Climate,land-use and Prosopis ferox recruitment in the Quebrada de Humahuaca,Jujuy, Argentina

Prosopis ferox grows in upper-elevation, inter-montane valleys between 2600 and 3800 m in Northwestern Argentina and Southern Bolivia. Throughout its range, P. ferox has largely been used as local fuel, building material and food for livestock. In order to evaluate the causes of the recent increase in P. ferox density and range distribution, we compare tree recruitment of P. ferox at 15 stands in the Quebrada de Humahuaca, Jujuy, Argentina, with the environmental and socioeconomic changes in the past 150–200 years. Based on tree recruitment, a general pattern of greater establishment from the mid-1970s to 1990 was identified. This regional pattern is consistent with precipitation variations during the 20th century showing abundant rainfall in the 1970s and 1980s. In addition, historical records indicate that the density of domestic grazers decreased dramatically in the second half of the 20th century. The reduction of browsing by livestock might have also favored the P. ferox recruitment over this interval. However, during the 1990s reduced establishment has occurred at a time of low stock densities suggesting significant precipitation is necessary for the expansion and establishment of these forests. Simply reducing stocking levels will not lead to the long-term recovery of these forests.     

Cytokinins of the Developing Mango Fruit : Isolation, Identification, and Changes in Levels during Maturation

The cytokinin activity has been isolated and identified from extracts of immature mango (Mangifera indica L.) seeds. The structures of zeatin, zeatin riboside, and N⁶-(Δ²-isopentenyl)adenine riboside were confirmed on the basis of their chromatographic behavior and mass spectra of trimethylsilyl derivatives. Both trans and cis isomers of zeatin and zeatin riboside were also identified by the retention times of high performance liquid chromatography. In addition, an unidentified compound appeared to be a cytokinin glucoside.

The concentration of cytokinins in the panicle and pulp of mango reached a maximum 5 to 10 days after full bloom and decreased rapidly thereafter. The cytokinin level in the seed remained high until the 28th day after full bloom. The quantity of cytokinins in pulp per fruit increased from the 10th day after full bloom, the maximum being attained around the 50th day after full bloom. Similarly, the amount of cytokinins per seed increased from the 10th day after full bloom, reaching a peak on the 40th day and decreasing gradually thereafter.

A high percentage of fruit set in mango was persistently maintained by supplying 6-benzylaminopurine (1.5 × 10³ micromolar) onto the panicle at the anthesis stage and by supplying gibberellic acid (7.2 × 10² micromolar) and naphthalene acetamide (3.1 × 10 micromolar) at the young fruit stage.

     

The geographic ranges of Martes species (Carnivora,Mustelidae) in the Middle Urals in the Late Pleistocene and Holocene

Martes mandibles from Late Pleistocene and Holocene sites in the Middle Urals were identified to the species level using discriminant analysis. As has been shown, sable lived there in the Late Pleistocene, with its geographic range covering all this area until the end of the 18th century; however, its range started to reduce towards the north and northeast in the early 19th century. Over 150 years, the southwestern boundary of the sable range shifted by 3° to reach the current position by the mid-20th century. The pine marten appeared in the Middle Urals in the Holocene no later than 8000 years ago and inhabits this territory at present.     

Growth of the prothoracic H-organ in larvae of Galleria

The volume of the recently discovered neurohaemal H-organ has been measured during the penultimate (6th) and the last (7th) instar of Galleria mellonella. It has been found that the volume of H-organ increases from 1 nl at the beginning of 6th instar to 2.21 nl at the beginning of 7th instar. The maximum volume of 3.32 nl has been reached at day 6 of the 7th instar. According to the microvolumetric measurements, the H-organ is approx 3-times smaller than a single prothoracic gland. In contrast to the prothoracic glands, which exhibit a cyclic growth pattern in the 6th instar, the H-organ and the interganglionic connectives show a more-or-less regular, acyclic type of growth. No special volumetric changes in the H-organ have been noticed at the time of ecdysteroid peaks in the whole body, but the possible involvement of the H-organ in the transport of ecdysteroids is discussed.     

A Pathogenic Bacterium,Enterococcus faecalis,to the Beet Armyworm,Spodoptera exigua

A bacterial disease was found in the beet armyworm, Spodoptera exigua (Hübner). Blackened body of the infected larvae was a typical symptom of the epizootic disease especially at the intersegmental areas. We isolated the bacteria from the hemolymph of the infected 5th instar larvae and identified the isolate as a gram-positive bacterium, Enterococcus faecalis. When the 4th instar larvae were injected with the bacteria, half lethal dose of the bacteria was estimated as 22,593 colony-forming units (cfu) per larva and half lethal time of the bacteria was estimated as 2 days at 10⁷ cfu injection and 6 days at 10⁸ cfu injection. The bacteria were strongly resistant to each 1,000 ppm of ampicillin, kanamycin, and streptomycin. They were, however, relatively susceptible to mixture (1,000 ppm) of different combinations of the three antibiotics.     

