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Solanum viarum, a perennial shrub, belongs to the family Solanaceae known for its therapeutic value worldwide. As a beneficial remedial plant, it is used for treating several disorders like dysentery, diabetes, inflammation, and respiratory disorders. Phytochemistry studies of this plant have shown the presence of steroidal glycoside alkaloids, including solasonine, solasodine, and solamargine. It also has flavonoids, saponins, minerals, and other substances. S. viarum extracts and compounds possess a variety of pharmacological effects, including antipyretic, antioxidant, antibacterial, insecticidal, analgesic, and anticancer activity. Most of the heavy metals accumulate in the aerial sections of the plant which is considered a potential phytoremediation, a highly effective method for the treatment of metal-polluted soils. We emphasize the forgoing outline of S. viarum, as well as its ethnomedicinal and ethnopharmacological applications, the chemistry of its secondary metabolites, and heavy metal toxicity. In addition to describing the antitumor activity of compounds and their mechanisms of action isolated from S. viarum, liabilities are also explained and illustrated, including any significant chemical or metabolic stability and toxicity risks. A comprehensive list of information was compiled from Science Direct, PubMed, Google Scholar, and Web of Science using different key phrases (traditional use, ethnomedicinal plants, western Himalaya, Himachal Pradesh, S viarum, and biological activity). According to the findings of this study, we hope that this review will inspire further studies along the drug discovery pathway of the chemicals extracted from the plant of S. viarum. Further, this review shows that ethnopharmacological information from ethnomedicinal plants can be a promising approach to drug discovery for cancer and diabetes. [ABSTRACT FROM AUTHOR]

Until recently, only a few plant viruses had been studied for use as biological control agents for weeds, but none had been developed into a registered bioherbicide. This position changed in 2014, when the US Environmental Protection Agency granted an unrestricted Section 3 registration for tobacco mild green mosaic virus (TMGMV) strain U2 as a herbicide active ingredient for a commercial bioherbicide (SolviNix LC). It is approved for the control of tropical soda apple (TSA, Solanum viarum), an invasive 'noxious weed' in the United States. TSA is a problematic weed in cattle pastures and natural areas in Florida. The TMGMV‐U2 product kills TSA consistently, completely, and within a few weeks after its application. It is part of the TSA integrated best management practice in Florida along with approved chemical herbicides and a classical biocontrol agent, Gratiana boliviana (Coleoptera: Chrysomelidae). TMGMV is nonpathogenic and nontoxic to humans, animals, and other fauna, environmentally safe, and as effective as chemical herbicides. Unlike the insect biocontrol agent, TMGMV kills and eliminates the weed from fields and helps recycle the dead biomass in the soil. Here the discovery, proof of concept, mode of action, risk analyses, application methods and tools, field testing, and development of the virus as the commercial product are reviewed. Also reviewed here are the data and scientific justifications advanced to answer the concerns raised about the use of the virus as a herbicide. The prospects for discovery and development of other plant‐virus‐based bioherbicides are discussed. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Simple Summary: Solanum viarum has been a widely invasive species. We aimed to understand the prevailing historical dispersal, ecological niche dynamics, and distribution patterns. The invasion history of S. viarum consisted of three phases: lagging (before 1980), dispersal (1980–2010), and equilibrium (2010–present). Ecological niches remained conservative. The potential geographic distribution of S. viarum will reach a maximum in the 2050s, SSP5–8.5, and in the future, it will migrate to higher latitudes. Global factors continue to increase this threat. The relevant quarantine authorities should take prevention and control measures. Solanum viarum has become extensively invasive owing to international trade, climate change, and land–use change. As it is classified as a quarantine weed by countries such as the U.S. and Mexico, it is critical to understand the prevailing historical dispersal, ecological niche dynamics, and distribution patterns. We reconstructed the historical invasion countries and analyzed the ecological niche shift of S. viarum. Using MaxEnt based on the conservativeness of ecological niches, we studied variations in the potential geographical distributions (PGDs) of S. viarum in ecosystems and variations in suitability probabilities along latitudinal gradients. The invasion history in six continents involved three phases: lag (before 1980), spread (1980–2010), and equilibrium (2010–present). The ecological niche remains conserved. The area of S. viarum PGDs had increased by 259 km2; the PGDs will expand to reach a maximum in the 2050s, SSP5–8.5. The PGDs of S. viarum will migrate to higher latitudes under the same future climate scenarios. The latitudes subject to high threats range from 20° to 30° in forest and cropland ecosystems, 15.5° to 27.5° (northern hemisphere) and 33.1° to 42.8° (southern hemisphere) in grassland ecosystems, and 20° to 35° in urban ecosystems. Global change has led to an increased threat of S. viarum at high latitudes. These findings provide a theoretical basis to monitor and control S. viarum. [ABSTRACT FROM AUTHOR]

