Miracle-dz/UniFAR-FTUs huggingface dataset:
Infection of the single‐celled diatom Stephanodiscus alpinus by the chytrid Zygorhizidium: Parasite distribution within host population, changes in host cell size, and host–parasite size relationship

An epidemic caused by a Zygorhizidium species infecting the single‐celled planktonic centric diatom Stephanodiscus alpinus was analyzed for parasite distribution within the host population, final parasite size relative to host cell size, and size changes of infected and uninfected S. alpinus cells. Infections in the lake occurred at random within the whole host population. There was no evidence for aggregated or even distribution of the parasite individuals, indicating that the infections occur independently of each other. In enclosures in which light was enhanced compared to the lake, there tended to be an even parasite distribution within the host population, irrespective of whether plant nutrients were added. This suggests that infected host cells were negatively selected by the parasite zoospores under these conditions. Final parasite sporangium size and host cell size were positively correlated. Thus, parasite fecundity was limited by host cell size. Infected S. alpinus cells tended to be larger than uninfected cells, and the mean size of host cells within the population decreased during the epidemic. This might be due to selective infection of larger host cells or to the peculiar mode of cell division in diatoms.
Colour polymorphism in the intertidal snail Littorina rudis Maton

The tictors affecting the variation of shell colour morph frequencies of the intertidal snail Littorina rudis Maton have been examined using ordination and correlation techniques. The major gradient underlying variation in shell colour is related to habitat type and structure. Dark, patterned shells are characteristic of cliff and salt marsh habitats whilst light, unpatterned shells reach high frequencies on boulder shores. Colour morphs do not differ significantly in shell thickness and between-shore variation in colour morph frequencies cannot be directly attributed to habitat dilterences in the risk of shell injury, but to other factors associated with habitat type and structure, e.g. parasitism. It is suggested that the maintenance of shell colour polymorphism in L. rudis is probably mediated by selection on pleiotropic characters rather than shell colour alone.
Effects of Sowing Date and Insecticides on Cereal Aphid Populations and Barley Yellow Dwarf Virus on Barley in Kenya

The effects of the date of sowing and insecticide sprays on aphid populations and barley yellow dwarf virus (BYDV) incidence in barley was studied in Mau Narok, Kenya. Rhopalosiphum padi (L.) and Metopolophium dirhodum (WLK.) were common aphid species, but other cereal aphids present were Rhopalosiphum maidis (Fitch), Stiobion avenae (F.), Schizaphis grammum (Rond.) and Hysteroneura setaria Thom. The incidence of BYDV was significantly decreased in plots sown with seed that had been treated with imidacloprid (NTN-33893, Gaucho) and subsequently sprayed with foliar insecticide (Cypermethrin). Yield loss due to BYDV was also significantly different between the treatments and between the earlyplanted and the late-planted crop (P < 0.05). Grain yield and 1000-grain weight were not significantly different among insecticide treatments in the early-planted crop. In the late-planted crop, the yield increase with seed treatment alone was highly significant (P < 0.001), with a yield increase of 36-43%, more than that of the untreated control. Grain yield was significantly (P < 0.05) negatively correlated with the total number of cereal aphids. as well as with the numbers of R. padi alone. Zusammenfassung Einflus des Aussaattermins sowie von Insektiziden auf Getreideblattlauspopulationen und das Barley Yellow Dwarf Virus der Gerste in Kenia Untersucht warden die Einflusse des Aussaattermins sowie Insektizidbehandlungen auf die Blatttauspopulationen und das Auftreten des barley yellow dwarf Virus (BYDV) in der Gerste in Mau Narok, Kenia. Haufig traten die Blattlausarten Rhopalosiphum padi und Metopolophium dirhodum auf, andere Arten wie Rhopalosiphum maidis. Stiobion avenae, Schizaphis graminum und Hysteroneura setaria wurden auch gefunden. Das Vorkommen des BYDV wurde significant in den Versuchsparzellen reduziert, die mit Imidacloprid (NTN-33893. Gaucho) gebeizlem Saatgut ausgesat worden waren und anschliesend mit den Blattinsektizid Cyper-methrin behandelt wurden. Signifikante Unterschiede der Ertragsverluste durch BYDV wurden zwischen den unterschiedlichen Behandlungen und zwischen den fruher bzw. Spater ausgesaten Bestainden (P < 0.05) nachge-wiesen. Es gab keine signifikanten Unterschiede im Erlrag sowie 1000 Komgewicht zwischen den Insektizidbehandlungen bei den fruhausgesaten Bestanden. Bei den spater ausgesaten Beslanden konnte eine signifikant hohe Ertragssteigerung (P < 0.001). mit einer Ertragszunahme von 36-43%uber der Kontrolle. ermittelt werden. Der Kornerertragwar significant (P < 0.05) negativ korreliert mit der gesamten Blattlauszahl. sowie mit der Anzahl von R. padi allein.
Assessing the Water Quality of Two Creeks in Western Kentucky and Adjacent Tennessee using Biodegradable Dissolved Organic Carbon Analyses

