Alternanthera Pungens Research Articles

A Flavonoid-rich Fraction of Alternanthera pungens Ameliorates Hyperglycaemia -mediated Memory Dysfunction in Diabetic Rats

The central nervous system (CNS) undergoes alterations due to persistent hyperglycemia and cholinergic dysfunction, leading to cognitive impairment associated with diabetes (T2DM). Animal studies have shown that acetylcholinesterase (AChE) inhibitors and anti-diabetics are effective. Considering the impressive potential of natural products in treating DM and AD, the present research set out to assess the neuroprotective effects of a methanolic extract of Alternanthera pungens (MEAP) against cognitive impairment in mice caused by hyperglycemia. Hence, we used the mobile workforce management (MWM) and enterprise performance management (EPM) assays to analyze for cognitive impairment in diabetic rats. 30 days after the initiation of T2DM, rats had hyperlipidemia, increased escape latency in EPM tasks, and decreased time spent in the TSTQ during probe trials in the MWM. They also displayed notable and persistent hyperglycemia throughout training trials. Changes in blood glucose, lipid, and liver profiles, as well as performance in MWM and EPM tests, were averted in STZ-induced T2DM rats treated with MEAP (200 and 400 mg/kg). In a separate series of experiments, flavonoids (i.e., quercetin and rutin) were detected by the standardization of the extract using high performance thin layer chromatography (HPTLC). Inhibitory actions against alpha-amylase and alpha-glucosidase demonstrate that both of these flavonoids are potent antidiabetic agents that reduce intestinal glucose absorption. Lastly, the inclusion of these flavonoids in the extract from A. pungens is responsible for its action, suggesting that it may provide a novel strategy for preventing cognitive deterioration in diabetes.

Micromorphological Sculptural Diversity in Foliar Epidermis and Trichomes Features among Invasive Species.

This study examines the role of light microscopic (LM) and scanning electron microscopic (SEM) micromorphological traits of the epidermis in identifying and classifying invasive plants. SEM was conducted to increase our understanding of microscopic qualities that are not visible in light microscopy and to elucidate unclear affinities among invasive species. The study examines invasive species' morphological and anatomical characteristics from the Pothohar Plateau of Pakistan for the first time. The results showed that various micromorphological features are very useful for species' accurate identification. Adaxial and abaxial surfaces of leaves showed variations in subsidiary cells, glands, anticlinal wall patterns, stomata, and epidermal cells. Epidermal cell shapes observed were irregular, elongated, rectangular, and polygonal. Epidermal cells having maximum length were calculated in Stellaria media (126.3 μm) on adaxial side. On the abaxial surface, the minimum length was noticed in Eucalyptus camaldulensis (28.5 μm). Both glandular and nonglandular trichomes were examined, ranging from unicellular to multicellular. Most of the investigated specimens of leaves were amphistomatic, while some were hypostomatic, like Alternanthera pungens, Calotropis procera, Cannabis sativa, Lantana camara, and Thevetia peruviana. Leaf epidermal morphology contains numerous useful systematic features for accurate identifications of plant species. The micromorphological attributes under observation provide a standard criterion to the researcher for identifications of invasive flora in future morpho-taxonomic studies.

Functionalization of ampicillin and gentamicin with biogenic copper nanoparticles (CuNPs) remodel antimicrobial and cytotoxic outcome against MDR clinical isolates.

The present study reports the functionalization of antibiotic-conjugated Alternanthera pungens and Trichodesma indicum copper nanoparticles (CuNPs). Initially, antibiotic profiling of multi-drug resistant (MDR) clinical isolates against five antibiotics was verified and then gentamicin and ampicillin conjugates of CuNPs were prepared. Biosynthesized nanostructures were characterized through UV-visible spectroscopy, Fourier-transformed infrared spectroscopy, X-ray diffraction and scanning electron microscope. Biogenic synthesized CuNPs displayed highest antibacterial activity (24.0-31.3mm inhibition zones) when capped with gentamicin as compared to the ampicillin-conjugated NPs which showed resistance against most of the bacterial species. A. pungens-derived conjugates of gentamicin (CuAp-GNT) along with the vehicle revealed 4.86 ± 0.20% and 4.25 ± 2.96% hemolytic potential and highest MDA production in S. typhimurium (3.18 ± 1.52µg/mL and 6.31 ± 3.49µg/mL) and K. pneumoniae (2.99 ± 0.90µg/mL and 4.06 ± 1.20µg/mL). Similarly, CuAp-GNT also showed highest DNA protection ability by displaying 1342.99 ± 11.87 band intensity. All-inclusive, CuAp showed more promising effects when conjugated with gentamicin indicating that capping of gentamicin with the active components of the plant-based copper nanostructures increases the antibacterial capacity of the drug. Hence, conjugation of antibiotics with bio-based sources offers great potential for identifying potent drug leads.

