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The article reviews the concept and technology of pest risk assessment for the spread of quarantine species based on ecological and geographical analysis and ecological niche modeling. Using a quarantine species Ipomoea hederacea (L.) Jacq. as an example, we calculated the ecological requirements of the species. The main ecological factors limiting the spread of I. hederacea were determined and the ecological amplitudes of the species in relation to each factor limiting its distribution were quantitatively estimated. We identified ecologically suitable habitats and compiled a map of the ecological-geographical niche of the species using specially created environmental maps based on the obtained data of the ecological limits of the species. Using the map of the ecological-geographical niche, the I. hederacea distribution risk in the regions of the Russian Federation was estimated. Similar maps can be used for basis of quantitative as well as targeted risk assessment of penetration and establishment of harmful organisms. Obtained information will be useful to compile lists of quarantine species, estimate the potential areas of geographic distribution of pests into Russian Federation, and make decisions for introduction of effective phytosanitary measures to prevent the penetration of these invasive organisms. It can also be used as the basis for organizing and conducting phytosanitary monitoring in the Russian Federation.

A field experiment on “Integrated Weed Management for preseasonal sugarcane” was conducted for three consecutive years at Central Sugarcane Research Station, Padegaon, Tal Phaltan District Satara, Maharashtra, India during 2015-16 to 2017-18 to find out tank mix optimum combination dose of post emergence herbicide for effective control in sugarcane. Dominant weeds observed in sugarcane crop were Brachiaria eruciformis, Cyperus rotundous, Alternanthera sessils, Parthenium hysterophorus L., Euphorbia geniculata Linn., Cardiosoermum lalicacabum, Ipomoea hederacea and Hylandis latiprosa. The result showed that mean total weed count and weed dry weight reduced with post emergence application of metribuzin @ 0.50 kg a.i.ha-1 + 2, 4-D @ 1.00 kg a.i. ha-1 at 25 DAP fb hoeing at 60 and 90 DAP and found at par with treatment post emergence application of metribuzin @ 1 kg a.i ha-1 + 2, 4-D @ 1 kg a.i. ha-1 at 25 DAP fb hoeing at 60 and 90 DAP. Among the herbicidal treatments, post emergence application of metribuzin @ 0.50 kg a.i ha-1 + 2, 4-D @ 1 kg a.i. ha-1 at 25 DAP fb hoeing at 60 and 90 DAP recorded significantly the highest germination per cent (66.73 %), number of internodes per cane (22) and average cane weight (1.93 kg) over all herbicidal treatments which was at par with pre emergence spray of metribuzin @1 kg a.i. ha-1 and post emergence spray of 2,4-D @1kg a.i. ha-1 at 60 DAP fb hoeing at 90 DAP for number of internodes per cane (21.90) and average cane weight (1.92 kg). Among the herbicidal treatments, maximum weed control efficiency of 60.59 %, 56.38 % and 75.99 % was found in treatment of post emergence application of metribuzin @ 0.50 kg a.i. ha-1+ 2,4-D @ 1.00 kg a.i. ha-1 at 25 DAP fb hoeing at 60 and 90 DAP to sugarcane crop at 30, 60 and 90 days after application, respectively followed by post emergence application of metribuzin @ 1 kg a.i ha-1 + 2, 4-D @ 1 kg a.i. ha-1 at 25 DAP with hoeing at 60 and 90 DAP. Similarly, the significantly highest cane yield (155.21 t ha-1) and CCS yield (21.38 t ha-1) was recorded by same treatment over all herbicidal treatments which was at par with treatment metribuzin @1 kg a.i. ha-1 as pre emergence, 2,4-D @1 kg a.i. ha-1 as post emergence application at 60 DAP fb hoeing at 90 DAP for CCS yield. The maximum net return (Rs. 278454) and benefit cost ratio (3.13) was also reported by same treatment followed by post emergence application of metribuzin @1.00 kg a.i. ha-1 + 2,4-D @ 0.50 kg a.i. ha-1 at 25 DAP fb hoeing at 60 and 90 DAP. The cane quality like commercial cane sugar %, sucrose %, brix (00) and purity % was not affected by hand weeding, mechanical weed control and application of any herbicide.