ABSTRACT Assessment and comparison of the water quality of an agricultural creek (Ledbetter) and an undisturbed creek (Panther) emptying into Kentucky Lake, Kentucky and adjacent Tennessee, were conducted in July 2003 using biodegradable dissolved organic carbon (BDOC) analyses. Terrestrial, gravel bar, and surface water samples were collected in sterile whirl-pak bags from the creeks and analyzed for dissolved organic carbon (DOC) and biodegradable dissolved organic carbon (BDOC) content. Aliquots of samples were filtered and inoculated with creek microbes. Initial and final analyses were done using Oceanography-International Total Organic Carbon Analyzer with Infrared detector. The results show that the average BDOC concentration in Panther Creek (1.17 mg/liter; DOC = 2.50 mg/liter) was similar to that in Ledbetter Creek (0.87 mg/liter; DOC = 2.23 mg/liter). No clear DOC or BDOC trends were evident between the two creeks or well types sampled. Although results of the current study show no clear DOC or BDOC trends between the two creeks, it is important to monitor these creeks on a continual basis to maintain the quality of drinking water treatment and distribution systems.
Effect of neem seedling on infestation of Meloidogyne incognita in chickpea.

The present investigation was carried out to find the effect of planting neem seedlings alongwith chickpea in root-knot nematode (M.incognita) infested soil in two trials. It was found that the presence of neem seedlings inhibited the penetration of second stage juveniles of M. incognita in roots of chickpea and restricted the root-knot incidence as indicated by the reduced in roots in the first experiment and root-knot nematode galls in the second experiment in chickpea plants sown alongwith the neem seedlings.
Interferon‐γ plays a critical role in intestinal immunity against Salmonella typhimurium infection

Salmonella bacteria are a major cause of food‐borne infectious diarrhoea and there is great interest in understanding the pathogenesis of Salmonella infection and in vaccine development. Potential vaccines include the aromatic mutants of S. typhimurium. Such non‐lethal Aro mutants have also been useful for studying Salmonella infections in mouse models. Studies of systemic infection, using these Aro mutants, in both normal and cytokine gene knockout mice, indicate that interferon‐γ (IFN‐γ) plays a key role in the resolution of Salmonella infection. The present studies have investigated the outcome of oral infection in mice with attenuated Salmonella because this infection route mimics natural infection in humans. In IFN‐γ gene knockout (IFN‐γ–/–) mice, intestinal immunity was impaired and oral challenge resulted in disseminated septicaemia 2 weeks later. No dissemination of infection was seen in wild‐type mice. In wild‐type mice, both CD4 and CD8 cell numbers increased in the gut following Salmonella challenge, together with increased expression of major histocompatibility complex (MHC) II and vascular cell adhesion molecule‐1 (VCAM‐1). No such changes were seen in IFNγ–/– mice. Following oral challenge, antilipopolysaccharide (LPS) and antiphosphoryl choline antibodies increased by more than 100‐fold in both serum and faecal pellet extracts of IFNγ–/– mice compared with wild‐type mice. Our data show that IFN‐γ production is essential for resolution of enteric Salmonella infection and that antibody has little effect on this process.
Gas chromatograph analysis on closed nitrous oxide and air atmospheres of recalcitrant Quercus alba seeds