Phytochemical Study and In Vitro Biological Activities of Hibiscus panduriformis Burm. f. (Malvaceae), Alternanthera pungens Kunth (Amaranthaceae), and Wissadula rostrata (Schumach.) Hook. f. (Malvaceae).

The present study investigated the phytochemical content of Hibiscus panduriformis, Alternanthera pungens, and Wissadula rostrata and assessed their radical scavenging and anti-inflammatory properties. n-Hexane, dichloromethane (DCM), ethyl acetate, and methanol extracts were prepared from the powdered plant parts. The phytochemical analysis was performed using qualitative high-performance thin-layer chromatography, and polyphenols were quantified using well-established methods. The anti-inflammatory effect was by lipoxygenase inhibition, while the antiradical impact was evaluated through DPPH and ABTS radicals. Steroids, triterpenoids, flavonoids, and tannins were identified in the three plants. The highest phenolic content (95.67 ± 2.19 mg gallic acid equivalent/g) was obtained in the methanolic extract of W. rostrata, while the lowest was measured in H. panduriformis. H. panduriformis was found to be highly rich in flavonoids (61.22 ± 0.09 mg rutin equivalent/g), condensed tannins (62.53 ± 0.03 mg catechin equivalent/g), and hydrolyzable tannins (125.1 ± 1.02 mg tannic acid equivalent/g). The methanolic extract of H. panduriformis displayed the greatest antilipoxygenase activity with an IC50 value of 8.78 ± 1.05 μg/mL. It should be noted that although a moderate to low effect was observed, the extracts were more likely to scavenge DPPH (IC50 values ranged from 0.106 ± 0.010 to 1 mg/mL) than ABTS radicals. There was a strong to moderate correlation between the antilipoxygenase and DPPH radical scavenging effects of the methanolic extracts and total phenolic content (antilipoxygenase, r = 0.7175; DPPH, r = 0.9376). Furthermore, it is worth noting that this is the first report investigating the phytochemical analysis and in vitro biological properties of Hibiscus panduriformis. The results highlighted the richness of this plant in polyphenols and demonstrated its high and moderate effects on lipoxygenase and DPPH radicals, respectively. To this intent, further in vivo and in vitro studies on this plant, along with exhaustive phytochemical analysis, are needed.

Ethnobotanical inventory and medicinal perspectives of herbal flora of Shiwalik mountainous range of District Bhimber, Azad Jammu and Kashmir, Pakistan.

The present study was carried out to document traditional ethnobotanical knowledge (TEK) of herbal flora of District Bhimber, Azad Jammu and Kashmir (AJK), Pakistan to explore medicinal potential of wild indigenous plants (WIPs) for drug discovery. The research data was conducted during years 2015–2017 using questionnaire proforma employing structured and semi-structured interview models. The informants belonged from indigenous communities comprising of both genders with age ranging from 35–105 years. The interviews were conducted using local translator or guide who knew the dialects of all local languages. The study produced ethnobotanical inventory of 173 herbal species belonging to 45 families and out of these Poaceae was dominant family with 27 species. It was explored that maximum herbal species depicted multi-usage especially food, fodder and fuel. Among 173 herbal plant species, 69% species were used as fodder, 72% species as fuel source, 9.8% as ethnoveterinary medicines, 16% for home construction, 12% for cosmetics, 5.2% as honeybee plants and 2.7% were used as fiber source by the local people. Many local plants have been in promulgation for cure of different diseases in traditional cultures such as for cure of stomach problems, cough, cancer, jaundice, kidney diseases, diabetes, snake biting and tooth problems. Different parts of plants such as leaf, root, stem bark, flower, seed and gums are used for the treatment of different diseases by the local people. The major aliments being cured are classified into 12 disease categories by using informant consensus factor (ICF) protocol. According to ICF, the highest numbers of plant species were used against wound healing, snake bite, skin diseases, eye diseases and asthma. Fidelity level (FL) was assessed to check the reliability and use consistency of herbal drugs by the indigenous communities of the study area. The use value index (UVI) of different herb species ranged from 0.29 to 0.57 while the highest value was calculated for Alternanthera pungens L. (UVI: 0.57). Relative frequency of citation (RFC) value was calculated on the bases of the response of the interviewees recorded during survey in correlation with authenticating of traditional data. The RFC values represented the relative popularity of individual species in study area according to their use values. The highest value was calculated for Alternanthera pungens L. (0.90) and followed by Achyranthes aspera L. (0.80. The study reveals that many species are known for commonly used in traditional ethnomedicines (TEMs). Due to different biotic and abiotic factors in conjunction with climatic changes many herbal flora of Shiwalik mountain range (SMR) of District Bhimber of AJK is under threat. The factors like habitat loss, overgrazing, construction of communication infrastructure, silviculture practices, shelter construction (houses) and other more domestic use of wild land by clearing wild lands are boosting towards plant biodiversity loss. There is dare need to work on comprehensive exploration of TEMs to discover neo drugs from wild indigenous plants and do work for conservation of wild flora of the area for future generations.