High pH,ammonia toxicity,and the search for life on the Jovian planets

The Jovian planets have environments apparently suitable for the evolution of life, but, nevertheless, present severe challenges to organisms. One such challenge arises from the presence of ammonia. Ammonia is an efficient biocide, its effect being dependent on pH as well as on concentration. The effects of pH and ammonia concentration were studied separately, where possible, on a variety of organisms, including some isolated from natural environments of high pH and/or ammonia concentration. Escherichia coli andBacillus subtilis are both extremely sensitive to ammonia. An aerobic organism (growth up to pH 11.4) from an alkaline spring is more resistant, but exhibits a toxic response to ammonia at a pH much lower than its maximum for growth. The greatest ammonia resistance has been found in an unidentified organism growing at near neutral pH. Even in this case, however, survival at ammonia concentrations reasonably expected on the Jovian planets is measured in hours. This is, nevertheless, two to three orders of magnitude longer than forE. coli. Our data support the tentative conclusion that contamination of the Jovian planets with terrestrial organisms that can grow is unlikely. However, the range of toxic response noted, coupled with the observation that terrestrial life has not been exposed to high ammonia concentrations for millions of years, suggests that adaptation to greater ammonia tolerance may be possible.     

Above- and belowground dynamics of plant community succession following abandonment of farmland on the Loess Plateau, China

Aboveground and belowground changes during vegetation restoration and vegetation successions need to be characterized in relation to their individual responses to changes in soil resources. We examined above- and belowground vegetation characteristics, soil moisture, and nutrient status at the end of the growing season in 2006 in plots with vegetation succession ages of 2, 4, 6, and 8 years (two replicates each) that had been established on abandoned cropland, where potatoes had been grown for 3 years, using hoe and plow cultivation, immediately prior to vegetation clearance and subsequent natural plant colonization. A plant community comprising pioneer species [e.g., Artemisia capillaries, (subshrub)] was characterized by low levels of species richness (7.5?±?1.4 species m^?2), plant density (35.7?±?4.2 stems m^?2), fine root length density (940.1?±?90.1 m m^?2), and root area density (2.3?±?0.3 m² m^?2) that increased rapidly with time. Aboveground and belowground characteristics of both A. capillaries and the later successional species, Stipa bungeana (C3 perennial grass), increased in the first 6 years, but in the following 2 years A. capillaries declined while S. bungeana thrived. Thus, the fine root length density of A. capillaries, 812.4 m m^?2 after 2 years, changed by a factor of 1.7, 2.0, and 0.4 in the 4th, 6th, and 8th years, whereas that of S. bungeana changed from 278.4 m m^?2, after 4 years, and by 1.7 and 23.3 times in the 6th and 8th years, respectively. Secondary vegetation succession resulted in reduced soil moisture contents. Soil available P and N mainly influenced aboveground characteristics, while soil moisture mainly influenced belowground characteristics. However, soil moisture had no significant affect on S. bungeana belowground characteristics at the population level in this semiarid region.     

Yellow wagtail Motacilla flava Linnaeus, 1758 (Passeriformes, Motacillidae, Motacillinae), in the Middle Volga Region: Geographical distribution, nesting biotopes, and numbers

A critical assessment of the literature data on the yellow wagtail Motacilla flava Linnaeus, 1758 (Passeriformes, Motacillidae, Motacillinae), at the turn of the 19th–20th centuries is carried out, assessment of its current numbers is given, and limiting factors and patterns of the species distribution on the study area of the European part of Russia, including the Middle Volga Region, are identified.     

Mycotoxins and usnic acid and their distribution in lichens belonging to the genera Cetraria,Flavocetraria, and Cladonia

The content and the pattern of distribution of mycotoxins and usnic acid in thalli of lichens belonging to the genera Cladonia (four species), Cetraria (two species), and Flavocetraria (two species) have been studied using the method of immunoenzymatic analysis. Statistically significant differences have been estimated between the upper and the lower parts of the thalli. The levels of the mycotoxins in the lower, older parts of the thalli have been higher than in the upper, younger ones. The comparison of lichen specimens belonging to the same species and collected in the same location at different years did not reveal statistically significant differences in the content of mycotoxins both in the upper and the lower parts of the thalli. Statistically significant differences in the usnic acid content have been revealed only in the case of C. stellaris. In the upper part of the podetia of this species, the usnic acid content has been higher than in the lower one.     