Amaç: Ipomoea spp. ve Convolvulus spp. Convolvulaceae familyasına ait bitkilerden olup, tek veya çok yıllık olarak dünyada yaygın olarak bulunan istilacı yabancı otlardandır. Pek çok kültür bitkisinde sorun olan ve günümüzde istilacı özelliği ile ön plana çıkan Ipomoea ve Convolvulus türlerinin, yaygınlık ve yoğunluklarının belirlenmesi amacıyla Akdeniz bölgesinde sürvey çalışması yapılmıştır. Materyal ve Metot: Akdeniz bölgesinde bulunan Antalya, Adana, Mersin, Hatay, Kahramanmaraş ve Osmaniye illerinde yapılan sürveylerde, her bir il merkezi başlangıç kabul edilmiştir. Sürveyler sırasında her 10 km’de bir rastlantısal olarak durulmuş ve en yakın tarım alanını temsil edecek şekilde 1 da’lık alandan örnekler alınmıştır. Her bir örnekleme noktasına 1m2’lik çerçeveden tesadüfi olarak 5 kez atılarak yabancı ot türlerinin sayımları yapılmıştır. Bulgular: Akdeniz bölgesi genelinde Convolvulaceae familyasından Convolvulus cinsine ait 5 ve Ipomoea cinsine ait 3 olmak üzere 8 yabancı ot türü belirlenmiştir. Bunların türleri, yaygınlık (%) ve yoğunlukları (adet/m2), sırasıyla, Convolvulus arvensis L. (52.32 ve 0.57), Convolvulus scammonia L. (0.86 ve >0.01), Convolvulus stachydifolius Coisy (0.69 ve 0.01), Convolvulus betonicifolius Mill. (0.52 ve >0.01),Convolvulus galaticus Roston. ex Choisy (0.17 ve >0.01), Ipomoea triloba L. (9.12 ve 0.13), Ipomoea hederacea (Linn) Jacq. (3.44 ve 0.02) ve Ipomoea purpurea (L.) Roth. (1.20 ve 0.01)’dır.

Residual herbicides are routinely applied to control troublesome weeds in pumpkin production. Fluridone and acetochlor, Groups 12 and 15 herbicides, respectively, provide broad-spectrum PRE weed control. Field research was conducted in Virginia and New Jersey to evaluate pumpkin tolerance and weed control to PRE herbicides. Treatments consisted of fomesafen at two rates, ethalfluralin, clomazone, halosulfuron, fluridone, S-metolachlor, acetochlor emulsifiable concentrate (EC), acetochlor microencapsulated (ME), and no herbicide. At one site, fluridone, acetochlor EC, acetochlor ME, and halosulfuron injured pumpkin 81%, 39%, 34%, and 35%, respectively, at 14 d after planting (DAP); crop injury at the second site was 40%, 8%, 19%, and 33%, respectively. Differences in injury between the two sites may have been due to the amount and timing of rainfall after herbicides were applied. Fluridone provided 91% control of ivyleaf morningglory and 100% control of common ragweed at 28 DAP. Acetochlor EC controlled redroot pigweed 100%. Pumpkin treated with S-metolachlor produced the most yield (10,764 fruits ha–1) despite broadcasting over the planted row; labeling requires a directed application to row-middles. A separate study specifically evaluated fluridone applied PRE at 42, 84, 126, 168, 252, 336, and 672 g ai ha–1. Fluridone resulted in pumpkin injury ≥95% when applied at rates of ≥168 g ai ha–1; significant yield loss was noted when the herbicide was applied at rates >42 g ai ha–1. We concluded that fluridone and acetochlor formulations are unacceptable candidates for pumpkin production.Nomenclature: Acetochlor; clomazone; ethalfluralin; fomesafen; fluridone; halosulfuron; Smetolachlor; common ragweed; Ambrosia artemisiifolia L.; ivyleaf morningglory, Ipomoea hederacea Jacq.; redroot pigweed, Amaranthus retroflexus L.; pumpkin, Cucurbita pepo L.

Premise Darwin proposed that self-pollination in allegedly outcrossing species might act as a reproductive assurance mechanism when pollinators or mates are scarce; however, in natural populations, the benefits of selfing may be opposed by seed discounting and inbreeding depression. While empirical studies show variation among species and populations in the magnitude of reproductive assurance, little is known about the counterbalancing effects of inbreeding depression. Methods By comparing the female reproductive success of emasculated and open-pollinated flowers, we assessed the reproductive assurance hypothesis in two Mexican populations of Ipomoea hederacea. In one population, we assessed temporal variation in reproductive assurance for three years. We evaluated inbreeding depression on seed production, seedling germination, and dry plant mass by contrasting self- and cross-hand pollination treatments in one population for two years. Result The contribution of self-pollination to female reproductive success was high and consistent between populations, but there was variation in reproductive assurance across years. Inbreeding depression was absent in the early stages of progeny development, but there was a small negative effect of inbreeding in the probability of germination and the mass of adult progeny. Conclusions Self-pollination provided significant reproductive assurance in I. hederacea but this contribution was variable across time. The contribution of reproductive assurance is probably reduced by inbreeding depression in later stages of progeny development, but this counter effect was small in the study populations. This study supports the hypothesis that reproductive assurance with limited inbreeding depression is likely an important selective force in the evolution of self-pollination in the genus Ipomoea.

