Miracle-dz/UniFAR-FTUs huggingface dataset:
Effects of soil compaction on plant growth phosphorus uptake and morphological characteristics of vesicular—arbuscular mycorrhizal colonization of Trifolium subterraneum

SUMMARY We investigated the effect of soil compaction and phosphorus (P) application on morphological characteristics of mycorrhizal colonization and growth responses, to determine the reasons for reduced responses observed in our previous work with compacted soil. Growth, phosphorus (P) uptake and intensity of vesicular–arbuscular (VA) mycorrhizal colonization were studied in clover plants (Trifolium subterraneum L.) with and without VA mycorrhizal colonization at two P applications and three levels of soil compaction. Phosphorus was supplied either at constant mass concentration (mg P kg−1 soil) or at constant volume concentration (mg P dm−3 soil). Increasing bulk density of the soil from 1·1 to 1.6 Mg m−3 significantly decreased root length and shoot d. wt, but increased the diameter of both main axes and first order lateral roots regardless of P application. Total P uptake and shoot d. wt of clover plants colonized by Glomus intraradices (Schenck & Smith) were significantly greater than those of non-mycorrhizal plants at all levels of soil compaction and both P applications. However, soil compaction to a bulk density of 1.6 Mg m−3 (penetrometer resistance = 3.5 MPa at a matric potential of − 33 kPa) significantly decreased mycorrhizal growth response. There was no evidence that the increased volume concentration of P at high bulk densities was responsible for the reduced responses. Soil compaction had no significant effect on the fraction of root length containing arbuscules and vesicles, but total root length colonized by arbuscules, vesicles or by any combination of arbuscules, vesicles and intra-radical hyphae significantly decreased as soil compaction was increased. The air-filled porosity of highly compacted soil, which varied from 0.07 to 0.11 over the range of matric potentials encountered (− 33 and − 100 kPa), had no significant effect on the intensity of internal colonization.
Ecological Predictors of African Wild Dog Ranging Patterns in Northern Botswana

Extinction risk in African wild dogs (Lycaon pictus) has been linked to their wide-ranging movement behavior. However, drivers of variability in African wild dog ranging are not well understood. This study examines the effects of intrinsic and extrinsic factors on ranging patterns and describes scale-dependent and intra-annual variation in the ranging of 5 packs of African wild dogs in the Okavango Delta from 2007 to 2010. 95% fixed kernel home ranges ( = 739 ± 81 km2) and daily step lengths ( = 8.5 ± 0.5 km) in this study are larger than have generally been reported for African wild dogs elsewhere. Little seasonal variation in daily ranging distances was observed despite home-range contractions during denning to 27% of packs' ranges outside the denning period. During nondenning periods, litter size was the most influential driver of ranging patterns, with large litters associated with reduced pack movements and smaller home ranges at all temporal scales. Pack size was also a significant driver of home-range size (but not daily distance travelled) at weekly timescales, where larger packs utilized smaller ranges. Daily temperatures were inversely related to home-range size and step length at short timescales, while higher flood levels were related to reduced ranging distances at intermediate timescales. Our results indicate that extrinsic drivers of African wild dog ranging behavior tend to be scale dependent, while intrinsic factors may be more influential for ranging patterns than previously reported.
LACTATE METABOLISM IN RAINBOW TROUT

We have investigated the metabolic fate of blood lactate in resting rainbow trout and in fish recovering from a bout of exhaustive exercise. At rest and during recovery from exercise, the majority of blood lactate was oxidized, the proportion increasing with increasing oxygen consumption. It is estimated that, during recovery from exhaustive exercise, lactate released from the muscle has the potential to fuel a significant portion of oxidative metabolism. The bulk of the remaining blood lactate reappeared in the muscle lactate pool, probably via direct uptake by the muscle. There was a significant incorporation of blood lactate into the muscle glycogen pool, providing strong evidence for in situ glycogenesis as the mode for muscle glycogen replenishment. To investigate the role of the liver in blood lactate clearance, trout were functionally hepatectomized by ligation of the hepatic portal circulation. The exercise performance of hepatectomized fish was equal to that of sham- operated fish and controls, indicating that muscle relies primarily on endogenous fuel stores. Furthermore, blood lactate levels immediately after exercise were greater and muscle metabolic recovery was faster in hepatectomized fish than in sham-operated fish and controls. These observations suggest that glycogen resynthesis in trout muscle may be retarded because of a non- recoverable loss of substrate (i.e. lactate) from the muscle, because the lactate released is utilized by the liver. These results are discussed in view of what is known about these processes in other ectothermic vertebrates.
Reductions in insecticide use from adoption of Bt cotton in South Africa: impacts on economic performance and toxic load to the environment