Storage of recalcitrant seeds remains an unsolved problem. The study of gaseous atmospheres could provide insights in understanding the metabolism of recalcitrant seeds and their potential in being used as means for storage. This study investigated the metabolism of the recalcitrant Quercus alba seeds when subjected under nitrous oxide (N2O) and air atmospheres. Seeds were placed in sealed atmospheric flasks of 98/2% N2O/O2. Three experiments were conducted to determine N2O uptake in relation to oxygen (O2) and carbon dioxide (CO2) levels. For the first experiment, “non-renewed” closed atmospheric systems with 98/2% N2O/O2 and air were used. Two more experiments were also conducted for the 98/2% N2O/O2 atmosphere to determine how rate of gas renewal (two and seven days) affects the N2O, O2, and CO2 gases quantitatively. Cumulative results on non-renewed flasks with 98/2% N2O/O2 showed that as time progressed, N2O uptake increased with variation in the magnitude of N2O utilization throughout the 37 experimental days, while seeds ceased O2 utilization by the 11th day. However, CO2 levels did not decrease, suggesting a shift toward fermentation processes. Finally, the two experiments for the 98/2% N2O/O2 indicated that the O2 levels did not deplete under a two-day gas renewal, suggesting a frequent gas renewal under low O2 storage conditions.
Ex Situ Plant Conservation: Supporting Species Survival in the Wild

x Situ Plant Conservation, edited by Edward O. Guerrant Jr., Kayri Havens, and Mike Maunder, is the first book to address integrated plant conservation strategies and to examine the scientific, technical, and strategic bases of the ex situ approach. The book examines where and how ex situ investment can best support in situ conservation. Ex Situ Plant Conservationoutlines the role, value, and limits of ex situ conservation as well as updating best management practices for the field, and is an invaluable resource for plant conservation practitioners at botanic gardens, zoos, and other conservation organizations; students and faculty in conservation biology and related fields; managers of protected areas and other public and private lands; and policymakers and members of the international community concerned with species conservation.
Variability of total soluble phenolic compounds and antioxidant activity in a collection of tetraploid wheat

The total soluble phenolic compounds (TSPC) and antioxidant activity (AA) of 113 tetraploid wheat samples including cultivars, landraces, and wild accessions of different Triticum turgidum subspecies, were assessed to point out potential sources for cereal-based functional foods. TSPC ranged from 1.28 to 3.15 mg g -1 as ferulic acid equivalents and AA, assessed by 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity test, ranged from 47.5% to 81.7%. Among cultivars of ssp. durum , the highest levels were observed in ‘Timilia’ and ‘Svevo’, while the ssp. dicoccoides showed the highest TSPC and AA among the accessions. The principal component analysis of data discriminated cultivars from wild accessions, and PC1 explained about 62% of variability. The TSPC were negatively correlated with thousand-kernel weight and grain yield per spike, while were positively correlated with AA, grain protein content, polyphenol oxidase activity, and brown index of whole meal and dough. The cultivar ‘Langdon’ coupled high TSPC and low brownness.
Effects of the Temperature Lowered in the Daytime and Night-time on Sugar Accumulation in Sugarcane

Abstract Sugarcane (Saccharum spp.) is a major crop grown for sucrose production. In Japan, its sucrose concentration is highest in winter. We examined the effects of the temperature lowered in the daytime and night-time (LDT and LNT, respectively) on sugar assimilation. Since photosynthetic and respiration rates change with temperature, we assumed that plants under LNT (LNT plants) would have low respiration rates and thus high sugar yields, whereas those under LDT (LDT plants) would have low rates of photosynthesis and thus low sugar yields. However, because of their acclimatisation to the reduced temperatures, LNT and LDT plants had sugar yields that were similar, or superior, to those of control plants. Sugar yield depends on biomass and sugar concentration; the stems of LNT and LDT plants did not grow as tall as those of the controls, but the sucrose concentrations in their stems were higher than in the controls. 13C analysis revealed no difference in the partitioning of photosynthates to the soluble sugar fraction between control plants and those treated with low temperature. Control plants had higher glucose concentrations in the stem than treated plants, in which new photosynthates appeared to be partitioned preferentially into sucrose. Low temperature enhanced the sucrose concentration in the sugarcane stem not by improving the carbon budget, but by promoting the partitioning of carbon to stored sucrose.
Forest resilience, tipping points and global change processes

