The chemical environment of Salvinia molesta Mitchell: Ionic concentrations of infested waters

Concentrations of major anions and cations and of NO₃N, PO₄P and total dissolved Fe are reported for 6 sites in southeast Queensland, Australia. Samples collected from a lake over 40 weeks showed that concentrations of N, P, K an Fe increase rapidly after rain, then decreased rapidly, probably due to uptake by Salvinia molesta Mitchell. Concentrations of Na, Ca, Cl and HCO₃ increased slowly during a prolonged dry spell and decreased rapidly after heavy rain. Ionic concentrations in the lake and in streams were similar to those reported from waters infested with S. molesta elsewhere. Concentrations in a sewage lagoon were generally far higher, but there were no indications of toxicity. Comparisons with uninfested waters suggest that S. molesta has not yet occupied all Australian freshwaters suitable for it.     

Samea multiplicalis [Lep.: Pyralidae], for biological control of two water weeds,Salvinia molesta andPistia stratiotes in Australia

The biology and host specificity ofSamea multiplicalis (Guenée) were studied in quarantine in Australia. Immature stages completed development onSalvinia molesta Mitchell,Pistia stratiotes L. andAzolla pinnata R.Br. In starvation tests, although larvae which had first fed onS. molesta produced minor leaf scarring on some other plants, they were unable to complete development. Damage toS. molesta andP. stratiotes indicated thatS. multiplicalis may be a valuable biological control agent for these weeds in Australia.S. multiplicalis was first liberated in northern Queensland in 1981 where it has become established onS. molesta.     

Three new species of Neopectinimura Park (Lepidoptera: Lecithoceridae) from Papua New Guinea,Indonesia

Three new species of Neopectinimura Park: N. walmakensis Park, N. trichodes Park and N. devosi Park, are described from Papua New Guinea, Indonesia. The genus Neopectinimura is a derivative of Pectinimura Park, distinguished from the latter by long specialized hairs on the flagellum of the antenna, and is known in Papua New Guinea.     

Suppression of Salvinia molesta Mitchell in Texas and Louisiana by Cyrtobagous salviniae Calder and Sands

Release and evaluation studies of the Brazil population of Cyrtobagous salviniae on Salvinia molesta were conducted originally at 18 sites in Texas and Louisiana from 1999 through 2005. However, overall project results could only be continually evaluated at two release and two control sites because the remainder were eventually destroyed or corrupted by floods, droughts, or herbicides. Mean fresh weight biomass of S. molesta ranged from 15.5 kg FW m⁻² during the summer to as low as 2.1 kg FW m⁻² during the winter prior to the release of C. salviniae. Insect populations established within a year of release and initially spread slowly. Damage to S. molesta increased with increasing C. salviniae detections while S. molesta biomass and surface coverage declined at both release sites by more than 99% while remaining unchanged at the control sites. Water in release sites registered higher levels of dissolved oxygen, higher temperatures, and higher pH than water in control sites. This study provides another example of the effectiveness of C. salviniae against S. molesta even in more temperate climates.     

Musaespora,a genus of pyrenocarpous lichens with campylidia,and other additions to the foliicolous lichen flora of New Guinea

Abstract: The new lichen genus Musaespora is described from Java and Papua New Guinea. It is the first known pyrenocarpous lichen genus with campylidia, and appears to belong to the Aspidotheliaceae. Three species are described, two foliicolous species from Papua New Guinea and one corticolous species from Java. In addition, a list is given of the foliicolous lichen flora of the site in Papua New Guinea, where the foliicolous Musaespora species have been found, two more new foliicolous species are described, Echinoplaca hispida and Sporopodium lucidum, and 19 species are recorded for the first time form Papua New Guinea.     

Characterization and comparison of potential denitrifiers in microbial mats from King George Island,Maritime Antarctica

Cyanobacterial microbial mats are highly structured communities commonly found in Antarctic inland waters including melt streams. These benthic microbial associations comprise a large number of microorganisms with different metabolic capacities, impacting nutrient dynamics where established. The denitrification process is a feasible nitrogen loss pathway and a biological source of nitrous oxide, a potent greenhouse gas that also promotes ozone depletion. Potential denitrifiers from five microbial mats were characterized using a PCR-DGGE (denaturing gradient gel electrophoresis) approach. Molecular markers encoding for key enzymes in the denitrification process (nirK, nirS and nosZ) were used. Fingerprints were obtained for the five sampled mats and compared for two successive years. Distance analysis showed that despite the sampled year, the denitrifying genetic potential was similar between most of the sites when represented in Euclidean space. The number of dominant denitrifiers detected for each sample ranged between 6 and 18 for nirK, 4–10 for nirS and 6–17 for nosZ. The seventy-two sequenced phylotypes showed 80–98 % identity to previously reported environmental sequences from water column, sediments and soil samples. These results suggest that Antarctic microbial mats have a large denitrification potential, previously uncharacterized and composed by both site-specific and common phylotypes belonging mainly to Alpha-, Beta- and Gammaproteobacteria.     

