Plant Biology

Sex determination is an important developmental event in the life cycle of all sexually reproducing plants. Recent studies of sex determination in many plant species, from ferns to maize, have been fruitful in identifying the diversity of genetic and epigenetic factors that are involved in determining the sex of the flower or individual. In those species amenable to genetic analysis, significant progress has been made toward identifying mutations that affect sex expression. By studying the interactions among these genes, pictures of how sex-determining signals are perceived to activate or repress male-or female-specific genes are emerging.

Fluoride (F) as one of the most toxic pollutants affecting the environment severely restricted plant growth and development. The Fluoride toxicity was studied in young olive plants (Olea europaea L. cv Chemlali), which were irrigated for 5 months with increasing NaF concentration: 0 (control), 20, 40, and 80 mM NaF. The NaF application resulted in an increase of the F content in plant tissues with a higher level in roots compared to leaves. Olive plants treated with 20 or 40 mM NaF maintained their mineral status and activated their antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase). In fact, lipid peroxidation and electrolyte leakage were not affected in the plant leaves. However, olive plants treated with 80 mM NaF showed (i) the highest reduction of antioxidant enzyme activities and mineral contents, and (ii) an increase of oxidative stress markers such as hydrogen peroxide, thiobarbituric acid reactive substances and electrolyte leakage in both roots and leaves.

Epidemiology of powdery mildew on cucurbits were studied in Rohilkhand region of Uttar Pradesh, India. Most of the cucurbits were found infected in one or the other localities of the study area which comprised eight districts of Rohilkhand region of Uttar Pradesh. The study area showed the occurrence of and . The knowledge regarding perpetuation of the pathogens and annual recurrence of the disease on cucurbits seems to remain evading in the near future.

Oithona spp. standing stock and production is considered relatively stable in space and time as a result of continuous breeding, low metabolism, reduced predation mortality and the ability of these small cyclopoids to exploit microbial food webs more efficiently than larger copepods. However, through a review of the published literature, we show that Oithona spp. biomass can vary widely both over the year and with latitude. Thus, the present study set out to investigate the basin scale variability in biomass, stage structure and reproduction of Oithona spp. in relation to changes in hydrographic, physico-chemical and biological parameters encountered during three cruises conducted between April and November 2002 in the Irminger Sea, North Atlantic. Here we found that Oithona spp. biomass varied significantly with temperature and with dinoflagellates biomass concentration. On the other hand, Oithona similis egg production rates increased with both ciliates and dinoflagellates concentrations, rather than with temperature. The inverse relationship we found between Oithona spp. naupliar recruitment with Calanus spp. and fish larvae abundance suggests that predation pressure may contribute to control the spatial variation in the stage structure and biomass of Oithona spp. and that the nauplii of this genus may serve as a food source for other planktonic organisms prior to the spring phytoplankton bloom.

We compare the long-term and seasonal patterns of abundance and phenology of the cyclopoid copepod Oithona similis at the L4 site (1988 -2013) in the North Atlantic and at the LTER-MC site (1984 -2013) in the Mediterranean Sea to investigate whether high temperature limits the occurrence of this species with latitudinal cline. The two sites are well suited to testing this hypothesis as they are characterized by similar chlorophyll a concentration (Chl a) but different temperature [sea surface temperature (SST)]. The abundance of O. similis at L4 was 10 times higher than at LTER-MC. Moreover, this species had several peaks of abundance during the year at L4 but a single peak in spring at LTER-MC. The main mode of temporal variability in abundance was seasonal at both sites. The abundance of O. similis was negatively correlated with SST only at LTER-MC, whereas it was positively correlated with Chl a at both sites. Oithona similis had a temperature optimum between 15 and 208C reaching maximum abundance at 16.58C at LTER-MC, but showed no Chl a optimum at either site. We conclude that the abundance of O. similis increases with prey availability up to 16.58C and that temperature .208C represents the main limiting factor for population persistence.

The present investigation reviews published data on the feeding rates and prey selection of Oithona similis females, Calanus finmarchicus nauplii and females in the Irminger Sea in April/May and July/August 2002. Our aim was to examine how the feeding rates and prey selection of these three copepod stages respond to concomitant changes in microplankton community composition and prey abundance. Copepods typically ingested prey overall according to its ambient concentration although significant species and stage-specific differences in prey-type ingestion and selection were apparent. Despite being of comparable weight, the ingestion rates of C. finmarchicus nauplii were always higher than those of the O. similis females. Moreover, C. finmarchicus nauplii and O. similis females fed preferentially on diatoms and ciliates respectively, whereas adult female C. finmarchicus showed limited prey selectivity. Copepod grazing impact on total and on ciliates/ dinoflagellates standing stock was ,0.5 and ,2%, respectively. We attribute this result to a combination of low grazing rates, low copepod abundance and low microplankton biomass, all of which are indicative of the non-bloom conditions under which these experiments were conducted. The differences in copepod feeding rates and prey selection we report reflect species and stagespecific eco-physiological adaptations, which may act as important driving forces for marine ecosystem structuring and functioning.

