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In the Caribbean Basin, malvaceous weeds commonly show striking golden/yellow mosaic symptoms. Leaf samples from Malachra sp. and Abutilon sp. plants with these symptoms were collected in Hispaniola from 2014 to 2020. PCR tests with degenerate primers revealed that all samples were infected with a bipartite begomovirus, and sequence analyses showed that Malachra sp. plants were infected with tobacco leaf curl Cuba virus (TbLCuCV), whereas the Abutilon sp. plants were infected with a new bipartite begomovirus, tentatively named Abutilon golden yellow mosaic virus (AbGYMV). Phylogenetic analyses showed that TbLCuCV and AbGYMV are distinct but closely related species, which are most closely related to bipartite begomoviruses infecting weeds in the Caribbean Basin. Infectious cloned DNA-A and DNA-B components were used to fulfilled Koch’s postulates for these diseases of Malachra sp. and Abutilon sp. In host range studies, TbLCuCV also induced severe symptoms in Nicotiana benthamiana, tobacco and common bean plants; whereas AbGYMV induced few or no symptoms in plants of these species. Pseudorecombinants generated with the infectious clones of these viruses were highly infectious and induced severe symptoms in N. benthamiana and Malachra sp., and both viruses coinfected Malachra sp., and possibly facilitating virus evolution via recombination and pseudorecombination. Together, our results suggest that TbLCuCV primarily infects Malachra sp. in the Caribbean Basin, and occasionally spills over to infect and cause disease in crops; whereas AbGYMV is well-adapted to an Abutilon sp. in the Dominican Republic and has not been reported infecting crops.

Based on our previous work on the structural modification of the lead compound I , three series of novel fluorine-containing phosphonates derivatives ( II, III and IV) were designed and synthesized. Their post-emergence herbicidal activities against some species of weeds were evaluated in a green house. The compounds II were synthesized by introducing of two methylene into the structure I . Compared with the commercial herbicidal clacyfos, compounds II showed moderate herbicidal activity with 60–85% inhibition effect against chingma abutilon ( Abutilon theophrasti ), common amaranth ( Amaranthus retroflexus ) and white eclipta ( Eclipta prostrate ) at a rate of 150 g ai/ha. The compounds III were designed by introducing open-chain phosphonates, which displayed notable herbicidal activity. Especially, the compounds III-1 – III-4 , III - 6 , III - 8 , III - 11 and III - 12 exhibited significant herbicidal activity (80–100%) comparing to the clacyfos against all tested broadleaf weeds, while compounds IV with five carbon atoms in the carboxylic acid chain were inactive against all of the tested weeds. Structure-activity relationship analyses indicated that the length of the carbon chain had a great effect on the herbicidal activity. Furthermore, a broad spectrum test confirmed that compounds III - 4 and III - 8 were comparable with glyphosate against all of the tested weeds at a rate of 75 g ai/ha.

The supply of soil resources is critical for the establishment and long-term competitive success of a plant species. Although there is considerable research on the effects of water supply on crop growth and productivity, there is little published research on the comparative response of crops and weeds to limiting soil water supply. The objective of this research was to determine the growth and transpiration efficiency of corn and velvetleaf at three levels of water supply. One corn or velvetleaf plant was grown in a large pot lined with plastic bags. When seedlings reached 10 cm, bags were sealed around the base of the plant, so the only water loss was from transpiration. Daily transpiration was measured by weighing the pots at the same time each day. The experiment was conducted in the fall of 2007 and in the spring of 2008. Four replicates of each species–water treatment were harvested periodically to determine biomass accumulation and leaf area. The relationship between cumulative aboveground biomass and water transpired was described using a linear function in which the slope defined the transpiration efficiency (TE). Corn TE was greater than velvetleaf TE in all treatments during both trials. In the fall trial, corn TE was 6.3 g kg–1, 47% greater than that of velvetleaf TE. In the spring trial, TEs of both species were lower overall, and corn TE increased with declining water supply. Corn produced more biomass and leaf area than velvetleaf did at all water-supply levels. Velvetleaf partitioned more biomass to roots compared with shoots during early growth than corn did. The ability of corn to generate more leaf area and its investment in a greater proportion of biomass into root growth at all levels of water supply may enable it to more-effectively avoid velvetleaf interference under all levels of soil-water supply.

