Polypogon Monspeliensis Research Articles

Some More Plants from Khedbrahma Region, North Gujarat

In this paper 49 angiospermous species - 32 dicotyledons and 17 monocotyledons are listed. Polypogon monspeliensis Desf. and Medicago polymorpha L. are recorded for the first time from Gujarat.

POLYPOGON MONSPELIENSIS FROM OLTENIA, ROMANIA

Characterised by numerous microclimates that are present from the plain area and up to the alpine region, the territory of Oltenia previously offered and still manages to offer surprises from a floristic point of view, as well as from other perspectives. The recent climate changes have altered the typical habitats of some plants, resulting in their discovery in areas where, according to the data in the specialized literature, were not previously known to exist. Among the many species of Poaceae that are present in the spontaneous flora of Oltenia, there are certain species of sozological and phytogeographical interest. This is also the case with the species presented in the current paper, i.e. Polypogon monspeliensis (L.) Desf. Polypogon monspeliensis (L.) Desf. is an Atlantic-Mediterranean coastal species, found especially on the western and southern European coastal sands. It is native to northern Africa, southern and western Europe, western and northern Asia, Japan and the Indian subcontinent (India, Nepal, Pakistan, and Sri Lanka). The species has been widely naturalized in southern and eastern Australia, in South Africa, New Zealand, Canada, the USA, Central and South America, as well as in Hawaii. In Romania, it is known from the south-eastern part of the country: Tulcea and Constanța counties. In Poiana Brașov and Vaideeni (Vâlcea County), the species is mentioned as an adventive plant. The present paper contributes with information regarding the chorology and ecology of this species.

Plants as bioindicators of heavy metal pollution

This research was designed to assess metal deposition (Zn, Cr, As, Cd, Hg and Pb) and modifications in photosynthetic pigments, total nitrogen, protein in six plant species (Brachiaria eruciformis, polypogon monspeliensis, Phragmites australis, Cynodon ductylon, Prosopis farcta and Typha domingensis)  near Turaq region which was designated as polluted site and comparing it to control site. The results indicated a significantly increased concentration of studied metals in the contaminated area. Phragmites australis shows maximum accumulation of Cr, As, and Hg. The accumulation of Zn, Pb and Cd were highest in Prosopis farcta, Cynodon ductylon and polypogon monspeliensis, respectively. Pigments and proteins were found in lower amounts in plants grown on polluted soil. Metals were negatively correlated with pigments, total nitrogen and proteins in all of the studied plants. The data demonstrated the existence of metals in the plant body in both regions, indicating that there is a variation in metal absorption capacities.

Seed Size, Not Dispersal Syndrome, Determines Potential for Spread of Ricefield Weeds by Gulls.

Recent field data suggest that migratory gulls disperse many rice field weeds by gut passage (endozoochory), most of which are dry fruited and widely assumed to have no long-distance dispersal mechanisms, except via human activity. We investigated this mechanism with a feeding experiment, in which seeds of five common rice field weeds (in order of increasing seed size: Juncus bufonius, Cyperus difformis, Polypogon monspeliensis, Amaranthus retroflexus, and the fleshy-fruited Solanum nigrum) were fed to seven individuals of lesser black-backed gulls Larus fuscus held in captivity. We quantified seed survival after collecting faeces at intervals for 33 h after ingestion, then extracting intact seeds and running germination tests, which were also conducted for control seeds. All five species showed high seed survival after gut passage, of >70%. Gut retention times averaged 2-4 h, but maxima exceeded 23 h for all species. Germinability after gut passage was 16-54%, and gut passage accelerated germination in J. bufonius and S. nigrum, but slowed it down in the other species. All species had lower germinability after gut passage compared to control seeds (likely due to stratification prior to the experiment), but the loss of germinability was higher in smaller seeds. There was no evidence that the different dispersal syndromes assigned to the five species (endozoochory, epizoochory or barochory) had any influence on our results. In contrast, mean gut retention time was strongly and positively related to seed size, likely because small seeds pass more quickly from the gizzard into the intestines. Non-classical endozoochory of dry-fruited seeds by waterbirds is a major but overlooked mechanism for potential long-distance dispersal, and more research into this process is likely essential for effective weed management.