Pollen morphology of some species in family Amaranthaceae from Thailand

Abstract. Saensouk S, Saensouk P. 2021. Pollen morphology of some species in family Amaranthaceae from Thailand. Biodiversitas 23: 601-611. The aim of this study was to study the pollen morphology of 14 species, eight genera from the family Amaranthaceae in Thailand by the applied acetolysis method and it was taken under light and scanning electron microcopies. All pollen grains had monad, radial symmetry and apolar. The pollens in this study can be divided into several groups based on shape, size, aperture, mesoporia, the character of aperture, and exine sculpturing. The sizes of the pollen can be divided into three groups, i.e., very small pollen group, small pollen group, and medium pollen group. The shapes of the pollen can be divided into three groups, i.e., spheroidal, pentagon, and dodecahedric. Exine sculpturing can be divided into three groups, i.e., granular, macrogranular, and microspine. The pollen in this study can be divided into five groups based on the character of the aperture, i.e., aperture with convex circular-like shape, aperture with deeply collapsed circular-like shape, aperture with collapsed circular-like shape, aperture with collapsed pentagon-like shape, and 6-angular element or hexagon-like shape. The pollen in this study can be divided into three groups based on the mesoporia, i.e., mesoporia broadly flat, mesoporia moderately and broadly vaulted, and mesoporia narrow and highly vaulted. The number of apertures was found to be between 12-54 apertures per pollen. The aperture diameters of Amaranthaceae pollen in this study ranged from 0.5-5 µm. The exine thickness of the pollen in this study was 1.12±0.04 - 2.14±0.31 µm. The pollen character of this study can be divided into eight types, i.e., Achyranthes-type, Alternanthera-type, Amaranthus-type, Celosia-type, Cyathula-type, Gomphrena-type, Ouret-type, and Psilotrichum-type. The pollen characteristic of Alternanthera pungens Kunth, A. Sessilis (L.) R. BR., Amaranthus blitum subsp. oleraceus (L.) Costea, Cyathula prostrate (L.) Blume., Ouret sanguinolenta (L.) Kuntze, and Psilotrichum ferrugineum (Roxb.) Voigt were reported for the first time.

Conversion of waste seed oil of Citrus aurantium into methyl ester via green and recyclable nanoparticles of zirconium oxide in the context of circular bioeconomy approach.

In the current scenario of energy crises and depleting fossil fuels, there is need of sustainable and cheaper interventions with green technology to address these obstinate glitches. Biodiesel produced from waste, non-edible seed oils is a cleaner, green and alternate source of fuel for diesel engines which can possibly add to circular bioeconomy. In this study, Citrus aurantium a novel, nonedible and waste seed oil (38% w/w) producing feedstock was subjected to biodiesel synthesis using recyclable zirconium oxide nano particles synthesized with Alternanthera pungens aqueous leave extract. Maximum yield of 94% was obtained through optimized reaction parameters of methanol to oil molar ratio 6:1, reaction time 120min, temperature 87.5°C and catalyst loading of 0.5wt% using Response Surface Methodology. Green nano particles of zirconium oxide were characterized via Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and Energy diffraction X-Ray (EDX) while; physiochemical characterization of synthesized biodiesel was carried through Fourier-transform infrared spectroscopy (FTIR), Gas Chromatography/Mass spectroscopy (GC/MS), and Nuclear magnetic resonance (NMR 1H and 13C). Fuel properties of methyl ester met international standards of ASTM D-6571, EN 14214 and China GB/T 20828-2007. It was concluded that biodiesel production from Citrus aurantium waste and non-edible seed oil can be efficiently employed for generation of renewable energy which would further provide assistance in transformation of linear economy to circular bioeconomy.