ABSTRACTSpecies distribution modeling and niche dynamics of alien plants can aid in understanding the existing and future invasion potential in the wake of climate change. We describe the niche dynamics of S. viarum Dunal, and report on its present and predicted future distribution in Pakistan under scenarios of climate change. The results revealed that S. viarum had an extensive range of prospective distribution zones in Pakistan, with Central Punjab, Eastern Khyber Pakhtunkhwa, and Southern Balochistan being the most suitable. According to ROC curve data, the MaxEnt model has a great prediction precision and credible outcomes. The most important variables influencing S. viarum latent distribution may be precipitation and temperature. The current potential area of S. viarum is approximately 105,750 km2 (12%). Under climate change regimes, the highly suitable area for S. viarum increases by 2–9% under two Representative Concentration Pathways (RCP 4.5 and RCP 8.5). The outcomes of this study could help to develop control of regional invasions and climate change approaches in Pakistan. More importantly, the findings of niche dynamics in native and invaded S. viarum areas contribute to a better understanding of the nature of niche modifications in invasive species and the potential for invasion under climate change.

Solanum viarum serves as a raw material for the steroidal drug industry due to its alkaloid and glycoalkaloid content. Elicitation is well-known for measuring the increase in the yield of bioactive compounds in in vitro cultures. The current study was performed for the accumulation of metabolites viz. solasodine, solanidine, and α-solanine in S. viarum culture using microbial-based elicitors added in 1%, 3%, 5%, and 7% on 25th and 35th day of culture period and harvested on 45th and 50th days of culture cycle. The treatment of 3% Trichoderma reesei and Bacillus tequilensis culture filtrate (CF) significantly increased biomass, alkaloids/glycoalkaloid content, and yield in S. viarum. T. reesei was found to be the best treatment for enhanced growth (GI = 11.65) and glycoalkaloid yield (2.54 mg DW plant−1) after the 50th day of the culture cycle when added on the 25th day. The abundance of gene transcripts involved in the biosynthesis of alkaloids/glycoalkaloids, revealed by quantitative real-time PCR expression analysis correlates with the accumulation of their respective metabolites in elicited plants. Biochemical analysis shows that elicited plants inhibited oxidative damage caused by reactive oxygen species by activating enzymes (superoxide dismutase and ascorbate peroxidase) as well as non-enzymatic antioxidant mechanisms (alkaloids, total phenols, total flavonoids, carotenoids, and proline). The findings of this study clearly demonstrate that the application of T. reesei and B. tequilensis CF at a specific dose and time significantly improve biomass as well as upregulates the metabolite biosynthetic pathway in an important medicinal plant- S. viarum. Key points: • Biotic elicitors stimulated the alkaloids/glycoalkaloid content in S. viarum plant cultures. • T. reesei was found to be most efficient for enhancing the growth and alkaloids content. • Elicited plants activate ROS based-defense mechanism to overcome oxidative damage. [ABSTRACT FROM AUTHOR]

Solanum viarum has become extensively invasive owing to international trade, climate change, and land–use change. As it is classified as a quarantine weed by countries such as the U.S. and Mexico, it is critical to understand the prevailing historical dispersal, ecological niche dynamics, and distribution patterns. We reconstructed the historical invasion countries and analyzed the ecological niche shift of S. viarum. Using MaxEnt based on the conservativeness of ecological niches, we studied variations in the potential geographical distributions (PGDs) of S. viarum in ecosystems and variations in suitability probabilities along latitudinal gradients. The invasion history in six continents involved three phases: lag (before 1980), spread (1980–2010), and equilibrium (2010–present). The ecological niche remains conserved. The area of S. viarum PGDs had increased by 259 km2; the PGDs will expand to reach a maximum in the 2050s, SSP5–8.5. The PGDs of S. viarum will migrate to higher latitudes under the same future climate scenarios. The latitudes subject to high threats range from 20° to 30° in forest and cropland ecosystems, 15.5° to 27.5° (northern hemisphere) and 33.1° to 42.8° (southern hemisphere) in grassland ecosystems, and 20° to 35° in urban ecosystems. Global change has led to an increased threat of S. viarum at high latitudes. These findings provide a theoretical basis to monitor and control S. viarum.