The study reported presents the findings relating to commercial growing of genetically-modified Bt cotton in South Africa by a large sample of smallholder farmers over three seasons (1998/99, 1999/2000, 2000/01) following adoption. The analysis presents constructs and compares groupwise differences for key variables in Bt v. non-Bt technology and uses regressions to further analyse the production and profit impacts of Bt adoption. Analysis of the distribution of benefits between farmers due to the technology is also presented. In parallel with these socio-economic measures, the toxic loads being presented to the environment following the introduction of Bt cotton are monitored in terms of insecticide active ingredient (ai) and the Biocide Index. The latter adjusts ai to allow for differing persistence and toxicity of insecticides. Results show substantial and significant financial benefits to smallholder cotton growers of adopting Bt cotton over three seasons in terms of increased yields, lower insecticide spray costs and higher gross margins. This includes one particularly wet, poor growing season. In addition, those with the smaller holdings appeared to benefit proportionately more from the technology (in terms of higher gross margins) than those with larger holdings. Analysis using the Gini-coefficient suggests that the Bt technology has helped to reduce inequality amongst smallholder cotton growers in Makhathini compared to what may have been the position if they had grown conventional cotton. However, while Bt growers applied lower amounts of insecticide and had lower Biocide Indices (per ha) than growers of non-Bt cotton, some of this advantage was due to a reduction in non-bollworm insecticide. Indeed, the Biocide Index for all farmers in the population actually increased with the introduction of Bt cotton. The results indicate the complexity of such studies on the socio-economic and environmental impacts of GM varieties in the developing world.
Distillation Time Changes Oregano Essential Oil Yields and Composition but Not the Antioxidant or Antimicrobial Activities

Oregano (Origanum vulgare L.) is an important medicinal, culinary, and essential oil plant. Oregano essential oil is extracted from either leaves or shoots through steam distillation. Researchers and industry in various countries reported different distillation times (DTs) for oregano; however, there are no reports on optimum DT. This study evaluated the effect of DT (1.25, 2.5, 5, 10, 20, 40, 80, 160, 240, 360 min) on essential oil yield, composition,andantioxidantactivityoftheoreganoessentialoil.Ingeneral,theconcentration ofthelowboilingessentialoilconstituents(alpha-thujene,alpha-pinene,camphene,l-octen-3- ol, myrcene, alpha-terpinene, paracymene, beta-phellandrene/limonene, gamma-terpinene, cis-sabinene hydrate, terpinolene) were high est at the shortest DT (1.25 or 2.5 min), reduced with increasingDT up to40min,and then stayed thesame.However,theconcentration ofthe major oil constituent, carvacrol, was lowest at the shortest DT of 1.25 min (18%) and increased steadily with increasing DT up to 40 min, where itleveled at 80% to 82%. The concentration of other higher boiling constituents (borneol, 4-terpineol, beta-bisabolene, beta-caryophylenne) was maximum at 5 to 20 min DT. Maximum yield of the low boiling constituents was achievedatrelativelyshortDT,at '20minDT,andpeakedagainat240minDT.Maximum yields of alpha-terpinene,beta-phellandrene/limonene,and gamma-terpinene were reached at 240 min DT. Maximum yields of paracymene cis-sabinene hydrate, terpinolene, and transsabinene hydrate were also achieved at 240 min DT, but yields at 20 min DT were not different. Yields of borneol, 4-terpinenol, carvacrol, beta-caryophyllene, and beta-bisabolene also were highest at 240 min DT. Distillation time at 20, 80, or 360 min did not alter antioxidant or antimicrobial activity of oregano oil. The relationship between the con- centration and yield of the constituents with DT was adequately modeled by the asymptotic and Michaelis-Menten nonlinear regression models, respectively. Results demonstrated that 1) DT can be used to obtain oregano essential oil with differential composition; 2) maximum essential oil yield of steam-distilled oregano leaves could be obtained at 240 min DT; and 3) reports on oregano essential oil yield and composition using different DTs may not be comparable. Results from this study will aid in comparing published reports on oregano essential oil that used different lengths of DT.
Microfibril angle of cell wall in Eucalyptus wood : implication on breeding programs

