Coccidia of the Leporidae*

Thirty-six species of coccidia, all members of the genus Eimeria, have been described from 3 of the 9 genera and 11 of the more than 48 species in the lagomorph family Leporidae. All these are described briefly in the present paper and their synonymies are given. Coccidia have been described from the single species of Oryctolagus, from 4 of the 13 species of Sylvilagus and from 6 of the 26 species of Lepus. These genera have 12, 12, and 14 known species of Eimeria, of which only 2 are shared by Oryctolagus and Sylvilagus. Lepus has none of the coccidia of these genera. One species is known to occur in the bile ducts of the liver, 13 in the intestine, and the location of 22 is unknown. Life cycles have been determined for 9 of the species, of which 8 have been worked out in the domestic rabbit Oryctolagus and 1 in the cottontail Sylvilagus.     

Accessing and exploiting genes of breeding value of distant relatives of crop Brassicas

The Brassicas are an important group of crops in India yielding edible oils and many vegetables. For improving cultivated Brassicas, the wild relatives are of considerable value. The Brassica group of seed oil and vegetables comprises six cultivated species, out of which three are diploids and three are digenomic tetraploids. Brassica juncea is the major seed oil crop in India which can be improved for several traits by incorporating genes from its distant relatives. The early work in India relating to genome manipulation consisted of synthesis of B. juncea by crossing B. campestris with B. nigra, experimental resynthesis of Brassica species and non-homologous pairing and genetic exchange at the interspecific level. The alloploid species B. napus and B. carinata have not been successful in India due to agrometereological limitations. However, synthetic forms of B. napus have been produced which have a desirable maturity period with good yield potential. Also, through non-homologous pairing, pod shatter resistant B. napus has been obtained, B. napus ordinarily suffers from pod shattering. Similarly, synthetic forms of B. carinata have been derived from reciprocal crosses between morphotypes of B. oleracea and B. nigra and also through protoplast fusion of B. nigra with B. oleracea. Molecular analysis has revealed that one of the somatic hybrids had a novel cytoplasmic combination which carried B. nigra mitochondrial and B. oleracea chloroplast genomes. A range of wild and weedy species related to crop Brassicas possess extensive genetic variability. Work for utilizing this variability included hybridization between wild and crop species, analysis of chromosome pairing and induction of alloploidy. Among Brassicas of interest to India, protoplast culture and regeneration has been successful in the case of B. oleracea, B. juncea, B. nigra and B. carinata (cultivated species) and Eruca sativa and Diplotaxis muralis (related wild species). Polyethylene glycol mediated protoplast fusion has been the most commonly used method in India for producing somatic hybrids involving Brassicas. The eight somatic hybrids produced and studied showed that in the majority of cases the fusions led to symmetric hybrids combining the complete genomes of the donor species. For developing suitable male sterile lines, B. juncea, B. campestris and B. napus nuclei have been combined with the cytoplasm of six wild species and stable male steriles have been developed. Protoplast fusion methodology has been used extensively for improving these CMS by manipulating cytoplasmic organelles, including production of new combinations of cp and mt.     

The use of transgenic plants to understand transposition mechanisms and to develop transposon tagging strategies

This review compares the activity of the plant transposable elements Ac, Tam3, En/Spm and Mu in heterologous plant species and in their original host. Mutational analysis of the autonomous transposable elements and two-element systems have supplied data that revealed some fundamental properties of the transposition mechanism. Functional parts of Ac and En/Spm were detected by in vitro binding studies of purified transposase protein and have been tested for their importance in the function of these transposable elements in heterologous plant species. Experiments that have been carried out to regulate the activity of the Ac transposable element are in progress and preliminary results have been compiled. Perspectives for manipulated transposable elements in transposon tagging strategies within heterologous plant species are discussed.     

Comparative organic growth factor requirements of nine Candida species

Nine Candida species isolated from fleshy fruits have been examined for their organic growth factor requirements. Complete or partial deficiencies for thiamine, biotin, pyridoxine, inositol, pantothenic acid, ascorbic acid and xanthine have been reported in C. catenuclta, C. curiosa, C. curvata, C. humicola, C. rhagii, C. steatolytica and C. tropicalis. Only two species, namely, C. fragicola and C. ishiwadea were prototrophic for the growth factors. Concentrations of essential growth factors higher than the optimum have been found inhibitory for the growth of yeasts.     