Agricultural impacts of climate change include direct effects on crop plants and indirect effects, such as changes to the distributions and competitiveness of weed species. In the northeastern United States, warming temperatures are likely to result in periods of soil moisture deficit and changes to weed communities. Ivyleaf morningglory (IMG, Ipomoea hederacea Jacq.) is a summer annual vine that competes with field crops and interferes with harvesting. Climate change may increase the competitive effects of IMG on northeastern U.S. field crops. We conducted a greenhouse study to evaluate the effects of IMG on corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] under drought and non-drought conditions. The drought treatment was crossed against an IMG competition treatment with five levels: one crop plant without IMG plants, one crop plant with one, two, or three IMG plants, and one IMG plant without crop plants. Both drought and IMG (presence or biomass) reduced the biomass of corn and soybean (P < 0.05). Drought and IMG (presence) reduced soybean pod production (P < 0.001). IMG biomass was reduced by drought and the presence of corn (P < 0.001). Across all competition treatments, drought reduced IMG biomass by 71% in the corn experiment and 79% in the soybean experiment, compared with a corn biomass reduction of 50% and a soybean biomass reduction of 58%. Well-designed management programs should mitigate the risks associated with stressors such as IMG and drought, which may threaten northeastern U.S. field crop production under climate change.

Ipomoea spp. can be referred to as an ornamental plant or a pervasive weed depending on the context. Ipomoea spp. inhabit disturbed areas such as crop fields, lawns, roadways, and waste sites across the world. There are approximately 600 species belonging to the Ipomoea genus; but the most common weedy species include Ipomoea hederacea, Ipomoea lacunosa, and Ipomoea purpurea. While the species exhibit differential phenotypes, the biology and management is nearly identical between the three species. Ipomoea spp. can cause significant field and vegetable crop yield reductions, and the esthetics of ornamentals and turf can be marred if not controlled. While herbicides are commonly used to control Ipomoea spp., biological, cultural, and mechanical tactics can be utilized to effectively control plants inhabiting disturbed areas.

SummaryCharacter displacement can play a major role in species ecology and evolution, however, research testing whether character displacement can influence the evolution of root traits in plant systems remains scarce in the literature. Here we investigated the potential that character displacement may influence the evolution of root traits using two closely related morning glory species,Ipomoea purpureaandI. hederacea.We performed a field experiment where we grew the common morning glory,I. purpurea, in the presence and absence of competition fromI. hederaceaand examined the potential that the process of character displacement could influence the evolution of root traits.We found maternal line variation in root phenotypes and evidence that belowground competition acts as an agent of selection on these traits. Our test of character displacement, however, showed evidence of characterconvergence on our measure of root architecture rather thandisplacement. These results suggest that plants may be constrained by their local environments to express a phenotype that enhances fitness. Therefore, the conditions of the competitive environment experienced by a plant may influence the potential for character convergence or displacement to influence the evolution of root traits.

To determine the spectrum of weed control and peanut tolerance with pyroxasulfone in Oklahoma. Study Design: Randomized complete block design with four replications. Place and Duration of Study: Oklahoma State University Caddo Research Station near Ft. Cobb (35.091o N, 98.275o W) in southwestern Oklahoma during the 2013-2014 growing seasons. Methodology: Herbicides were applied with a CO2 compressed air backpack sprayer using Teejet 110015XR nozzles that delivered 93 L ha-1 at 180kPa. Weed control and peanut injury were visually estimated on a scale of 0 indicating no control or plant death to 100 indicating complete control or plant death, relative to the untreated control. Peanut yields were obtained by digging each plot separately, air-drying in the field for 4 to 7 d, and harvesting peanut pods from each plot with a combine. Visual estimates of weed control and peanut yield were subjected to analysis of variance to test effects of postemergence (POST) herbicide and application timing and means were compared with Fisher’s Protected LSD test (0.05). Results: In 2013, only treatments that controlled Urochloa texana > 85% were those that included pendimethalin plus pyroxasulfone applied preemergence (PRE) and imazapic applied late postemergence (LPOST). Ipomoea hederacea control using either pendimethalin applied preplant incorporated (PPI) or flumioxazin applied PRE and imazethapyr applied POST was > 75%. In 2014, herbicide systems that included imazapic applied POST controlled I. hederacea at least 98% while no other herbicide systems provided better than 78% control. Peanut stunting (4 to 13%) was observed in 2013 with all PPI and PRE treatments. In 2013 and 2014, pyroxasulfone plus pendimethalin systems applied PRE followed by imazapic applied LPOST produced the greatest peanut stunting. Conclusion: These results indicate that pyroxasulfone is an effective herbicide for weed control in Oklahoma peanut production. Although no peanut yield reductions were observed, the early season stunting in isolated instances should be noted.