Agronomy Journa l • Volume 108 , I s sue 3 • 2016 Waterhemp is a diffi cult-to-control weed in maize, soybean [Glycine max (L.) Merr], and grain sorghum [Sorghum bicolor (L.) Moench] production, due to its competitive ability, outcrossing nature, high degree of genetic diversity, and resistance to multiple herbicide sites-ofaction (Horak and Loughlin, 2000; Hager et al., 2002; Steckel and Sprague, 2004; Steckel, 2007; Heap, 2015). Atrazine is still commonly used in maize and grain sorghum for PRE or POST control of waterhemp (Anderson et al., 1996) and other annual dicot weeds, in spite of hundreds of cases of triazine resistance occurring within Amaranthus spp. worldwide (Heap, 2014, 2015). Previous research reported that elevated rates of atrazine metabolism via GST activity contribute to atrazine POST resistance within two waterhemp populations (Ma et al., 2013). Th e MCR and ACR are both resistant to atrazine POST, and their responses have been compared with an herbicide-sensitive population, WCS (from Wayne County, Illinois) (Patzoldt et al., 2005; Hausman et al., 2011; Ma et al., 2013). Diff erences in PRE vs. POST activity of atrazine among several atrazine-resistant waterhemp populations identifi ed from Illinois were noted in previous studies (Patzoldt et al., 2003, 2005). In particular, an atrazine-resistant waterhemp population from Illinois (diff erent than MCR and ACR) was not resistant to atrazine PRE at a rate of 1.5 kg ha–1 (Patzoldt et al., 2003). Moreover, the ACR and MCR populations were not controlled but responded equally to atrazine POST at the rate of 560 g ha–1 (Hausman et al., 2011), and both populations demonstrated almost identical rates of atrazine metabolism (Ma et al., 2013) when 14C-atrazine was supplied using an excised-leaf assay (Ma et al., 2015). In addition to waterhemp, other dicot weed populations (most notably Abutilon theophrasti Medic.) have displayed non target-site resistance (NTSR) to atrazine POST (Anderson and Gronwald, 1987; Gronwald et al., 1989; Gray et al., 1996), and each has displayed enhanced rates of rapid metabolism via glutathione-atrazine conjugation (catalyzed by elevated GST activity) as the mechanism of resistance (Anderson and Gronwald, 1991; Gray et al., 1996). Th is is an important physiological factor to consider when studying NTSR mechanisms in weeds because GST enzymes are encoded by nuclear genes (Anderson and Gronwald, 1987; Patzoldt et al., 2003; Frova, 2006). In contrast, the target site for atrazine Differential Responses to Preemergence and Postemergence Atrazine in Two Atrazine-Resistant Waterhemp Populations

Field experiments were conducted in 2013 and 2014 to determine the influence of velvetleaf densities of 0, 0.125, 0.25, 0.5, 1, 2, 4, and 8 plants m−1of row on cotton growth and yield. The relationship between velvetleaf density and seed cotton yield was described by the hyperbolic decay regression model, which estimated that a density of 0.44 to 0.48 velvetleaf m−1of row would result in a seed cotton yield loss of 50%. Velvetleaf remained taller and thicker than cotton throughout the growing season. Both cotton height and stem diameter reduced with increasing velvetleaf density. Moreover, velvetleaf interference delayed cotton maturity, especially at velvetleaf densities of 1 to 8 plants m−1of row, and cotton boll number and weight, seed numbers per boll, and lint percentage were also reduced. Fiber quality was not influenced by weed density when analyzed over 2 yr; however, fiber length uniformity and micronaire were adversely affected in 2014. Velvetleaf intraspecific competition resulted in density-dependent effects on weed biomass, ranging from 97 to 204 g plant−1dry weight. Velvetleaf seed production per plant or per square meter was indicated by a logarithmic response. At a density of 1 plant m−1of cotton row, velvetleaf produced approximately 20,000 seeds m−2. The adverse impact of velvetleaf on cotton growth and development identified in this study have indicated the need for effective management of this species when the weed density is greater than 0.25 to 0.5 plant m−1of row and before the weed seed maturity.

Two begomoviruses were isolated in the northern Brazilian state of Para, infecting non-cultivated Hibiscus sp. and cultivated tomato (Solanum lycopersicum). The complete genomes (DNA-A and DNA-B) of the two viruses showed the typical organization of New World bipartite begomoviruses. Based on the species assignment criteria in the genus Begomovirus, each virus is a member of a new species. The virus from Hibiscus is most closely related to sida yellow mosaic Yucatan virus, while the tomato virus is most closely related to abutilon mosaic Brazil virus and corchorus mottle virus. Recombination events were detected in the DNA-A of the tomato virus, but not in the Hibiscus virus genome. We propose the names "hibiscus golden mosaic virus" (HGMV) and "tomato chlorotic leaf curl virus" (ToCLCV) for the viruses reported in this study.

To test the effect of adjuvant on the efficacy of herbicides in a fast and non-destructive way is very helpful for selecting a right spray adjuvant for herbicide, which is an important strategy to enhance the efficacy of herbicides, reduce application dose, and enhance environmental safety. Experiments were conducted in the laboratory and greenhouse to study the effect of 2 adjuvants - Methylated seed oil (MSO) and organosilicone on the efficacy of topramezone on grass weed giant foxtail (Setaria faberi Herrm.) and broadleaved weed velvetleaf (Abutilon theophrasti Medik.) using weed leaves chlorophyll fluorescence measurement and whole plant biomass test. The results indicated that the top leaf maximum quantum efficiency (Fv/Fm) of two weeds treated by herbicide mixed with MSO adjuvant was significantly lower than that of treated by herbicide alone from the 2–3 days after treatment, while the difference between treatments of herbicide mixed with organosilicone adjuvant and herbicide applied alone was not significant. Results of the whole-plant pot tests showed biomass of the treatment of topramezone mixed with MSO was significantly lower than that of herbicide applied alone. This is similar to the result of chlorophyll fluorescence test. Chlorophyll fluorescence measurement has proven to be an attractive tool for studying the effect of the adjuvants on the efficacy of herbicide.

The application of minimal doses of herbicides is very popular due to concerns about the negative impacts of herbicides on the environment and public health. Studies were conducted to estimate the possibility of using quick and non- destructive methods to investigate Chenopodium album L. and Abutilon theophrasti Medik. response to mesotrione. The studies were conducted in a controlled environment to determine the response of C. album and A. theophrasti to mesotrione using dose-response curves created based on plant dry weight, chlorophyll fluorescence parameters and chlorophyll content. The obtained effective dose values showed that the studied weeds were susceptible to reduced doses of mesotrione. ED95 values estimated for both species for dry weight and chlorophyll fluorescence parameters were lower than the recommended dose rate (120 g a.i. ha(-1)), with less than 85 g a.i. ha(-1) needed to achieve a reduction of 95%, compared with untreated plants, while ED95 value (A. theophrasti: 182 g a.i. ha(-1) and C. album: 180 g a.i. ha(-1)) for chlorophyll content for both species was above the recommended dose rates. Consequently, dry weight and the chlorophyll fluorescence parameters are suitable for estimating the plant response to mesotrione, while chlorophyll content is not.