Equations relating growth and uptake of nitrogen by Salvinia molesta to temperature and the availability of nitrogen

Equations for predicting rates of growth, nitrogen content and rates of nitrogen uptake in Salvinia molesta Mitchell were derived from the literature and from new experiments. Equations for the effects of temperature specified zero growth below 5°C and above 43°C, with an optimum at 30°C and are applicable over a wider range than an Arrhenius model. They explained 74 and 55% of the variance in growth in numbers of leaves and weight, respectively, in a sewage lagoon where nutrients should not have been limiting. Equations for the effects of nitrogen content of the plant specified a four-fold, asymptotic increase in growth between 0.8% N and maximum growth above 5.0% N. Predictions from nitrogen contents explained 41% of the variance in growth in numbers of leaves in Papua New Guinea where temperatures fluctuated little. Top: root ratios rose from near 1.5 at 1% N to near 6.0 at 5% N. Rates of nitrogen uptake followed trends similar to rates of growth and nitrogen fixation supported a low rate of growth in the absence of nitrogen in solution.     

Multilocus population genetic analysis of the Southwest Pacific malaria vector Anopheles punctulatus

The population structure and history of the cryptic malaria vector species, Anopheles punctulatus (Doenitz), was investigated throughout Papua New Guinea and the Solomon Islands with the aim of detailing genetic subdivisions and the potential for movement through this biogeographically complex region. We obtained larval collections from over 80 sites and utilised a diverse array of molecular markers that evolve through different processes. Individuals were initially identified to species and genotyped using the ribosomal DNA second internal transcribed spacer. DNA sequencing of a single copy nuclear ribosomal protein S9 and the mitochondrial cytochrome oxidase I loci were then investigated and 12 nuclear microsatellite markers were developed and analysed. Our data revealed three genetically distinct populations – one in Papua New Guinea, the second on Buka Island (Bougainville Province, Papua New Guinea), and the third on Guadalcanal Island (Solomon Islands). Genetic differentiation within Papua New Guinea was much lower than that found in studies of other closely related species in the region. The data does suggest that A. punctulatus has undergone a population bottleneck followed by a recent population and range expansion in Papua New Guinea. Humans and regional economic growth may be facilitating this population expansion, as A. punctulatus is able to rapidly occupy human modified landscapes and traverse unsealed roads. We therefore anticipate extensive movement of this species through New Guinea – particularly into the highlands, with a potential increase in malaria frequency in a warming climate – as well as relatively unrestricted gene flow of advantageous alleles that may confound vector control efforts.     

The Strongylophthalmyiidae (Diptera) of Papua New Guinea,with descriptions of five new species and a world checklist

Eight species of the Strongylophthalmyiidae are reported from Papua New Guinea. Of these, five species (Strongylophthalmyia gigantica sp. nov., S. papuana sp. nov., S. rubella sp. nov., S. sedlaceki sp. nov. and S. shatalkini sp. nov.) are described as new to science. Strongylophthalmyia puncticollis Frey is recorded for the first time from Papua New Guinea. Faunistic remarks, a key to the species of the Strongylophthalmyia in Papua New Guinea and a world checklist are provided.     

Paraplagusia longirostris,a new flatfish (Cynoglossidae) from Australia and Papua New Guinea

A new species of tongue sole,Paraplagusia longirostris, is described from 59 specimens (83.0– 276.2 mm SL) collected off the northern coast of Australia and southern coast of Papua New Guinea.P. longirostris is easily distinguishable from otherParaplagusia by its long, obtusely pointed snout and its high counts for dorsal and anal fin rays, caudal vertebrae and mid-lateral line scales.     

LICHENICOLOUS FUNGI FROM THE WESTERN PYRENEES,FRANCE AND SPAIN. IV. ASCOMYCETES

Twenty species of lichenicolous ascomycetes are recorded for the western Pyrenees.Capronia hypotrachynaeEtayo & Diederich (onHypotrachynaspecies, also known from the Canary Islands and from Papua New Guinea),Llimoniella pubescensEtayo & Diederich (onLeprariaspecies, also from Scotland and Papua New Guinea),Polycoccum microcarpumDiederich & Etayo (onCladoniaspecies, also from Scotland),Skyttea megalosporaeEtayo & Diederich (onMegalospora tuberculosa),Sphaerellothecium cinerascensEtayo & Diederich (onCladonia parasitica) andS. parmeliaeDiederich & Etayo (onParmelias. str., also from Finland) are described as new.     