The pelagic copepods Oithona similis and Calanus helgolandicus have overlapping geographic ranges, yet contrast in feeding mode, reproductive strategy and body size. We investigate how these contrasting traits influence the seasonality of copepod abundance and reproductive output under environmental variation, using time series data collected over 25 years at the Western Channel Observatory station, L4. The proportional change in egg production rate (EPR, eggs female -1 d -1 ) over the annual cycle was ~10-fold and similar for both species, although EPR of O. similis was only ~11% that of C. helgolandicus. The timing of EPR maxima for O. similis coincided with increased sea surface temperature (SST) in summer, likely due to a temperature-dependent brooding period. Conversely, EPR of broadcast spawning C. helgolandicus was more strongly related to net heat flux and diatom biomass, both parameters associated with the spring phytoplankton bloom. In both species, female body mass correlated negatively with SST, with a 7.5% reduction in body mass per °C in C. helgolandicus compared to just 2.3% in O. similis. Finally, seasonality of EPR and adult and copepodite abundance was strongly decoupled in both species, suggesting that optimum conditions for reproduction and abundance occurred at different times of the year.

We report here the effect of replacing one or both of the purine or pyrimidine blocks of a diblock stilbene donor-acceptor capped hairpin with locked nucleic acid (LNA) bases on the dynamics and efficiency of hole transport. The structures of the DNA and LNA:DNA hybrids are tentatively assigned to B-or A-type structures on the basis of their circular dichroism spectra. Replacing the bases in either the A-block or the G-block of the diblock DNA hairpin with LNA bases results in a modest decrease in the base-to-base hopping rate constant and quantum yield for charge separation. Somewhat larger decreases are observed when all of the purine or pyrimidine bases are replaced by LNA bases.

Switchgrass (Panicum virgatum L.) is a perennial C4 grass with the potential to become a major bioenergy crop. To help realize this potential, a set of RNA-based resources were developed. Expressed sequence tags (ESTs) were generated from two tetraploid switchgrass genotypes, Alamo AP13 and Summer VS16. Over 11.5 million high-quality ESTs were generated with 454 sequencing technology, and an additional 169 079 Sanger sequences were obtained from the 5′ and 3′ ends of 93 312 clones from normalized, full-length-enriched cDNA libraries. AP13 and VS16 ESTs were assembled into 77 854 and 30 524 unique transcripts (unitranscripts), respectively, using the NEWBLER and PAVE programs. Published Sanger-ESTs (544 225) from Alamo, Kanlow, and 15 other cultivars were integrated with the AP13 and VS16 assemblies to create a universal switchgrass gene index (PviUT1.2) with 128 058 unitranscripts, which were annotated for function. An Affymetrix cDNA microarray chip (Pvi_cDNAa520831) containing 122 973 probe sets was designed from PviUT1.2 sequences, and used to develop a Gene Expression Atlas for switchgrass (PviGEA). The PviGEA contains quantitative transcript data for all major organ systems of switchgrass throughout development. We developed a web server that enables flexible, multifaceted analyses of PviGEA transcript data. The PviGEA was used to identify representatives of all known genes in the phenylpropanoid-monolignol biosynthesis pathway.

The aim of this study was to determine the effects of the inoculation of maize seeds with mixtures of bacteria (Azotobacter chroococum, Azotobacter vinelandi, Bacillus megaterium, Bacillus licheniformis) during different phenophases (6-7 leaves, silking and wax ripeness stage) and on the nitrogen dynamics, total number of microorganisms, number of azotobacter and aminoheterotrophs in Chernozem and grain yield of maize hybrid ZP 684 during 2006, 2007 and 2008. Nitrogen amount in soil was significantly higher in 2006, due to favourable meteorological conditions for microbial activity (higher total number of microorganisms and number of azotobacter), than in 2007 and 2008. The minimum amount of nitrogen was in the stage of wax ripeness although the total number of microorganisms, azotobacter and aminoheterotrophs were the largest. Seed inoculation of maize significantly increases the values of all studied parameters

The yield and weediness of ZP 684Ultra maize hybrid under application of cycloxydim, alone or in combination with some postemergence herbicides for broad-leaf weed control, were evaluated. Maize tolerance to cycloxydim is achieved by the introduction of CTM allele into a single cross hybrid, for the maximal herbicide dose proposed by producer to be used in practice. The application of herbicides included nine treatments: cycloxydim+mesotrione, cycloxydim+tembotrione, only cycloxydim, all at different rates, and untreated control. Grain yield was significantly higher in all treatments than in the control, and also in 2010 than in 2011. The most effective against weeds and yield productive were combinations of cycloxydim and tembotrione.

The objective of this study was to determine the changes in weed infestation of maize caused by crop sequence. The trial encompassed two types of the crop sequence: maize-soybean-wheat-maize (CS I) and maize-wheat-soybean-maize (CS II). The number of weed species as well as weed fresh biomass decreased, in the CS I, while the number of plants per weed species increased. On the other hand, in the CS II, the number of weed species and the number of plants per weed species increased, while weed fresh biomass insignificantly decreased. Crop sequencing in the crop sequence I (CS I) contributed, to greater extent, to the reduction of maize weed infestation than in the crop sequence II (CS II).