Velvetleaf (Abutilon theophrasti), an annual plant in the family Malvaceae, is an important source of fiber and medicine (Flora of China 2007; Su et al. 2010). Dark brown lesions were observed on the leaves of A. theophrasti in the Herbal Garden of Jilin Agricultural University (125.23°E, 43.47°N), Jilin Province, China, in July 2015 and 2016, respectively. The disease incidence was about 20%. The lesions appeared initially as small, light brown spots on the leaves. These enlarged gradually and coalesced with others to form large spots having irregular edges. Finally, the central portions of the lesions broke open leaving small holes on the leaves. A small piece of tissue was cut from the lesion margin of 30 leaves and then surface sterilized in 75% ethanol for 30 s followed by 1.5% NaClO for 1 min, washed three times with sterilized distilled water, and then dried on sterilized filter paper. Each tissue piece was incubated on potato dextrose agar at 25°C in the dark for 7 days. Colonies formed and were light olive (after 3 days) and then became dark olive (after 7 days). The growth rate (colony radius) ranged from 3.5 to 5.2 mm per day. Conidia were hyaline, aseptate, both ends were bent slightly, and measured 21.9 to 28.0 (25.4 ± 1.4) μm in length and 3.2 to 5.8 (4.3 ± 0.6) μm in width. The hyphae were hyaline, septate, and branched. Appressoria were light to dark brown, solitary, with the outline roundish to ellipsoidal, and 7.3 to 9.8 × 4.8 to 6.3 μm in size. Setae were dark brown, two to five septate, and measured 79.2 to 162.6 μm in length. The morphological characteristics corresponded to Colletotrichum truncatum more clearly and directly (Damm et al. 2009). To further confirm the identity of the pathogen, DNA was extracted from one single-spore isolate, CT12. The following loci were amplified according to Weir et al. (2012): the internal transcribed spacer (ITS) region of ribosomal DNA and the glyceraldehyde-3-phosphate dehydrogenase (GAPDH), β-tubulin-2 (TUB2), and chitin synthase (CHS-1) genes. The numbers of base pairs matching were 548/550 for ITS, 225/228 for GAPDH, 241/242 for CHS-1, and 683/683 for TUB2 compared with the sequences of C. truncatum in GenBank (KX621963 for ITS, MK359986 for GAPDH, MK118057 for CHS-1, and MH925229 for TUB2). Maximum likelihood analysis of the combined four gene sequences and reference sequences of Colletotrichum spp. from GenBank and the results of the phylogenetic tree showed that CT12 belonged in C. truncatum with 100% bootstrap support. Sequences of the representative isolate CT12 were deposited in NCBI GenBank (MG993325 [ITS, 558 bp], MH038172 [GAPDH, 225 bp], MH038171 [TUB2, 683 bp], and MH038173 [CHS-1, 242 bp], respectively). Conidial suspension (10⁶ conidia/ml) of CT12 was sprayed on 10 healthy, 3-month-old velvetleaf leaves, and sterilized distilled water was sprayed on 10 healthy 3-month-old velvetleaf leaves as a control. The experiment was conducted three times. All plants were incubated in a controlled incubator with a 12-h photoperiod and 90% relative humidity at 25°C. After 5 days, necrotic lesions occurred on the inoculated leaves but not on the control plants. The same fungus was reisolated from the infected leaf tissues. C. truncatum has been reported to cause anthracnose on soybean, pepper, tomato, eggplant, muskmelon, chickpea, grapes, and other plants (Damm et al. 2009; Diao et al. 2014). To our knowledge, this is the first report of C. truncatum causing anthracnose on velvetleaf in China. The identification of the pathogen will provide a theoretical basis for the identification and control of the disease and reduce economic losses.

Velvetleaf, an annual broadleaf weed, is a common and troublesome weed of cropping systems worldwide. Laboratory and field experiments were conducted to determine the effects of environmental factors on germination and emergence of velvetleaf. Seeds germinated over a range of constant temperatures from 10 to 40 oC regardless of light conditions, but no germination occurred at temperature below 5 oC and beyond 50 oC. Seeds germinated at alternating temperature regimes of 15/5 to 40/30 oC, with maximum germination (>90%) at alternating temperatures of 40/30 oC. Germination was sensitive to water stress, and only 0.4% of the seeds germinated at the osmotic potential of -0.4 MPa. There was no germination at ? 0.6 MPa. Moreover, germination was reduced by saline and alkaline stresses and no germination occurred at ³ 150 mM NaCl or ³ 200 mM NaHCO3 concentrations. However, pH values from 5 to 9 had no effect on seed germination. Seedling emergence was significantly affected by burial depth and maximum emergence (78.1-85.6%) occurred at the 1-4 cm depth. The results of this study have contributed to our understanding of the germination and emergence of velvetleaf and should enhance our ability to improve control strategies in cropping systems in central China.

