Enzyme polymorphism and adaptation in strawberry clover (Trifolium fragiferum L.)

Enzymatic survey of eight loci in 22 populations of Trifolium fragiferum L. sampled in three regions in Poland showed regional differences with regard to five genetic parameters describing genetic polymorphism and variability. Differences were attributed to the following climatic variables: annual precipitation, temperature and solar radiation. Continental climatic conditions were favorable for accumulation of genetic polymorphism and variability. Vegetative reproduction versus sexual reproduction had a higher incidence rate under milder climatic conditions. This former mode of reproduction also affected patterns of distribution of variation within regions, by reducing the intra-populational component of total variability.     

Different methods for the evaluation of species of the genus Mesaphorura (Collembola, Tullbergiinae)

Field studies and laboratory investigations based upon cultures, isoenzyme electrophoresis and RAPD-PCR were carried out to get a better understanding of the value of morphospecies within the genus Mesaphorura.Culturing of seven Mesaphorura species under constant as well as variable conditions provided a basis for evaluation of morphological characters, but did not yield any statistically supportable evidence that intraspecific variability reached interspecific delimitations.In enzyme tests, esterases gave the best results. The search for species-specific band patterns is, however, time and material consuming. DNA investigations using RAPD-PCR resulted in band patterns that appeared to be species specific. Nevertheless, these require further investigations.None of the studies carried out gave any conclusive evidence for invalidation of the morphologically defined species of the genus Mesaphorura.     

Reproductive biology and conservation implications of three endangered snapdragon species (Antirrhinum, Plantaginaceae)

About 32% of Antirrhinum species are considered to be endangered; however, no field studies have focused on their reproductive biology. In this work, several aspects of the reproductive biology (flowering phenology, floral biology, breeding system) and potential limits on seed quantity and quality (pollen limitation, inbreeding depression) were studied in natural populations of three endangered species of the genus (Antirrhinum charidemi, Antirrhinum subbaeticum, Antirrhinum valentinum). Results disclose that all three species need insect visitors for seed production since fruit set after autonomous self-pollination was lower than under hand cross-pollination. A. charidemi and A. valentinum were mainly self-incompatible, whereas A. subbaeticum was self-compatible but herkogamous. Supplementary pollination in open-pollinated flowers only increased fruit set and seed set relative to controls in a given population of A. valentinum. Preliminary data on inbreeding depression at early life-cycle stages of the self-compatible A. subbaeticum revealed that the cumulative level was low. Despite the three species being closely related and sharing many ecological characteristics, they show different mating systems, and different factors limit seed quantity and quality. Thus, caution should be taken when making a common conservation plan for a group of closely related taxa.     

Inter-relation between descriptors and morphine yield in Asian germplasm of opium poppy Papaver somniferum

A set of 208 Indian and two Thai germplasm accessions of opium poppy Papaver somniferum were assessed for variation in 17 morphological characters, seed yield and content and yield of morphine from capsules and peduncles. The germplasm was found to be highly variable for all the characters evaluated. In the harvested peduncles and capsules, 13% was peduncle straw, 61% seeds and the rest capsule husk. The peduncle and capsule straw yields ranged between 0.6–2.2 and 1.4–5.3 g plant^-1, respectively. Morphine content in the peduncle varied between about 0.001–0.24% and that in the capsule from 0.02 to 1.05%. On average basis morphine content in the capsule husk was more than 9-fold higher than the peduncle straw. The plant morphine yields from peduncles and capsules ranged between 1.2 and 28.6 mg plant^-1. Four accessions yielded more than 20 mg of morphine plant^-1. Among these, in one of the accessions about 13% of the morphine was contributed by the peduncle. The plants of high morphine yielding accessions were generally small in height, and bore white flowers and large sized ungrooved capsules with a small number of seeds, on a large peduncle.     

