dianthus caryophyllus L.) flower color intensity. Two defective genes, DcGSTF2mu with a nonsense mutation and DcGSTF2-dTac1 containing a transposable element dTac1, have been characterized in detail in this report. dTac1 is an active element that produces reverted functional genes by excision of the element. A pale-pink cultivar ‘Daisy’ carries both defective genes, whereas a spontaneous deep-colored mutant ‘Daisy-VPR’ lost the element from DcGSTF2-dTac1. This finding confirmed that dTac1 is active and that the resulting reverted gene, DcGSTF2rev1, missing the element is responsible for this color change. Crosses between the pale-colored cultivar ‘06-LA’ and a deep-colored cultivar ‘Spectrum’ produced segregating progeny. Only the deep-colored progeny had DcGSTF2rev2 derived from the ‘Spectrum’ parent, whereas progeny with pale-colored flowers had defective forms from both parents, DcGSTF2mu and DcGSTF2-dTac1. Thus, DcGSTF2rev2 had functional activity and likely originated from excision of dTac1 since there was a footprint sequence at the vacated site of the dTac1 insertion. Characterizing the DcGSTF2 genes in several cultivars revealed that the two functional genes, DcGSTF2rev1 and DcGSTF2rev2, have been used for some time in carnation breeding with the latter in use for more than half a century.     

Variation of indole acetic acid (IAA) amounts in cambial-region tissues in 7- and 24-year-old sugi (Cryptomeria japonica) trees

Recently, breeding programs have attempted to produce high growth rates for shorter rotation cycles in plantation trees. In these trees, the ratio of juvenile wood increases; thus, the juvenile wood properties should be improved for structural use. To this end, it is important to understand the influences on juvenile wood properties precisely. In this study, we report on the indole acetic acid (IAA) amounts of juvenile sugi (Cryptomeria japonica) trees in September and compare the IAA amounts to those in mature trees. The IAA amounts at the lower trunks in juvenile trees were significantly larger than those in mature trees and the IAA amounts decreased with tree height. In each stand, except a mature tree stand, there is no significant effect of IAA amounts on latewood width and MFA. However, put together all samples, the latewood width and MFA increased with IAA amounts in samples with IAA <200 ng/cm². The samples at lower trunk in juvenile trees had significantly larger IAA amounts, larger MFA and larger latewood width than the samples in mature trees (p < 0.01). The very large IAA amounts may have a certain relation with juvenile wood properties.     

Genetic studies of speciation in cultivated rice. 5. Inter- and intraspecific differentiation in the waxy gene expression of rice

Summary To get an insight in the gene regulation at the waxy locus of rice, the Wx gene product (Wx protein) controlling the synthesis of amylose was examined by electrophoretic techniques. Among nonwaxy rice strains, two different alleles, Wx ^a and Wx ^b, were found at the waxy locus. Wx ^a drastically enhanced the quantitative level of Wx protein as well as the amylose content in endosperm starch as compared with Wx ^b. The alleles acted additively in triploid endosperms. This implies that regulatory elements responsible for the Wx gene expression are on the same chromosome. The distribution patterns of Wx ^a and Wx ^b in five species of Oryza revealed that the regulatory changes are closely related to racial differentiation within a common rice species (O. sativa), suggesting that Wx ^b might have been selected for through the difference in grain quality during domestication.     

Temporal stability of multivariate genetic divergence in cacao ( Theobroma cacao L.) in Southern Bahia conditions

Stability of the genetic divergence among five non-commercial cacao cultivars at advanced ages was investigated over a five-year period (1986–1990). Cluster analysis was performed on five yield components measured on harvests from each crop year and on the data pooled over five years. The temporal stability was assessed by using clustering procedure, which involved the calculation Mahalanobis distance (D²) and of Tocher's algorithm applied to the distance matrix. The comparison of D² and of clusters based upon pooled analysis, and taken as the standard, with D² values and clusters obtained from each year showed a stable clustering pattern in the most favourable year. For the rest of the years, inconsistency in number and composition of clusters formed was observed. An optimum environment was shown to be important for better expressing divergence by D². Consequently, the evaluation of the genetic divergence among the studied cultivars may be conducted based on a single favourable year. This will result in considerable savings in man power, financial resources, and time which would be wasted should the evaluation be extended for several years.