WEEDS INFESTING WHEAT CROP IN ROHTAK, HARYANA

Multiple field visits were performed to investigate weed flora of wheat fields in Rohtak district of Haryana, conducted during 2018 which revealed infestation of 28 weed species comprising 15 families of grasses and broadleaf weeds.The weeds were identified with the help of available literature and through comparison with the already identified weed species. Poa annua, Polypogon monspeliensis and broadleaf weeds Chenopodium album, Rumex retroflex, Coronopus didymus were the pre-dominant weeds in moist region, whereas Cynodon dactylon, Fumaria parviflora, Chenopodium album,Polypogon monspeliensis in light soil with low salinity.There was a greater variety of weeds in Bohar and Kharawar villages and the least was found in village Sheria and Garnavati from vegetative to fully grown stage.Maximum number of species were of family Poaceae and Asteraceae. This study will be helpful as an additional tool in maintaining the floristic composition of District Rohtak as well as in controlling the weed problem.

Rabbit’s Foot Grass (Polypogon: Poaceae), A New Generic Record for the Telangana Flora

Rabbit’s foot grass (Polypogon monspeliensis (L.) Desf.: Poaceae) is collected from Nirmal district of Telangana in India is reported for the first time in the state. A detailed description with photographs is provided to facilitate easy identification.

Rice Paddy Soil Seedbanks Composition in a Mediterranean Wetland and the Influence of Winter Flooding

Soil seedbanks are defined in composition and quantity by many environmental factors inherent to a specific area, and they can be an indicator of the potential problems of weeds in crops. In Valencia (Spain), rice is cultivated with continuous flooding during the growing season, and after harvesting, many of the paddy fields are flooded again during the winter. This study investigates the paddy fields’ soil seedbank composition in this Mediterranean paddy area and the effect of winter flooding on the soil seedbank. Multispectral images from the Sentinel-2 satellite were used to characterise the water level of paddies in winter. Satellite images facilitated the characterisation of winter flooding in fields. Soil samples from sixty-nine points distributed over 15,000 ha of paddies were used to determine the composition of the seedbank plots. The data were spatially represented by geographic information systems. The species that contributed most to the paddy seedbank were Cyperus difformis L., an important rice weed in the Mediterranean area, and other rice weeds such as Echinochloa sp. and Leptochloa fusca subspecies. Other species with a great contribution to the seedbank are species that develop in paddy fields that produce a large quantity of small seeds, such as Lemna sp., Polypogon monspeliensis (L.) Desf., and Nasturtium officinale R. Br. These species interfere little or do not interfere with the rice crop. The study revealed that in general, flooding reduced seedbank density with differences between species. Furthermore, the influence of winter flooding on the different plant species obtained as well as their distribution maps are a further step in this protected area from the point of view of weed management in rice crop, as well as in the management of this Mediterranean wetland.

MORPHOLOGICAL STUDY OF POLYPOGON MONSPELIENSIS (L.) DESF., A COMMON KITCHENGARDEN GRASS OF CHOUPARAN, HAZARIBAG, JHARKHAND

Polypogon monspeliensis (L.) Desf. is a common kitchen garden grass belonging to the family Poaceae/ Gramineae (Bor, 1960). In English, it is known as annual beard-grass or rabbitsfoot grass (Hooker, 1896). It is commonly found in Chouparan Block of Hazaribag District, falls under Jharkhand state of India (Singh et al. 2001). It started owering in spring season. The inorescence is so smooth and greenish in colour (see photographs). It is a common weed. In initial stage, the inorescence is not splitted but on maturity it get splitted.

Assessment of Phytoremediation Potential of Seven Weed Plants Growing in Chromium- and Nickel-Contaminated Soil

A pot experiment was conducted to evaluate the phytoremediation efficacies of seven weed plant species, viz., Bidens pilosa L., Chenopodium album L., Malvastrum coromandelianum L., Garcke, Oxalis corniculata L., Parthenium hysterophorus L. (an invasive species), Polypogon monspeliensis L., and Rumex dentatus L., against heavy metals like chromium (Cr) and Nickel (Ni). These metals were administered in dose ranges from 10 to 40 mg CrNO3 and 10 to 50 mg NiNO3 kg–1 soil. Biochemical parameters like total chlorophyll, carotenoids, protein, and proline contents were measured against metal stress. Uptake parameters, viz., bioconcentration factor (BCF), bioaccumulation coefficient (BAC), and translocation factor (TF), were also evaluated. Remediation potential of experimental plants was judged based on tolerance index (TI). All plants, when treated with Ni10–20 and Cr10 enhanced total chlorophyll and carotenoid contents. Increase in contamination and enrichment ratio caused a toxic response to plants up to some extent. Ni and Cr stress decreased the protein content and increased proline content in a concentration-dependent manner. Plant species invariably showed high TI at the lowest dose and low TI at higher doses of both heavy metals. A significant increase in Cr and Ni accumulation, coupled with a high bioaccumulation coefficient, in roots and shoots of all seven species was observed as a response to Cr and Ni stress.