Growth and production kinetics of three important glycoalkaloids viz. α-solanine, solanidine, and solasodine in two contrasting prickly and prickleless plants of Solanum viarum Dunal were evaluated under in vitro conditions. The prickleless plants showed improved accumulation of total glycoalkaloid content [7.11 and 6.85 mg g−1 dry weight (DW)] and growth (GI = 11.08 and 19.26) after 45 and 50 days of culture cycle, respectively. For higher biomass (91.18 g l−1) as well as glycoalkaloid (52.56 mg l−1) recovery, the prickleless plants served as highly profitable platform. All the three studied glycoalkaloids were identified and quantified by mass spectrometry and HPLC. All the three studied glycoalkaloids accumulated in age-dependent manner. The presence of two constituents, i.e., solasodine and solanidine mainly contributed for higher accumulation of total glycoalkaloid content in the prickleless plants. However, the synthesis of α-solanine was highly age specific and could be detected after 4 to 5 weeks of culture cycle in both prickle containing as well as prickleless plants of S. viarum. The higher accumulation of glycoalkaloids in prickleless plants was also supported with the expression analysis of six key pathway enzymes viz. mevalonate kinase (MVK), 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMGR), farnesyl diphosphate synthase (FPS), UDP-galactose/solanidine galactosyltransferase (SGT1), UDP-glucose/solanidine glucosyltransferase (SGT2), and cytochrome P450 monooxygenase (CYP). The results indicated that the plants harvested after 45 and 50 days of culture cycle accumulated maximum bioactive in-demand glycoalkaloids in the prickly and prickleless plants of S. viarum Dunal, respectively. [ABSTRACT FROM AUTHOR]

Solanum viarum has been proposed as a potential dead-end trap crop for the management of Helicoverpa armigera because of its unsuitability for larval growth and survival despite being overwhelmingly preferred for oviposition. This study delved into the different S. viarum accessions for ovipositional preference and non-suitability for larval growth and survival of H. armigera. Besides, foliage trichomes, acylsugars, and phenolic content of S. viarum plants were assessed and compared with tomato. Since there is no significant variation in the ovipositional preference and larval performance of H. armigera, our result revealed that all those evaluated accessions of S. viarum have the potential to be used as a dead-end trap crop for the management of H. armigera. However, significant variation among the S. viarum accessions in terms of H. armigera oviposition was also evident in a no-choice experiment. Because of high-density glandular trichomes, acylsugars, and phenolic content, S. viarum significantly impaired H. armigera larval growth and survival compared to the tomato. Hence, our study elucidated that the S. viarum plant fits with the criteria for dead-end trap crop, and has the potential as a dead-end trap crop for the H. armigera, which needs to be tested under large, open-field conditions.

Objective: The aim of the study was evaluate the tannin content, antioxidant activity and the lethality of unripe fruits extract of Solanum viarum Dunal (Solanaceae) against brine shrimps. Methods: The tested samples for tannins content were water, ethanol:water (1:3) and acetone:water (1:3) extract. The unripe fruits powder of S. viarum was used to extraction in a Soxhlet apparatus for 2 hr. Cytotoxicity was screened using Brine Shrimp Lethality Test and aqueous extract. Results: The results demonstrated that the yield of tannins for the acetone:water extraction was substantially higher than that typical yields obtained by ethanol:water or water extraction [31.10% for Total Solids (%), 14.99% for Stiasny's Index (%), 3.99% for Condensed Tannins in the Extract (%) and 1.09% for Condensed Tannins in the Unripe Fruits (%). The antioxidant activity was 61.12±12.42% compared to ascorbic acid (100%) and polyphenol concentration was 39.33±4.45 mg of tannic acid/g of extract obtained from the tannic acid calibration curve y = 0.0128x - 0.0015 (R² = 0.9988). Flavonoid concentration was 89.36 ± 11.6 mg of quercetin/g of extract obtained by quercetin calibration curve y=0.0153x+0.0109, R²=0.9827. The results demonstrated that the positive control (potassium dichromate) hatching success was significantly higher than the S. viarum extract (P<0.05). LC50 was 66.01 μg/ml for the water extract of unripe fruit of S. viarum and in accord to Clarkson's toxicity criterion, LC50< 100 μg/mL are considered highly toxic for aqueous extract. Conclusion: The unripe fruit extract of S. viarum demonstrated low percentage in phenolic content, but significant antioxidant activity and phenolic and flavonoid concentrations. S. viarum unripe fruits extract is toxic to Artemia salina. [ABSTRACT FROM AUTHOR]