Holotrichia parallela damages seriously on peanut (Arachis hypogaea) pods. Elucidation of its flight and walking performance in the presence of different plants may provide an insight in its host selection process and an explanation to its strong olfactory preference to an attractive nonhost, castor bean (Ricinus communis). We determined the relationships among flight performance, mate choice, and body weight of H. parallela beetles, and then investigated their flight and walking patterns in the presence of known hosts and attractive nonhost plants using a flight mill and a locomotion compensator, respectively. Body weights were not related to mating success, regardless of sex. The flight proportion of selected females drastically decreased compared with nonselected females, nonselected males, and selected males. Within mated males, heavier individuals exhibited poorer flight performance than lighter ones. In flight bioassay, peanut showed an arrestment effect on virgin females. For walking activity factors (distance, time, and speed), the host plants velvetleaf (Abutilon theophrasti) and Siberian elm (Ulmus pumila) elicited the strongest responses in females and males, respectively. Interestingly, the most preferred adult host, Siberian elm, and the nonhost, castor bean, elicited the highest values of two orientation factors (orientation and upwind length) in females. The chemical similarity hypothesis, which states that feeding or oviposition of insects mistakenly on nonhost can be traced to their chemical similarity to actual hosts, could explain the attraction of H. parallela to castor bean.

Literary Dwaya means two, Bala Dwaya means two types of Bala i.e. Bala and Atibala. Bala means strength promoting, hence it bestows strength and is a tonic in general as well as rejuvenator for all kinds of Vataja disorders. The Bala is Sida cordifolia Linn. and Atibala is Abutilon indicum Linn. both belongs to Malvaceae family. Both are having Madhura Rasa, Madhura Vipaka and Sheeta Virya. In Brimhaniya Mahakashaya of Charaka Samhita it is enumerated that Vatyayani as Bala and Bhadroudini is Atibala. There are two varieties of Atibala one is big and the other is small. The big one is named as Abutilon hirtum where as the second one is named as Abutilon indicum Linn. which is smaller variety. In the Atharva Parishishta the Bala flowers can be used as Pushpabhisheka. The present study of Bala and Atibala reveals the pharmacological actions, their controversies, therapeutic application, etc. according to different Ayurvedic lexicons.

ed from meteorological records of Iowa State University, Ames. In deriving 1% it was assumed that 50% of total incident shortwave radiation lies within the 400 to 700 nm waveband. Since it was impractical to monitor incident light interception continuously^ measurements were taken only at each of the four harvest dates, just prior to harvesting. A line quantum sensor^, oriented parallel to row direction, was used to measure the photosynthetic photon flux density (FFFD) at 0.01, 0.19, and 0.38 m to either side of each selected row section at the soil surface) one reading was taken directly above the canopy. The six FFFD values measured at the soil surface were averaged to obtain a mean value of FFFD below the canopy of each plot. FFFD was recorded automatically at 0.5 s intervals by a micrologger^ and averaged over a 25 s time period to obtain a better estimate of light interception. All FFFD measurements were taken at local solar noon i 1 h. The US was then calculated for each plot using these FFFD measurements. LUE was calculated in the following manner. A quadratic function was fitted to a plot of LIE over time (jDAP). Since LIE was not measured at emergence, an estimated value was used, based on typical expected LAI of soybean or velvetleaf at emergence. Daily lo and instantaneous daily values of LIE predicted from the equation of the line were then used to calculate J, the total amount of incident light (in energy terms) intercepted by canopies of the various species proportions, summed over each harvest interval from emergence to final harvest^ J S(LIE X lo). The LUE of each plot was then calculated for each harvest 4 Model LI-191SB. LiCor Inc., Lincoln, NE 68504. ^ Model 2iX. Campbell ScientiHc Inc., Logan, UT 84321.

The development of techniques to non-destructively monitor allelochemical dynamics in soil using polydimethylsiloxane (PDMS) microtubing (silicone tubing microextraction, or STME) provides a means to test important ecological hypotheses regarding the roles of these compounds in plant-plant interactions. The objective of this study was to investigate the impact of intra- and interspecific competition on the exudation of thiophenes by marigolds (Tagetes patula L.). Marigolds were grown at a density of 1, 3 and 5 plants in pots (8.75 × 8.75 cm) containing two STME samplers. An additional treatment included one marigold surrounded by four velvetleaf (Abutilon theophrasti L.) plants. Marigold roots released two primary thiophenes, 3-buten-1-ynyl)-2,2′-bithienyl and α-terthienyl, which are readily absorbed by silicone microtubing. Thiophene exudation was monitored over the period 15–36 days after planting, at 2–5 day intervals. At the end of the study, root and soil samples were also analyzed for thiophene content. Thiophene production per plant increased over time, and thiophene release was strongly correlated with plant size. These results indicate that thiophene release in this study was passively controlled by resource availability. However, poor growth of velvetleaf plants competing with marigold suggests that thiophenes negatively influenced velvetleaf growth. This study, then, provides indirect evidence that thiophene exudation is insensitive to neighbor identity but differentially effective in inhibiting the growth of heterospecific neighbors.

A new species, Abutilon substellatum Phuph. & Poopath, is described and contrasted to its nearest ally, A. persicum (Burm. f.) Merr

Plant diseases have a direct impact on the productivity of crops, and therefore the early detection of diseases is crucial. Abutilon mosaic virus (AbMV) (family Geminiviridae; genus Begomovirus) is an important virus infecting ornamental crops throughout the world. Abutilon hybridum showing bright yellow mosaic symptoms were observed in gardens in Tumbaco, Ecuador. The infection was confirmed by Polymerase Chain Reaction (PCR) using degenerate begomovirus primers. The amplicon (∼500 bp) was sequenced, submitted to NCBI (KP877621) and showed 68.7–100% and 72.7–100% sequence identity with other begomoviruses at nucleotide and amino acid levels, respectively. In order to evaluate Raman spectroscopy as a diagnostic tool for AbMV infection, spectra of leaves from healthy and infected plants were recorded. Raman signals of carotenoids are the most important features and there is a significant decrease in the intensity of these bands when the plant is infected. The difference in the intensity of the bands, particularly the one at 1526 cm−1, is proposed as a basis for the early detection of viral infection in plants.