Weed control in sunflower is a necessary practice in cropping, because the weed infestation level directly affects the intensity of competitive relationships between crops and weeds. Suppression of some annual and invasive weeds is difficult due to deficiency of an effective herbicides and the lack of the effects of applied herbicides in years with dry springs, such was in 2009. The two-year study dealt with observed effects of applied herbicides on weeds in different stages of sunflower growth. The intensity of weed infestation of sunflower, expressed through the number of weed species, number of plants per weed species and weeds fresh biomass, was always lower on the treated area and different at particular crop developmental stages. This affects the sunflower plant height, which was higher on the average in variants with the herbicide applications (70.4 cm) than in variants without the herbicides application (69.5 cm). Weed control in sunflower crops has to carry out with adequat...

24-epibrassinolide (24-EBL) is plant steroid hormone that can regulate several physiological effects in plants, including promotion of cell growth and induction of heat stress tolerance. The purpose of this work is to investigate the influence of various concentrations of 24-EBL on the dehydration mechanism of seedlings of two maize hybrids (ZP434 and ZP704). Control and treated samples were subjected to isothermal conditions for dehydration processes. The effects of carbohydrates and mineral contents on the possible changes in the dehydration mechanism (from kinetics standpoint) were investigated. Comparing control samples to samples treated with 24-EBL, it was found that different dehydration mechanisms exist. The differences arise from the influence of 24-EBL, that causes a significant increase of phosphorus values for ZP704, whilst the reverse was identified for ZP434. It was assumed that the plumule sensitivity to dehydration stress originates from the interaction of water with primary amino groups as cations in polyamines, for lower concentrations of 24-EBL. It was found that the temperature variation (105-130 °C) leads to situations where trehalose does not arrive fast enough to "replace the water", because its handicap to binds (by hydrogen bonds) to biomolecules instead of water. It was found that 24-EBL cause changes of carbohydrates properties, which are important for the defense mechanism from environmental stresses.

The two herbicides and their combined treatment influenced the change of water input in each of 15 investigated maize inbreds. The water volume (ml) fluctuated between 11 to 110% in shoot and 23 to 275% in root, what introduced the change of free energy (G) from -254.6 to -151.6 KJ in shoot and from -248.0 to -172.3 KJ in root. The difference in free, potential energy between non-and treatment (oΔtreatG) was in shoot from 11.1 to 90.2 KJ and in root from 16.8 to 75.7 KJ. Further, the lower magnitude of oΔtreatG amplitude between root and shoot implicated the tolerance of genotypes to applied herbicides. The energy, spent in biosynthesis of 1mg dry substance was amounted from 75.6 to 16.8 KJ mg-1; the applied herbicide treatments assembled the group of genotypes with lowered necessity of this energy, what has the positive implications in the sense of thermodynamics.

We aimed to evaluate a computer-aided diagnosis (CADx) system for lung nodule classification focussing on (i) usefulness of the conventional CADx system (hand-crafted imaging feature + machine learning algorithm), (ii) comparison between support vector machine (SVM) and gradient tree boosting (XGBoost) as machine learning algorithms, and (iii) effectiveness of parameter optimization using Bayesian optimization and random search. Data on 99 lung nodules (62 lung cancers and 37 benign lung nodules) were included from public databases of CT images. A variant of the local binary pattern was used for calculating a feature vector. SVM or XGBoost was trained using the feature vector and its corresponding label. Tree Parzen Estimator (TPE) was used as Bayesian optimization for parameters of SVM and XGBoost. Random search was done for comparison with TPE. Leave-one-out cross-validation was used for optimizing and evaluating the performance of our CADx system. Performance was evaluated using area under the curve (AUC) of receiver operating characteristic analysis. AUC was calculated 10 times, and its average was obtained. The best averaged AUC of SVM and XGBoost was 0.850 and 0.896, respectively; both were obtained using TPE. XGBoost was generally superior to SVM. Optimal parameters for achieving high AUC were obtained with fewer numbers of trials when using TPE, compared with random search. Bayesian optimization of SVM and XGBoost parameters was more efficient than random search. Based on observer study, AUC values of two board-certified radiologists were 0.898 and 0.822. The results show that diagnostic accuracy of our CADx system was comparable to that of radiologists with respect to classifying lung nodules.

The phylogenetic relationships of Pyricularia species and species from related genera were established from sequences of the internal transcribed spacer ribosomal RNA gene. Phylogenetic analysis disclosed a consistent correlation with spore morphology. Most Pyricularia species studied, and two species of Dactylaria that have obpyriform conidia, fell within the Magnaporthaceae cluster with high bootstrap support. Pyricularia variabilis was more related to Dactylaria, Tumularia or Ochroconis species than to the Magnaporthaceae. Dactylaria and species of Nakataea, Ochroconis, Pyriculariopsis and Tumularia were distinct from the Magnaporthaceae, and the genus Dactylaria is polyphyletic. The combination of morphological and molecular characters, such as spore morphology and ITS ribosomal DNA sequences data, suggested that conidial shape could be a primary character to distinguish Pyricularia from related genera.