Field experiments were conducted in Louisiana and Mississippi from 2011 through 2013 to evaluate crop injury, weed control, and yield in field corn following pyroxasulfone applied PRE and POST. Pyroxasulfone PRE or POST did not injure corn at any evaluation. Barnyardgrass control was not improved with the addition of any POST treatment to pyroxasulfone alone or atrazine plus pyroxasulfone PRE; however, all POST treatments increased barnyardgrass control to at least 95% at all evaluations following atrazine PRE. All treatments that contained a PRE followed by POST application controlled browntop millet ≥90% at all evaluations. All POST treatments increased ivyleaf morningglory control to ≥92% following atrazine or pyroxasulfone alone PRE. However, control with atrazine plus pyroxasulfone PRE was similar or greater 28 d after POST than all treatments that received a POST application. In the absence of a POST treatment, pyroxasulfone or atrazine plus pyroxasulfone PRE controlled Palmer amaranth 93 to 96% at all evaluations, but atrazine alone PRE provided 84, 82, and 66% control 7, 14, and 28 d after POST, respectively. All programs that contained a PRE followed by POST herbicide treatment controlled Palmer amaranth >90% at all evaluations. Corn yield following all treatments except atrazine alone PRE and the nontreated were similar and ranged from 10990 to 12330 kg ha-1. This research demonstrated that pyroxasulfone can be a valuable tool for weed management in a corn weed management program.Nomenclature: Atrazine; glyphosate; pyroxasulfone; barnyardgrass, Echinochloa crus-galli (L.) Beauv. ECHCG; browntop millet, Urochloa ramosa (L.) Nguyen PANRA; ivyleaf morningglory, Ipomoea hederacea Jacq. IPOHE; Palmer amaranth, Amaranthus palmeri S. Wats. AMAPA; corn, Zea mays L.

Seeds of Ipomoea hederacea Jacq. (family: Convolvulaceae) are traditionally used to treat high blood pressure and cardiac diseases.Present study was conducted to validate the traditional claim and explore the possible mechanism(s) of antihypertensive effects of I. hederacea.Aqueous-ethanolic extract and activity based fractions of I. hederacea were evaluated using invasive blood pressure measuring technique, isolated tissue experiments, fructose induced hypertension/metabolic syndrome and biochemical analysis.Phytochemical analysis of active fraction was performed with aim to identify chemical composition of I. hederacea seeds. LC-MS analysis was also performed to identify the compounds proposed to be present in active fraction of I. hederacea seeds.Crude extract/fractions of I. hederacea showed dose (0.01-100 mg/kg) dependent significant hypotensive effect in normotensive anesthetized rats, similar to verapamil (0.01-30 mg/kg). Pretreatment with hexamethonium and atropine mediated no significant changes in hypotensive effect of butanol fraction of I. hederacea (Ih.Bn) at 3 mg/kg dose. However, a significant decrease in the hypotensive effect of Ih.Bn 3 mg/kg (-34.82 ± 3.36%; p 0.05) was observed in the presence of L-NAME (20 mg/kg). Similarly, Ih.Bn (3 mg/kg) showed no significant effect on angiotensin-II response. However, response of phenylephrine (45.60 ± 9.63%; p 0.05) and dobutamine (18.25 ± 2.10%; p 0.01) was significantly decreased in the presence of Ih.Bn 3 mg/kg. Ih.Bn also exhibited dose dependent (0.01-100 mg/kg) antihypertensive effect in fructose induced hypertensive rats, similar to verapamil (0.01-30 mg/kg). Concomitant treatment with Ih.Bn (3, 10 and 30 mg/kg) for six weeks showed a dose dependent profound protection with significant (p 0.01) effect at 30 mg/kg against fructose induced basal mean arterial pressure (142.2 ± 4.62 mmHg). Ih.Bn did not significantly change response of PE, Ang-II and Epi was observed in invasive and ex vivo techniques. However, Ih.Bn significantly (p 0.01; p 0.001) prevented against decrease in vascular response of acetylcholine in anesthetized rats and in isolated aorta of rat. A significant dose dependent decrease in triglyceride and glucose level (p 0.001), and increase in HDL level (p 0.05) was observed in Ih.Bn treated groups. Results of LC-MS analysis of Ih.Bn showed the presence of 24 compounds that belong to different chemical classes, including carboxylic acid, flavonoids, oligopeptides and tripeptide that are known to have antihypertensive and vasorelaxant properties.Results of present study indicate the presence of hypotensive/antihypertensive effect in crude extract/fractions of I. hederacea with most potent effect shown by butanol fraction (Ih.Bn), possibly mediated through α