Tropical soda apple ( Solanum viarum Dunal) (Solanaceae) is a small shrub native to South America that is invasive in pastures and conservation areas across Florida. Dense patches of tropical soda apple not only reduce cattle stocking rates and limit their movement, but also serve as reservoirs for pests of solanaceous crops. A classical biological control program was initiated in 1994 with exploration for natural enemies of tropical soda apple in Argentina, Brazil, and Paraguay. Host specificity tests conducted under laboratory and field conditions demonstrated that the leaf feeding beetle Gratiana boliviana Dunal (Coleoptera: Chrysomelidae) was a specialist herbivore that completes development only on the target weed. After obtaining appropriate permits, field releases of G. boliviana were initiated in Florida in May of 2003. Larvae and adults of G. boliviana feed on tropical soda apple leaves and may completely defoliate their host plants, resulting in reduced growth and fruit production. Mass rearing facilities for the beetle were established in northern, central and southern Florida, and adults were either hand-carried or transported to release sites by overnight courier. From 2003 to 2011, a total of 250,723 beetles were released and they became established throughout Florida, however, their impact is more noticeable in regions below latitude 29 °N. Reductions of tropical soda apple densities caused by damage by the beetle were visible 2-3 yr after initial release, or in some cases, within a few months. Various methods of technology transfer were used to inform the public, land owners, funding agencies and scientists about the biological control program, including articles in trade magazines, extension publications, websites, videos, field days and scientific publications. The project was successful because of the coordinated efforts of personnel from federal, state and county agencies. [ABSTRACT FROM AUTHOR]

The medicinal plant, Solanum viarum Dunal includes a number of compounds with important pharmacological effects. The effect of temperature (heat and cold) stress on growth, secondary metabolite levels and defense mechanism in two genotypes (prickled and prickleless) of S. viarum was evaluated. The two thermal regimes (4 °C for cold and 35 °C for heat stress) were found to be the most optimum for the accumulation of metabolites (steroidal alkaloids and glycoalkaloids, phenolic acids as well as flavonoids). Prickleless genotype showed 4.08 and 1.51 fold higher total alkaloids/glycoalkaloid content at 35 °C and 4 °C temperatures respectively, in comparison with prickled plants. Prickleless plants also registered 2.03 and 2.28 higher fresh and dry biomass accumulation respectively, under cold stress over the control plants. The accretion of phenolic and flavonoid compounds under heat and cold stress is mainly contributed by gallic and ferulic acid in both the genotypes. The quantitative real-time PCR expression analysis showed the abundance of gene transcript involve in the biosynthesis of alkaloids/glycoalkaloid and phenolics/flavonoids that corroborates with the accumulation of their respective metabolites in prickleless plants under temperature stress. Results revealed that the prickleless plants inhibiting the reactive oxygen species (ROS) mediated oxidative damage by activating the enzymatic (superoxide dismutase, peroxidase, catalase and ascorbate peroxidase) and non-enzymatic (alkaloids, phenols, flavonoids, carotenoids and proline) antioxidants mechanism that confirms its efficiency to tolerate thermal stress under both the thermal regimes. The overall result showed that the prickleless genotype served as a better accumulator of biomass, secondary metabolites with an improved antioxidative mechanism in comparison to prickled genotype. Our findings suggest that thermal stress responses differ significantly between genotypes, emphasizing the necessity of maintaining genotypic diversity in adaptive evolution as in the context of global warming and climate change. The present study also opens the possibility of exploiting improved prickleless genotype of S. viarum as a potential system that can be cultivated under different temperature stress conditions to attain the phytopharmaceutical benefits. • Temperature stress tolerance in two genotypes of Solanum viarum was investigated. • Two thermal regimes 35 °C and 4 °C supports higher secondary metabolite synthesis. • Growth, metabolite and antioxidant response to temperature is genotype-dependent. • A positive correlation between biosynthetic pathway genes and metabolite accretion. • In prickleless genotype, higher metabolite accretion led to improved defense system. [ABSTRACT FROM AUTHOR]

Tropical soda apple (Solarium viarum Dunal) is a major exotic weed in pastures and conservation areas in subtropical regions. Anthonomus tenebrosus Boheman (Coleoptera: Curculionidae) was found feeding on the flowers of tropical soda apple in southern Brazil and was considered a potential biological control agent. The objectives of this study were to examine the life history and host specificity of A. tenebrosus. The development from egg to adult was measured at eight constant temperatures in growth chambers. The presence of reproductive diapause was measured by using a two-way factorial design with three temperatures (20, 22.5, and 25°C) and two photoperiods (14:10 and 10:14 [L:D] h). Temperature influenced the developmental time from egg to adult of A. tenebrosus, which ranged from 49.6 d at 16°C to 13.6 d at 28°C. The longevity of males ranged from 64 to 190 d, whereas females lived from 44 to 204 d. When exposed to 10:14 (L:D) h and 20°C, 35% of females entered reproductive diapause. The fundamental host range of A. tenebrosus--based on several life-history aspects, including adult longevity, oogenesis, and oviposition--and immature development of A. tenebrosus were studied. Under no-choice conditions, «80% of adults survived for 30 d on several Solanum melongena L. varieties, Solanum capsicoides, S. viarum, and Solanum carolinense L. A. tenebrosus completed development from egg to adult on a number of S. melongena varieties, the native plant S. carolinense, and the exotic plants S. capsicoides All., S. viarum, and Solanum tampicense Dunal. Under paired-choice conditions, adult feeding occurred on all species, whereas oviposition occurred only on S. viarum, S. capsicoides, and S. carolinense. Because of the nontarget attack to S. melongena and a native plant, A. tenebrosus should not be considered for release as a biological control agent of tropical soda apple in the United States. [ABSTRACT FROM AUTHOR]