Phytochemical and Pharmacological Evaluation of Alternanthera pungens

The aim of the present study was to evaluate pharmacognostical and antimicrobial, antioxidant, anti-inflammatory activity of ethanolic leaf extracts of Alternanthera pungens. The collected plants were washed, dried, cut and ground into coarse powder and macerated with ethanol and extract was dried by rotary vacuum. Phytochemical screening of ethanol extract revealed the presence of steroids, flavonoids, saponins, glycoside, phenols, and proteins. However, alkaloids and glycosides were absence in this species. The ethanolic extract of whole plant of A. pungens was subjected to column chromatography to separate pure compounds. Invitro antioxidant activity was performed by 2, 2 -diphenyl- 1- picrylhydrazyl (DPPH) assay, hydroxy radical scavenging method and superoxide radical scavenging activity. The ethanolic extract of A. pungens was evaluated against antimicrobial activity against two fungal and four bacterial strains. The extracts showed remarkable inhibition of zone of bacterial and results were comparable with that of standard drugs against the organism tested.

THE CHEMICAL CONSTITUENTS' OF THE LEAVE ESSENTIAL OIL OF ALTERNANTHERA PUNGENS (KUNTH)

Alternanthera pungens Kunth commonly called khaki weed is from the family Amaranthaceae. It is a herbaceous perennial plant that has stems prostrate, rarely rising and about 10-50 cm long. The work was carried out due to the scarcity of information on the volatile constituents from the plant leaves despite works on the flower and other parts. The extraction of the essential oils from the dried leaves was carried out by the hydro distillation method using an all-glass Clevenger apparatus. The extracted oils were then analyzed using gas chromatography-mass spectrometry (GC-MS). A total of twelve constituents' representing 93.39% of A. Pungens oil with a yield of 0.4% (v/w) was obtained. The analysis of the GC-MS results of the leaf oil showed that it was dominated by â-ionone (42.18%) and hexahydrofarnesyl acetone (15.53%), others in trace amounts include; methyl palmitate (6.13%), 1octadecyne (4.72%), undecane (3.73%), para-mentha-1, 3, 8-triene (3.65%), isophytol (3.21%), ?cadinene (3.06%), 1, 2-dimethyl cyclooctene (3.05%), para-cymene (2.96%), phytol (2.67%) and neophytadiene (2.50%). The common classes of compounds present in the leaves oil are aceto monocyclic monoterpenoid (42.18%), sesquiterpenoids (18.59%), hydrocarbons (11.50%), diterpenoids (8.38%), monoterpenes (6.61%) and fatty acids (6.13%).The constituents and the compositional pattern of essential oil identified from the leaves of Alternanthera pungens grown in Nigeria differ quantitatively and qualitatively from previously reported member of the genus and the presence of sesquiterpenoid as one of the major components of the oils justify the traditional use of the plants in treating pains, headaches and inflammations.

THE CHEMICAL CONSTITUENTS' OF THE LEAVE ESSENTIAL OIL OF ALTERNANTHERA PUNGENS (KUNTH)

Alternanthera pungens Kunth commonly called khaki weed is from the family Amaranthaceae. It is a herbaceous perennial plant that has stems prostrate, rarely rising and about 10-50 cm long. The work was carried out due to the scarcity of information on the volatile constituents from the plant leaves despite works on the flower and other parts. The extraction of the essential oils from the dried leaves was carried out by the hydro distillation method using an all-glass Clevenger apparatus. The extracted oils were then analyzed using gas chromatography-mass spectrometry (GC-MS). A total of twelve constituents' representing 93.39% of A. Pungens oil with a yield of 0.4% (v/w) was obtained. The analysis of the GC-MS results of the leaf oil showed that it was dominated by â-ionone (42.18%) and hexahydrofarnesyl acetone (15.53%), others in trace amounts include; methyl palmitate (6.13%), 1octadecyne (4.72%), undecane (3.73%), para-mentha-1, 3, 8-triene (3.65%), isophytol (3.21%), ?cadinene (3.06%), 1, 2-dimethyl cyclooctene (3.05%), para-cymene (2.96%), phytol (2.67%) and neophytadiene (2.50%). The common classes of compounds present in the leaves oil are aceto monocyclic monoterpenoid (42.18%), sesquiterpenoids (18.59%), hydrocarbons (11.50%), diterpenoids (8.38%), monoterpenes (6.61%) and fatty acids (6.13%).The constituents and the compositional pattern of essential oil identified from the leaves of Alternanthera pungens grown in Nigeria differ quantitatively and qualitatively from previously reported member of the genus and the presence of sesquiterpenoid as one of the major components of the oils justify the traditional use of the plants in treating pains, headaches and inflammations.