Preference of three collembolan species for fruit-bodies of three species of basidiomycete fungi

We examined whether co-existing Hypogastrura species feeding on fruit-bodies show differences in utilization of fruit-bodies, and whether their utilization reflect their preferences for basidiomycete species, by field surveys and bait-trap experiments. In field surveys, the relative densities of the collembolans, Hypogastrura denisana, H. denticulata, and Hypogastrura sp. 1, on the selected basidiomycete species, Cortinarius salor, Lactarius quietus, and Russula emetica, differed significantly between the collembolan species. In bait-trap experiments using fruit-bodies of the three basidiomycete species as bait, the relative densities of the three collembolan species on the basidiomycete species differed significantly between the collembolan species and these differences were similar to the differences observed in the field surveys. These results suggest that the three collembolan species have differential preferences for fruit-bodies of the three selected basidiomycete species, and that the preferences relate to their utilization of fruit-bodies.     

The role of demographic compensation theory in incidental take assessments for endangered species

Many endangered species laws provide exceptions to legislated prohibitions through incidental take provisions as long as take is the result of unintended consequences of an otherwise legal activity. These allowances presumably invoke the theory of demographic compensation, commonly applied to harvested species, by allowing limited harm as long as the probability of the species’ survival or recovery is not reduced appreciably. Demographic compensation requires some density-dependent limits on survival or reproduction in a species’ annual cycle that can be alleviated through incidental take. Using a population model for piping plovers in the Great Plains, we found that when the population is in rapid decline or when there is no density dependence, the probability of quasi-extinction increased linearly with increasing take. However, when the population is near stability and subject to density-dependent survival, there was no relationship between quasi-extinction probability and take rates. We note however, that a brief examination of piping plover demography and annual cycles suggests little room for compensatory capacity. We argue that a population’s capacity for demographic compensation of incidental take should be evaluated when considering incidental allowances because compensation is the only mechanism whereby a population can absorb the negative effects of take without incurring a reduction in the probability of survival in the wild. With many endangered species there is probably little known about density dependence and compensatory capacity. Under these circumstances, using multiple system models (with and without compensation) to predict the population’s response to incidental take and implementing follow-up monitoring to assess species response may be valuable in increasing knowledge and improving future decision making.     

Polymorphism of high molecular weight glutenin subunits in three species of Aegilops

A collection of 136 accessions of Aegilops umbellulata (39), Ae. comosa (75) and Ae. markgrafii (22) was analysed for high-molecular-weight (HMW) glutenin subunits composition. The homogeneity of the accessions was studied and 55.1% of the collection was homogeneous for HMW glutenin subunits (29 Ae. umbellulata, 33 Ae. comosa and 14 Ae. markgrafii). The HMW glutenin subunits of Ae. umbellulata are encoded by the Glu-U1 locus; in Ae. comosa results showed that this proteins are encoded at the 1M chromosome, and the locus was named Glu-M1. In Ae. markgrafii it was assumed that HMW glutenin subunits were encoded by an homoeologous locus and it was named Glu-C1. All the accessions of Ae. umbellulata and Ae. markgrafii expressed both, x-type and y-type subunits. Among the Ae. comosa accessions, only one expressed an x-type subunit alone. All the accessions of Ae. umbellulata and some of Ae. comosa had x-type glutenins of higher molecular weights than those commonly present in bread wheat. A total of 8 alleles were detected at the Glu-U1 locus, 11 at the Glu-M1 and 4 at the Glu-C1. The new HMW glutenin variation found in this work suggests their possible utilisation in breeding for wheat quality.     

