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We report the synthesis of two pyridinium‐based room temperature protic ionic liquids (PILs), pyridinium bisulfate, [HPyr][HSO4] and pyridinium sulphate, [HPyr]2[SO4] and investigation of the kinetics of their water sorption behaviour and its influence on their density, ionic conductivity, and potential windows. The PILs were synthesized by the reaction of pyridine base with an acid, H2SO4, under solventless conditions, and confirmed by FTIR spectroscopy and 1H NMR spectra. The appearance vibration bands in the 3095–3252 cm−1 range for −NH+ stretching in the FTIR spectra and a peak at a chemical shift of 8.439 ppm in the 1H‐NMR of the liquids confirm their synthesis as no such bands/peaks can be seen in that of the pure pyridine spectra. The PILs’ hygroscopic nature was examined by exposing them (5 mL each sample with exposed surface area 3.143 cm2) to air for varied time intervals at a relative humidity, RH=58±5 % and T=20±5 °C. Coulometric Karl‐Fischer (KF) titration was used to determine how much moisture each PIL sample absorbed at each time interval. The findings reveal that when the PIL was exposed to air for longer periods of time, more moisture was absorbed, and the results correspond well with the pseudo first‐order kinetic model. The densities and conductivities of several samples of the two PILs were examined, and it was discovered that as the percentage water content of the PILs grew, density decreased but conductivities increased. Furthermore, it was discovered that when temperature rose, the conductivity of each of the PILs increased, and the results fit well to the Arrhenius linear equation since the regression coefficient, R2, for each of the samples approached the perfect fit value of one. The electrochemical window (EW) data, the mechanism of moisture oxidation within the EWs of each PIL at Pt and Au electrodes, and the electrocatalytic role played by the Pt and Au surface oxides during ethanol oxidation are evaluated and discussed in light of their future sustainable energy applications. [ABSTRACT FROM AUTHOR]

Selenium is an essential trace element required for seleno-protein synthesis in many eukaryotic cells excluding higher plants. However, a substantial fraction of organically bound selenide in human nutrition is directly or indirectly derived from plants, which assimilate inorganic selenium into organic seleno-compounds. In humans, selenium deficiency is associated with several health disorders Despite its importance for human health, selenium assimilation and metabolism is barely understood in plants. Here, we analyzed the impact of the two dominant forms of soil-available selenium, selenite and selenate, on plant development and selenium partitioning in plants. We found that the reference plant Arabidopsis thaliana discriminated between selenate and selenite application. In contrast to selenite, selenate was predominantly deposited in leaves. This explicit deposition of selenate caused chlorosis and impaired plant morphology, which was not observed upon selenite application. However, only selenate triggered the accumulation of the macronutrient sulfur, the sister element of selenium in the oxygen group. To understand the oxidation state-specific toxicity mechanisms for selenium in plants, we quantified the impact of selenate and selenite on the redox environment in the plastids and the cytosol in a time-resolved manner. Surprisingly, we found that selenite first caused the oxidation of the plastid-localized glutathione pool and had a marginal impact on the redox state of the cytosolic glutathione pool, specifically in roots. In contrast, selenate application caused more vigorous oxidation of the cytosolic glutathione pool but also impaired the plastidic redox environment. In agreement with the predominant deposition in leaves, the selenate-induced oxidation of both glutathione pools was more pronounced in leaves than in roots. Our results demonstrate that Se-species dependent differences in Se partitioning substantially contribute to whole plant Se toxicity and that these Se species have subcellular compartment-specific impacts on the glutathione redox buffer that correlate with toxicity symptoms.

The widespread deficiency of iron (Fe) and sulfur (S) is becoming a global concern. The underlying mechanisms regulating Fe and S sensing and signaling have not been well understood. We investigated the crosstalk between Fe and S using mutants impaired in Fe homeostasis, sulfate assimilation, and glutathione (GSH) biosynthesis. We showed that chlorosis symptoms induced by Fe deficiency were not directly related to the endogenous GSH levels. We found dynamic crosstalk between Fe and S networks and more interestingly observed that the upregulated expression of IRT1 and FRO2 under S deficiency in Col-0 was missing in the cad2-1 mutant background, which suggests that under S deficiency, the expression of IRT1 and FRO2 was directly or indirectly dependent on GSH. Interestingly, the bottleneck in sulfite reduction led to a constitutively higher IRT1 expression in the sir1-1 mutant. While the high-affinity sulfate transporter (Sultr1;2) was upregulated under Fe deficiency in the roots, the low-affinity sulfate transporters (Sultr2;1, and Sultr2;2) were down-regulated in the shoots of Col-0 seedlings. Moreover, the expression analysis of some of the key players in the Fe–S cluster assembly revealed that the expression of the so-called Fe donor in mitochondria (AtFH) and S mobilizer of group II cysteine desulfurase in plastids (AtNFS2) were upregulated under Fe deficiency in Col-0. Our qPCR data and ChIP-qPCR experiments suggested that the expression of AtFH is likely under the transcriptional regulation of the central transcription factor FIT.