We have recently reported that methanolic extracts from Ipomoea involucrata P. Beauv. (Convolvulaceae) exhibited particular antisickling properties coupled with the potential to reverse sickled blood and reduce stress in sickle cell patients1. In light of its possible medicinal benefits the MeOH plant extract was analysed for twenty bioactives by high performance liquid chromatographic (HPLC) equipped with UV-detector. Chlorogenic acid (33.72±0.24 mg/g. dry wt. leaves), ferulic acid (15.60±3.46 mg/g. dry wt. leaves), hesperidin (6.71±1.57 mg/g. dry wt. leaves), lutein (2.55±0.09 mg/g. dry wt. leaves), resveratrol (2.54±0.28 mg/g. dry wt. leaves), coumaric acid (1.75±0.17 mg/g. dry wt. leaves), myricetin (1.70±0.00 mg/g. dry wt. leaves), kaempferol (0.93±0.71 mg/g. dry wt. leaves) and rutin (0.80±0.43 mg/g. dry wt. leaves) were the nine bioactives detected. The high levels of the major compounds (chlorogenic acid, ferulic acid and hesperidin) were similar to that of leaves of other Ipomoea sp.2-4 Hesperidin was first reported in this study among the Ipomoea sp. The leaves has relatively higher levels of coumaric acid than I. mauritiana; ferulic acid, resveratrol and lutein than I. batatas; and similar levels of myricetin to that in I. batatas.2,5-6 Ferulic acid in I. hederacea, myricetin in I. aquatica, rutin in I. batatas; and coumarin in I. cairica, Ipomoea digitata L., Ipomoea hederacea, I. pes-caprae , I. pes-tigridis, I. sepiaria and I. batatas were also detected but not quantified.3 The identified compounds could significantly contribute to the medicinal properties of the plant.3 A future investigation will carry out to evaluate the antisickling properties coupled with the potential to reduce stress in sickle cell patients of the isolated constituents.

Sclerotinia blight, caused by the soilborne fungus Sclerotinia minor Jagger, is a major disease of peanut (Arachis hypogaea L.) in parts of west Texas. Previous reports have indicated that annual weed species may serve as collateral hosts for S. minor (2). Several Ipomoea spp. are commonly found in peanut fields throughout the region. In September of 2007, Ipomoea hederacea and I. coccinea plants with bleached, shredded stems, and signs of black sclerotia were collected from a field known to be infested with S. minor. Symptomatic stem sections were rinsed in tap water, surface disinfested in 0.5% sodium hypochlorite for 1 min, air dried, and plated on potato dextrose agar (PDA). Pure cultures of S. minor consisting of white, fluffy mycelia and small ( References: (1) Anonymous. Index of Plant Diseases in the United States. USDA Handb. No. 165, 1960. (2) J. E. Hollowell et al. Plant Dis. 87:197, 2003. (3) D. M. Porter and H. A. Melouk. Sclerotinia blight. Page 34 in: Compendium of Peanut Diseases. 2nd ed. N. Kokalis-Burelle et al., eds. The American Phytopathologicial Society, St. Paul, MN, 1997.

A series of novel α-amino phosphonate derivatives containing a uracil moiety 3a-3l were designed and synthesized by a Lewis acid (magnesium perchlorate) catalyzed the Kabachnik-Fields reaction. The bioassays {in vitro, in vivo [Glass House 1 (GH1) and Glass House 2 (GH2)]} showed that most of compounds 3 exhibited excellent and selective herbicidal activities; for example, in GH1 test, compounds 3b, 3d, 3f, 3h and 3j showed excellent and wide spectrum herbicidal activities at the dose of 1000 g/ha, and compounds 3b and 3j exhibited 100% inhibition activities against the four plants in both post- and pre-emergence treatments. Moreover, most of compounds 3 showed higher inhibition against Amaranthus retroflexus and Digitaria sanguinalis than Glyphosate did in pre-emergence treatment. In GH2 test, the four compounds (3b, 3d, 3h and 3j) exhibited 100% inhibition against Solanum nigrum, Amaranthus retroflexus and Ipomoea hederacea in post-emergence treatment and displayed 100% inhibition against Solanum nigrum, Amaranthus retroflexus in pre-emergence treatment at the rate of 250 g/ha, and compound 3b showed the best and broad spectrum herbicidal activities against the six test plants. However, the four compounds displayed weaker herbicidal activities against Lolium perenne and Echinochloa crus-galli than the other four plants at the rate of 250 g/ha in both pre- and post-emergence treatments. So, compounds 3 can be used as a lead compound for further structure optimization for developing potential selective herbicidal agent. Their preliminary structure-activity relationships were also investigated.