The great challenge of forest breeders for the future is to provide genetic varieties (genotypes) well adapted to several industry needs such as energy, p ulp and paper and solid wood. In this context, researches a re needs to generate a better understanding about variabilit y, correlations and genetic and environmental control of some wood properties. Genetic studies and selection process requires the development of high throughput phenotyping tools. In this study we are interested on the orientation of the cellulose microfibrils in the S 2 layer of cell wall in Eucalyptus wood and its implications on others timber properties. The use of new methods and tools and genetic approaches can make a significant contribution to understand how and why microfibril angle changes in Eucalyptus wood.
A stochastic model for shelter use in a mobile fish population: the effect of intraspecific competition

Understanding the functional significance of shelter for a mobile fish population requires knowledge of the behavioural mechanisms that govern the dynamics of shelter use. We used Bullhead (Cottus gobio) as a model system to investigate the effect of intraspecific competition on shelter use. A series of field experiments were conducted in which shelter availability and population density were controlled. For each experiment the location of each individual fish was observed over a period of 10 days. We then constructed a continuoustime Markov-chain model for the movement of fish between shelters and the open stream, which explicitly parameterised exploitation competition and interference competition for shelter, and which accounted for two different size classes of fish. Analysis of the model showed strong evidence of exploitation competition, which was highly dependent on size, and strong evidence of interference competition, which limited the ability of unsheltered fish to colonise vacant shelters at high population densities. Different formulations of the interference competition were compared using the AIC information criterion. The formulation that best fitted the observations modeled interference competition as an increasing function of average shelter occupancy, rather than using the population density per se.
Evaluation of antagonistic activity in vitro of endophytic fungi associated with camu-camu (Myrciaria dubia) / Avaliação da atividade antagonista in vitro de fungos endofíticos associados ao camu-camu (Myrciaria dubia)

Endophytic fungi are those that inhabit the inner tissue of their hosts, playing varied and narrow ecological relations without showing visible symptoms. It is estimated that the majority of plant species have not yet been sorted endophytic microorganisms and little-known properties, but some potentially suitable for biotechnological applications. Camu-camu (Myrciaria dubia) has great economic potential, the nutritional characteristics of the fruit, such as high production of vitamin C. Were isolated and cultured 307 endophytic fungi associated with the leaves and stems of M. dubia in order to verify the antagonistic activity, for the production of diffusible and volatile substances against the following pathogens: M. fructicola, Colletotrichum gloeosporioides and Aspergillus parasiticus. It was found that 22 isolates inhibited the growth of at least one target plant pathogens, showing inhibition potential (IP) from 25.62% to 93.84%, five endophytic stood with inhibition percentage above 50%, by producing diffusible and volatile substances. The competitive interactions were analyzed according to Badalyan scale, and there was a higher frequency among the fungi, the interaction type A ("deadlock" with mycelial contact). It is concluded that endophytic fungi isolated from leaves and stems of M. dubia, have promising biotechnological potential in biocontrol of plant pathogens (A.parasiticus, M. fructicola and C. gloeosporioides).
Numeric analysis of planktonic spatial patterns revealed by echograms