Low genetic diversity as revealed by SPAR methods possibly leads to extinction of two critically-endangered and endemic species of Mantisia

Mantisia spathulata Schult. and M. wengeri Fischer, two critically-endangered, endemic and rare species of the genus Mantisia (Zingiberaceae), have been rediscovered from Lunglei province of Mizoram, India, after two decades. For sustainable conservation and utilization of the Mantisia species, in vitro seed and clonal propagation methods have been developed earlier by our research group and plantlets have been reintroduced to their natural habitat for species recovery. To comprehend the plausible reasons for endemism and endangeredness of both the species at DNA level, they were analyzed to assess natural genetic variation using three different polymerase chain reaction (PCR) based DNA markers viz. random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR) and directed amplification of minisatellite DNA regions (DAMD), both individually and cumulatively, which are popularly regarded as single primer amplification reaction (SPAR) methods. A total of 107 primers belonging to three SPARs are used which collectively endow low genetic variation (15 and 20 %, respectively) in both M. spathulata and M. wengeri. The use and efficacy of SPAR methods to reveal the natural genetic variation in Mantisia species at intra-specific level has been recorded for the first time. To impede the extinction risk of these two species of genus Mantisia, large scale conservation strategies including in situ and ex situ conservation are recommended.     

Phylogeny of Klebsormidium (Kelbsormidiales; Charophyta) Based on rbcL,atpB, coxIII and nad5 Sequence Data

The charophycean order Klebsormidiales consists of two unbranched filamentous lineages, the fresh water Entransia and the semiterrestrial Klebsormidium. Molecular data have supported the close relationship Klebsormidiales have with land plants. A monograph exists for the European species of Klebsormidium; this monograph provides a cladistic analysis of morphological characteristics for eight Klebsormidium species, but a species level molecular phylogenetic analysis has not yet been performed for the group. We have obtained 50 strains of Klebsormidium, representing 11 morphological species, both from nature and from culture collections. Phylogenetic analyses using rbcL, atpB, coxIII and nad5 gene sequence data from these strains and 40 outgroup sequences suggest that several traditional Klebsormidium species may not be monophyletic.     

Species distribution profiles of the neotropical orchids Masdevallia and Dracula (Pleurothallidinae,Orchidaceae); implications for conservation

The orchid genera Masdevallia and Dracula bear very strange and bizarre flowers. They are, however, very popular with plant enthusiasts and there is a fair amount of commercial trade in these genera. The genera belong to a sub-tribe of the orchids, the Pleurothallidinae, which otherwise mostly have small and insignificant flowers. The majority of the species of Masdevallia and Dracula have been reported from single localities and approximately two thirds of all species are found at three or fewer sites. Most genera in the sub-tribe have similar distribution patterns. Using published deforestation rates and species distribution profiles we calculate that 402 of the total 3405 pleurothallid species may have been driven to extinction by random deforestation events. It is possible that as many as 46 Masdevallia species and 14 Dracula species have already been lost and that annual extinction rates for the two genera are 1 and 0.3 species per year respectively. It has been suggested that the two genera should be protected, by listing them in CITES Appendix I. It is unlikely that embargoes on trade would change extinction rates caused by forest conversion. Such embargoes might actually hamper ex situ conservation efforts.     

Genetics of naphthalene and phenanthrene degradation by Comamonas testosteroni

Naphthalene and phenanthrene have long been used as model compounds to investigate the ability of bacteria to degrade polycyclic aromatic hydrocarbons. The catabolic pathways have been determined, several of the enzymes have been purified to homogeneity, and genes have been cloned and sequenced. However, the majority of this work has been performed with fast growing Pseudomonas strains related to the archetypal naphthalene-degrading P. putida strains G7 and NCIB 9816-4. Recently Comamonas testosteroni strains able to degrade naphthalene and phenanthrene have been isolated and shown to possess genes for polycyclic aromatic hydrocarbon degradation that are different from the canonical genes found in Pseudomonas species. For instance, C. testosteroni GZ39 has genes for naphthalene and phenanthrene degradation which are not only different from those found in Pseudomonas species but are also arranged in a different configuration. C. testosteroni GZ42, on the other hand, has genes for naphthalene and phenanthrene degradation which are arranged almost the same as those found in Pseudomonas species but show significant divergence in their sequences. Received 10 August 1997/ Accepted in revised form 15 August 1997     

Evaluating the feasibility of using candidate DNA barcodes in discriminating species of the large Asteraceae family

Background  

Five DNA regions, namely, rbcL, matK, ITS, ITS2, and psbA-trnH, have been recommended as primary DNA barcodes for plants. Studies evaluating these regions for species identification in the large plant taxon, which includes a large number of closely related species, have rarely been reported.     