Tomato chlorosis virus (ToCV) is a whitefly-transmitted crinivirus that causes interveinal chlorosis and bronzing on tomato leaves. Although outbreaks of ToCV have been reported in many countries, the virus was not reported in Korea until 2013. To identify weed hosts of ToCV that may serve as virus reservoirs, we analyzed various weeds that were growing together with ToCV-infected tomatoes and viruliferous Bemisia tabaci in a tomato greenhouse. We performed reverse transcription-polymerase chain reaction (RT-PCR) analysis of root samples from 148 samples of 61 species from 24 families of plants grown in the greenhouse to avoid possible ToCV contamination by whiteflies on leaves. Seventeen weed species were identified as ToCV hosts based on RT-PCR results of root samples: Conyza canadensis, Erigeron annuus, Sonchus asper, Youngia japonica, Trigonotis peduncularis, Cardamine flexuosa, Cerastium glomeratum, Stellaria media, Chenopodium album, Ipomoea hederacea, Quamoclit coccinea, Vicia angustifolia var. segetilis, V. tetrasperma, Phytolacca americana, Mazus pumilus, Solanum americanum and S. nigrum. The amplicons obtained by RT-PCR were confirmed as ToCV by sequence analysis. Life cycle analysis of the weeds indicated that each weed could play an important role as a “green bridge” or virus reservoir between tomato cultivation seasons. This is the first report documenting the possible occurrence of ToCV in tomato plants based on weed life cycles.

The efficacy, absorption, translocation, and metabolism of thiencarbazone-methyl (TCM) in hedge bindweed, field bindweed, ivyleaf morningglory, tall morningglory, and wild buckwheat were evaluated in greenhouse experiments and field trials. Forty-eight hours after foliar microapplication,14C-TCM absorption was highest in ivyleaf morningglory (60%), followed by field bindweed (50%), wild buckwheat (35%), tall morningglory (17%), and hedge bindweed (9%). In all species,14C-TCM was translocated systemically. By 24 h after application,14C-TCM was detected in all parts of the plants. The translocation pattern is species-specific, with more translocation in tall morningglory and wild buckwheat. In all vining weeds14C-TCM was almost not metabolized whereas corn metabolized almost all14C-TCM 48 h after application. The efficacy of TCM was analyzed using dose–response curves. Wild buckwheat had the lowest value for the dose at which 50% of the activity occurs (2.1 g ai ha−1TCM), followed by hedge bindweed and ivyleaf morningglory. Field studies confirmed the high control of wild buckwheat with TCM. Even at the lowest tested concentration of TCM, wild buckwheat was controlled by over 90%. In contrast, efficacy of TCM in field trials against perennial vining weeds was very low, 25% for field bindweed and 65% against hedge bindweed. Control efficacy could be well explained by the translocation pattern of TCM in vining weeds.

Disentangling the historical evolutionary processes that contribute to patterns of phenotypic and genetic variation is important for understanding contemporary patterns of both traits of interest and genetic diversity of a species. Ipomoea hederacea is a self-compatible species whose geographic origin is contested, and previous work suggests that although there are signals of adaptation (significant leaf shape and flowering time clines), no population structure or neutral genetic differentiation of I. hederacea populations was detected. Here, we use DNA sequence data to characterize patterns of genetic variation to establish a more detailed understanding of the current and historical processes that may have generated the patterns of genetic variation in this species. We resequenced ca. 5000 bp across 7 genes for 192 individuals taken from 24 populations in North America. Our results indicate that North American I. hederacea populations are ubiquitously genetically depauperate, and patterns of nucleotide diversity are consistent with population expansion. Contrary to previous findings, we discovered significant population subdivision and isolation-by-distance, but genetic structure was spatially discontinuous, potentially implicating long-distance dispersal. We further found significant genetic differentiation at sequenced loci but nearly fourfold stronger differentiation at the leaf shape locus, strengthening evidence that the leaf shape locus is under divergent selection. We propose that North American I. hederacea has experienced a recent founder event, and/or population dynamics are best described by a metapopulation model (high turnover and dispersal), leading to low genetic diversity and a patchy genetic distribution.