Observations of acoustic images made along a transect perpendicular to the Coast, off Villefranche-sur-Mer, allow one to recognize the hydrological zone corresponding to a surface density gradient characterizing the Ligurian Sea front (Mediterranean Sea). Combinations of statistical and geometrical parameters from the digitized echoes enable discrimination between different classes of patches in relation to the frontal structure during one transect recorded on December 20, 1990. Patch recognition is based on the extraction of the general trend of each column and each row of the digitized data matrix by Eigenvector filtering. Multivariate analysis (principal component analysis and discriminant analysis) run on a 650 patches × 19 variables matrix shows a high negative relation between statistic and geometric parameters of the patches. The two main discriminant parameters are shape and echo strength of patches. From the convergence of our results in the Ligurian front with those of previous works made in other frontal region, it is suggested that this method could be generalized for quantifying and standardizing studies of the patchiness of plankton.
Revegetating weed-infested rangeland with niche-differentiated desirable species

Abstract The goal of this study was to determine the potential to revegetate weed-infested rangeland by maximizing niche occupation and resource capture by desirable species. We hypothesized that as desirable species richness increases, weed establishment and growth decrease, provided that the desirable species differ in niche. Three desirable species with differing spatial and temporal growth patterns, [Agropyron cristatum (L.) Gaertn. , var. Hycrest (crested wheatgrass), Elytrigia intermedia (Host) Nevski, var. Rush (intermediate wheatgrass), and Medicago sativa L. , var. Arrow (alfalfa)], and 1 weed [Centaurea maculosa Lam. (spotted knapweed)], were grown in a multiple replacement series. All species were sown simultaneously in spring 1996, simulating revegetation of a site containing spotted knapweed seeds in the seed bank because of prior infestation. Desirable species richness varied among plots, while the total number of desirable seeds sown per plot was held constant. Although the desirable species were shown to differ in niche, desirable species richness or mixture did not affect soil water depletion or spotted knapweed recruitment in 1996 or 1997. These results suggest that revegetation of weed-infested rangeland must also include active control of weeds emerging from the soil seed bank. Only then can other strategies, such as maximizing niche occupation by desirable species, be expected to provide long-term success.
Which Statistic?/O. Zeller Robertson Jr., Saginaw Valley State College

are trying to get away from subjects that require a heavy investment of time in learning mathematics. In any event, my experience in teaching political science statistics and methodology courses has been that a number of students are either not interested in the subject or have great difficulty with it. These students take the course only because it is required. Some instructors feel that microcomputers can be used in several ways to lessen the fear students have of statistics. One way is to let
VARIATION IN PHYSIOLOGICAL AND CHEMICAL CHARACTERISTICS AT DEVELOPMENTAL STAGE IN DIFFERENT DISEASE-RESISTANT VARIETIES OF CAMELLIA OLEIFERA

Camellia oleifera Abel. is an important edible oil tree species from Southern China. Anthracnose, caused by Colletotrichum gloeosporioides (Penz.), is responsible for more than 50% of C. oleifera production loss, and C. oleifera varieties differ in their resistance to anthracnose. The aim of this study was to assess resistance mechanisms by monitoring physiological and biochemical parameters of differentially resistant cultivars during the development of C. oleifera. C. oleifera fruit coats were analyzed between May and September for tannins, anthocyanins, soluble sugar content, pH, buffer capacity, activity of three enzyme s(Phenylalanine ammonia lyase; polyphenol oxidase; peroxidase) and free radical scavenging capacity. Anthocyanins, soluble contents and free radical scavenging capacity were related to anthracnose resistance, with anthocyanins and soluble sugar contents of the resistant varieties nearly twofold higher than those of susceptible varieties. The results of free radical scavenging capacity showed that extracts from highly resistant varieties of C. oleifera fruit coats performed more efficiently in the scavenging of free radicals than those from susceptible varieties. The three enzyme activities of highly resistant varieties rose rapidly and continuously, while those of medium resistant and highly susceptible varieties increased initially and then decreased. Tannins, pH and buffer capacity showed no significant differences between different cultivars. This study broadens the understanding of disease resistance mechanisms in C. oleifera.
HEAVY METAL LEVELS OF MULBERRY (MORUS ALBA L.) GROWN AT DIFFERENT DISTANCES FROM THE ROADSIDES