Herbicides, weeds and endangered species: management of bitou bush (Chrysanthemoides monilifera ssp. rotundata) with glyphosate and impacts on the endangered shrub, Pimelea spicata

Environmental weed invasion threatens the biodiversity of native species. Unfortunately, managing these weeds may also affect biodiversity adversely. A recent example occurred when glyphosate, a herbicide used to control the highly invasive weed, bitou bush (Chrysanthemoides monilifera ssp. rotundata), accidentally drifted over a small population of an endangered shrub, Pimelea spicata. Following concerns that the affected population would not recover and, thereby, cause the local extinction of P. spicata, we conducted a series of glasshouse and field experiments to explore the impacts of glyphosate on this endangered species. Seedlings and young plants of P. spicata, in which the tap root was undeveloped, were killed by a single application of glyphosate. Older plants with a well developed tap root also died back initially, but about 50% of individuals re-sprouted. This re-growth was associated with a significant decrease in tap root diameter, implying that further disturbance, including repeated treatment with glyphosate, would kill plants by impairing their potential for recovery. Unlike some sclerophyllous native shrubs, the tolerance of P. spicata to glyphosate was limited, even when its growth was slowed artificially by limiting water availability. Winter applications of glyphosate to manage infestations of bitou bush will impact adversely on populations of P. spicata and may also affect the other rare and endangered species whose survival is threatened by this species, even though some natives are unaffected by the herbicide. Protecting native biodiversity from bitou bush will involve sustainable weed management that minimises impacts on non-target native species.     

Isozyme analysis of three species ofRoegneria C. Koch from China

To collect and exploitRoegneria genetic resources, isozyme variation on 7 different enzymes encoded by 26 presumptive loci were analyzed in leaf extracts ofR. kamoji, R. ciliaris, R. nakaii andTriticum aestivum cv. Chinese Spring (control species) using polyacrylamide gel electrophoresis. No isozyme polymorphism was detected within accession of the threeRoegneria species, all having self-pollinating reproduction. However, extensive variations at isozyme loci were observed among accessions ofR. kamoji — even among accessions distributed at different altitudes within the same collection area. These results suggested that: (1) a select few individuals collected at a collection site may be enough to represent the genetic variability of that population; and (2) collection and maintenance ofR. kamoji materials from different altitudes may be required to increase genetic diversity. Furthermore, the banded phenotypes at EST 1 and EST-2 loci may be used as a biochemical marker associated with a morphological character, pubescences covered at leaf margin inR. kamoji. The banded characters at EST- 1, SOD-1, SOD-2, and SOD-3a loci may be used as biochemical markers to identify theR. kamoji chromosomes carrying these loci in aT. aestivum ×R. kamoji hybridization program.     

Diversity of native rice (Oryza Poaceae:) species of Costa Rica

We found several populations of wild Oryza species in the lowlands of Costa Rica. The plants showed extensive morphological variation, suggesting the presence of several species. In the morphologic study, 33 traits were scored for plants of all the species. A principal component analysis revealed the significant morphological separation of the different species. The analyses indicated that there are three species, O. grandi­glumis, O. latifolia and O. glumaepatula. Two putative hybrid types were found, both significantly differing in their morphology from the known species and intermediate at several traits. O. grandi­glumis is a new record for Costa Rican flora. Its main population is located in Caño Negro Wildlife Refuge, Los Chiles, Alajuela. O. latifolia is distributed throughout the lowlands of the country and the plants of the Atlantic slope are significantly bigger in general habit than those of the Guanacaste area. During this study a population of O. glumaepatula of hundreds of thousands of plants was discovered in the Medio Queso River wetland, Los Chiles, Alajuela. This population is the most important source of genes for cultivar's improvement from the primary gene pool of rice in Costa Rica. The small ligule and the wide flag leaf characteristic of the two CCDD species separated them from the AA diploid O. glumaepatula. Seed size, ligule size, number of branches in the panicle, plant height and sterile lemma length are all bigger in O. grandi­glumis, and influenced the second factor that separated the CCDD species in two discrete clusters. The species found offer great possibilities for the improvement of rice cultivars and they should be thoroughly studied and appropriately protected.     

