Occurrence of rocket larkspur witches’ broom caused by “<Emphasis Type="Italic">Candidatus</Emphasis> Phytoplasma asteris” in Japan

In October 2001, a disease of rocket larkspur (Cosolida ambigua (L.) P. W. Ball et Heyw), characterized by witches’ broom, yellows and virescence of flowers, was found in Yakage Town in Okayama Prefecture. Electron microscopy revealed the presence of phytoplasma-like bodies in the phloem of diseased plants. The causal phytoplasma was identified as “Candidatus Phytoplasma asteris” based on 16S rDNA sequence analysis, and demonstrated to be acquired by the leafhopper Macrosteles striifrons. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession number AB258330.     

Mineral composition in the holdfast of three brown algae of the genus Laminaria

SUMMARY: The mineral (Na, K, Ca, Mg, Fe, Mn and Zn) contents in the holdfast of three brown algae of the genus Laminaria were determined to compare with those in frond and stipe. The wild and cultivated kelps of Laminaria japonica , L. ochotensis , and L. diabolica were used as samples. The K content was markedly high (11.76–14.91 g/100 g dry weight) in the holdfast of cultivated L. japonica; the K/Na ratio (3.88–5.18) of the holdfast was greater than those of frond and stipe as well as the reported values of frond (1.0–2.2). The content of Ca in the holdfasts of these three species was also higher than those in frond and stipe. The content of Mn showed the same tendency. This is the first report showing that the holdfast of L. japonica and L. diabolica is rich in minerals, especially K.     

Transmission of Rhus (Rhus javanica L.) Yellows by Hishimonus sellatus and Host Range of the Causal Phytoplasma

In 1998, rhus (Rhus javanica L.) yellows (RhY), caused by phytoplasma, was found in Miyagi Prefecture, Japan. In vector transmission tests, Hishimonus sellatus acquired RhY phytoplasma from diseased R. javanica and transmitted it to healthy R. javanica. Twenty-two species of herbaceous plants in 10 families were infected with RhY phytoplasma by H. sellatus. The host range and main symptoms on test plants of RhY phytoplasma differed from those of Macrosteles striifrons-transmitted phytoplasmas, which belong to the same 16Sr I group phytoplasma. Received 6 December 1999/ Accepted in revised form 14 May 2000     

烟草普通花叶病毒在烟草胞质体中的增殖

 本试验证明了TMV-RNA在有细胞核的烟草原生质体中能大量增殖,但在无核的胞质体中却难以增殖。     

Complementary process to response bias in the centromedian nucleus of the thalamus

Activity in several areas of the human brain and the monkey brain increases when a subject anticipates events associated with a reward, implicating a role for bias of decision and action. However, in real life, events do not always appear as expected, and we must choose an undesirable action. More than half of the neurons in the monkey centromedian (CM) thalamus were selectively activated when a small-reward action was required but a large-reward option was anticipated. Electrical stimulation of the CM after a large-reward action request substituted a brisk performance with a sluggish performance. These results suggest involvement of the CM in a mechanism complementary to decision and action bias.     

Total synthesis of norzoanthamine

Norzoanthamine, an alkaloid isolated from Zoanthus sp., can suppress the loss of bone weight and strength in ovariectomized mice. Norzoanthamine derivatives can also strongly inhibit the growth of P-388 murine leukemia cell lines and human platelet aggregation. However, norzoanthamine's densely functionalized complex stereostructure and scarce availability from natural sources have proved a synthetic challenge. We report the stereoselective total synthesis of norzoanthamine in 41 steps, with an overall yield of 3.5% (an average of 92% yield each step).     

Monitoring of the genetic variability of the hatchery and recaptured fish in the stock enhancement program of the rare species barfin flounder <Emphasis Type="Italic">Verasper moseri</Emphasis>

ABSTRACT:   In relation to the stock enhancement program for barfin flounder, hatchery juveniles produced in 2001 were genotyped using microsatellite DNA markers (msDNA) and then released to natural waters. Subsequently, recaptured individuals, designated as 'tentative recaptured', were examined using msDNA. In order to evaluate the effectiveness of the stock enhancement program, pairwise F _ST and genic differentiation tests were used to estimate the genetic divergence between the wild samples, the hatchery broodstock, and the tentative recaptured samples. Analysis showed significant differentiation among these three groups. Pedigree determination by msDNA was used to establish the origin of the tentative recaptured individuals, in order to elucidate whether they were hatchery produced, 'real recaptured', or wild specimens. Wild individuals were not found. The effective population size of the real recaptured stock was very low ( N _e = 16.6). Equal family survivability was observed between the released and real recaptured stocks, indicating that the genetic variability of the released stock was maintained in the natural environment. Future broodstock management, breeding designs, and family contribution equalization of the offspring to be released will be required in this rare species to avoid unintended genetic differentiation between the wild population and the hatchery broodstock.