Germinable weed seed-bank response to plant residue application and hand weeding under two contrasting tillage systems in a granite-derived clay loam soil in Zimbabwe

High levels of weed infestation are among the major reasons for the limited adoption of conservation agriculture techniques by farmers in sub-Saharan Africa. This study investigated the effects of plant residue application (zero: NR, low: LR, medium: MR and high: HR) and hand weeding (twice: TWI, thrice: THR, four times: FOU and clean weeding: CLE) under two tillage systems (basin planting: BASIN, and conventional tillage: CT) on weed seed density in a clay loam soil at Chinhoyi University of Technology experimental farm, Zimbabwe. During 2014/15, the number of germinable Amaranthus hybridus L. seeds was higher in BASIN+NR+THR and BASIN+MR+TWI than other treatments. Germinable propagules of Cyperus L. spp. were fewer in NR+FOU and NR+CLE than NR+TWI and NR+THR plots. In 2015/16, TWI resulted in an increase of 52.3−79.5% of the number of germinable A. hybridus seeds compared to THR, FOU and CLE. Germinable weed seeds increased by 67.1% for Alternanthera pungens Kunth and 164.8% for Galinsoga parviflora Cav. in the surface compared to the subsurface layers of BASIN but were evenly distributed in CT. The results suggest that cultural practices exert selection pressure on individual weed species which may change the weed species composition in the soil seed bank.

First Report of Alternanthera Mosaic Virus Infecting Epiphyllum spp.

Epiphyllum spp. (orchid cactus) is a group of epiphytic plants in the cactus family grown as flowering ornamentals. Symptoms of virus infections are frequently observed in them (Chessin 2002). In 2015, 13 Epiphyllum hybrids (seven with chlorotic ring spots, mottle, or mosaic symptoms and six without any symptoms) were tested by RT-PCR/PCR using specific or group primers for cactus mild mottle virus, cactus virus X, impatiens necrotic spot virus, saguaro cactus virus, zygocactus virus X, badnavirus, and potyvirus, respectively. None of these viruses were detected from a hybrid ‘Dragon Heart’ showing irregular chlorotic patches on its stems. This plant was tested in subsequent high-throughput sequencing analysis for identification of viruses and viroids. Total RNAs were extracted from stem tissue using an RNeasy Plant Mini Kit (Qiagen, Germantown, MD) and subjected to Illumina NextSeq 500 sequencing (SeqMatic, Fremont, CA). Analysis of the RNA reads of 75 nucleotides (nt) revealed the presence of alternanthera mosaic virus (AltMV, 213,038 reads, 2,445x) and a new cavemovirus in the Dragon Heart plant. Infection of AltMV-DH was confirmed by RT-PCR using AltMV-detF6c (5′-TCACYCAGGAACAGATGRACG-3′) and AltMVR6 (5′-TAGGTCTACAGAAGCGGAAGC-3′). To obtain the genomic sequence of this AltMV isolate, RT-PCR was conducted using six overlapping primer pairs designed according to the alignment of the AltMV type species (GenBank no. NC_007731) and AltMV contig obtained in this study. The RT-PCR amplicons were cloned into a pGEM-T easy vector (Promega, Fitchburg, WI) and sequenced (MCLAB, South San Francisco, CA). The complete genomic sequence of 6,633 nt (GenBank no. MH423501) was assembled from six overlapped amplicon sequences. BLAST search showed that this isolate had the highest nucleotide sequence identity of 94 to 95% with four AltMV isolates available in the GenBank databases. Stem tips from the Dragon Heart plant were grafted onto three plants of hybrid ‘King’s Ransom’, a hybrid that tested negative for the nine viruses included in this study. Three grafted plants showed mottling symptoms 6 months after inoculation. AltMV was detected in new growth of all three grafted plants, indicating the virus was graft transmissible. A total of 30 additional Epiphyllum hybrids were tested by RT-PCR, and AltMV was detected from four symptomatic hybrids (‘Clarabelle’, ‘Mark Twin’, ‘Professor Ebert’, and ‘Over the Top’) and two asymptomatic hybrids (‘Cream and Gold’ and ‘Montrose’). AltMV is a member of the genus Potexvirus in the family Alphaflexiviridae. The virus was first reported from Alternanthera pungens in Australia (Geering and Thomas 1999) and has been found from plants of at least eight families in the United States, Europe, and Brazil (Hammond and Reinsel 2015). To our knowledge, this is the first report of AltMV in orchid cactus. It is not clear if AltMV alone causes symptoms in Epiphyllum spp., because two of the positive hybrids were asymptomatic, but the infected cactus may serve as a reservoir from which AltMV may spread to other hosts. We are currently characterizing the new cavemovirus detected in the hybrid Dragon Heart.