Forests around the world are changing as a result of human activity. These changes have substantial impacts on the resilience of forests, possibly pushing them towards tipping points. The objective of this Special Feature is to present research that fosters the understanding of forest resilience and potential tipping points under global change. This editorial summarizes the key findings of the seven papers in this Special Feature and puts them in the wider context of resilience thinking. Synthesis. The contributions to this Special Feature show that resilience is a useful concept to understand ecosystem change but that we have to develop a better understanding of the mechanisms and feedback loops involved in forest resilience and potential tipping points. Finally, this Special Feature presents evidence about how resilience thinking is used to better understand and manage degraded forests.
Effects of Several Factors on Quantification of Fat, Protein, and Somatic Cells in Milk

Abstract Two studies were conducted to determine sources of variation in analysis of milk samples subjected to combinations of handling procedures typical of the Alabama DHIA testing program compared with those of a local milk processing plant. In study 1, cooled bulk tank samples from Jersey and Holstein herds were split and sent to five DHIA laboratories and one milk plant laboratory. All five DHIA laboratories reported similar results for fat with slight differences in percentage protein and SCC. Addition of preservative, shipping on ice, or method of shipping did not affect percentage fat. Milk plant electronic analysis was approximately . 05% higher than DHIA. Because the statistical difference is less than the accuracy of the Babcock test (± .1%), the practical significance of the difference is minimal. Samples without preservative or shipped on ice had a higher percentage of protein and lower SCC. Holding preserved samples up to 96 h did not affect electronic analysis of percentage fat but resulted in increased percentage protein. In study 2, samples held over the weekend by a commercial transport company had a similar percentage of fat but higher protein and SCC than in samples delivered directly.
Life History and Smolt-to-Adult Survival of Keogh River Steelhead Trout (Salmo gairdneri) and the Relationship to Smolt Size

A decade of data on wild steelhead trout (Salmo gairdneri) from a coastal stream in British Columbia demonstrated large fluctuations in smolt number, age structure, size, estimates of adult run sizes, smolt-to-adult survival, and adult age. Adult runs averaged 922 (range 209–2730) with approximately 10% repeat spawning incidence. Females repeat spawned more than males and were more abundant as kelts, but maiden run adults were equally male and female. The proportion of males returning after 1, 2, and 3 yr in the ocean averaged 3, 62, and 35%, respectively; 58 and 42% of females returned after 2 and 3 yr, respectively. Adult age structure, smolt number, and smolt size varied biennially. Adult size decreased with freshwater age, but increased with ocean age of returns. Males were larger at each ocean age. Mean number of smolts (50:50 sex ratio) was 5543 and varied fivefold. Mean smolt length was 173 mm and mean weight was 49 g. Smolts were 2–5 yr old, and freshwater age 3 was most prevalent (average 56%). M.
Role of the Cell Wall-Sustaining System in Gravity Resistance in Plants

Gravity resistance is one of two principal gravity responses in plants, comparable to gravitropism. In the final step of gravity resistance, plants increase the rigidity of their cell walls via modifications to the metabolism. Various constituents of the plasma membrane and the cytoskeleton play an important role in sustaining functions of the cell wall in gravity resistance. Mechanoreceptors located on the plasma membrane are involved in the perception of gravity signal. The perceived signal may be, at least partly, transformed and transduced via membrane sterol rafts, depending on its magnitude. Cellulose synthases and proton pumps are responsible for modifications to the cell wall metabolism and the apoplastic environment, respectively. On the other hand, the reorientation of cortical microtubules contributes to modification of growth anisotropy, which is related to gravity resistance. Also, microtubule-associated proteins are important in maintenance of the structure and induction of the reorientation of cortical microtubules. Gravity resistance in plants is thus mediated by the structural continuum or physiological continuity of cortical microtubules-plasma membrane-cell wall.
Towards a more exact definition of the importance of competition – a reply to Freckleton et al. (2009)