The heavy metals pollution of mulberry cultivated soil, mulberry leaf and fruit, growing at different distances from the roadside were investigated in the Upper Coruh Valley of Turkey. The rate of heavy metals in soil, leaf and fruit were detected by Inductively Coupled Plasma Optical Emission Spectrophotometer (ICP-OES). All of the heavy metals (Zn, Mn, Cu, Co, Cr, Pb, Cd and Ni) were found in soil and parts of plant and their highest level at a distance of 20 m from the roadside. At a distance of 20 m from the roadside, the soil was found to be contaminated by Zn (330.7 mg kg -1 ), Cu (217.5 mg kg -1 ), Pb (500.2 mg kg -1 ) and Cd (4.24 mg kg -1 ) pollutants. The concentration of Pb in mulberry fruit was found to be more than the permissible limits at a 20 and 100 m distances from the roadside with its 0.467 and 0.419 mg kg -1 values, respectively. At all of distances, the concentration of Ni in fruit was found higher than the permissible limits. The results reflected a strong relationship between soil and fruits for contamination with some heavy metals.
A Checklist of the Weed Flora of Qassim Region, Saudi Arabia

An inventory survey of agricultural farms was conducted to document the weed flora of Qassim region, Saudi Arabia. A total number of 105 weed species belonging to 78 genera and 25 Angiospermic families were recorded. Plant specimens were collected from 22 different sites and in each site 2-3 agricultural forms, representing various ecological habitats in winter and summer were investigated. Poaceae (21 %) was found to be the most dominant family in the area, followed by Asteraceae (13 %) and Brassicaceae (12%). The study revealed the presence of five succulent and two parasitic species within the weed flora of the region. The most common weed species in the region are Cynodon dactylon (L.) Per. , Malva parviflora L. , and Portulaca oleracea L.
A Multiyear, Large-Scale Comparison of Arthropod Populations on Commercially Managed Bt and Non-Bt Cotton Fields

Abstract Field studies were conducted in 2000–2002 to compare foliage-dwelling arthropod populations on Bacillus thuringiensis Berliner (Bt) (Bollgard) cotton and non-Bt (conventional) cotton season-long in South Carolina, Georgia, northern Alabama, and southern Alabama. For each of these four regions, three or four paired fields were sampled weekly in each of the 3 yr. Each pair of fields consisted of a Bt and a non-Bt cotton field, both at least 5 ha in size. The dominant arthropod taxa collected included target pests (heliothine moths and Spodoptera spp.), nontarget pests (stink bugs and plant bugs), and generalist natural enemies [Geocoris spp. , Orius spp. , Solenopsis invicta (Buren), ladybeetles, and spiders]. Where target pests were present, particularly Helicoverpa zea (Boddie), their numbers were consistently significantly lower in the Bt cotton fields. Natural enemy populations generally were not significantly different between the Bt and the non-Bt cotton fields (50% of all comparisons) and, where significant differences were present, natural enemy abundance usually was higher in the Bt than the non-Bt cotton fields. These differences were correlated with lower insecticide use on the Bt than the non-Bt cotton fields, particularly in South Carolina, where target pest pressure was heaviest. When presented with insect eggs or larvae as prey items, the larger natural enemy populations in Bt cotton fields exhibited significantly higher predation rates. These results show that Bt cotton has no significant adverse impacts on the nontarget arthropod populations studied and, compared with insecticide-treated non-Bt cotton, Bt cotton supports higher natural enemy populations with significant positive impacts on biological control.
Physiological Aspects of Desiccation Tolerance

INTRODUCTION . 195 ALGAE 197 LICHENS . 199 FUNGI . 204 BRYOPHYTES, PTERIDOPHYTES, AND SPERMATOPHYTES 205 RNA and Protein Synthesis 206 Mosses •. • 206 Seeds 208 Des��cation. oj Germinating . Se�ds and Seedlings 211 'Presowmg drought hardenmg 212 Photosynthesis, Respiration, and Dark Fixation oj CO} 2 1 3 Bryophytes 2 1 3 Vegetative tissues o f vascular plants 2 1 7 Seeds 218 Ultrastructure, Permeability, and Membranes, and the Possible Bases of Desiccation Tolerance 220