Spatial patterns of weed dispersal by wintering gulls within and beyond an agricultural landscape

Abstract Non‐frugivorous waterbirds disperse a wide variety of plants by endozoochory, providing longer‐dispersal distances than other mechanisms. Many waterbirds visit both agricultural and natural landscapes during their daily movements, but potential bird‐mediated dispersal of weed plants within and from agricultural landscapes to other habitats is commonly overlooked. Gulls (Laridae) are expanding in numbers and increasingly exploiting anthropogenic habitats worldwide, with possible growing implications for the spread of weeds. Yet, to date, there are no studies on the spatial distribution of weed dispersal by waterbirds. We developed a plant dispersal model based on movements of 19 Larus fuscus using ricefields, via GPS telemetry. We combined daily movements with two curves estimating the retention times of plant seeds in their guts: (a) an experimental curve based on retention time in captivity for four weeds with dry fruits known to be dispersed by gulls: Juncus bufonius, Cyperus difformis, Polypogon monspeliensis and the alien Amaranthus retroflexus; (b) a theoretical curve based on the interspecific scaling relationship between body mass and mean retention time. Median dispersal distances of weed plant seeds by gulls ranged between 690 and 940 m, but maximum distances exceeded 150 km. The theoretical retention time model showed higher median dispersal distances than the experimental retention time model. Spatial patterns of weed deposition were very similar between retention time methods, and most strongly depended on gull movements. Variation between individual gulls had little influence on seed shadows. About 92% of all seeds (>10,000 intact seeds per day) were dispersed within the ricefield area of 370 km2. The remaining 8% of seeds were deposited beyond ricefields into other habitats, 42% of which reached moist environments (other irrigated agriculture, rivers and natural wetlands) presumably suitable for weed establishment. Synthesis. Gulls can disperse weed plants over long distances across a mosaic of habitats. This implies exchange of weed plant species between human‐dominated and natural areas by waterbirds as dispersal vectors. This spatial study highlights the importance of non‐frugivorous birds for long‐distance plant dispersal, which is generally an overlooked mechanism in studies aiming to predict and manage expansion of weed plants.

Germination response of four Arabian desert grasses to low water potential

Species that can germinate under low water potential are likely to have greater utility for fodder production and restoration in arid habitats. We investigated seed germination response of four native grass species (Panicum acuminatum, Panicum turgidum, Pennisetum divisum and Polypogon monspeliensis) to five osmotic potentials (0, −0.3, −0.6, −0.9 and −1.2 MPa) using polyethylene glycol‐6000 and two light treatments (0, 12 h light per day). All the studied species exhibited high germination (> 77%) at ψ = 0 MPa except P. turgidum (42%). Polypogon monspeliensis seeds did not show any significant reduction in germination from ψ = 0 to −0.3 MPa (90–83%), but all other species did, averaging from 75.8 to 60.5%. At ψ = −0.6 MPa seed germination was reduced to around 20%. Germination of most species was unaffected by light, but P. divisum seeds that germinated in darkness were more tolerant to water deficit. Reduction of water potential to −0.3 MPa inhibited the germination timing for P. acuminatum (ca 1.69 days difference to 50% germination [t50]), P. divisum (ca 1.56 day) and P. monspeliensis (ca 1.14 days). Germination of P. acuminatum and P. monspeliensis were similar after stressful exposure to all osmotic potentials, while for P. divisum there was reduced germination (85% at −0.6 MPa to 58% −1.2 MPa), indicating a dormancy induction. Tolerance to low water potentials, and response after release from these low potentials, indicates the species are adapted to survive in drier environments.

Phytotoxic effect of herbicides on gladiolus and their effectiveness against weed flora associated with the crop