Growth stage of weeds can significantly affect the level of control at the moment of herbicide application. Maturation of plants usually lead to decreased sensitivity of plants. The aim of this research was to determine whether growth stage of weed species can affect the sensitivity of Chenopodium album and Abutilon theophrasti to mesotrione at the moment of application. Seeds of these species were sown in 5 days interval to ensure that at the moment of herbicide application Ch. album would be in stages of 2, 4, 6, 8 and 10 leaves and A. theophrasti in stages of 1, 2, 3, 4 and 5 leaves. When plants reached this stages herbicide Skaut (mesotrione 480 g/l) was applied in recommended dose rate 0.25 l/ha in tank-mix with adjuvant Alteox wet 40 (mineral oil (500 g/l) and polyoxyethylene alcohol (500 g/l)) in the dose rate 1 l/ha. The results showed that growth stage at the moment of application of mesotrione can significantly affects the sensitivity of both species to herbicide. The application of herbicides in the early growth stages (A. theophrasti - 1 leaf, Ch. Album - 2 and 4 leaves) resulted in total control of plants. With further maturation, sensitivity has decreased, in terms that the lowest effect was noted with A. theophrasti in growth stage of 5 leaves and Ch. album in growth stage of 10 leaves. Fenofaza razvoja korovskih biljaka u momentu primene herbicida može značajno uticati na njihovu osetljivost. Sa starenjem biljke najčešće dolazi do smanjenja osetljivosti biljaka. Obavljena su istraživanja kako bi se utvrdilo da li fenofaza razvoja biljaka u momentu primene mezotriona utiče na osetljivost Chenopodium album i Abutilon theophrasti. Setva semena ovih vrsta je obavljena u razmacima od po 5 dana kako bi se obezbedilo da u momentu primene herbicida biljke Ch. album budu u fazi 2, 4, 6, 8 i 10 listova, odnosno A. theophrasti u fazi 1, 2, 3, 4 i 5 listova. Kada su biljke dostigle navedene fenofaze razvoja primenjen je preparat Skaut (mezotrion 480 g/l) u količini primene 0,25 l/ha, kome je dodat ađuvant Alteox wet 40 (mineralno ulje (500 g/l) + polioksi alkohol (500 g/l)) u količini 1 l/ha. Dobijeni rezultati su pokazali da fenofaza razvoja u vreme primene mezotriona značajno utiče na osetljivost obe ispitivane vrste. Primena herbicida u najranijim fazama razvoja (A. theophrasti - 1 list; Ch. album - 2 i 4 lista) dovela je do potpunog propadanja biljaka. Sa daljim starenjem biljaka osetljivost se smanjivala, tako da je najslabiji efekat utvrđen kod biljaka A. theophrasti u fenofazi 5 listova, a kod biljaka Ch. album u fenofazi 10 listova.

This study was conducted to evaluate the effect of herbicidin, new natural herbicidal substances, derived from soil actinomycetes Streptomyces scopuliridis. Several weed species were subjected to examine the germination inhibition and herbicidal activity at the concentration from 100 to 2,000 ppm. There was no selectivity in germination inhibition and herbicidal activity against crops. Germination of Echinochloa oryzoides, Digitaria ciliaris, Abutilon theophrasti and Amaranthus retroflexus was inhibited completely when 7.81 ppm of extract was treated in petri dish. Pre-emergence application of herbicidin in soil condition showed low inhibition against weeds. However, post application of herbicidin in green house resulted in the necrosis of weeds at the concentration of 2,000 ppm. A. retroflexus was sensitive to herbicidin at the low concentration of 62.5 ppm, whereas E. oryzoides was tolerant to lower concentration of herbicidin until it became withered at the concentration of 2,000 ppm. In conclusion, herbicidal substances derived from S. scopuliridis herbicidin, which is consisted with herbicidin A and B, have dominant effect on germination and growth inhibition. On the other hand, herbicidin was insufficient to control gramineous weeds. In future, it will be needed to develop the combination of herbicidin with other herbicide or compounds to control gramineous weeds as well.

This study was conducted to investigate the ability for weed control of the shoot extract of sorghum (Sorghum bicolor (L.) Moench) and developing a sustainable weed management in organic farming. When the dried shoot powder was mixed with soil and treated with 2 ㎝ above the soil surface, the germination for Echinochloa crus-galli, Digitaria cilialis, Abutilon theophrasti and Amaranthus retroflexus was inhibited maxium 40%. The growth inhibition of germinated seedlings in the A. theophrasti and A. retroflexus was maxium 30% while it was less than 30% in the E. crus-galli and D. cilialis. Shoot extracts at rates above 25 ㎎ ml -1 was effective to inhibit germination of D. cilialis, A. theophrasti and A. retroflexus. The shoot extract concentration required for 50% of germination inhibition was 60 ㎎ ml -1 in the E. crus-galli, while it was less than 10 ㎎ ml -1 in the D. cilialis, A. theophrasti and A. retroflexus. For the foliar application, 11 adjuvants were tested at 0.5% and DOS70, TM15 and TDE7 were most effective adjuvants for the shoot extracts. DOS70 was most effective and provided up to 60% of weed control efficacy for the tested four weed species. Though herbicidal efficacy of sorghum shoot was not enough to give a proper weed control, it can be expected that long term use of sorghum shoots can provide gradual decrease in weed seeds and weed density.