Two new species in the lichen genus Szczawinskia A. Funk

Szczawinskia leucopoda Holien & Tønsberg and S. foliicola Holien & Tønsberg are described from coastal Central Norway and Newfoundland, and from Papua New Guinea, respectively.     

Three new species of Oreophryne (Anura,Microhylidae) from Papua New Guinea

I describe three new species of the diverse microhylid frog genus Oreophryne from Papua New Guinea. Two of these occur in two isolated mountain ranges along the northern coast of Papua New Guinea; the third is from Rossel Island in the very southeasternmost part of the country. All three are the first Oreophryne known from these areas to have a cartilaginous connection between the procoracoid and scapula, a feature usually seen in species far to the west or from the central cordillera of New Guinea. Each of the new species also differs from the many other Papuan Oreophryne in a variety of other morphological, color-pattern, and call features. Advertisement-call data for Oreophryne species from the north-coast region suggest that they represent only two of the several call types seen in regions further south, consistent with the relatively recent derivation of these northern regions as accreted island-arc systems. The distinctively different, whinnying, call type of the new species from Rossel Island occurs among other Oreophryne from southeastern Papua New Guinea but has been unreported elsewhere, raising the possibility that it may characterize a clade endemic to that region.     

The feeding ecology of the African lily trotter Actophilornis africanus (Gmelin) at Lake Naivasha, Kenya

The only feeding habitats available to African lily trotters, Actophilornis africanus (Gmelin), at Lake Naivasha are mats of the alien water fern, Salvinia molesta Mitch. This has replaced the native floating leaved water lily beds. Lily trotters were able to use these mats, taking invertebrate food items from the surface or turning plants over and pecking at the rootlets. Pecking rates and turning rates responded to the nature of the available food, with pecking rates high and turning rates low when terrestrial arthropods were found on the mat surface. Both pecking rates and turning rates were low when large aquatic food items, such as the swamp worm (Alma emeni Michaelsen), were available. Pecking rates and turning rates were both high when the predominant food items were aquatic insect larvae. The largest of these (hydrophilid larvae) were taken in preference to the smaller but commoner chironomid larvae. Colonization of the mats of S. molesta by invertebrates was low if the mats were affected by wind action but higher if they were constrained by enclosure or stranding; mats with higher invertebrate densities supported more feeding lily trotters.     

Pathogenicity of Pratylenchus coffeae,Scutellonema bradys,Meloidogyne incognita,and Rotylenchus reniformis on Dioscorea rotundata

Low populations (200 specimens per plant) of Pratylenchus cofl''eae, Scutellonema bradys, Meloidogyne incognita, and Rotylenchulus reniformis stimulated the development of tops, roots, and tubers of Dioscorea rotundata "Guinea" yam. We demonstrated experimentally that P. coffeae was responsible for the deterioration in quality of the yam tuber in Puerto Rico, a condition known as a dry rot of yam. Initial populations of 600 P. coffeae, S. bradys, or M. incognita, and populations of 1,000 P. coffeae or S. bradys per plant were high enough to induce dry rot of the yam tubers. P. coffeae and S. bradys were pathogenic to yam cultivar Guinea, but M. incognita and R. reniformis did not cause necrosis or cracking of the tuber cortex in our experiments.     

A preliminary diagnosis and recommendation integrated system (DRIS) model for diagnosing the nutrient status of sweet potato (Ipomoea batatas)

Critical leaf nutrient concentrations have often been used to diagnose the nutritional causes of crop underperformance. Unfortunately, these diagnostic criteria are not available for mature, tuber-bearing sweet potato plants (the word ‘tuber’ being used to describe a swollen root rather than a swollen stem). The Diagnosis and Recommendation Integrated System (DRIS), however, provides a reliable means of linking leaf nutrient concentrations to the yield of sweet potato tubers, and may be developed for this crop using existing data from regional crop surveys. In the present study, tuber yield and leaf nutrient concentration data from a survey of sweet potato gardens conducted in the Papua New Guinea (PNG) highlands in 2005 were used to establish DRIS N, P, K, and S norms and statistical parameters for sweet potato. Although the database was relatively small, the norms derived for nutrient ratios of key biological significance, i.e. N/S and K/N, were within the expected narrow ranges for higher plants, giving credibility to both the database and the DRIS model. Data from future surveys and field trials may subsequently be used to enlarge the database allowing the refinement of model parameters and hopefully an expansion of diagnostic scope to include other macro and micro-nutrients. As it stands, though, this preliminary DRIS model for sweet potato is possibly the best diagnostic tool currently available for evaluating the N, P, K and S statuses of sweet potato crops in the pacific region.     