The present investigation was conducted during 2018-19 at Centre for Quality Planting Material, RDS Seed Farm CCSHAU, Hisar, Haryana. The experiment comprised of 16 treatments i.e. nine herbicidal treatments [viz. oxyfluorfen @ 500 g ha-1, pendimethalin @ 1000 g ha-1, butachlor @ 1000 g ha-1, carfentrazone @ 30 g ha-1 and metsulfuron-methyl @ 5 g ha-1 in combinations of pre and pre/post-emergence application at 50 DOP (days of planting) after the HW (hand weeding) or without HW], five mulch treatments (viz. mulching of black polyethylene sheet of 100 µ alone, and the paddy straw mulching @ 10 tonnes ha-1 in combinations with HW at 75 DOP or pre-emergence application of pendimethalin @ 1000, 1250 & 1500 g ha-1), and one treatment of hand weeding/hoeing (at 25, 50 & 75 DOP), and weedy check (control), laid out in simple randomized block design with three replications. Polypogon monspeliensis, Phalaris minor, Cyperus rotundus and Cynodon dactylon among monocots and Chenopodium murale, Convolvulus arvensis, Fumaria parviflora and Coronopus didymus in dicots were found dominant weeds in experimental field. Among the application of herbicides or mulch materials either alone or in combinations, black polyethylene mulch (T13) was found highly effective in controlling weeds followed by pendimethalin 1000 g fb HW + pendimethalin 1000 g (T12), straw mulch fb HW at 75 DOP (T14) and pendimethalin 1500 g/ha + straw mulch (T6). Amongst the herbicidal treatments, pendimethalin 1000 g fb HW + pendimethalin 1000 g (T12) was found comparatively more efficient in controlling weeds without any phytotoxic effect on crop. Interestingly, the applications of oxyfluorfen as a pre-emergence and metsulfuron-methyl as a post-emergence in different herbicidal combinations caused phytotoxicity in crop plants up to the level of growth check or one leaf burning, and the phytotoxic effect of metsulfuron-methyl was more than the oxyfluorfen. At 30 DOP the maximum level of phytotoxicity (1.70) was recorded with the pre-emergence application of oxyflurofen 500 g fb HW + oxyflurofen 500 g (T3), while at 60 DOP it was observed non-significant with most of the herbicidal applications, whereas at 90 DOP and 120 DOP, it was recorded highest (i.e. 2.73 and 2.97, respectively) with the application of oxyfluorfen 500 g fb metsulfuron-methyl 5 g (T2) and it was followed by post-emergence application of metsulfuron-methyl 5 g in combinations with pre-emergence application of other herbicides (T8 & T11). Overall, the application of mulch materials (either alone as a black polyethylene sheet of 100µ or paddy straw @ 10 tonnes ha-1 in the combination with HW or pendimethalin 1500 g ha-1) was found very effective with the aspect of weed control in gladiolus.

Pesticidal activity of Solanum elaeagnifolium Cav. Leaves against nematodes and perennial weeds

Sliver nightshade (Solanum elaeagnifolium Cav.) an invasive weed species in cultivated lands of Egypt threatens native and crop species. The allelopathic potential of this weed was assessed against nematode and weeds. The aqueous extracts of Sliver nightshade leaves and seeds exhibited strong impacts in root knot nematode Meloidogyne incognita galls, egg-masses, female's numbers and juveniles' number. The incorporate dried leaves of S. elaeagnifolium with soil positively affected M. incognita infection and enhanced Eggplant Solanum melongena cv. white Balady growth traits under the greenhouse proportional to concentration. The allelopathy of aqueous extracts negatively influenced Convolvulus arvensis, Polypogon monspeliensis, Phalaris minor and Triticum aestivum germination and growth. Bioassay and spectroscopic instruments guided to four active flavonoids; hydroxyl −3-methoxyflavone, quercetin, kaempferol 3β-D-(6”-O-cis-cinnamoyl glucoside) and chlorogenic acid on Convolvulus arvensis and Arabidopsis thaliana weeds total biomass. These findings proved the importance of invasive weeds allelochemicals to be considered as a source of natural pesticides into agricultural systems.

Fate of mercury in a terrestrial biological lab process using Polypogon monspeliensis and Cyperus odoratus

Mercury has been extracted in Queretaro, Mexico since the 1960s. The mining wastes were open-air disposal and these mercury wastes have polluted the zone. The aim of this research was to evaluate mercury's fate in lab scale terrestrial reactors considering the following mercury species: soluble, interchangeable, strongly bound, organic, and residual ones. Soils were sampled in two former mines of Pinal de Amoles, Queretaro, Mexico (N 20° 58′ to 21° 21′ and West 99° 26′ to 99° 43′) with initial mercury concentrations were 424 ± 29 and 433 ± 12 mg kg−1 for “La Lorena” and “San Jose” former mines, respectively. Two vegetal species Polypogon monspeliensis and Cyperus odoratus were used and 20 reactors were constructed for the lab process. Total mercury was removed to 49–79% from both soils. Mercury elemental, exchangeable, and organic species had the most removal or exchange in the process. Metal uptake, by the plants, was of 5–6% for P. monspeliensis and 5–15% for C. odoratus. Also, mercury fate was estimated to the atmosphere to be 3.3–4.5 mg m−2 h−1 for both soils.