Flaveria bidentis (L.) Kuntze, an invasive plant in China, has caused serious environmental and agricultural problems. A competition experiment with and without nitrogen fertilizer under field conditions was conducted to determine the competitive ability of the invasive plant species with two native species. The results showed that fertilization only increase relative growth rate of F. bidentis in the monoculture and the photosynthetic rates of the invasive species when it competed with Abutilon theophrasti. The growth of Leonurus heterophyllus was inhibited, while the growth of A. theophrasti was promoted by competition with F. bidentis. Nitrogen fertilizer addition significantly decreased the positive effect and increased the negative effect on A. theophrasti. The higher relative growth rate and net assimilation rate might give A. theophrasti a competitive advantage in comparison to L. heterophyllus in the competition with F. bidentis due to its greater ability to utilize available resources.

An alternative method to other technologies to clean up the soil, air and water pollution by heavy metals is phytoremediation. Therefore, a pot culture experiment was conducted at the College of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran, in 2014 to determine the potential absorption of cadmium by Portulaca oleracea (Common purslane), Solanum nigrum (Black nightshade), Abutilon theophrasti (Velvetleaf) and Taraxacum officinale (Dandelion). The type of experiment was completely randomized design with factorial arrangement and four replications. The soil in pot was treated with different rates of CdCl2.H2O (0 (control), 10, 20, 40, 60, and 80 mg Cd/kg soil) and the plants were sown. With increasing concentration levels, fresh weight and dry weight of shoots and roots of all plant species were reduced. The reduction severity was ranked according the following order, P. oleraceaA. theophrastiS. nigrumT. officinale. Bioconcentration factor (BCF), Translocation factor (TF) and Translocation efficiency (TE%) was ranked according the following order, T. officinaleS. nigrumA. theophrastiP. oleracea. The results of this study revealed that T. officinale and S. nigrum are effective species to phytoremediate Cd-contaminated soil.

Several different alkoxycarbonyl-substituted 2-benzoxazolinone moieties have been incorporated into a tetrahydroisoindoline-1,3-dione scaffold to provide 25 compounds (1a–1u and 2a–2d). The structures of these compounds were confirmed by 1H and 13C NMR, HRMS and X-ray single-crystal diffraction. Some of these compounds (1g, 1h, 1j, 1k) exhibited excellent herbicidal activities against Abutilon theophrasti, Amaranthus retroflexus and Echinochloa crus-galli at a rate of 375 g AI·ha−1. Among them, compounds 1h and 1j displayed the best post-emergence herbicidal effect against Abutilon theophrasti with ED50 values of 1.8 and 5.3 g AI·ha−1, respectively, which are superior to that of the commercial acifluorfen (44.3 g AI·ha−1). Field trials demonstrated that compound 1h exhibited similar herbicidal activity to a high concentration atrazine, and found to be safer for maize than atrazine. The results of this study therefore show that compound 1h could potentially be used as a post-emergence herbicide for maize fields.

The castor bean, Ricinus communis L., is a non-host plant for the large black chafer, Holotrichia parallela Motschulsky (Coleoptera: Scarabaeidae). In laboratory bioassays we found that this plant was no less attractive than the main host plant (peanut, Arachis hypogaea) and three food plant species: velvetleaf (Abutilon theophrasti), the glossy privet (Ligustrum lucidum), and the Siberian elm (Ulmus pumila). In field trapping experiments a Soxhlet extract of castor bean leaves caught more beetles than the optimal sex lure blend [(R)-(−)-linalool and (L)-isoleucine methyl ester blended in a ratio of 1:4], compared at equal doses (500 μl), and laboratory bioassays indicated that a castor bean plant could enhance the attractiveness of different blend ratios of sex lures. Olfactometer bioassays showed that males prefer volatiles emitted from different combinations of castor bean plant extracts and a signaling female over a female alone. In the presence of castor bean plants copulation rates of H. parallela were highest among all test environments both in laboratory bioassays (60%) and in field tests (70%). This study, combined with our previous observation of the feeding behavior of H. parallela adults on castor bean leaves, suggests that castor bean plants may provide an attractive but risky mating site for H. parallela beetles. The enhancement of male mate-location and copulation rate in the presence of castor bean plants can balance its paralytic effects on H. parallela after intake of potential toxins contained in its leaves.