Myzus persicae (Sulzer) is an efficient vector of potyviruses in sweet potato, Ipomoea batatas (L.). These potyviruses also infect members of the morning glory family Ipomoea cordatotriloba Dennstedt and Ipomoea hederacea Jacqin commonly found within or around sweet potato fields. Infection of sweet potato with potyviruses increases the intrinsic rate of increase of M. persicae. Thus, from the epidemiological stand point, virus infection can modify vector population dynamics, and therefore increase virus spread. To better understand this, stylet penetration behaviors of M. persicae on virus infected and noninfected sweet potato cvs. 'Beauregard' and 'Evangeline', as well as morning glory plants I. cordatotriloba and I. hederacea were monitored. Stylet penetration behaviors associated with nonpersistent virus transmission such as time to first intracellular puncture (potential drop), number of potential drops, duration of potential drop, duration of potential drop subphase II-3, and number of potential drops with subphase II-3 pulses were significantly increased on virus-infected compared with noninfected Beauregard, but greatly reduced on virus-infected compared with noninfected I. hederacea plants. Stylet penetration behaviors associated with host acceptance such as reduced nonprobing duration and nonprobing events were greater on virus-infected compared with noninfected Beauregard plants. In contrast, on Evangeline, I. cordatotriloba and I. hederacea stylet penetration behaviors by M. persicae indicate it had less preference for virus-infected compared with noninfected plants.

A field study was conducted in Arkansas over three years to evaluate various herbicide treatments, including sequential and tank-mix applications for weed control in grain sorghum (Sorghum bicolor). The herbicide treatments used were quinclorac, atrazine + dimethenamid-p, S-metolachlor followed by (fb) atrazine + dicamba, dimethenamid-p fb atrazine, S-metolachlor + atrazine fb atrazine, S-metolachlor + mesotrione, and S-metolachlor fb prosulfuron. All herbicide treatments provided excellent (90% to 100%) control of Ipomoea lacunosa, Ipomoea hederacea var. integriuscula, and Sida spinosa by 12 weeks after emergence. Quinclorac and S-metolachlor fb prosulfuron provided the lowest control of Ipomoea lacunosa, Urochloa platyphylla, Amaranthus palmeri, and Ipomoea hederacea var. integriuscula. Weed interference in the non-treated control reduced grain sorghum yield by 50% as compared to the weed-free control. S-metolachlor + mesotrione and S-metolachlor fb prosulfuron reduced sorghum yields by 1009 to 1121 kg ha&minus, 1 compared to other herbicide treatments. The five best herbicide treatments in terms of weed control and grain sorghum yield were quinclorac, atrazine + dimethenamid-p, S-metolachlor fb atrazine + dicamba, dimethenamid-p fb atrazine, and the standard treatment of S-metolachlor + atrazine fb atrazine.

Leaf shape is a highly variable phenotype, and is likely influenced by many sources of selection. Ipomoea hederacea exhibits an adaptive latitudinal cline in leaf shape, which is controlled by a single Mendelian locus: lobed individuals dominate the north with entire-shaped individuals mostly in the south. We test if the following candidate selective agents, suggested by the literature, are responsible for the cline: differential insect herbivory, genetic correlations with other clinal traits like flowering time and growth rate, and thermoregulatory differences. We planted 1680 F3 individuals, segregating for leaf shape, in the north of I. hederacea's range, where we expected lobed genotypes to have higher fitness. Individuals were assigned to insect removal or control treatments, and we scored herbivory, flowering time, growth rate, leaf temperature, and fitness (seed number). Herbivory, flowering, and growth rate had significant fitness effects, but none differed between leaf shapes. Lobed leaves were consistently warmer at night, but no performance advantage was detected. Finally, we detected no overall fitness differences between leaf shape genotypes, whether we controlled for other traits under selection or not. Our data suggest these candidate selective agents may not be important contributors to the cline, and alternative approaches to understanding the mechanisms maintaining the leaf shape cline in I. hederacea may be necessary.

The present investigation has been carried out to determine the proximate composition, amino acids, metal contents, oil composition as well as the antioxidant capacity of the seeds of Ipomoea hederacea Jacq. and Lepidium sativum L. Proximate composition indicated a great difference in oil (14.09 ± 0.66, 28.03 ± 1.05) and fibre (16.55 ± 0.31, 6.75 ± 1.20) contents for I. hederacea and L. sativum, respectively. Fatty acid profile indicated that oleic acid (19.50 ± 0.37, 30.50 ± 0.16) and linoleic acid (52.09 ± 0.48, 8.60 ± 0.38) are the major fatty acids. γ-Tocopherol and d-tocopherol (28.70 ± 0.14, 111.56 ± 0.37) were the most abundant in the seed oil of I. hederacea and L. sativum, respectively. Results of TEAC, FRAP and TRAP antioxidant assays indicated that L. sativum has much greater antioxidant potential than I. hederacea.