Moelleriella pumatensis, a fungal pathogen infecting scale insect nymphs (Hemiptera), is described and illustrated as a new species from Pu Mat National Park in Vietnam. This species is unique in producing a golden yellow spore mass surrounding the stroma. In surveys throughout the year in Vietnam, only the anamorphic state has been found in the natural forest. Morphological characters and phylogenetic analysis of translation elongation factor 1-α (tef1) reveals this species as an anamorph of Moelleriella.

Atherosclerosis is a build-up of low-density lipoproteins (LDL) in the channels of blood vessels. This occludes the vessels and, occurring in the carotid arteries, portends conditions that favour stroke. This work is an attempt to mathematically represent the physiological process of atherosclerosis caused by plaques on the walls of the human arteries. Provide insight into the effect of blood flow velocity on wall shear stress and its implications on atherosclerosis progression in a human carotid artery via computational simulation. The effect of blood velocity on plaque growth and progression is simulated using COMSOL multi-physics. The human carotid was modeled in 2-D with Stokes law for model flow. The simulation began with a plaque-free vessel with velocities of 30 m/s -125 m/s. Results showed that the rate of plaque initiation dropped as the blood velocity increased from 30 m/s to 125 m/s; higher inlet velocities gave lower plaque growth; the highest degree of 30% stenosis was recorded at a blood velocity of 30 m/s. Plaque height significantly

Wood is traditionally modeled as an orthotropic material, with direction dependent transport properties, in this way homogenizing the specific structure of wood: a cellular material with growth rings, consisting of early wood and late wood layers. In this paper we present a mesoscopic model for vapor transport in wood, where earlywood and latewood are modeled as distinct materials. The sorption and vapor transport properties for early-and latewood are determined using a unit cell model with constant cell geometry. These properties are used in two-dimensional calculations of vapor transport in a piece of wood consisting of several growth rings. The mesoscopic results are compared to measurement results and to macroscopic results using homogenized orthotropic transport properties. For vapor transport in radial and tangential direction the difference between meso-and macro modeling of wood is negligible, justifying the vapor transport modeling with homogenized orthotropic transport properties.

Sporotrichosis is a fungal infection of subcutaneous or chronic evolution, inflammatory lesions characterized by their pyogranulomatous aspect, caused by the dimorphic fungus Sporothrix schenckii. Adenosine deaminase (ADA) is a ''key'' enzyme in the purine metabolism, promoting the deamination of adenosine, an important anti-inflammatory molecule. The increase in ADA activity has been demonstrated in several inflammatory conditions; however, there are no data in the literature associated with this fungal infection. The objective of this study was to evaluate the activity of serum ADA (S-ADA) and lymphocytes (L-ADA) of rats infected with S. schenckii. We used seventy-eight rats divided into two groups. In the first experiment, rats were infected subcutaneously and in the second experiment, infected intraperitoneally. Blood samples for hematologic evaluation and activities of S-ADA and L-ADA were performed at days 15, 30, and 40 postinfection (PI) to assess disease progression. In the second experiment, it was observed an acute decrease in activity of S-ADA and L-ADA (P \ 0.05), suggesting a compensatory mechanism in an attempt to protect the host from excessive tissue damage. With chronicity of disease the rats in the first and second experiment at 30 days PI showed an increased activity of L-ADA (P \ 0.05), promoting an inflammatory response in an attempt to combat the spread of the agent. Thus, it is suggested that infection with S. schenckii alters the activities of S-ADA in experimentally infected rats, demonstrating the involvement of this enzyme in the pathogenesis of sporotrichosis.

The current investigation was performed with the objective of finding the scientific reason for health benefit of Occimum sanctum, Phyllanthus niruri and Cadaba fruticosa, simultaneously evaluating the antioxidant activity of ethanol, methanol and aqueous extracts. The potent antioxidant, antimicrobial and anti-inflammatory leaf extracts can be used for producing a novel ointment formulation, functional food or neutraceutical, in combination. The qualitative analysis of antioxidant activity was performed by reducing power assay and DPPH assay and in vitro anti-inflammatory test was performed by the HRBC membrane stabilization method. Further, the bioactive compounds present in the alcoholic leaf extracts were detected by GC-MS analysis and their applications were noted. Comparative studies on antimicrobial and anti-inflammatory activity of the 3 samples were determined using respective standards. Cadaba fruticosa is an under-emphasized herb, whose potential in the medical world is yet to be explored in details. Hence, Cadaba fruticosa has been chosen as one of the herbal plants for comparative study with Ocimum sp. and Phyllanthus sp. Ethanolic extract of showed significant antimicrobial activity against the tested bacterial strains. Methanolic extract of Ocimum sanctum at 200 μg mLG 1 depicted highest scavenging activity, 81.1%. The results also indicate that Cadaba fruticosa possesses significant free radical scavenging and anti-inflammatory activities in vitro. GC-MS analysis of the herbs revealed the presence of several bioactive compounds.