ent-Eudesmane sesquiterpenoids, galloyl esters of the oak lactone precursor, and a 3-O-methylellagic acid glycoside from the wood of Platycarya strobilacea

ent-Eudesmane sesquiterpenoids, 8,11-dihydroxy-2,4-cycloeudesmane, 11-hydroxy-2,4-cycloeudesman-8-one and 2,4-cyclo-7(11)-eudesmen-8-one, were isolated from the wood of Platycarya strobilacea, which has been used as an aromatic tree since at least the 18th century. On charring the wood, 2,4-cyclo-7(11)-eudesmen-8-one was detected in the smoke. In the charred wood, the concentrations of ellagitannins, such as galloyl pedunculagin, dramatically decreased, whereas concentrations of pentagalloyl glucose, and other gallotannins were relatively stable. In addition, two other compounds, the 6′-O-m- and p-digalloyl oak lactone precursor and the 3-O-methylellagic acid 4′-O-(4″-O-galloyl)-xylopyranoside, were isolated from the charred wood along with m- and p-digallic acid.     

Habitat use of the Rio Grande silvery minnow (Hybognathus amarus) during a long-term flood pulse in the Middle Rio Grande, New Mexico

The Middle Rio Grande (MRG) of New Mexico has been influenced by man for over 500?years. Native Americans began diverting water to irrigate agricultural crops in the floodplain in the 14th century. The Spanish followed and increased agricultural irrigation to over 125 000 acres. Frequent flooding of the MRG valley in the 19th century led to many engineering projects in the early 20th century to control flooding. A series of impoundment dams, diversion dams, and levees were constructed. The loss of floodplain habitats throughout the MRG Valley has altered the riparian community and caused the demise of many fish species. A controlled flood pulse from Cochiti Reservoir, New Mexico was initiated in April 2005 to support the recovery of the endangered Rio Grande silvery minnow, Hybognathus amarus. This study documents habitat selection by larval fishes in a restored floodplain in the Rio Grande, NM. Larval fish light traps captured 394 larvae representing four cyprinid species (Pimephales promelas, H. amarus, Cyprinella lutrensis and Cyprinus carpio). Results for CCA indicate that Hybognathus amarus prefer shallow, low velocity habitats. Results from Chao-Jaccard similarity index indicated that relative contribution was highest in P. promelas at 64% followed by H. amarus 33%. Results from (dis)similarity analysis reveal that species composition between habitat orientation and date was highest in H. amarus at 42% followed by P. promelas 40%. Cyprinella lutrensis and C. carpio represented 9.5 and 8.5%, respectively. A general linear model indicated that only depth and velocity were significantly different (p?=?0.02 and p?=?0.03 respectively).     

Endocrine manipulations,juvenile hormone and ontogenesis of male sexual behaviour in locusts

By injection of azadirachtin (AZA) to 5th instar hoppers of Locusta migratoria migratorioides, “over-aged” nymphs were produced, some of which survived for long periods without moulting to adults. Such over-aged male nymphs exhibited mating behaviour belatedly, though at a lower intensity than normal adults. Juvenile hormone (JH) markedly intensifies male sexual behaviour in crowded adult (6th instar) Locusta; thus, the lower intensity of sexual behaviour of the over-aged nymphs might have been caused by a low endogenous JH titre, or by a weaker response to the hormone. To clarify this point, chemically allatectomized over-aged 5th instar nymphs were produced by combined treatment with precocene and AZA. These exhibited a very low intensity of mating behaviour. Injections of exogenous JH III intensified the mating behaviour of the chemically allatectomized over-aged 5th instar male nymphs in a dose-dependent way, but the effect was weaker than in chemically allatectomized adult males. AZA-induced over-aged 4th instar male Locusta hoppers also exhibited mating behaviour. By injection of AZA, 5th instar over-aged hoppers of Schistocerca gregaria were also produced. Males showed mating behaviour belatedly, despite the fact that JH completely controls male sexual behaviour in this species. The intensity of this behaviour was again lower than in adults. Interrelations between integumental morphogenesis, “ethogenesis” of male sexual behaviour, and endocrine factors in locusts are discussed.     