Root Hair Deformation, Bacterial Attachment, and Plant Growth in Wheat-Azospirillum Associations

Seven Azospirillum strains induced more deformation of root hairs of wheat than did strains of Rhizobium leguminosarum, Azotobacter chroococcum, or Escherichia coli. Azospirillum sp. strain Sp245 caused the most deformation. Strain Sp245 (isolated from surface sterile roots of wheat) and strain Sp7 (isolated from the rhizosphere of a forage grass) were compared with regard to their effects on root hair deformation, their attachment to roots, and their effects on the growth of four wheat cultivars. The amount of deformation caused by the two strains in the four cultivars increased in the following order: cv. Tobari, cv. Tonari, cv. BH1146, cv. Lagoa. Strain Sp245 attached to the roots of all cultivars in low numbers, and attachment did not increase with time (up to 48 h). Strain Sp7 attached in higher numbers, and attachment increased with time. Inoculation of the four cultivars of wheat had pronounced effects on root mass measured at maturity. The magnitude of the effects in the four cultivars increased in the following order: Tobari, Tonari, BH1146, Lagoa; these effects were progressively more positive for strain Sp245 and progressively more negative for strain Sp7. Concentrations of N in wheat did not vary substantially between cultivars or strains. Concentrations of K and P did not vary substantially between cultivars but did vary between strains, Sp245 effecting increases and Sp7 effecting decreases.     

Population genetic analyses of Plasmodium falciparum chloroquine receptor transporter gene haplotypes reveal the evolutionary history of chloroquine-resistant malaria in India

Inferring the origin and dispersal of the chloroquine-resistant (CQR) malaria parasite, Plasmodium falciparum, is of academic and public health importance. The Pfcrt gene of P. falciparum is widely known as the CQR gene and two major haplotypes of this gene (CVIET and SVMNT) occur widely across CQR-endemic regions of the globe. In India, studies to date of the Pfcrt gene have indicated the widespread prevalence of the SVMNT haplotype (prevalent in the South America and Papua New Guinea), whereas the CVIET haplotype, primarily found in southeast Asia, was not detected at a high frequency in India. This distribution pattern of the two most common CQR-Pfcrt haplotypes in India is quite surprising. Thus, in order to understand probable evolutionary and migration patterns of the CQR-Pfcrt haplotypes into India, we generated new sequence data of exon 2 of the Pfcrt gene and collected published information on the CQR-Pfcrt haplotype data from India, Papua New Guinea, southeast Asia and South America, and performed several population and evolutionary genetic analyses. Among several interesting findings, statistically significant longitudinal clines for the CVIET and SVMNT haplotypes (in opposite directions) in India, and the clustering of India and Papua New Guinea under the SVMNT-specific clade in the phylogenetic tree, are the two most remarkable aspects of the data. It also appears that both the SVMNT and CVIET haplotypes in India have migrated from southeast Asia. In particular, whereas the Indian CVIET haplotype has a southeast Asian origin, the SVMNT haplotype, prevalent in India, seems to have originated in Papua New Guinea and entered India through southeast Asia.     

Die küstenvegetation ostkanadas: D. Thannheiser. Münstersche Geographische Arbeiten. No. 10. Schöningh,Paderborn, 1981, 201 pp. 166 figs., 41 tables,DM. 41.50. ISBN 3-506-73210-2

Temperatures 10 and 2 cm above water level, in leaves of Salvinia molesta Mitchell, and 2 and 10 cm below water level, were measured in the field at hourly intervals over a total of 125 days. Temperature cycles of leaves and air had mean diurnal amplitudes of 8°C in summer and 17°C in winter; cycles in water lagged behind and had amplitudes which decreased with depth. Most parts of S. molesta were warmer than the air at a nearby weather station most of the time and there was temperature stratification in the water during the warm part of each day.Standard meteorological variables were selected, using stepwise regression, to predict daily maximum and minimum temperatures of S. molesta. Thermal inertia of water in the lake seemed to elevate S. molesta temperatures in autumn and depress them in spring compared with temperatures at the weather station. Better predictors were obtained by adding to meteorological variables a function based on the annual cycle of temperatures 10 cm below water level. Hourly temperatures experienced by S. molesta were predicted using curves fitted to diurnal cycles. The reliability of predictions was tested for each season of the year with independent data for a total of 78 days. Predicted temperatures were close to observed temperatures both in absolute terms and in terms of temperature-dependent growth rates of S. molesta.