The use of agro-industrial by-products such as biofertilizers hinders polluting discharges and allows savings commercial fertilizers. The application of vinasse (a by-product of ethanol manufacture) in sugarcane (Saccharum officinarum) production was evaluated in two soils of Uruguay (L1 and LB2). In a first ratoon crop, 150 and 300 m3 ha-1 of vinasse were applied (V150 and V300) and compared with the application of fertilizer (F) and a Control (C) with no application. Then, production and the plant’s N, P, K, Ca and Mg contents were determined. Vinasse and fertilizer applications increased sugarcane growth, as compared to C. However, there were no differences between vinasse dosses. The L1 fertilization treatment produced higher stem yield than vinasse application, whereas LB2 caused no differences. The application of vinasse at LB2 and L1 increased K uptake, exceeding the control, by 151 and 133 kg ha-1 of K, respectively, indicating that it could substitute fertilizer, while supp...

The boiled leaves of Artemisia campestris (Asteraceae) was used as a folk-medicine against ophidian and scorpion envenoming in rural and nomad populations, but its bona fide mechanisms are still unknown. In this report, the effect of the aqueous dry leaves' extract of this plant on hemodynamic variations induced by Buthus occitanus tunetanus venom was assayed in pregnant and non pregnant rats. Our results showed that the venom induced hypertension magnitude was much important in pregnant rats (maximal of 156% of baseline) than in cycling ones (maximal of 143.9% of baseline). When injected alone, the aqueous leaves extract of A. campestris induced a progressive significant diminishing of the mean arterial pressure both in 72.4 ± 7.6% and out of pregnancy (90.4 ± 4.4%). This effect did completely abolish the venom induced hypertensive shock, when envenomed rats were pretreated with the extract. It was concluded that aqueous extract of A. campestris leaves prevents the induced hypertensive phase induced by the scorpion venom, probably through adrenergic pathway. The potential of A. campestris water-boiled extract to revert hypertension is sought to be useful for antihypertensive drugs development; and worth much merit to be investigated.

The use of agro-industrial by-products such as biofertilizers hinders polluting discharges and allows savings commercial fertilizers. The application of vinasse (a by-product of ethanol manufacture) in sugarcane (Saccharum officinarum) production was evaluated in two soils of Uruguay (L1 and LB2). In a first ratoon crop, 150 and 300 m 3 ha -1 of vinasse were applied (V150 and V300) and compared with the application of fertilizer (F) and a Control (C) with no application. Then, production and the plant's N, P, K, Ca and Mg contents were determined. Vinasse and fertilizer applications increased sugarcane growth, as compared to C. However, there were no differences between vinasse dosses. The L1 fertilization treatment produced higher stem yield than vinasse application, whereas LB2 caused no differences. The application of vinasse at LB2 and L1 increased K uptake, exceeding the control, by 151 and 133 kg ha -1 of K, respectively, indicating that it could substitute fertilizer, while supplemental nitrogen fertilization would be required for maximum yield. The low use-efficiency of potassium (K) in vinasse treatments suggests that there was excessive consumption. Although vinasse increased soil exchangeable K, its residual effect would be insufficient for the second ratoon harvest, requiring annual applications.

Fusarium wilt is the most destructive fungal disease in flax, limiting flax cultivation in all the main flax and linseed growing countries. The causative agent is seedborne and soilborne fungus F. oxysporum f. sp. lini. Here, we report, for the first time, genome assemblies of five highly pathogenic isolates of Fusarium oxysporum f. sp. lini, namely monoisolate 39 and strains F329, F324, F282, F287. In addition, syntenic analysis provided a powerful approach to distinguish between core and lineage-specific parts of the genome. These results lay a solid foundation for comparative genomics studies of plant fungal pathogens, evolution of pathogenicity, and virulence factors underlying the dynamics of host-pathogen interactions, thus eventually offering solutions to Fusarium disease control.

Black rot of cruciferous plants, caused by Xanthomonas campestris pv. campestris, causes severe losses in agriculture around the world. This disease affects several cultures, including cabbage and broccoli, among others. Proteome studies of this bacterium have been reported; however, most of them were performed using the bacterium grown under culture media conditions. Recently, we have analyzed the proteome of X. campestris pv. campestris during the interaction with the susceptible cultivar of Brassica oleracea and several proteins were identified. The objective of the present study was to analyze the expressed proteins of X. campestris pv. campestris during the interaction with the resistant cultivar of B. oleracea. The bacterium was infiltrated in the leaves of the resistant plant and recovered for protein extraction and two-dimensional electrophoresis. The protein profile was compared with that of the bacterium isolated from the susceptible host and the results obtained revealed a group of proteins exclusive to the resistant interaction. Among the proteins identified in this study were plant and bacterium proteins, some of which were exclusively expressed during the resistant interaction.