Characterization and the developmental role of plasma juvenile hormone esterase in the adult cabbage looper,Trichoplusia ni

Juvenile hormone (JH) esterase was characterized from the plasma of adult females of the cabbage looper, Trichoplusia ni, and compared with that present in 4th and 5th instar larvae. Ester hydrolysis was the principal route of JH metabolism. Gel filtration of plasma resolved a single peak of JH esterase which was distinct from that of the α-naphthyl acetate (α-NA) esterase activity. The JH esterase apparent molecular weight was 62,000 in prepupae and virgin, female adults and 69,000 in 2-day-old 4th instar larvae. Broad range isoelectric focusing of plasma of prepupae and adults resolved a major peak of activity at pH 5.5 with a minor peak of activity at pH 6.1 and in 4th instar larvae at pH 5.45 and 5.8, respectively. By this method JH esterase was resolved from the α-NA esterase activity. The plasma of prepupae and adults metabolized JH I at about twice the rate of JH III. JH esterase activity from adult plasma was more stable than the α-NA esterase activity. Adult JH esterase activity was insensitive to inhibition by O,O-diisopropyl phosphorofluoridate in contrast to that of the α-NA esterase activity. Mated females oviposited 8 times more eggs than virgin females to 10 days after emergence. The total haemolymph protein content of virgin females remained high throughout the period of study whereas mated females showed a significant decline beginning on day 4. JH esterase activity remained unchanged in virgins whereas it declined drastically in mated females. The α-NA esterase activity declined to low levels shortly after emergence in both groups. JH and α-NA esterase activity was not affected by the application of the juvenoid, (RS)-methoprene. The present study provides evidence of a functional role for JH esterase in JH metabolism and reproduction in adult T. ni. JH esterases in the adult were identical to that of prepupae by the methods described above.     

Middle Jurassic (upper Bajocian) marine vetigastropods from the Western Saharan Atlas,Algeria

Whereas Middle Jurassic gastropods are very well known in Europe and other regions of the world, these faunas have been much less studied from northern Africa and most contributions available in literature have been based on relatively well-preserved material. Except a little lower Bajocian fauna from the Central High Atlas (Morocco) described at the turn of the 21th century, nothing is known about the Middle Jurassic gastropods of the southwestern Tethyan margin. The present paper aims to update the systematics of two vetigastropod species: Obornella cf. granulata (Sowerby, 1818) and Ambercyclus ornatus (Sowerby, 1819) recently found in the upper Bajocian succession of the Ksour Mountains (Tniet el Klakh Formation) at western Saharan Atlas (northern Algeria). The new Ambercyclus material found in well-preserved conditions confirms the absence of umbilicus in Ambercyclus; thus, we emend the original generic diagnosis. The specimens of Obornella cf. granulata and Ambercyclus ornatus represent the first occurrence of both genera and species in the upper Bajocian marine deposits of the western Saharan Atlas, and provide new taxonomic and palaeobiogeographic information about Middle Jurassic vetigastropods in Algeria.     

Life Cycle of the Mulberry Longicorn Beetle,Apriona germari Hope on an Artificial Diet

Mulberry longicorn beetle, Apriona germari, was reared on an artificial diet to investigate its life cycle. Average egg period was 17.95 days. Most larvae pupated at the 8th (33.3%) or 9th (33.3%) instars, but others emerged from the 7th to the 11th instars. The total duration of larval stage from the 1st to the end of the 9th and the 11th instars were 176.2 and 251.5 days, respectively. For terminatiopn of diapause and acceleration of pupation, low temperature treatment at 5°C for 60 days was highly effective. Average pupal period for female and male was 19.3 and 18.4 days, respectively. Average longevity of adults was similar with 40.5 days for female and 44.3 days for male. Mating had occurred from about 10 days after the adult emergence, and then a female adult laid one or two eggs per day. Average number of eggs oviposited by a female was approximately 47.7. Total life span of A. germari, when reared on an artificial diet in the laboratory, ranged broadly from 197.5 days to 331.5 days mainly depending on the larval period.     

Relation of feeding,growth, and metabolism to age in the larval,female house cricket

The maximum growth rate occurs in the first half of the 7th and 8th larval instars of the house cricket, at which time food and water consumption is maximal. Growth ceases in the last 2 to 3 days of each instar when food consumption is almost nil. The metabolic rate is twice, and the locomotory activity is four times, higher in the first 2 to 3 days than in the last 2 to 3 days of each instar. The %-gain in dry wt is 120% for the 7th and 139% for the 8th instar. The average digestive coefficient (AD) for the 8th instar is 67% and the average efficiency of food conversion to tissue (dry wt ECI) is 27%. The average daily food consumption for 8th instar larvae is 31.4 mg, and, therefore, we calculate that an average of 12 mg food is burnt per day for energy which is confirmed by the observed average V_O2 of 1.2 ml O₂/g-cricket/hr. Total lipids as %-total wt (239% mg-gain) increases in the first 4 days then remains constant in spite of cessation of feeding in the last 2 days. The RQ confirms the conversion of carbohydrates to lipids in the first half of each instar. In the moulting cycle carbohydrates are used for maintenance (when not feeding), but lipids are used at apolysis.     