Phenolic Content Analysis And Evaluation of Antinociceptive, Antioxidant, Anti-Inflammatory Potential of Alternanthera Pungens Kunth

The present study evaluated the analgesic, anti-inflammatory and antioxidant activities of Alternanthera pungens kunth.The ethanolic extract of Alternanthera pungens (EAP) showed analgesic effects by exerting ameliorated reaction time 40.79% and 44.74% at a dose of 250 and 500 mg/kg,respectively, whereas standard was 41.78% by the hot plate test. Results of writhing inhibition were statistically significant (p <0.05) when compared to control. In addition to that, anti-inflammatory effects were also evaluated against denaturation of protein and the result was significant. Scavenging activity of EAP was 80.95% at the concentration of 800µg/mL. Moreover, HPLC-DAD analysis of EAP was also carried out to determine the presence of phenolic constituents & noted the presence of epicatechin,vanillin, p-coumaric acid etc. These studies inferred that EAP possesses analgesic, anti- inflammatory and antioxidant potential which might be due to presence of phytochemicals like flavonoids, tannins and phenolic compounds.
 Journal of Bangladesh Academy of Sciences, Vol. 42, No. 2, 129-136, 2018

Novel plant inducers of PXR-dependent cytochrome P450 3A4 expression in HepG2 cells

The cytochrome P450 3A4 (CYP3A4) is the most abundant CYP450 enzyme involved in the metabolism of endogenous products and xenobiotics, including prescription drugs and herbals. Modulation of hepatic CYP3A4 gene expression via nuclear receptors, like pregnane X receptor (PXR), is a major cause of adverse effects like drug-unresponsiveness and toxicity. In the present study, ethanol extracts of 58 medicinal plants, belonging to 27 families, were evaluated for potential activities in CYP3A4 induction in HepG2 cells by reporter gene assay. For PXR-mediated CYP3A4 induction, a 50 μg/ml concentration was used for all non-cytotoxic plants extracts. Rifampicin (10 μM) and DMSO (0.1%) were used as standard inducer and untreated (negative) control, respectively. The comparative fold-induction of CYP34A by the plant extracts in relation to the untreated control was determined. As a result, Dodonaea angustifolia (2.62 fold; P < 0.0001) was found to be the most promising inducer of CYP3A4, followed by Euphorbia tirucalli (1.95 fold; P = 0.0004), Alternanthera pungens (1.74 fold, P = 0.0035), and Ficus palmata (1.65 fold; P = 0.0097). Further phytochemical characterizations of the active plants are therefore, warranted.

Effect of Rolling on the Lateral Spread of Khakiweed (Alternanthera pungens Kunth)