Rising atmospheric CO2 levels could have drastic effects on the performance of invasive weeds and their insect herbivores. Despite the importance of biological control as an effective management tool for environmental weeds, there have been few studies on the potential impact of climate change on the future efficacy of biological control. The objective of the present study was to evaluate the effect of elevated CO2 on the performance of tropical soda apple Solanum viarum (Solanaceae) and its biological control agent Gratiana boliviana (Coleoptera: Chrysomelidae). We established three levels of CO2 in environmental growth chambers: ambient (400 ppm), medium (580 ppm) and high (780 ppm). Plants growing at the high level had greater biomass compared to those growing at the ambient and medium levels of CO2. Leaf water content and the amount of leaf nitrogen were reduced at high compared to ambient or medium CO2 levels. G. boliviana immature survival and developmental time were negatively affected at high CO2 but not at medium or ambient levels. Adults were lighter and smaller when reared at the high CO2 level compared to ambient and medium treatments, while adult fecundity was higher at the medium CO2 level. Leaf area consumed by fifth instars was lower when feeding on plants grown at the high CO2 level either inside a Petri dish or on potted plants. These results suggest that beetle performance may be diminished under future climate. However, further studies should incorporate other factors such as temperature and precipitation as well as the evolutionary potential of herbivores and plants to adapt to a changing climate. [ABSTRACT FROM AUTHOR]

Abstract: Tropical soda apple (TSA), Solanum viarum Dunal (Solanaceae), has invaded many pastures and natural areas in Florida. The biological control agent Gratiana boliviana Spaeth (Coleoptera:Chrysomelidae) is providing adequate control of TSA stands in South and Central Florida. However, poor or no establishment of this agent has occurred in northern Florida. The goal of this study was to examine the mortality factors that influence the population dynamics of G. boliviana in Florida. Horizontal life tables were constructed by following cohorts of individuals in the laboratory and inside closed and open cages at field sites in Central and North Florida. Fertility life table parameters were estimated using laboratory and field data. In addition, as part of a vertical life table analysis, TSA plants were sampled every two weeks in pastures in Central Florida, and counts of all G. boliviana and other herbivores and predators were recorded. Survival to adulthood was similar between Central and North Florida (open cages: 12–19%). Intrinsic mortality (laboratory data) and biotic factors (predation) together accounted for 75% of the mortality of immature stages. Survival of beetles in a natural population determined from vertical life tables was 5%. A complex of three mirid species (Engytatus modesta Distant, Tupiocoris notatus Distant, and Macrolophus sp.) were the most abundant predators found in the field, and are known to feed on G. boliviana eggs and larvae. Positive growth rates (r m =0.3) during the summer and early fall allow the beetle population to increase and provide suppression of TSA in Central Florida. [Copyright &y& Elsevier]

The leaf feeding beetle Gratiana boliviana Spaeth has been released since 2003 in the southeastern United States for biological control of tropical soda apple, Solanum viarum Dunal. In Florida, G. boliviana can be found on tropical soda apple growing in open pastures as well as in shady wooded areas. The objectives of this study were to determine the effect of light intensity on the performance of tropical soda apple and G. boliviana under greenhouse conditions, and to determine the abundance and mortality of G. boliviana in open and shaded habitats. Leaves growing in the shade were less tough, had higher water and nitrogen content, lower soluble sugars, and less dense and smaller glandular trichomes compared with leaves growing in the open. Plants grew slightly taller and wider under shaded conditions but total biomass was significantly reduced compared with plants grown in the open. In the greenhouse, G. boliviana had higher immature survival, greater folivory, larger adult size, and higher fecundity when reared on shaded plants compared with open plants. Sampling of field populations revealed that the overall abundance of G. boliviana was lower but leaf feeding damage was higher in shaded habitats compared with the open habitats. The percentage of eggs surviving to adult was greater in shaded compared with open habitats. The abundance of predators was higher in the open pasture and was positively correlated with the abundance of G. boliviana. These results indicate that not only plant quality but also habitat structure are important to the performance of weed biological control agents. [ABSTRACT FROM AUTHOR]