Drosophila parasitoids (Hymenoptera) of Japan

The Drosophila parasitoid system is an excellent model for the study of biological and ecological interactions. In Japan, extensive studies have been carried out on Drosophila parasitoids since the early 2000s. Here we provide up-to-date information on their diversity, distributions, host use and reproductive mode. Until now, 45 wasp species have been recorded. In addition, four genetically distinct groups (tentatively assigned as “races”) have been found in Ganaspis brasiliensis (Figitidae). Most of them are larvo-pupal parasitoids belonging to the families Figitidae and Braconidae, and some are pupal parasitoids of the families Pteromalidae and Diapriidae. A species of Encyrtidae was also recorded. Their major hosts are indicated with information on the host's breeding sites. Except Ganaspis xanthopoda and two races of G. brasiliensis that are distributed both in tropical and temperate regions, they are divided into tropical and temperate species. The tropical species are mainly distributed in Southeast Asia, and their distributions in Japan are restricted to the Ryukyu islands, particularly Iriomote-jima. The temperate species have been recorded from the main islands of Japan and surrounding islands but not from the Ryukyu islands, except two braconid species, Asobara japonica and Phaenocarpa sp. TK1. Some of the temperate species have also been recorded from Korea, China, Europe and/or North America. Among the 45 Japanese parasitoid species, at least seven are assumed to be thelytokous.     

The cytology of the genus Briza L. (Gramineae)

Meiosis has been studied in five European and four South American species of Briza. The various species have different chiasma frequencies and different patterns of chiasma localisation. Population studies show that there are significant differences in mean plant chiasma frequency between populations of B. maxima whereas B. media and B. spicata do not show interpopulation differences. B. media is shown to have diploid and autotetraploid races and the distribution of these chromosome races in Europe has been plotted. The South American species studied are all bivalent forming tetraploids and would therefore appear to have an allopolyploid origin. Interchange heterozygosity has been found in B. media and B. elatior, different populations of B. media have been shown to be heterozygous for different interchanges. These topics are discussed in relation to the regulation of recombination.     

Ecology of rotifers of Surinsar,a subtropical,fresh water lake in Jamme (J & K), India

17 species of rotifers have been recorded from Lake Surinsar, Jammu (J & K), India of which some are either exclusively limnetic (Brachionus angularis, Hexarthra sp., Filinia opliensis), or littoral (Brachionus patulus, M. ventralis, Trichotoria sp., Platyias quadricornis, Lecane (Monostyla) decipiens, L (M), bulla and Lecane sp.) and others (Keratella tropica, Anuraeopsis fissa, Brachionus quadridentatus, B. calyciflorus, Trichocera sp., T. similis, and Polyarthra sp.) seem to be wandering species. Seasonal maxima for both littoral and limnetic zones are reported. Most population maxima are contributed mainly by one or at best two species.Physico-chemical factors like temperature, pH, dissolved oxygen, free carbon dioxide, calcium, magnesium, and total alkalinity have been studied and their infuence on these rotifer species are discussed. On their thermal responses, the available rotifer species have been classified as warm stenothermal, cold stenothermal or eurythermal. The importance of Mytilina ventralis as a biological indicator for dissolved oxygen in this lake has been pointed out.     

The decline of the native fishes of lakes Victoria and Kyoga (East Africa) and the impact of introduced species,especially the Nile perch,Lates niloticus,and the Nile tilapia,Oreochromis niloticus

Synopsis There has been a decline, and in some cases an almost total disappearance, of many of the native fish species of lakes Victoria and Kyoga in East Africa since the development of the fisheries of these lakes was initiated at the beginning of this century. The Nile perch, Lates niloticus, a large, voracious predator which was introduced into these lakes about the middle of the century along with several tilapiine species, is thought to have caused the reduction in the stocks of several species. But overfishing and competition between different species also appear to have contributed to this decline. By the time the Nile perch had become well established, stocks of the native tilapiine species had already been reduced by overfishing. The Labeo victorianus fishery had also deteriorated following intensive gillnetting of gravid individuals on breeding migrations. L. niloticus is, however, capable of preying on the species which haven been overfished and could have prevented their stocks from recovering from overfishing. L. niloticus is also directly responsible for the decline in populations of haplochromine cichlids which were abundant in these lakes before the Nile perch became established. Even without predation by Nile perch, it has been shown that the haplochromine cichlids could not have withstood heavy commercial exploitation if a trawl fishery had been established throughout Lake Victoria. Their utilisation for human food has also posed some problems. The abundance of the native tilapiine species may also have been reduced through competition with introduced species which have similar ecological requirements. At present, the Nile perch and one of the introduced tilapiine species, Oreochromis niloticus, form the basis of the fisheries of lakes Victoria and Kyoga.Invited editorial     

Factors influencing <Emphasis Type="Italic">Agrobacterium</Emphasis>-mediated transformation of monocotyledonous species