Irrigated agriculture is a key activity for the long-term survival of humanenvironmental systems and the assessment of agricultural sustainability has been gaining increasing relevance. In spite of several proposals developed, there is not a holistic approach that can be generally applied to assess sustainability of irrigated agricultural areas. In this paper we present a framework and associated indicators for the assessment of sustainability of irrigated agricultural systems in different contexts and locations. The framework covers four main sustainability dimensions: environmental integrity, economic resilience and profitability, social wellbeing and good governance. This approach was tested in 10 agricultural areas in eight different countries that represent a wide variety of situations in terms of agricultural development, environmental conditions, socio-economic settings and political contexts, but that share the fact that water use is a critical aspect for agricultural development. The obtained results illustrate the usefulness of the proposed framework to obtain a holistic picture of sustainability in irrigated agriculture areas, even in situations

The influence of exogenous IBA (indol-3yl-butyric acid) on root and callus formation was studied in shoots of the apple rootstocks A2 and M26. The shoots grown in vitro were derived originally from meristems of both juvenile and adult trees. Endogenous indol-3yl-acetic acid (IAA) concentrations in leaves and stems were correlated with the responses to applied IAA. After 30 subcultures shoots from A2 and M26 rooted easily, but A2 did so more readily and even without IBA. Treatment with IBA improved percentage rooting and number of roots in both rootstocks. Ex-adult and ex-juvenile shoots of A2 formed roots to the same extent. However, ex-adult shoots of A2 showed a higher IBA optimum for root number than ex-juvenile A2 and were also less sensitive to supra-optimal IBA concentrations. In contrast, in M26, there were no differences between ex-adult and ex-juvenile shoots. The results imply that rooting ability is associated more with differences between cultivars than with the origin of the explants. The best rooting occurred in ex-adult shoots ofA2 which had the lowest endogenous IAA concentration, while callus formation was correlated with high endogenous auxin concentration. Exadult A2 produced almost no callus even after exposure to high IBA concentrations (25 /M) whereas ex-adult M26 formed much more callus at 1/10 of the IBA concentration.

An in vitro propagation protocol has been developed for Hagenia abyssinica using original material from both juvenile and mature trees. Juvenile explants were obtained from seedlings, as well as shoots and meristems from 5 to 7-month-old greenhouse grown plants. Shoots collected from stem bases of five genotypes were used to establish cultures from mature trees. Explants of seedling origin were used to optimize the multiplication medium and growth regulators concentration. The best result was obtained from shoots subcultured on either MS or WPM medium supplemented with 4.4 lM BAP and 0.49 lM IBA. The initiated shoots from all the different explants were multiplied on these media. Rooting of shoots was achieved using MS medium containing macronutrients at one-third strength supplemented with 4.9 lM IBA. The shoots were kept in the dark for 4 days and transferred to medium of the same composition but containing 0.3% activated charcoal without growth regulators. Up to 100% rooting was achieved depending on genotype. Shoots multiplied on MS medium rooted better than those multiplied on WPM. Plantlets were transferred to pots containing a mixture of soil and perlite in a 2:1 ratio, respectively, and were maintained in the greenhouse. Increased irradiance reduced stem and leaf lengths and increased branch number of micropropagated plants. Abbreviations: BAP -6-benzylaminopurine; 2,4-D D -dichlorophenoxyacetic acid; GA 3 -gibberellic acid; IBA -indole-3-butyric acid; MS -Murashige and Skoog (1962); WPM -woody plant medium

Protoplast isolation from apple leaf tissue of in-vitro cultured shoots is possible if very young leaves from buds are used. Digestible leaves are found in apple shoots of the subculture AkerO 14 days after transferring the shoot and of M26 some days later. The yield of protoplasts is considerably improved if the apple shoots are cultured in a medium containing L-methionine (0.5 mM).

Populus × wilsocarpa, a hybrid of important ornamental value, cannot be seedpropagated, nor grafted, since a compatible rootstock has not been identified. A micropropagation protocol consisting of a series of steps was therefore developed to facilitate the commercial production of this species. The technique involved the transfer of swelling buds to a growth initiation medium with the following composition: N6 macronutrients, MS micronutrients and vitamins supplemented with 0.5mgl -~ BAP. The best buds were from dormant twigs, stored at 0-2 °C and then forced to burst prior to culture initiation. Shoot multiplication was on a basal WPM medium including 0.1 mg 1-l BAP and 0.001 mg 1-~ NAA. Shoot elongation and rooting was also on a basal WPM medium supplemented with 1.0 mg 1-GA 3 followed by a transfer to a peat-perlite mix in the greenhouse.

A highly efficient three-step protocol for in vitro propagation of Ensete ventricosum (enset) was developed that consisted of initiation, bud proliferation, and shoot elongation and rooting stages. At the initiation stage, it was crucial to use shoot tips (5-8 mm) with subtending corm tissues as explants to obtain growth. The addition of 0.5-1% (w/v) activated charcoal to the medium was essential to prevent phenol exudation which otherwise leads to the loss of cultures. During the bud proliferation stage, modified MS macronutrients and micronutrients together with a combination of cytokinins (1.6 mM naphthaleneacetic acid, 4.4 mM 6-benzylaminopurine, 23.2 mM kinetin, 22.6 mM N 6 2-isopentyladenine) was used. This novel composition of macronutrients was based on the analysis of leaf nutrient content of glasshouse-grown enset sprouts. Multiple bud formation on the enlarged corm tissue was induced only when the meristem region was wounded before transfer to the bud proliferation medium. Up to 75 healthy shoots per explant were produced, whereas unwounded explants produced, only one to two shoots per explant. A third stage with a low concentration of cytokinin enabled shoot elongation as well as root development. The plantlets were acclimatized with 100% success and they showed no apparent phenotypical deviation.