The South American leaf-feeding beetle Gratiana boliviana Spaeth (Coleoptera: Chrysomelidae) has been released since 2003 in the southeastern United States to control the invasive weed tropical soda apple, Solanum viarum Dunal (Solanaceae). Successful establishment of a biological control agent in temperate and subtropical regions depends on several life-history adaptations, including winter diapause. The timing of diapause allows the syncronization of insect herbivores with the phenology of plants, and field observations in Florida suggested that G. boliviana overwinters as an adult in diapause. The objectives of this study were to describe the diapause of G. boliviana and determine the effect of temperature and photoperiod on diapause induction. Compared with non-diapause adults, diapausing adults were yellow rather than green, had hypertrophied fat bodies, contained little food in the digestive tract, showed negligible ovarian development, and minimal movement of the hind wings when the beetles were placed on their dorsal sides. Although all nondiapause females laid eggs during a 30-d period, only five of 76 diapausing females laid eggs and this occurred only during the first 15 d of the treatment period. Consistent with morphological indicators of diapause, the respiration rate was 2.3 times lower and fat content was 2-3 times greater in diapausing adults compared with nondiapause adults. In a laboratory study, the critical daylength for diapause induction was found to be 12 h:28 min. [ABSTRACT FROM AUTHOR]

Multiple-choice and no-choice tests were conducted at the Florida Department of Agriculture quarantine facility to determine the host specificity of the South American flower bud weevil, Anthonomus tenebrosus Boheman, intended for biological control of the exotic weed tropical soda apple (TSA), Solanum viarum Dunal in Florida, USA. Ninety-one plant species in 21 families were included in multiple-choice feeding and oviposition experiments, including the target weed and the 6 major cultivated Solanaceae: bell pepper ( Capsicum annuum L.), chili pepper (C. frutescens L.), tomato (Lycopersicon esculentum Mill.), tobacco (Nicotiana tabacum L.), eggplant (Solanum melongena L.), and potato (Solanum tuberosum L.). Plant bouquets with flower-buds of 8 to 10 randomly selected plant species, always including TSA ( S. viarum ) were exposed to 10-20 A. tenebrosus adults for 1 to 2 weeks. Oviposition and feeding were observed twice a week. No-choice host-specificity tests were also conducted with A. tenebrosus adults using potted flowering plants. Ten adults were exposed to 29 plant species individually tested for 1 to 2 weeks. Plant species in each test were replicated 3 or 4 times. All tests showed that A. tenebrosus fed and laid eggs only on the target weed. No eggs were deposited on any of the other of the 91 plant species tested. Host-specificity tests indicated that a host range expansion of A. tenebrosus to include any of the crops, and native Solanaceae, and non-solanaceous plants tested is highly unlikely. A petition for field release in the USA was submitted to the Technical Advisory Group for Biological Control Agents of Weeds (TAG) in Oct 2007 . [ABSTRACT FROM AUTHOR]

Gratiana boliviana Spaeth (Coleoptera: Chrysomelidae), the first biocontrol agent introduced against tropical soda apple, Solanum viarum Dunal (Solanaceae), was released in Florida in the summer 2003. Post-release evaluations have focused on insect population changes and the impact of insect feeding damage on the plant defoliation and fruit production of the target weed. Gratiana boliviana quickly established in the release sites, and dispersed causing extensive defoliations to tropical soda apple plants and significant reduction of fruit production. Plant defoliation during the first growing season was directly associated with the increase in number of beetles observed on the tropical soda apple plants. Beetles showed a dispersal ability from the release sites of 1.6 km per year. Two years after the beetle release, most of the tropical soda apple plants at the 3-ha release site in Polk County and at the release site in Okeechobee County, Florida have been replaced by other plant species, resulting in improved pastures. No negative non-target effects have been observed, even in plants closely related, such as the non-natives Solanum capsicoides Allioni and Solanum torvum Swartz that were growing in the proximity or mixed with tropical soda apple in the monitored sites. [ABSTRACT FROM AUTHOR]

Multiple-choice and no-choice tests were conducted at the Department of Agriculture, Division of Plant Industry Quarantine facility in Gainesville, FL to determine the specificity of the Brazilian leaf-beetle Gratiana graminea Klug, a candidate for biological control of Solanum viarum, tropical soda apple. One hundred fifteen plant species in 32 families were included in the feeding-oviposition multiple-choice tests including the target weed and the 5 major cultivated Solanaceae Capsicum annuum L., Lycopersicon sculentum Mill., Nicotiana tabacum L., Solanum melongena L., and Solanum tuberosum L. Eight to 12 plant species, including always the main target weed, growing in 1-gallon pots were simultaneously exposed to 20 G. graminea adults (10 males and 10 females that most of the time had recently emerged from pupae) in an aluminum cage (60 × 60 × 60 cm). At the beginning of each test the insects were placed at the bottom center of each cage to allow them to orient by themselves to the tested plants. Plant species in each test were replicated 3-4 times (one replication of tested plants in each separate cage). Plants tested were exposed to G. graminea adults from 3-6 weeks. Observation of oviposition and feeding were made during almost all the weekdays. No-choice host specificity tests were conducted with G. graminea adults on potted plants in cages made of clear-plastic cylinders and with G. graminea larvae placed on cluster of leaves of each individual plant tested. Ten G. graminea adults were exposed to 29 plant species individually tested during 3 to 5 weeks, and 10 neonate larvae were exposed to 31 plant species. Plant species in each test were replicated 3-4 times. Results indicated that G. graminea fed and developed only on the target weed. The tests indicated that a host range expansion of G. graminea to any of the major cultivated Solanaceae species is highly unlikely. A petition for field release in Florida was submitted to the Technical Advisory Group for Biological Control Agents of Weeds (TAG) in Sep 2008. [ABSTRACT FROM AUTHOR]