Cytogenetic and systematic analyses of Kengyilia gobicola, K. zhaosuensis and K. batalinii var. nana (Poaceae)

Kengyilia batalinii var. nana J.L. Yang, Yen et Baum, K. gobicola Yen et J.L. Yang, K. zhaosuensis J.L. Yang, Yen et Baum are short-lived perennial grasses of the family Triticeae distributed throughout the upper and middle mountain ranges of west China. They were cytogenetically studied with testers R. kamoji Ohwi (StStHHYY) and K. hirsuta (Keng) J. L. Yang, Yen et Baum (PPStStYY). Analysis of metaphase I pairing configurations in the F₁ indicate that K. batalinii var. nana, K. gobicola, K. zhaosuensis possess the P, St, and Y genomes, with o nly minor structural rearrangements. These results showed that the three target taxa are good species in the genus Kengyilia.     

Relationships of Vigna unguiculata (L.) Walp., V. vexillata (L.) A. Rich. and species of section Vigna based on isozyme variation

Summary Isozyme variation in 25 accessions of wild and cultivated Vigna unguiculata, 49 accessions of seven wild species belonging to section Vigna, and 11 accessions of V. vexillata (subgenus Plectrotropis) was scored at 17 putative loci to assess genetic relationships within and among species. The wild species selected for this study are among those which carry important agronomical traits useful in cowpea (V. unguiculata) breeding programs. Allelic frequencies were calculated and Nei's genetic distances were obtained. Low levels of intraspecific variation were observed for V. heterophylla, V. luteola and V. racemosa, whereas the other species showed a higher polymorphism. Vigna unguiculata possessed intraspecific genetic distances comparable to those previously found by other authors. Most of the isozyme variation was apportioned among species. Although V. luteola and V. marina had an interspecific genetic distance resembling the range observed at intraspecific level, all the other species showed very high interspecific distances. Vigna unguiculata was relatively closer genetically to V. vexillata than to the species belonging to section Vigna.Abbreviations AUS Australia - BDI Burundi - BRA Brazil - BWA Botswana - CAF Central African Republic - GHA Ghana - CMR Cameroon - COG Congo - RI Costa Rica - EGY Egypt - ETE Ethiopia - GAB Gabon - GRC Greece - ITA Italy - KEN Kenya - MOZ Mozambique - NER Niger - NGA Nigeria - PAN Panama - RWA Rwanda - TCD Chad - TZA Tanzania - ZAF South Africa - ZAR Zaire - ZMB Zambia     

Mendeschilis a new genus of Microcoryphia (Insecta, Apterygota, Machilidae) from Spain

A new species and genus of Microcoryphia is described as a result of the detailed comparison of specimens from Italy and Spain which had been initially identified as Praemachilis excelsior. The new genus, named Mendeschilis has as its most important distinctive taxonomic characteristic the presence, in the male, of parameres in the VIII^th and IX^th urosternites, while Praemachilis (from Italy) has only one pair of parameres in the IX^th urosternite. Other anatomical characteristics which allow us to differentiate the new genus and the new species are described.     

Identification of resistant sources in Cicer species to Liriomyza cicerina

Summary Leaf miner (Liriomyza cicerina Rond.) causes considerable damage to chickpea (Cicer arietinum L.) in West Asia, North Africa and Southern Europe. Use of resistant cultivar is the economical method of control. Screening of over 7000 germplasm accessions did not result in identification of highly resistant accessions to this insect. Therefore, 200 accessions of eight wild Cicer species were evaluated in search of resistance to leaf miner between 1988 and 1991 at ICARDA, Syria. Accessions of Cicer species were screened under natural insect infestation in the field during spring (March–June), along with a susceptible-cum-indicator line. Two accessions of C. cuneatum (ILWC-40 and -187) and 10 accessions of C. judaicum (ILWC-44, -46, -56, -57, -58, -95, -103, -196, -206, and -207) were rated 2 on a 1–9 scale, where 1 = free from any damage and 9 = maximum damage. Another 18 lines of C. judaicum, four lines of C. pinnatidum and one line of C. reticulatum were rated 3 (resistant). Currently three species are incompatible in crossing with chickpea, but C. reticulatum is being used in breeding programme.Joint contribution from ICARDA and ICRISAT (Inter-national Crops Research Institute for the Semi-Arid Tropics), Patancheru P.O., AP 502 324, India.     