The dark green color and abundant seed production of khakiweed (Alternanthera pungens Kunth) interfere with playability and aesthetic quality of home lawns, golf courses, and athletic fields. In 2009 and 2010, the effect of rolling on lateral spread of khakiweed was investigated in Lubbock, TX. Rolling treatments were conducted using a ride‐on roller that applied a static pressure of 58 kPa at a speed of 1.55 m s−1. Weekly rolling treatments were: nonrolled, low (4 passes × 3 events), moderate (8 passes × 3 events), and high (12 passes × 3 events). Khakiweed lateral plant diameters were recorded at trial initiation and every 2 wk over 12 wk. Statistical differences in khakiweed diameters were not observed until 10 wk after initial treatment (WAIT). Nonrolled plots exhibited 30.1 cm plant diameter, similar to low rolling (24.4 cm) but greater than moderate (23.3 cm) and high (20.4 cm) rolling 10 WAIT. A decrease in plant diameter was observed in response to high rolling (19.9 cm) 12 WAIT compared with nonrolled plots (28.8 cm). Although numerically less than the nonrolled check (28.8 cm), khakiweed plant diameters in response to low (23.5 cm) and moderate (23.1 cm) rolling were statistically similar. Although rolling treatments reduced khakiweed diameter compared with the nonrolled check, plants increased in size from initial trial diameters while hybrid bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt‐Davy] cover decreased over time in response to high rolling. Therefore, practices that reduce soil compaction may be important to increase bermudagrass competition with khakiweed.

Studies on Fungal Pathogens of Terrestrial Weeds of Kurukshetra

During extensive surveys conducted to search for naturally occurring fungal pathogens on various terrestrial weeds of Kurukshetra and its adjoining areas, dominance of Deuteromycetous fungi followed by obligate fungal pathogens were noticed. A total of 12 fungal pathogens were identified on 10 weeds belonging to 9 different families of Angiosperms on the basis of their morphological characteristics. Typical disease symptoms were produced by all non obligate pathogens on their respective hosts in vitro. Inoculated pathogens were isolated and were found similar to original isolates in cultural characteristics thus confirming the pathogenicity to their respective hosts and competing Koch's postulates. Leaf spots, powdery mildews, downy mildews, rust, and smut were the main diseases caused by the fungal pathogens on various terrestrial weeds of Kurukshetra. Symptoms of diseases caused by these pathogens and cultural characteristics of 12 fungal pathogens were recorded. Alternaria cassiae on Cassia occidentalis, Cercospora sp.-I on Ageratum conyzoides, Cercospora sp.-II on Alhagi camelorum, Cercospora sp.-III on Alternanthera pungens, Cercospora sp.-IV on Argemone mexicana, Cercosporsa sp.-XI on Peristrophe bicalyculata, Peronospora arborescens on Argemone mexicana, Puccinia sp. on Rumex dentatus, Ustilago cynodontis on Cynodan dactylon, Oidium sp.-I on Ageratum conyzoides, Oidium sp-IV on Sida rhombifolia and Peronospora sp. on Chenopodium album are new reports of occurrence of these pathogens from this region.

Studies on the Biology of Hypogeococcus pungens (sensu stricto) (Hemiptera: Pseudococcidae) in Argentina to Aid the Identification of the Mealybug Pest of Cactaceae in Puerto Rico.

Hypogeococcus pungens Granara de Willink, sensu stricto, is a serious pest of cacti in Puerto Rico threating many Caribbean islands. A classical biological control program for H. pungens was initiated for Puerto Rico in 2010 with a survey for natural enemies of H. pungens in its native range of Argentina. Biological differences were observed between populations of H. pungens sampled on Amaranthaceae and Cactaceae. Molecular studies suggested that H. pungens populations from different host plant families are likely a complex of species. Our objective was to study the biology of H. pungens sensu stricto on specimens collected in the same locality and host plant as the holotype [Tucumán Province, Argentina; Alternanthera pungens Kunth (Amaranthaceae)]. We were interested in the reproductive biology of females, longevity and survival of adults, the effect of temperature on the development, and nymph performance (survival and development) on five Cactaceae species. We found that H. pungens s.s. showed marked biological differences from the populations collected on Cactaceae and exported to Australia for the biological control of the cactus Harrisia spp. The main differences were the presence of deuterotoky parthenogenesis and the fact that H. pungens did not attack Cactaceae in the laboratory. Our results provide biological evidence that H. pungens is a species complex. We propose that the population introduced to Australia is neither Hypogeococcus festerianus Lizer y Trelles nor H. pungens, but an undescribed species with three circuli, and that the Hypogeococcus pest of cacti in Puerto Rico is not H. pungens.

Gene Expression Reaction Norms Unravel the Molecular and Cellular Processes Underpinning the Plastic Phenotypes of Alternanthera Philoxeroides in Contrasting Hydrological Conditions.