Distribution of the hordatines in barley

Concentrations of agmatine, coumarylagmatine and the antifungal hordatines in the shoots of barley seedlings have been determined at various stages of growth. Coumarylagmatine declined with age on a fresh weight basis, both in diurnal illumination and in continuous darkness. Hordatines A and B (estimated together) declined in the light to the 30th day after germination but their concentrations were stable in the dark to the 12th day. Hordatine M declined in the light to the 30th day and in the dark to the 12th day from germination. Agmatine declined in both light and dark to the 12th day. On the 30th day from germination potassium deficiency caused an increase in hordatines A + B ( × 6), hordatine M ( × 2) and agmatine ( × 13). Infection of the 11-day-old seedlings with mildew (Erysiphe graminis) caused an increase in the content of hordatine A + B ( × 6), hordatine M ( × 2) and agmatine ( × 2) 13 days later. Hordatines occurred in seedlings of H. bulbosum, H. distichon, H. murinum and H. spontaneum, though not in seedlings of H. jubatum, maize, millet, oats, rice, rye or wheat. Arginine decarboxylase activity declined with age in barley seedlings grown in the light or dark from the 3rd to the 12th day.     

Selection and evaluation of RT-qPCR reference genes for expression analysis in the tiny egg parasitoid wasp,Trichogramma dendrolimi matsumura (Hymenoptera: Trichogrammatidae)

The egg parasitoid, Trichogramma spp., is an important biological control agent used against a broad range of Lepidopteran pests in agriculture and forestry. The biology of Trichogramma has been studied in details. Further studies should focus on the molecular mechanisms of Trichogramma by qualifying the expression of related genes It is critical to select appropriate reference genes for normalizing RT-qPCR results and establishing a robust method for quantifying target gene expression. This study aimed to identify and validate appropriate reference genes for use in RT-qPCR analysis of Trichogramma dendrolimi. Ten candidate housekeeping genes, namely beta-actin (ACTIN), forkhead box O (FOXO), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), heat shock protein 90 (HSP90), ribosomal protein L10a (RPL10a), L18 (RPL18), L28 (RPL28), S13 (RPS13), S15 (RPS15), and superoxide dismutase (SOD), were tested for their suitability as reference genes for developmental stage (3rd, 4th, 5th, 6th, 7th, 8th, 9th, and 10th day after parasitization), tissue (head, thorax, and abdomen of adults), sex of adults (male and female), and temperature (17℃, 25℃, and 32℃). According to the GeNorm analysis, a robust analysis should involve using an appropriate combination of reference genes, namely, at least three genes for different development stages, two genes for different tissues, two genes for different sex, and two genes for different temperatures, respectively. According to the RelFinder method by the integrated results of GeNorm, NormFinder, BestKeeper, and the ΔCt method, we identified the developmental stage-specific reference genes SOD, GAPDH, and ACTIN; tissue-specific reference genes RPL18 and RPS15; sex-specific reference genes RPL18 and SOD; and temperature-specific reference genes RPL18 and RPL10a. This study provides a standardized procedure for the quantification of gene expression in T. dendrolimi and will be helpful for future biological control programs using Trichogramma wasps.     

The production and storage of Nerve Growth Factor in vivo by tissues of the mouse,rat, guinea pig,hamster, and gerbil

The Nerve Growth Factor (NGF) content in vivo of tissues from the mouse and rat at various stages of development from 3 days embryonic gestation to the attainment of full maturity has been determined using the standard biological assay. A less extensive survey has also been made of tissues from the guinea pig, hamster, and gerbil. With the exception of the well-documented high levels of NGF in the mouse submaxillary glands, none of the organs examined contained detectable NGF. These results, which are consistent with those previously reported using the biological assay, stand in contrast to the high levels of NGF detected in virtually all tissues by some published radioimmunoassays. It is likely that the discrepancies are due to the use in the radioimmunoassays of antisera containing antibodies to proteins other than NGF, and to the inability of one-site radioimmunoassays to distinguish between the presence of NGF and that of agents capable of binding NGF. The apparent lack of widespread NGF production in vivo contrasts with the ability of many tissues to synthesize the protein in vitro. This may imply that physiologically significant levels of NGF are below the limits of sensitivity of the assay systems presently available, that NGF synthesis in vivo occurs only during a very restricted period of development, or that the presence of a normal innervation pattern influences NGF production.