Differential morphogenetic responses, ginsenoside metabolism and RAPD patterns of three Panax species

Genetic and metabolomic demarcations between two Indian and one American congeners of Genus Panax have been discerned. Genomic DNA was isolated from the root derived callus cultures of these species and amplified by AP-PCR. RAPD analyses of the DNA with six most responding arbitrary oligonucleotide decamers provided a total of 70 reproducible bands for computation of the similarity matrix amongst the Panax species. Only 18 of these were monomorphic giving an estimate of about 74% polymorphism among the test species examined. The similarity coefficient values based on the amplification pattern support an equidistant position of the three test species. The molecular demarcations between the species are also manifested in terms of their characteristic cultural requirements, in vitro growth kinetics, regeneration competence and ginsenoside complement of their calli. The Indian congeners i.e. P. sikkimensis and P. pseudoginseng were distinguishable by higher proportions of ginsenoside Rf and Ro (40% and 20%, respectively) in the crude saponin fractions. Furthermore P. quinquefolium calli mainly accumulated ginsenoside Rb₂ and Rg₁, whilst P. sikkimensis callus was rich in Rd fraction. P. quinquefolium showed high similarity with P. sikkimensis with respect to plasticity and totipotency for somatic embryogeny whereas P. pseudoginseng callus was highly recalcitrant and lacked regenerative capacity. The chemical and genetic fingerprints alongwith morphogenetic responses of the three species under controlled in vitro environment strongly advance the case of P. sikkimensis as an independent species, rather than a conglomerate of location specific variety or sub-species of P. pseudoginseng. The findings are also of relevance to formulations and evaluation of ginseng-based health foods.     

Population dynamics of the earthworm Amynthas alexandri (Annelida: Megascolecidae) in a Kumaun Himalayan pasture soil

Ecological studies on earthworms were conducted in a Kumaun Himalayan pasture soil. The C:N ratio in the soil declined with increasing depth. A combination of hand-sorting and formalin application was used to sample the earthworms. Three species, Amynthas alexandri, A. diffringens (Megascolecidae), and Eisenia fetida (Lumbricidae) were found. Of the 13310 individuals collected, 99.9% were A. alexandri. The maximum density (138.8 m^-2) and biomass (25.2 g m^-2) were recorded in the wet season. More than 60% of the total earthworm numbers and biomass were recorded at 0–10 cm in depth. The mean yearly ratio of clitellate to aclitellate worms was 1:7.3.     

Use of prolamine polymorphism in studying genetic resources of forage grasses

Summary Electrophoresis of single seed prolamines was used for the analysis ofLolium perenne L.,Festuca pratensis Huds., andDactylis glomerata L. populations. Identification and registration of populations was carried out according to the frequencies of occurrence of genotypes with corresponding types of prolamine banding patterns. The publication sums up the problems of applied use of molecular markers for identification and registration of world genetic resources of forage grasses, analysis of the dynamics of population composition and other problems of plant growing, genetics, breeding and seed control. The approaches mentioned in the article are promising for their use in genetic banks as well as at the institutions which store collections of genetic resources of given crops and at universities and breeding stations.     

Factors affecting surface casting behaviour in several species of earthworm

Summary Surface cast production was investigated for several species of earthworms, including some not normally considered to produce surface casts. In single-species culture, the amount of cast material deposited on the surface by different species varied, with Allolobophora chlorotica < Lumbricus rubellus < Aporrectodea caliginosa < Aporrectodea longa. In field communities, results indicated that a single species dominated surface casting activity. The order of species dominance was consistent with the above findings from single-species cultures, if Lumbricus terrestris was considered to be equivalent to Ap. longa.Surface casting is an essential function within earthworm communities which maintains their living space. However, it involves an energy cost and carries a risk of predation. Therefore, there are disadvantages associated with this activity. All of the species studied produced surface casts unless other, usually larger, species were present.