A suitable protocol for transformation has been developed for the apple rootstock Jork 9 using Agrobacterium tumefaciens strain EHA101A(pEHA101A) (pSCV1.6). Root formation was increased by transforming the rootstock with A. tumefaciens strain C58C1 (pGV3850)(pB-B:GUS), which contains the nptII, rolB and gus genes on the T-DNA. Transformation for all of the introduced genes was confirmed by polymerase chain reaction and Southern blot analyses. Of the 18 independent shoot lines obtained after transformation only ten contained at least one copy of intact T-DNA, while six lines were missing the gus gene and two lines were missing both the gus and rolB genes. The rooting experiments showed that introduction of the rolB gene increased root percentage and root number, giving 13.8 roots per shoot compared to 2.3 for untransformed shoots. More than two copies of the rolB gene decreased the number of roots and percentage of rooted shoots.

The apple rootstock M26 (Malus domestica) was infected with a binary vector system of Agrobacterium tumefaciens carrying the neomycin phosphotransferase II and Arabidopsis phyB genes. Thirteen transformed clones were obtained from 329 infected leaves. Five of the clones had a single copy integration, six clones had two copies, one clone had five copies and one of the clones had eight copies of the phyB gene integrated. No differences in rooting were found between transformed and untransformed plants. The stem length was reduced in nine of the 13 transgenic clones, and shoot, root and plant dry weights were reduced in all transformed clones compared with untransformed control plants. Northern analysis showed that the Arabidopsis phyB gene was expressed in the transformed clones.

The apple rootstock A2 can be readily propagated in vitro both in the juvenile and in the adult growth phase. Shoots were produced by meristem tip culture from the apple rootstock A2 in different growth phases. The influence of growth phases and different concentrations of PG and IBA was investigated as to rooting percentage, survival percentage, number of roots per rooted shoot, root length, shoot length and formation of callus. IBA at 15 μM without PG gave a significantly lower rooting percentage than 5 and 10 μM IBA. PG together with IBA stimulated rooting, the optimum concentrations of PG being, however, not the same for the different growth phases. For the adult growth phase, 10−4M PG promoted rooting, whereas 10−3M PG markedly inhibited rooting. In the juvenile growth phases, both 10−4 and 10−3M PG stimulated rooting. PG at 10−4M also increased the number of roots. The longest roots were obtained at 10−3M PG and 5 μM IBA. PG at 10−3M reduced callus formation at all IBA concent...

Enzymes, important to protein synthesis, were investigated in young and old leaves of Urtica dioiea. The plants, divided into two groups, were exposed to either 18-hour or 12-hour photoperiods. One group of plants from each pholoperiodic regime was subjected to an irradiance of 28 W x m" •', and the other group of plants to 42 W X m ^. The enzymes investigated were glutamate dehydrogenase (GDH), aspartate aminotransferase (glutamateoxaloacetate transaminase, GOT), and alanine aminotransferase (glutamate-pyruvate transaminase, GPT). GDH and GOT were determined by means of electrophoretic separation on polyacrylamide and spectrophotometric measurements. GPT was determined only by the latter method. Plants exposed to 18-hour photoperiods showed much higher GDH activity than did those exposed to 12-hour photoperiods. The activity of GDH also increased with leaf age. Besides one uniform NAD*-dependent GDH, two other NAD^-independent enzymes, showing GDH activity, were identified on polyacrylamide gel electrophoresis. The distribution of NADH and NAD^-dependent GDH activity between young and old leaves was similar under different growth conditions. The activity of GOT was insensitive to environmental changes. The results regarding GPT indicate that this enzyme responded to different photoperiods in the same way as GDH. A correlation coefficient of 0.928 was obtained for the relationship between GDH and GPT activity.

Pyricularia grisea (Cooke) Sacc. is the causal organism of blast, the most serious disease of rice because of its devastating nature, widespread distribution and existence of several physiologic races. It occurs in epiphytotic conditions in all major ricegrowing regions of the world, as well as in Italy. Nowadays, no strategies in current use are based on the dynamics of airborne conidia, the most important means of dissemination of the pathogen, and chemicals and management practices are the only means of blast control. However, blast forecasting may open the possibility of more rational use of fungicides and blast simulation models might prove to be useful in predicting the potential for the disease. During three growing seasons (2002, 2003 and 2004) and in two different rice fields located in Northern Italy (Sali Vercellese, Vercelli Province and Castello d’Agogna, Pavia Province), concentrations of P. grisea airborne conidia were measured using automatic spore traps. Temperature...