Phytohormone abscisic acid (ABA) is the canonical trigger for stomatal closure upon abiotic stresses like drought. Soil-drying is known to facilitate root-to-shoot transport of sulfate. Remarkably, sulfate and sulfide—a downstream product of sulfate assimilation—have been independently shown to promote stomatal closure. For induction of stomatal closure, sulfate must be incorporated into cysteine, which triggers ABA biosynthesis by transcriptional activation of NCED3. Here, we apply reverse genetics to unravel if the canonical ABA signal transduction machinery is required for sulfate-induced stomata closure, and if cysteine biosynthesis is also mandatory for the induction of stomatal closure by the gasotransmitter sulfide. We provide genetic evidence for the importance of reactive oxygen species (ROS) production by the plasma membrane-localized NADPH oxidases, RBOHD, and RBOHF, during the sulfate-induced stomatal closure. In agreement with the established role of ROS as the second messenger of ABA-signaling, the SnRK2-type kinase OST1 and the protein phosphatase ABI1 are essential for sulfate-induced stomata closure. Finally, we show that sulfide fails to close stomata in a cysteine-biosynthesis depleted mutant. Our data support the hypothesis that the two mobile signals, sulfate and sulfide, induce stomatal closure by stimulating cysteine synthesis to trigger ABA production.

Cadmium (Cd) is toxic to the ecosystem even at low concentrations. To mitigate Cd toxicity as well as to enhance plant growth, endophytes extracted from different sources have been effectively used. In the current study, the role of an endophytic bacterial strain Serratia sp. IU01, in alleviating Cd toxicity and promoting growth was evaluated in Brassica juncea in the hydroponic system. Cd stress significantly reduced the growth attributes (root/shoot length and biomass) of the host plant in comparison to control plants. A significant increase was observed in the shoot, root length and biomass of B. juncea plants inoculated with Serratia sp. IU01 (9.8 ± 0.28 cm, 12.16 ± 1.44 cm, 299.5 ± 39.5 mg, respectively) compared to control (8.6 ± 0.28 cm, 7.16 ± 0.76 cm, 125.27 ± 5.40 mg, respectively), sole Cd-treated (5.5± 0.5 cm, 4.33± 1.15 cm, 103.73 ± 7.18 mg, respectively), and inoculated Cd-treated plants (5.67± 0.58 cm, 6± 1.53 cm, 137.33 ± 6.66 mg, respectively). Growth parameters were retrieved in inoculated plants under Cd stress but the differences were non-significant in comparison to the un-inoculated Cd-treated plants. High-performance liquid chromatography (HPLC) analysis revealed significantly elevated steady-state levels of one of the most abundant versatile antioxidant molecules in the cell i.e., glutathione (GSH) in response to Cd stress. However, under Cd stress, inoculation of the plants with Serratia sp. IU01 led to a significant decrease in roots' GSH contents (75 ± 15.56 pmol mg-1 FW) compared with the un-inoculated Cd-treated (141 ± 7.2 pmol mg-1 FW) and control set of plants (123.6 ± 1.2 pmol mg-1 FW) presumably via the release of antioxidants by the endophytes in the roots of internal tissues of the host plant. These results demonstrated the potential of Serratia sp. IU01 in mitigating Cd-induced toxicity and promoting plant growth in Cdpolluted environments. [ABSTRACT FROM AUTHOR]

This research was conducted to determine inbreeding depression in S1 maize lines for reproductive and yield related traits, at NWFP Agricultural University, Peshawar, Pakistan, in two successive seasons during 2002. Maize variety"Pahari" was selfed for one generation and 63 S1 lines were evaluated using "lattice square design" with two replications along with the parental population. Days to mid silking and mid pollen shed (anthesis), plant height and ear height (cm), and 200 grain weight (g) showed inbreeding depression with varying degrees. Severe inbreeding depression was observed for yield with the average of 709 kg ha-1. Inbreeding depression for 200 grains weight averaged 19 g, while for plant height and ear height it was calculated as 33 and 16 cm. Inbreeding depression for days to mid silking and pollen shed was lower as compared to morphological and yield components. Silking and pollen shed were delayed by 1.8 and 1.5 days on the average, respectively, as compared to the parental variety. Yield was significantly correlated with all maturity and morphological characters. Maturity characters were positively and significantly correlated with each other, showing good synchronization in maturity characters, while they were negatively and significantly correlated with yield components.