Background and Purpose: Velvetleaf seed longevity and prolonged emergence complicate assessing appropriate time for its control. Estimating biological parameters (base temperature and base water potential) is a first step towards development of emergence predictive model for this weed species in summer crops. Since, development of new model is time consuming, the aim of the research was to provide the data set of biological thresholds for Croatian ecotype and then to compare it with Italian velvetleaf thresholds to assess the implementation of AlertInf predictive weed emergence model from Italy to Croatia. Materials and methods: Laboratory experiments were conducted with 100 seeds per three replicates at seven constant temperatures (4, 8, 12, 16, 20, 24, 28°C) to estimate base temperature (Tb) and at seven water stress levels (0.00, -0.05, -0.10, -0.25, -0.38, -0.50, -0.80, -1.00 MPa) to estimate base water potential (Ψb). Results: The highest germination occurred at temperature > 20°C with 3.6 days and at water stress level >- 0.25 MPa with 4.9 days to complete 50% of germination (t50). The slowest t50 occurred at 4°C (41.9 days) and < -0.38 MPa (10.1 days). Estimated Croatian velvetleaf biological parameters are: 4.5°C (Tb) and – 0.67 MPa (Ψb) with no significant difference compared to Italian ecotype, according to 95% confidence intervals overlapping. Conclusion: The results indicate that it could be possible to implement AlertInf model from Italy to Croatia for this weed species without additional adjustment. Nevertheless, next step of this implementation should include validation of estimated results in the field conditions. Key words: invasive weed species, velvetleaf, germination modelling, integrated weed management, base temperature, base water potential

Velvetleaf (Abutilon theophrasti Medic.) infestations negatively impact row crop production throughout the United States and Canada’s eastern provinces. To implement management strategies to control velvetleaf, managers need tools for differentiating it from crop plants. 5 Band, 7 Band, 8 Band, and 16 Band multispectral datasets simulating LANDSAT 3 plus a blue band, LANDSAT 8, WorldView 2, and WorldView 3 spectral bands, respectively were tested as input into the random forest algorithm for velvetleaf soybean [Glycine max L. (Merr.)] discrimination. During two separate greenhouse experiments in 2014, leaf reflectance measurements were obtained at the vegetative growth stage of velvetleaf plants and two soybean varieties. The reflectance measurements were collected with a plant contact probe attached to a hyperspectral spectroradiometer. Leaf hyperspectral reflectance measurements were convolved to the four multispectral datasets with computer software. Overall, user’s, and producer’s accuracies and kappa coefficient were employed to determine classification accuracies. Using the multispectral datasets as input, the random forest algorithm differentiated velvetleaf from the soybean varieties with accuracies ranging from 86.7% to 100%. 7 Band, 16 Band, 8 Band, and 5 Band datasets ranked or tied for the highest accuracies seventeen, sixteen, twelve, and one time, respectively. Kappa coefficients indicated an almost perfect agreement (i.e., kappa value, 0.81 - 1.0) to substantial agreement (i.e., kappa value, 0.61 - 0.80) between reference data and model predicted classes. This study was the first to demonstrate the application of the random forest machine learner and leaf multispectral reflectance data as tools to distinguish velvetleaf from soybean and to identify multispectral band combinations providing the best accuracies. Findings support further application of the random forest machine learner along with remotely-sensed multispectral data as tools for velvetleaf soybean discrimination with future implications for site-specific management of velvetleaf.

Article history: Received on: 07/07/2015 Revised on: 03/08/2015 Accepted on: 17/08/2015 Available online: 28/10/2015 Flavonoids have aroused considerable interest because of their potential beneficial effect on human health. Quercetin is one of the most abundant natural flavonoids present in medicinal plants. In the present study, a comparative phytochemical analysis of bioactive compounds from leaf and leaf derived callus of Abutilon indicum L. was carried out. Thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) analysis of methanolic extract of Abutilon leaf revealed the presence of quercetin. To test the effect of precursor in enhancing flavonoid content, in vitro studies were conducted by supplementing phenylalanine to actively growing callus cultures of Abutilon. More than threefold increase in quercetin content was obtained in elicitor induced callus compared to control.

A number of studies have shown that under some conditions plants may fully or partially compensate for leaf tissue loss; however, the mechanisms underlying compensatory responses are not well understood. Previous work demonstrated that the annual herb Abutilon theophrasti fully compensated for 75% defoliation, but only when grown in the absence of stem competition. We examined potential mechanisms of compensatory response and how they are influenced by resource limitation (i.e., competition for light). Full compensation for these annual plants was defined as equal final reproductive output in defoliated and control plants. In the current study we observed substantial compensation in defoliated plants growing at low density, despite losing 75% of leaf area prior to the onset of flowering. Plant responses associated with compensation included (1) increased reproductive efficiency, which may in turn may have resulted from increased canopy light penetration and transient increases in leaf-level photosynthetic rates; (2) greater allocation to reproduction (RA); (3) changes in biomass allocation from roots to shoots; (4) lower leaf longevity, and (5) increased percent fruit set. Although some of these responses were also observed in defoliated plants grown at high density, the inability of high-density plants to compensate appeared to result from competition for light; these plants delayed reproduction and continued to produce new leaves late in the growing season after low-density, defoliated plants had shifted allocation of resources to reproduction.

Pantoea ananatis is a bacterium associated with other microorganisms on Abutilon theophrasti Medik. roots. It converts 6-hydroxybenzoxazolin-2(3H)-one (BOA-6-OH), a hydroxylated derivative of the allelochemical benzoxazolin-2(3H)-one, into 6-hydroxy-5-nitrobenzo[d]oxazol-2(3H)-one. The compound was identified by NMR and mass spectrometric methods. In vitro synthesis succeeded with Pantoea protein, with isolated proteins from the Abutilon root surface or with horseradish peroxidase in the presence of nitrite and H2O2. Nitro-BOA-6-OH is completely degraded further by Pantoea ananatis and Abutilon root surface proteins. Under laboratory conditions, 6-hydroxy-5-nitrobenzo[d]oxazol-2(3H)-one inhibits Lepidium sativum seedling growth whereas Abutilon theophrasti is much less affected. Although biodegradable, an agricultural use of 6-hydroxy-5-nitrobenzo[d]oxazol-2(3H)-one is undesirable because of the high toxicity of nitro aromatic compounds to mammals.