Tetraplasandra, Reynoldsia, and Munroidendron form a complex of closely related genera (14 species) distributed from Tahiti, Samoa, and the Marquesas, to the Hawaiian archipelago. In this paper, we investigate evolutionary relationships within this group using morphological and DNA sequence variation to test the monophyly of the Hawaiian species (the Tetraplasandra group), generic limits of Tetraplasandra, Reynoldsia, and Munroidendron, and the validity of current classifications. Parsimony analyses using two molecular markers, the internal transcribed spacer (ITS) and the 5S non-transcribed spacer (5S-NTS) of the nuclear rDNA genes, and 39 morphological and anatomical characters were conducted using all species of Tetraplasandra (excluding the recently resurrected species T. lydgatei), Reynoldsia, and Munroidendron, plus three species (four for morphological data) of the outgroup genus Gastonia. The results support a monophyletic Hawaiian Tetraplasandra group, a sister relationship between Munroidendron and R. sandwicensis, and a polyphyletic Reynoldsia. Here we build on previous molecular analyses of the Tetraplasandra group and propose the next steps necessary to recognize new generic boundaries. Changes in floral morphology within Tetraplasandra correspond to monophyletic groupings. Species with hypogynous flowers cluster together and species with floral characters suggestive of ornithophily cluster together.

Systematic relationships within the Hawaiian group Tetraplasandra A. Gray, Munroidendron Sherff and Reynoldsia sandwicensis A. Gray are investigated here based on parsimony analysis of nucleotide sequences from the internal transcribed spacer (ITS 1 and 2) regions and the non-transcribed spacer of 5S (5S-NTS) nuclear ribosomal DNA. Results indicate that Tetraplasandra, Munroidendron and Reynoldsia sandwicensis form a single monophyletic group, and that Reynoldsia A. Gray is paraphyletic. Both data sets support combining Reynoldsia sandwicensis with Munroidendron and treating it as distinct from Reynoldsia species outside Hawaii. Both data sets support two major clades: a Munroidendron/Reynoldsia sandwicensis clade and a Tetraplasandra clade, but they are discordant in relation to the monophyly of Tetraplasandra. 5S-NTS results support treating Tetraplasandra, Munroidendron and Reynoldsia sandwicensis as a single genus, whereas ITS results suggest that Tetraplasandra represents a dis...

Systematic relationships within the Hawaiian group Tetraplasandra A. Gray, Munroidendron Sherff and Reynoldsia sandwicensis A. Gray are investigated here based on parsimony analysis of nucleotide sequences from the internal transcribed spacer (ITS 1 and 2) regions and the non-transcribed spacer of 5S (5S-NTS) nuclear ribosomal DNA. Results indicate that Tetraplasandra, Munroidendron and Reynoldsia sandwicensis form a single monophyletic group, and that Reynoldsia A. Gray is paraphyletic. Both data sets support combining Reynoldsia sandwicensis with Munroidendron and treating it as distinct from Reynoldsia species outside Hawaii. Both data sets support two major clades: a Munroidendron/Reynoldsia sandwicensis clade and a Tetraplasandra clade, but they are discordant in relation to the monophyly of Tetraplasandra. 5S-NTS results support treating Tetraplasandra, Munroidendron and Reynoldsia sandwicensis as a single genus, whereas ITS results suggest that Tetraplasandra represents a distinct genus from Reynoldsia sandwicensis and Munroidendron. Tetraplasandra gymnocarpa (Hillebr.) Sherff is the only member of the Araliaceae with a completely superior ovary, and in T. kavaiensis (H. Mann) Sherff the ovary is partially superior. Together, they form a well-supported clade within the Hawaiian complex, confirming the hypothesis that in Tetraplasandra superior ovaries evolved in Hawaii from an epigynous ancestor.

This study investigates the incidence, severity, management practices, and in vitro control of Cercospora leaf spot (CLS) disease from groundnut (Arachis hypogaea L.) farms in Hong, Adamawa State, Nigeria, focusing on farmers' knowledge and practices. 60 farmers from six communities within the Hong Local Government Area were surveyed using structured questionnaires to assess their awareness and management strategies for CLS while seed, stem-bark and leaf extracts of A. indica were used at different concentrations (100, 200, 400 and 800 mg/ml) with a positive (Tebuconazole) and negative (5 ml of water) control for in vitro control trials. The results revealed that the majority of farmers lacked adequate knowledge about the disease and its causal agent, Cercospora arachidicola. Chemical control methods were the most commonly used, although not universally accessible or sustainable, while cultural control practices were rarely implemented. Disease incidence varied across locations, with Bangshika showing the highest incidence at 43.16%, while Pella had the lowest. Disease severity ranged from 41-60% in most farms, with some locations like Zhedinyi reporting higher severity (61-80%). In vitro antifungal investigation showed that seed extract of A. indica had the least radial mycelial growth (2.21 mm) compared to the stem-bark (3.47 mm) and the leaf (4.24 mm). These findings highlight the critical need for more effective disease management strategies, as well as farmer education on sustainable disease control measures. This study emphasizes the importance of integrated pest management (IPM) strategies for reducing groundnut yield losses due to CLS, more especially using A. indica as a biocontrol agent with recommendations for further research into identifying the active metabolites present in the botanical.