Glyphosate is the most widely used herbicide for postemergence weed control in Florida citrus (Citrus spp.). Variation in susceptibility of certain weed species to glyphosate has been observed in last few years. Therefore, understanding the mechanism underlying such phenomenon is required. Experiments were conducted to evaluate differences in tolerance of four weed species to glyphosate by quantifying glyphosate efficacy, the amount of epicuticular wax, absorption, and translocation of carbon-14-labeled glyphosate (14C glyphosate). The results of glyphosate efficacy study suggested that application of glyphosate at 3 oz/acre resulted in 99%, 90%, and 84% control of florida beggarweed (Desmodium tortuosum), spanishneedles (Bidens bipinnata), and johnsongrass (Sorghum halepense), respectively. Increasing application rate and addition of nonionic surfactant (NIS) usually did not improve glyphosate efficacy. Ivyleaf morningglory (Ipomoea hederacea) was the most tolerant and resulted in 0% and 25% control when glyphosate applied at 3 and 24 oz/acre, respectively. Biomass reduction in all weed species reflected a similar trend to percent control in response to all glyphosate treatments. Glyphosate absorption and translocation in the weed species were differed with the quantity of wax extracted. Ivyleaf morningglory had the lowest leaf wax content (10.8 μg·cm−2) and showed less absorption (62% to 79%) and translocation (15% to 39%) of 14C-glyphosate compared with other weed species. The absorption of 14C-glyphosate was in the range of 87%, 71% to 83%, and 72% to 83%; and translocation was 34% to 50%, 32% to 52%, and 53% to 58% in florida beggarweed, spanishneedles, and johnsongrass, respectively. Increasing glyphosate application rate from 6 to 12 oz/acre and addition of NIS usually increased 14C-glyphosate translocation.

A plant's best strategy for acquiring resources may often depend on the identity of neighbours. Here, I ask whether plants adjust their strategy to local relatedness: individuals may cooperate (reduce competitiveness) with kin but compete relatively intensely with non-kin. In a greenhouse experiment with Ipomoea hederacea , neighbouring siblings from the same inbred line were relatively uniform in height; groups of mixed lines, however, were increasingly variable as their mean height increased. The reproductive yield of mixed and sibling groups was similar overall, but when adjusted to a common mean height and height inequality, the yield of mixed groups was significantly less. Where this difference in yield was most pronounced (among groups that varied most in height), mixed groups tended to allocate more mass to roots than comparable sibling groups, and overall, mixed groups produced significantly fewer seeds per unit mass of roots. These results suggest that, from the group perspective, non-kin may have wasted resources in below-ground competition at the expense of reproduction; kin groups, on the other hand, displayed the relative efficiency that is expected of reduced competitiveness.

The ability of a population to respond to natural selection will be determined by the patterns of genetic variation and covariation in traits under selection. In the quantitative genetic framework, these patterns of genetic variation and covariation are described by the G matrix, which for a given pattern of selection will determine the size and direction of evolutionary responses. Several methods have been developed to evaluate the nature of evolutionary constraints imposed by G, although this multitude of methods has never been applied to a common data set to compare their strengths and weaknesses, or the similarity of evolutionary inferences they produce. Here we compare several multivariate methods that calculate genetic constraint using a quantitative genetic field study in the ivyleaf morning glory, Ipomoea hederacea. We focus on a tractable number of traits (size at flowering, final size, and flowering time), which allows us to pair multivariate quantitative methods with qualitative interpretations...

Sensitivity cycling to physical dormancy (PY) break in seeds is known to occur in some Fabaceae and Convolvulaceae species. PY in seeds of species of Convolvulaceae and of some other angiosperm plant families can be broken by storing them dry. However, the mechanism of opening the water gap in the seed coat (dormancy break) during dry storage has not been investigated. In research reported here, we determined whether sensitivity cycling occurs in seeds of Ipomoea hederacea (Convolvulaceae) and investigated the effect of dry storage on opening of the water gap. Seeds can cycle between insensitive and sensitive states to dormancy break, and dormancy can be broken in sensitive seeds by storing them dry at high to moderate temperatures. Seeds with the lower part of the hilum blocked lost a minimal amount of water during storage. Percentage water loss was significantly correlated with percentage dormancy break. Desorption of water through the hilar fissure during dry storage reduced the vapor pressure below th...