Alternanthera philoxeroides is an amphibious invasive weed that can colonize both aquatic and terrestrial habitats. Individuals growing in different habitats exhibit extensive phenotypic variation but little genetic differentiation. Little is known about the molecular basis underlying environment-induced phenotypic changes. Variation in transcript abundance in A. philoxeroides was characterized throughout the time-courses of pond and upland treatments using RNA-Sequencing. Seven thousand eight hundred and five genes demonstrated variable expression in response to different treatments, forming 11 transcriptionally coordinated gene groups. Functional enrichment analysis of plastically expressed genes revealed pathway changes in hormone-mediated signaling, osmotic adjustment, cell wall remodeling, and programmed cell death, providing a mechanistic understanding of the biological processes underlying the phenotypic changes in A. philoxeroides. Both transcriptional modulation of environmentally sensitive loci and environmentally dependent control of regulatory loci influenced the plastic responses to the environment. Phenotypic responses and gene expression patterns to contrasting hydrological conditions were compared between A. philoxeroides and its alien congener Alternanthera pungens. The terricolous A. pungens displayed limited phenotypic plasticity to different treatments. It was postulated based on gene expression comparison that the interspecific variation in plasticity between A. philoxeroides and A. pungens was not due to environmentally-mediated changes in hormone levels but to variations in the type and relative abundance of different signal transducers and receptors expressed in the target tissue.

Temperature Modulation of the Activity and Malate Inhibition of the Phosphoenolpyruvate Carboxylase from Leaves of Alternanthera pungens, Compared to that of Lycopersicom esculentum

Temperature caused marked modulation of phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) in leaf discs of Alternanthera pungens (C4 plant) as well as Lycopersicon esculentum (C3 species). The optimal incubation temperature for PEPC activity in A. pungens was 45 °C compared to 30 °C in L. esculentum. A. pungens lost nearly 61% of PEPC activity on exposure to a low temperature of 15 °C, compared to only about a 33% loss in the case of L. esculentum. The C4 enzyme was less sensitive to supra-optimal temperature and more sensitive to sub-optimal temperature than that of the C3 species. Further as the temperature was raised from 15 °C to 50 °C, there was a sharp decrease in malate sensitivity of PEPC. The extent of such a decrease in C4 plants was more than that in C3 species. Arrhenius plots that were constructed by plotting the activity of PEPC against the reciprocal of temperature in the absence or presence of malate exhibited abrupt changes or “break-points” at only one point of 17oC in A. pungens while at two points corresponding 17oC and 27oC in case of L. esculentum. The activation energy of PEPC from A. pungens was less compared to that of L. esculentum in the temperature range of 10 to 27oC. However, the activation energy of PEPC from A. pungens was less than that of L. esculentum above the temperature of 27oC. The activation energy increased by 2 to 4 fold at temperatures below 17oC, in case of both A. pungens and L. esculentum. Thus, our results show the activity and malate sensitivity of PEPC can be influenced in relation to high temperature tolerance of C4 plants, which can be physiologically significant.

Khakiweed (Alternanthera pungens Kunth) Growth Response to Mowing Height and Frequency

The effect of mowing regimens on lateral spread of khakiweed (Alternanthera pungens Kunth) was determined through field studies conducted over a 3-month period in Texas during 2009 and 2010. Treatments were selected to simulate mowing regimens common to intensively managed common bermudagrass [Cynodon dactylon (L.) Pers.] turf and included heights of 1.3 cm (three times/wk), 2.5 cm (two times/week), and 5.1 cm (two times/week). A non-mowed control was included for comparison. Differences in lateral spread of khakiweed among mowing regimens were apparent 4 weeks after initial treatment (WAIT). However, plant diameter increased for all mowing regimens over the course of the trial. Khakiweed plants subjected to the 1.3-cm mowing regimen did not increase in diameter from Week 2 through Week 12, whereas the other two mowing regimens exhibited steady increases in plant diameter over the same time period. By 12 WAIT, non-mowed control plots measured 80.8 cm in diameter, whereas those maintained at 1.3 cm measured 55.3 cm. Comparatively, plants subjected to the 2.5- and 5.1-cm mowing regimens measured 64.7 and 68.8 cm, respectively. Therefore, khakiweed infestations may be more prevalent in bermudagrass mowing heights commonly used for golf course roughs, athletic fields, and home lawns (2.5 cm or greater). However, the production of a thick taproot high in carbohydrate content may enable khakiweed to regenerate from frequent defoliation common to fairway mowing regimes (2.5 cm or less). Adjustments in mowing height may not be enough to effectively reduce khakiweed populations in bermudagrass turf.