Developmental morphology of the ovules of Amborella trichopoda (Amborellaceae) and Chloranthus serratus (Chloranthaceae)

The developmental morphology of the outer integument in the pendent orthotropous ovules of Amborella trichopoda (Amborellaceae) and Chloranthus serratus (Chloranthaceae) was studied. In both species the outer integument is semiannular at an early stage and becomes cup-shaped but dorsiventrally somewhat asymmetric at later stages. The outer integument, which is initiated first on the concave and lateral sides of the ovule, differs from that of the anatropous ovules of other basal families with the outer integument semiannular at an early stage or throughout development. The bilateral symmetry of the outer integument is shared by these orthotropous and anatropous ovules. The developmental pattern of the outer integument and ovule incurving characterize the ovule of the Amborellaceae and Chloranthaceae, which is not equivalent to typical orthotropous ovules of eudicots. A phylogenetic analysis of ovule characters in basal angiosperms suggests that anatropous ovules with cup-shaped outer integuments and orthotropous ovules were derived independently in several clades and that the ovules of Amborella and Chloranthus might also be derivative.     

Isolation and characterization of microsatellite DNA loci for endangered fish,Japanese huchen (Hucho perryi)

Japanese huchen, Hucho perryi, is an endangered fish in Japan. In order to promote a conservation program for this species, it is necessary to evaluate its genetic diversity and population genetics. For this purpose, we designed 15 primers containing dinucleotide microsatellite regions and examined their allelic variation using a total of 23 wild individuals collected from two different localities. Eight loci showed moderate allelic variation ranging from two to four alleles, with expected heterozygosities from 0.043 to 0.548. These markers will be useful for the assessment of genetic variation for this species.     

Effect of Inorganic Phosphate on the Levels of Amino Acids in Suspension-cultured Cells of Catharanthus roseus

The levels of free amino acids in suspension cultures of Catharanthusroseus were monitored for 96 h after stationary-phase cellswere transferred to fresh complete (‘+Pi’)     

Development and diversity of microsatellite markers for endangered species,Morus boninensis Koidz., to establish conservation program

We have developed seven microsatellite markers from an enrichment library of genomic DNA for an endangered species, Morus boninensis. A total of 112 of the 320 clones were found to have unique sequences with microsatellite repeats. Seven of 54 primer pairs revealed clear chromatograms and polymorphisms among 36 individuals sampled from three of the Bonin Islands. Seven to 17 alleles per locus were detected, and the expected heterozygosity without considering double reduction ranged from 0.429 to 0.819. These findings should be useful for those studying the conservation genetics of M. boninensis.     

PURIFICATION OF GONAD-STIMULATING SUBSTANCE OBTAINED FROM RADIAL NERVES OF THE STARFISH, ASTERIAS AMURENSIS

Purification of starfish gonad-stimulating substance (GSS), which induces shedding of gametes and oocyte maturation, was carried out using lyophilized radial nerves of Asterias amurensis as source material. In the first series of experiments, 1.3 mg of the purified GSS, which induced spawning at a concentration of 0.0096 μg/ml, was isolated from acetone powder of lyophilized radial nerves of 7,360 starfish through several steps of purification procedures consisting of gel-filtrations on Sephadex G–50 and G–25 columns of various sizes and ion-exchange chromatography on DEAE-Sephadex columns by gradient as well as step-wise elution. With this sample, the molecular weight and amino acid composition of GSS were estimated. Another series of experiments, conducted on a similar amount of material with purification procedures which were essentially the same as those of the first series except for employing 2 steps of partition chromatography instead of extensive gel-filtration, gave about 0.1 mg of purified sample which served as material for studies of the amino acid composition and electrophoretic properties of GSS.
The molecular weight of Asterias GSS was found to be about 2,100, as determined with the sedimentation equilibrium method. GSS seemed to consist of the following 22 amino acid residues: aspartic acid (2), threonine (1), serine (6), glutamic acid (1), proline (1), glycine (4), alanine (2), valine (1), isoleucine (1), leucine (1), histidine (1), and ornithine (1). The isoelectric point of GSS was found to be at about pH 4.5 as determined by the isoelectric focusing method.     

Effects of selected insecticides on Diadegma semiclausum（Hymenoptera： Ichneumonidae） and Oomyzus sokolowskii （Hymenoptera： Eulophidae）, parasitoids of Plutella xylostella （Lepidoptera： Plutellidae）

Abstract Field doses of six selected insecticides were tested against the immature (pupae) and mature (adult) stages of Diadegma semiclausum (Hellén) and Oomyzus sokolowskii (Kurdjumov), parasitoids of the diamondback moth, Plutella xylostella (L.). Effects of contact toxicity (direct spraying) of the six insecticides on emergence of parasitoids were found negligible on both species except permethrin which caused 37.5% mortality. All adults of both parasitoid species died 24 hours after exposure to chlorfenapyr, emamectin benzoate and permethrin. In contrast, the three insect growth regulators (IGRs), chlorfluazuron, flufenoxuron and teflubenzuron, were found harmless to both species, and adult mortality of both parasitoid species was 0–16.7%. However, parasitism by the females of both parasitoid species was severely impaired when the females were offered the three IGR diluted solutions for 24 hours. Effects of oral toxicities of the IGRs on longevity of both parasitoids after 12 hours exposure were found to be significantly different between males and females. Compatibility of tested insecticides with D. semiclausum and O. sokolowskii and integration of compatible insecticides with these parasitoids in integrated pest management programs of crucifers are discussed.     

A revision of the genus Trixa Meigen （Diptera： Tachinidae）

The genus Trixa Meigen, 1824 is revised. Dexiotrix Villeneuve, 1936 and Trixella Mesnil, 1980, each of which was sometimes treated as a distinct genus, are treated as junior synonyms of Trixa Meigen. Two species from Sichuan and Yunnan, China, are described as new to science, viz. Trixa chinensis sp. nov. and T. chaoi sp. nov. T. alpina Meigen is treated as a junior synonym of T. caerulescens Meigen. T. nox (Shima) and T.pubiseta (Mesnil) are newly recorded from China. Males of T. pubiseta (Mesnil) and T.longipensis (Villeneuve) are described for the first time. Diagnoses, figures and a key to twelve species in Trixa are given.     

Mode of pollen tube growth in pistils of Ticodendron incognitum (Ticodendraceae,Fagales) and the evolution of chalazogamy

Ticodendron incognitum is the sole species of the Ticodendraceae, which was established as a new family in the Fagales less than 20 years ago. Considering the diverse modes of pollen tube growth observed in other Fagales, we investigated the growth of pollen tubes in the pistil of Ticodendron. At the time of pollination, T. incognitum had four immature ovules in a bilocular ovary, thus exhibiting delayed fertilization, as in other Fagales. During the period when fertilization was delayed, pollen tube growth in the pistil was intermittent, consisting of five steps associated with development of the ovules and embryo sacs. Four cessation sites occurred: in the style, in the tissue of the upper part of the ovary, inside and outside of the funicle and at the chalaza. A single pollen tube eventually reaches a mature embryo sac through the chalaza in one of the four ovules. While both delayed fertilization and intermittent pollen tube growth play a role in male and female gametophyte selection, as in other Fagales, the five‐step process of pollen tube growth through the chalaza (i.e. chalazogamy) is characteristic of lineages of the Casuarinaceae, Ticodendraceae and Betulaceae (the latter with the loss of one step). © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 621–631.