The experiment was conducted at NWFP Agricultural University, Peshawar to study heterosis and inbreeding depression in 7×7 half diallel crosses of sunflower. The planted materials consisted of parental inbred lines, their F1 hybrids and F2 populations using randomized complete block design with three replications. Data were recorded on yield and other important agronomic characters. Significant genetic differences were observed among the parents, their F1 hybrids and F2 populations for all the characters under study. Yield and leaf area showed highly significant heterosis in F1 hybrids ranging from 102 to 309% and46.3 to 163.9%, respectively, while inbreeding depression in the F2 population ranged from 17-71% and -9.7-43%, respectively. Leaves per plant showed low level of heterosis in F1 hybrids (-0.9 to 39.7%), whereas the effect of inbreeding depression in F2 population was comparatively high (1.1 to 22.2%) for this character. The parent RHA-822 proved itself to be a good general combiner by making higher contribution towards heterosis both in F1 hybrids and in F2 populations.

Selenium (Se) hyperaccumulation, the capacity of some species to concentrate Se to levels upwards of 0.1% of dry weight, is an intriguing phenomenon that is only partially understood. Questions that remain to be answered are: do hyperaccumulators have one or more Se-specific transporters? How are these regulated by Se and sulfur (S)? In this study, hyperaccumulator Stanleya pinnata was compared with related non-hyperaccumulator Brassica juncea with respect to S-dependent selenate uptake and translocation, as well as for the expression levels of three sulfate/selenate transporters (Sultr) and three ATP sulphurylases (APS). Selenium accumulation went down ~10-fold with increasing sulfate supply in B. juncea, while S. pinnata only had a 2-3-fold difference in Se uptake between the highest (5mM) and lowest sulfate (0mM) treatments. The Se/S ratio was generally higher in the hyperaccumulator than the non-hyperaccumulator, and while tissue Se/S ratio in B. juncea largely reflected the ratio in the growth medium, S. pinnata enriched itself up to 5-fold with Se relative to S. The transcript levels of Sultr1;2 and 2;1 and APS1, 2, and 4 were generally much higher in S. pinnata than B. juncea, and the species showed differential transcript responses to S and Se supply. These results indicate that S. pinnata has at least one transporter with significant selenate specificity over sulfate. Also, the hyperaccumulator has elevated expression levels of several sulfate/selenate transporters and APS enzymes, which likely contribute to the Se hyperaccumulation and hypertolerance phenotype. [ABSTRACT FROM AUTHOR]

Morphological and anatomical study of eight prevalent weed species belonging to seven different families present in maize fields of Mir Ali, North Waziristan Agency, Pakistan was conducted during August and September of 2009 and 2010. The study comprised of noxious weeds like, Alhagi maurorum, Amaranthus viridis, Conyza bonariensis, Digera arvensis, Lippia nodiflora, Oxalis corniculata, Polygonum barbatum and Portulaca oleracea at full vegetative growth stages. Permanent microscopic preparations were made to measure and analyze elements of the anatomy of stems and root (epidermis, cortex, collenchyma, central cylinder and diameter). It was concluded that, Alhagi maurorum equipped with elaborate vascular bundles both in root and stem clarified its adaptation in the severe rainfed climate of the area. Because of its significant seed dispersal, it is acclimatized throughout the area. Other weeds like Amaranthus viridis, Conyza bonariensis, Digera arvensis, Lippia nodiflora, Oxalis corniculata, Polygonum barbatum and Portula caoleracea having the peculiar characteristics of typical mesophyte are well adopted and can complete their life cycle along with the maize crop. Due to special morphological and anatomical features of majority of the species studied, the capacity of rapid absorption of water along with minerals from the soil are enough to compensate the rapid loss of water, and thus can be easily adopted along with the maize crop. [ABSTRACT FROM AUTHOR]