Summary Since the success of Agrobacterium-mediated transformation of rice in the early 1990s, significant advances in Agrobacterium-mediated transformation of monocotyledonous plant species have been achieved. Transgenic plants obtained via Agrobacterium-mediated transformation have been regenerated in more than a dozen monocotyledonous species, ranging from the most important cereal crops to ornamental plant species. Efficient transformation protocols for agronomically important cereal crops such as rice, wheat, maize, barley, and sorghum have been developed and transformation for some of these species has become routine. Many factors influencing Agrobacterium-mediated transformation of monocotyledonous plants have been investigated and elucidated. These factors include plant genotype, explant type, Agrobacterium strain, and binary vector. In addition, a wide variety of inoculation and co-culture conditions have been shown to be important for the transformation of monocots. For example, antinecrotic treatments using antioxidants and bactericides, osmotic treatments, desiccation of explants before or after Agrobacterium infection, and inoculation and co-culture medium compositions have influenced the ability to recover transgenic monocols. The plant selectable markers used and the promoters driving these marker genes have also been recognized as important factors influencing stable transformation frequency. Extension of transformation protocols to elite genotypes and to more readily available explants in agronomically important crop species will be the challenge of the future. Further evaluation of genes stimulating plant cell division or T-DNA integration, and genes increasing competency of plant cells to Agrobacterium, may increase transformation efficiency in various systems. Understanding mechanisms by which treatments such as desiccation and antioxidants impact T-DNA delivery and stable transformation will facilitate development of efficient transformation systems.     

Diversity of Rhizobium-Phaseolus vulgaris symbiosis: overview and perspectives

Common bean (Phaseolus vulgaris) has become a cosmopolitan crop, but was originally domesticated in the Americas and has been grown in Latin America for several thousand years. Consequently an enormous diversity of bean nodulating bacteria have developed and in the centers of origin the predominant species in bean nodules is R. etli. In some areas of Latin America, inoculation, which normally promotes nodulation and nitrogen fixation is hampered by the prevalence of native strains. Many other species in addition to R. etli have been found in bean nodules in regions where bean has been introduced. Some of these species such as R. leguminosarum bv. phaseoli, R. gallicum bv. phaseoli and R. giardinii bv. phaseoli might have arisen by acquiring the phaseoli plasmid from R. etli. Others, like R. tropici, are well adapted to acid soils and high temperatures and are good inoculants for bean under these conditions. The large number of rhizobia species capable of nodulating bean supports that bean is a promiscuous host and a diversity of bean-rhizobia interactions exists. Large ranges of dinitrogen fixing capabilities have been documented among bean cultivars and commercial beans have the lowest values among legume crops. Knowledge on bean symbiosis is still incipient but could help to improve bean biological nitrogen fixation.     

Hormographiella verticillata and an Ozonium stage as anamorphs of Coprinellus domesticus

Living cultures of Hormographiella verticillata and Coprinellus domesticus, as well as herbarium specimens of Ozonium spp. have been examined and compared. Based on morphological and molecular data, we present for the first time C. domesticus as a teleomorphic stage of H. verticillata and a first record of H. verticillata isolated from human skin in America (Panama). In addition to Hormographiella, species of Ozonium have been described as anamorphic stages of species of Coprinus s.l. Based on extensive review of the literature and own observations, we propose to apply the names Hormographiella spp. to conidiogenous stages of species of Coprinus s.l. and Ozonium stage to the sterile brown hyphae which can be observed in nature and in older cultures of species of Hormographiella. Because species of Ozonium are not distinguishable morphologically, we do not use species names in this genus. The two imperfect stages represent synanamorphs which are designated explicitly for a species of Coprinus s.l. for the first time.     

New data on the flora of diatom algae (Centrophyceae) in waterbodies of Sakhalin Island

The first studies of phytoplankton in inland waterbodies of Sakhalin Island by electron microscopy have revealed 19 representatives of the class Centrophyceae, including some that are new for the flora of the region (Aulacoseira subarctica, Coscinodiscopsis commutata, Stephanodiscus delicatus, S. makarovae, Thalassiosira baltica, and T. cf. hyalina). Species of centric diatoms that are new for these waterbodies have been documented in lakes Vavaiskiye and Tunaicha, and the species composition of Centrophyceae have been revised. The first complete data on the taxonomical spectrum of Centrophyceae in Lake Sladkoye, lakes of Mount Spamberg, and the Tym River have been obtained. A revision of the species composition of Centrophyceae in the waterbodies of Sakhalin Island has been made, and the list of the class has been broadened to 44 taxa from 17 genera.