Tropical soda apple is a perennial invasive weed species that has become a serious problem in both agricultural and natural areas of the southeastern United States. A field survey was conducted at a ranch in Madison County, Florida, to assess the effect of sun and shade conditions on the abundance and feeding activity of Gratiana boliviana Spaeth (Coleoptera: Chrysomelidae) on tropical soda apple. The results revealed that beetle abundance and their feeding damage were greater on plants growing in full sun exposure than on plants growing in shaded habitat. [ABSTRACT FROM AUTHOR]

The present study was designed to evaluate the antibacterial activities and phytochemical profile of extracts from leaves of Solanum viarum. The in vitro antimicrobial activity was performed by agar disc diffusion method against bacteria, viz., Staphylococcus aureus, Klebisella pneumoniae, Escherischia coli, Pseudomonas aeruginosa and fungi, Aspergillus niger, Penicillium sp., Candida albicans. The n-butanol, methanol and aqueous extracts of fresh leaves of S. viarum showed maximum activity against P. aeurginosa, followed by S. aureus and E. coli, among the organisms observed. Solanum viarum was observed to have antimicrobial activity and can be used for medicinal purposes. [ABSTRACT FROM AUTHOR]

Abstract: Tropical soda apple (Solanum viarum Dunal (Solanaceae) is a South American invasive plant of rangelands, pastures and natural areas in Florida. A chrysomelid beetle from South America, Gratiana boliviana Spaeth, has been released at >300 locations in Florida for biological control of tropical soda apple since 2003. Tropical soda apple is a host of several plant viruses, including the newly described tropical soda apple mosaic virus (TSAMV). We investigated the influence of TSAMV infection of tropical soda apple plants on developmental time, leaf tissue consumption, longevity, fecundity, and feeding preference of G. boliviana, and also tested transmission of the virus by the beetle. Developmental time was approximately 10% slower, and adults consumed only about 50% as much leaf tissue, for beetles fed on infected plants compared to uninfected plants. Longevity did not differ between females reared on infected and uninfected plants, but females fed on uninfected plants produced 71% more eggs than those fed on infected plants. Adult G. boliviana preferentially fed on uninfected plants when given a choice. There was no evidence of TSAMV transmission by G. boliviana. The potential impacts of TSAMV infection on the effectiveness of G. boliviana as a biological control agent are discussed. [Copyright &y& Elsevier]

Erwinia carotovora subsp. carotovora, a plant pathogenic bacterium, was combined with a one-quarter rate of two herbicides, triclopyr (3,5,6-trichloro-2-pyridinyloxy acetic acid and dicamba (3,6-dichloro-o-anisic acid), to control tropical soda apple (TSA) (Solanum viarum). E. c. subsp. carotovora inoculated at the growing point of TSA plants was consistently recovered from the stem and roots from 5 to 35 days after inoculation indicating its persistence and spread in host tissue. Plants in greenhouse studies were inoculated with a suspension of E c. subsp. carotovora and Silwet L-77 (1.25%) alone or combined with reduced rates (25%) of triclopyr or dicamba at 0.28 kg ai/ha, or each herbicide alone. Control plants were inoculated with water and Silwet L-77. At 72 and 112 days after treatment (DAT), the percentage of leaf area injured (LAI) per plant was estimated using a scale of 0–100, where 0=no injury and 100%=entire plant necrotic. Injury to plants was necrosis and wilting of leaf, petiole, and stems. Injured plants regenerated from root buds, and plants that regenerated were rated at 0% LAI (no visible injury). Plants inoculated with E. c. subsp. carotovora and Silwet L-77 or water and Silwet L-77 treatments had 0% LAI. Plants treated with E. c. subsp. carotovora and triclopyr or dicamba had 82.5% and 42% LAI at 72 DAT and did not regenerate by 112 DAT. Plants treated with triclopyr had 82.0% LAI and dicamba-treated plants had 36.5% LAI at 72 DAT. Twenty percent and 32% of the plants treated with triclopyr and dicamba regenerated by 112 DAT, and had 62% and 4.5% LAI, respectively. Plants treated with dicamba and the bacterium had significantly higher LAI (82.5%) compared to those treated with dicamba (4.5%) at 112 DAT. In field trials, plants treated with the bacterium and Silwet L-77 combined with triclopyr or dicamba had 87.5% and 50% LAI at 72 DAT, respectively, and no plants regenerated. Plants treated with triclopyr had 96% LAI at 72 DAT, and 12% of these plants regenerated. At 112 DAT, the LAI on plants was 84%. Plants treated with dicamba had 47.5% LAI, and 15% of the plants regenerated. At 112 DAT, the LAI was 32.5%, which was significantly lower than the LAI on the dicamba-bacterium treated plants. The combination of E. c. subsp. carotovora and dicamba caused greater plant injury and than the herbicide alone and completely prevented the regeneration of plants. [Copyright &y& Elsevier]