1. Freckleton, Watkinson & Rees (2009) criticize a recent paper by ourselves in this journal ( Brooker & Kikvidze 2008 ) as well as our earlier work on competition importance ( Brooker et al. 2005 ). In response, here we clarify our ideas with the aim of defining more clearly the key points of scientific debate, specifically (i) the definition of the importance of competition and (ii) its measurement.
The anatomy and development of the stem in the pteridophyta and gymnosperms

Comparatively little attention has been directed to the subject of the development of the stem. This research concerns itself chiefly with the development of the cauline fibro-vascular skeleton, since this appears to be most interesting from the phylogenetic and morphological standpoints. A study of numerous examples drawn from the main groups of the Pteridophyta and Gymnosperms has led to the conclusion that the polystelic type of Van Tieghem does not originate, as he states, by the repeated bifurcation of the epicotyledonary central cylinder but that the latter becomes at first a concentric fibro-vascular tube (Bündelrohr of De Bary), with gaps for the branches alone, or with gaps for both leaves and branches.
Agronomic and Seed Characteristics of Soybean with Reduced Raffinose and Stachyose

Monogastric animals cannot readily digest the raffinose and stachyose in soybean [Glycine max (L.) Merr. ], which reduces the amount of metabolizable energy that can be obtained from soybean meal. Soybean cultivars homozygous for the recessive allele stc1a from PI200508 have a reduced content of raffinose and stachyose and an increased content of sucrose. The objective of our study was to evaluate the influence of the stc1a allele on agronomic and seed traits. Two populations were developed by crossing two high-yielding cultivars to a donor with the stc1a stc1a genotype. Lines from each population with the stc1a stc1a genotype (stc1a lines) and Stc1a Stc1a genotype (Stc1a lines) were grown in replicated tests at three Iowa locations during 2002. There were no significant differences in the mean performance of stc1a and Stc1a lines in one or both of the populations for field emergence, seed yield, maturity, lodging, height, protein, oil, palmitate, stearate, oleate, linoleate, or linolenate. It should be possible to develop stc1a stc1a cultivars with reduced raffinose and stachyose that perform as well as conventional Stc1a Stc1a cultivars for all the agronomic and seed traits evaluated.
Chemical and structural effects of invasive plants on herbivore–parasitoid/predator interactions in native communities

The introduction and/or spread of exotic organisms into new habitats is considered a major threat to biodiversity. Invasive plants have been shown to negatively affect native communities, competing with and excluding other plants and disrupting a wide range of trophic interactions associated with them. In spite of this, thus far, few studies have explicitly studied the mechanisms underlying the displacement and potential local extinction of native herbivores and their natural enemies up to the third trophic level and even higher. Here, we formulate hypotheses on how structural and chemical characteristics of invasive plants may affect the plant‐finding abilities of herbivores and the host‐ or prey‐finding behavior of predators and parasitoids. The sudden incursion of an invasive plant into a native plant community may fragment native habitats and thus create structural barriers that impede dispersal and plant‐finding ability for herbivores and prey‐ or host‐finding ability for predators and parasitoids. At the same time, invasive plants may produce odors that are attractive to native insects and thus interfere with interactions on native plants. If invasive plants are both attractive and toxic to native insects, they may constitute ‘traps’ that are possibly beneficial against insect pests in agro‐ecosystems, but have conservation implications for native herbivores and their natural enemies. However, we also suggest that some herbivores, and by association their parasitoids, may benefit from the establishment and spread of exotic plants because they increase the amount of available resources for them to exploit.
The Evolution of Introns in Human Genes

Introns, which constitute the largest fraction of most eukaryotic genes and which had been considered to be neutral sequences, are increasingly acknowledged as functionally important parts of our genomes. For quite some time, research on levels of nucleotide substitution in human introns has been incomplete and yielded contradictory results, but the finishing of the chimpanzee genome allowed for new and more detailed studies that are proving to be key to unveil intronic functions. Keywords: introns; substitution rates; human–chimpanzee divergence; gene regulation