Growth potential of three indigenous landraces (Kulat brown, Kulat white, Mothi) and two improved varieties (NARC-II and Swat-84) of soybean planted under four dates from April to July during 2004 and 2005 growing season were compared. Relative growth rate (RGR) was determined at 1) early vegetative growth 2) bloom and 3) seed filling stages and seed yield. Differences in RGR due to planting dates, varieties and planting dates x varieties were significant at early vegetative and bloom stages. At seed filling stage, varieties and planting dates x varieties did not show variation in RGR. Maximum RGR at the early vegetative growth, bloom and seed filling stages was recorded for July (89mg g-1 day-1) May (58.8 mg g-1day-1) and April (8 mg g-1day-1) planted crops, respectively. Similarly maximum seed yield (1459 kg ha-1) was observed in April planted crop. The average RGR recorded for early vegetative growth, bloom and seed filling stages was 71.6, 40.1 and 4.8 mg g-1day-1 respectively. At early vegetative growth, maximum RGR (79.6 mg g-1day-1) was observed for Kulat brown. At bloom, maximum RGR (46.3 mg g-1day-1) was recorded for Kulat white. At seed filling no difference was observed in RGR among the varieties. The overall average RGR for the landraces (42.4 mg g-1day-1) was greater than the RGR of improved varieties (34.1 mg g-1day-1). Improved varieties produced maximum seed yield (1306 kg ha-1) as compared to landraces (1245 kg ha-1). [ABSTRACT FROM AUTHOR]

Phytohormone abscisic acid (ABA) is the canonical trigger for stomatal closure upon abiotic stresses like drought. Soil-drying is known to facilitate root-to-shoot transport of sulfate. Remarkably, sulfate and sulfide—a downstream product of sulfate assimilation—have been independently shown to promote stomatal closure. For induction of stomatal closure, sulfate must be incorporated into cysteine, which triggers ABA biosynthesis by transcriptional activation of NCED3. Here, we apply reverse genetics to unravel if the canonical ABA signal transduction machinery is required for sulfate-induced stomata closure, and if cysteine biosynthesis is also mandatory for the induction of stomatal closure by the gasotransmitter sulfide. We provide genetic evidence for the importance of reactive oxygen species (ROS) production by the plasma membrane-localized NADPH oxidases, RBOHD, and RBOHF, during the sulfate-induced stomatal closure. In agreement with the established role of ROS as the second messenger of ABA-signaling, the SnRK2-type kinase OST1 and the protein phosphatase ABI1 are essential for sulfate-induced stomata closure. Finally, we show that sulfide fails to close stomata in a cysteine-biosynthesis depleted mutant. Our data support the hypothesis that the two mobile signals, sulfate and sulfide, induce stomatal closure by stimulating cysteine synthesis to trigger ABA production. [ABSTRACT FROM AUTHOR]

Genetic variations among eight Pakistani tomato (Solanum lycopersicum L.) accessions were investigated using morphological traits and randomly amplified polymorphic DNA (RAPD) primers. Significant differences among accessions were observed for most of the quantitative and qualitative morphological traits. The RAPD-PCR assay amplified a total of 39 different alleles with 33 polymorphic alleles resulting in an 84.25% rate of polymorphism among eight tomato accessions. The most informative primers were B06 and H05 by revealing the maximum number of bands in the germplasm. The dendrogram for the morphological traits classified the germplasm into a single larger cluster except for genotype 17880. The dendrogram constructed for the molecular data clearly segregated the germplasm into two clusters. The accessions 17862 and 17870 were placed in the small cluster while the rest of the accessions were grouped together in the larger cluster. Genetic similarity ranged from 0.31 to 0.83 with an average of 0.68 for all evaluated accessions. [ABSTRACT FROM AUTHOR]

Caprine mycoplasmosis is an important infectious respiratory complication lead to significant health issue and causes heavy economic losses in small ruminant population throughout the world. The study was designed to identify and characterize the pathogenic member of mycoplasma cluster the Mycoplasma capricolum sub specie capripneumoniae (Mccp) isolated from goat suffering from respiratory syndrome in the natural outbreak. The study was carried out during November, 2013 to April, 2015 in the Khyber Pakhtunkhwa (KPK), Pakistan. A total of 825 samples from nasal discharge, tracheal swab, pleural fluid and lung tissue were collected from goat clinically suspected for Contagious Caprine Pleuro Pneumonia (CCPP). The samples taken in PPLO transport media were cultured on modified Hay Flick media and incubated at 37° C with 5% CO2 for 7-12 days. Out of total 267 (32.36%) were positive for mycoplasma growth showing mass turbidity, whirling movement in culture broth and typical fried egg colonies in agar media. The positive culture was identified through biochemical assay and confirmed as Mccp through PCR by using cluster and specie specific primers. Out of 267 positive samples 55 (20.59%) were confirmed as Mycoplasma mycoides cluster and 23 (8.61%) were identified as Mccp. Sequencing of the 16-S rRNA gene blast search revealed 99% sequence homology with Mccp compared with eight available sequences at NCBI. The presence of Mccp was for the first time reported in small ruminants of Khyber Pakhtunkhwa. [ABSTRACT FROM AUTHOR]