• Prickled and prickleless plants were profiled for steroidal alkaloids and phenolics under in vitro and field conditions. • Prickleless plants showed higher growth and metabolite contents in comparison to prickled plant. • The accumulation of metabolites in a tissue-specific manner corroborates with the expression of biosynthetic pathway genes. • The leaves and roots of prickleless plants can be harvested for pharmaceutical benefit. Solanum viarum Dunal, is an important medicinal plant widely used as a source of raw material for the steroidal drug industry. Out of various steroidal precursors, solasodine, an analogue of diosgenin is the most important source of raw material for the synthesis of steroidal drugs. In the present study, growth and phytochemical variations in different tissue (leaves, stem, roots, and berries) of two contrasting genotypes, prickled and prickleless Solanum viarum were evaluated under in vitro and field conditions. Significant variation in growth, yield and contents of glycoalkaloids, phenolics, and flavonoids were evident between two genotypes under in vitro and field conditions. Prickleless genotypes showed improved growth parameters both under in vitro and field conditions, that helps in contributing to higher yield over prickled plants. Tissue-specific chemical analysis revealed that the leaves and roots of prickleless plants serve as a better repertoire for bioactive phytomolecules. The vegetative parts of in vitro grown 50 days old prickleless plants showed comparable/higher metabolite content than 7–8 month old field-grown plants. Hence it can be used as an alternative production platform for further upscaling, elicitation, and precursor feeding targets that enhances its commercial utility. The expression analysis of seven genes involved in the regulation of important metabolite biosynthesis in both prickled and prickleless genotype of Solanum viarum was also examined. The diverse metabolite profiles are correlated with variations in gene expression profiles. This study provides information about the key metabolites and its biosynthetic pathway genes, which could be useful for the selection of an improved prickleless genotype ("Nishkantak") of Solanum viarum. [ABSTRACT FROM AUTHOR]

Simple Summary: The tomato fruitworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), is a destructive polyphagous insect pest of tomatoes and its control largely depends on chemical pesticides. However, indiscriminate use of chemical pesticides has resulted in the development of resistance and posed serious environmental problems. Alternatively, in search of environmentally friendly pest management techniques, the use of trap crops has recently gained more attention. In this study, we compared different accessions of S. viarum to investigate which of them have the highest potential as a dead-end trap crop for H. armigera. Results from the laboratory experiment showed a significant variation among the S. viarum accessions in terms of H. armigera oviposition, and exhibited a higher level of resistance against H. armigera larvae compared to the tomato plants. Under the semi-field condition, trap cropping of S. viarum significantly reduces the total egg-laying of H. armigera on tomato. This study provides important information about the abilities of S. viarum plants to influence the life parameter of H. armigera and highlighted the possibilities to use S. viarum as a dead-end trap crop for the management of H. armigera. However, the efficacy of S. viarum needs to be tested under large, open-field conditions. Solanum viarum has been proposed as a potential dead-end trap crop for the management of Helicoverpa armigera because of its unsuitability for larval growth and survival despite being overwhelmingly preferred for oviposition. This study delved into the different S. viarum accessions for ovipositional preference and non-suitability for larval growth and survival of H. armigera. Besides, foliage trichomes, acylsugars, and phenolic content of S. viarum plants were assessed and compared with tomato. Since there is no significant variation in the ovipositional preference and larval performance of H. armigera, our result revealed that all those evaluated accessions of S. viarum have the potential to be used as a dead-end trap crop for the management of H. armigera. However, significant variation among the S. viarum accessions in terms of H. armigera oviposition was also evident in a no-choice experiment. Because of high-density glandular trichomes, acylsugars, and phenolic content, S. viarum significantly impaired H. armigera larval growth and survival compared to the tomato. Hence, our study elucidated that the S. viarum plant fits with the criteria for dead-end trap crop, and has the potential as a dead-end trap crop for the H. armigera, which needs to be tested under large, open-field conditions. [ABSTRACT FROM AUTHOR]