Natural history observations are presented for 15 species of leaf-mining chrysomelid beetles, including previously unrecorded details of mine characteristics as well as oviposition and feeding habits of adults. New larval host records include Ceanothus velutinus Douglas ex Hook. (Rhamnaceae) for Baliosus californicus (Horn); Betula lenta L. (Betulaceae), Castanea dentata (Marshall) Borkh., and Quercus velutina Lam. (Fagaceae) for Baliosus nervosus (Panzer); Abutilon Mill. (Malvaceae) for Stenopodius texanus Schaeffer; Ambrosia artemisiifolia L. (Asteraceae) for Sumitrosis inaequalis (Weber); Celastrus orbiculatus Thunb. (Celastraceae) for Sumitrosis rosea (Weber); and Fallopia scandens (L.) Holub (Polygonaceae) for Mantura floridana Crotch.

Tank-mix adjuvant has the potential to improve the weed control efficacy of post-emergence herbicides. In order to study the synergistic effect of adjuvant, the effects of different rates of fomesafen alone or applied methylated soybean oil adjuvant (MSO) were sprayed on redroot pigweed, abutilon and black nightshade under greenhouse condition. The results showed that fomesafen had different performance on the three weeds, and MSO adjuvant could effectively increase the control. The nightshade control was lower than other two weeds with all the fomesafen doses from 131.25 to 506.25 ga.i. • hm -2 with or without adjuvant. The control of abutilon was between the black nightshade and the redroot pigweed, and had better control at 375 ga.i. • hm -2 with adjuvant or 506.25 ga.i. • hm -2 alone or with adjuvant respectively. The results indicated that mixing adjuvant with fomesafen improved the control on weeds, especially at the low rate. Black nightshade was more difficult to control. The redroot pigweed had the most susceptibility to fomesafen alone or with adjuvant.

Tomato yellow leaf curl virus (TYLCV) causes huge losses to tomato production worldwide. In July 2011 and July–August 2012, we screened for potential TYLCV hosts in a tomato-growing area in Shandong Province, the core vegetable-producing region in China. PCR detection showed that 5 species of plants, Zinnia elegans, Acalypha australis, Gossypium hirsutum, Abutilon theophrasti, and Nicotiana tabacum, were infected. Full genomic sequences of the new TYLCV isolates were obtained and submitted for sequence analysis. Sequence alignment and similarity analysis showed that they all belonged to the TYLCV-IL strain.

Theoretical models predict that seed size and seed-bank persistence evolve interdependently, such that strong selection for one trait corresponds with weak selection for the other. This framework has been supported and rejected by empirical data, and thus, conclusive evidence is lacking. We expanded the seed size–persistence framework to include seed-coat thickness, a defence trait previously correlated with seed survival in soil. To do this, we usedAbutilon theophrastiaccessions with varied evolutionary histories and we quantified associations among seed traits including morphology, size, coat thickness, dormancy (percentage of viable seeds that fail to germinate under optimum conditions) and seed-bank persistence (percentage of viable seeds remaining after 1 year of burial). Statistical models were developed to test the hypothesis that combined measurements of seed-coat thickness and seed size better explain variability in seed-bank persistence than seed-size data alone. Results indicated that measurements of seed size (length, width, mass) were negatively correlated with coat:width ratio (coat thickness relative to seed width) and coat:mass ratio (coat thickness relative to seed mass). Accessions characterized by smaller seeds with proportionally thicker seed coats were more dormant and more persistent in soil than accessions characterized by larger seeds with proportionally thinner seed coats. Seed-coat thickness data improved the explanatory power of logistic regression models for seed-size effects on both seed-bank persistence and dormancy. These results indicate that supplementing seed-size data with seed-defence data may clarify previously reported contradictory results regarding trade-offs between seed size and seed-bank persistence.

Trap cropping is a useful tool in sustainable pest management. Trap crops usually target a single species or genus of insect pests. In this study, we assessed the potential of velvetleaf (Abutilon theophrasti) as a trap crop for two distant insect species, Bemisia tabaci and Sylepta derogata in Chinese cotton fields from 2006 to 2009. Under laboratory conditions, velvetleaf, a known trap plant of B. tabaci, was preferred over cotton by S. derogata for oviposition, and the subsequent offspring had greater survival and faster development on velvetleaf than cotton. Field-plot trials showed that population densities of S. derogata were 46–110 times greater on velvetleaf than on cotton, respectively. Commercial field trials indicated that S. derogata density and leaf damage were 79–90 % and 83–94 % lower in cotton fields inter-planted with sprayed velvetleaf strips than without them, respectively; whereas densities of B. tabaci were 21–51 % lower in fields with sprayed velvetleaf strips than in those without. At >10 m from velvetleaf strips, densities of B. tabaci and S. derogata in cotton gradually increased. Velvetleaf strips were an effective trap crop for simultaneous management of B. tabaci and S. derogata in cotton fields.

This paper studied wettability of several typical plant leaves such as abutilon, Jerusalem artichoke and sunflower, contact angle of several leaves were measured through the contact angle measuring instrument, which were 41.5°, 46.3°and 43.6°respectively. Microstructure of abutilon, Jerusalem artichoke and sunflower leaves were observed by scanning electron microscopy, It found that several typical plant leaves are composite structure of micron scale and nanoscale, covered some long needle-like spikes, this feature has an important influence on hydrophilicity. According to wenzel model, the paper analyzed the relationship between hydrophilicity and microstructures of several plant leaves.