Competitiveness of generalist plant populations at a mine site

Plants inhabiting extremely stressful mine site environments tend to be specialized and localized, where they express lower performance than nonmine site plants from adjacent areas. However, such a cost may be concealed. In a previous study at a mine site, we found mine and adjacent nonmine plants of multiple species expressed similar performances in the absence of competition. However, a lower competitive ability may be a concealed driver. We aim to test whether costs under competition could explain specialization. In a glasshouse experiment, we measured the performance (i.e. vegetative and reproductive growth) of mine and nonmine potted plants under competition. The 6 herbaceous species tested were Anagallis arvensis L., Cirsium vulgare (Savi) Ten., Conyza sumatrensis Retz., Echium vulgare L., Oxalis chnoodes Lourteig, and Senecio diaschides D.G.Drury. We exposed individuals to interspecific competition using a local grass (Polypogon monspeliensis), as well as to intraspecific competition. Plants were grown alone for the control group. For all treatments, the mine plants expressed similar performances to the nonmine plants, except for mine site O. chnoodes, which had lower performance under intraspecific competition. Mine plants of A. arvensis and C. sumatrensis had higher performance than nonmine plants. Overall, there was no evidence of specialization in the mine site plants. These results indicate that, under some circumstances, inhabiting a stressful metal habitat does not promote specialization in multiple species. Future research may focus on assessing the environmental conditions and population genetics that promote the evolution of generalists that inhabit extremely stressful environments.

Winter weeds and its control in the medicinal plants in Egypt: a survey study

Weed control is the main obstacle in the production of medicinal plants, especially in organic farming where the growers cannot use synthetic herbicides. For understanding the impact of weeds on the productivity of medicinal plants, the common weeds and weed control practices of more than 20 cultivated medicinal plants were evaluated in eight regions in Egypt with several of climatic conditions and soil types. All tested farms that have applied the organic farming systems and their products are mainly for export. The large-scale weed surveys have shown that the most problematic weed species in medicinal plant crops is Senecio desfontainei because it is content of pyrrolizidine alkaloid plants. The dominant weeds associated with the medicinal plant fields were Malva parviflora (16.8%), Chenopodium album (12.4%), Medicago intertexta (8.8%), Anagallis arvensis (8.8%), Sonchus oleraceus (6.2%), Beta vulgaris (5.3%) Brassica kaber (5.3%), Cichorium pumilum (3.5%), Melilotus indica (3.5%), Euphorbia geniculata (3.5%), S. desfontainei (1.8%), Emex spinosus (0.9), Solanium nigrum (0.9%), and Conyza linifolia (0.9%). The narrow-leaf weeds are Lolium multiflorum (7.1%), Avena fatua (6.2%), Phalaris minor (2.7%), and Polypogon monspeliensis (1.0%). The perennial broad-leaf and narrow-leaf weeds were Convolvulus arvensis (3.5%) and Cyperus rotundus (0.9%). The results of the survey indicated that the crop type and location had a significant effect on weed species and their frequencies and abundances. The common practice for weed control in the medicinal plants is hand weeding, mulch, acetic acid, presowing false irrigation, and mechanical weeding (in limited area). The efforts must be taken regarding search for safe, new, and nontraditional weed control methods to apply in the medicinal plant fields.

Changes in weed species composition in irrigated agriculture in Saharan Algeria

SummaryThis work characterises the changes in composition of the weed flora commonly associated with certain south‐eastern Algerian crops over a 20‐year period. Vegetation sampling was carried out between 1990 and 2010 in three 1 ha date palm plantations that do not have understory crops, six 400 m² glasshouses used for market gardening and three 30 ha cereal centre‐pivot irrigation plots. In total, 162 species belonging to 40 families were recorded. As in many other agroecosystems around the world, the dominant families were Poaceae, Asteraceae, Brassicaceae and Amaranthaceae representing 45.1% of the species identified. The weed communities were characterised by a set of species from various origins: species with biregional, triregional and multiregional origins, and Saharo‐Arabian and Mediterranean species were particularly well represented. Overall, the most common weed species were as follows: Chenopodium murale, Lolium multiflorum, Melilotus indicus, Lysimachia arvensis, Sonchus oleraceus, Setaria verticillata, Polypogon monspeliensis and Erigeron canadensis, all of which are therophytes. The weed flora differed among the three sampled agroecosystems, which is to be expected, as their respective management sequences are quite different. Weed monitoring over the 20 years showed that weed composition changed over time, particularly in the palm plantations and the cereal plots. For a better understanding of the drivers of weed composition and changes over time and better weed management, studying weed provenance (crop seed purchase and organic fertilisation) as well as agricultural practices is necessary.

Physiological responses of Polypogon monspeliensis L. in petroleum-contaminated soils.

In a greenhouse study, decontamination capacity of the species Polypogon monspoliensis was investigatedfor detoxification of petroleum-polluted soils caused by sewage and waste materials of Tehran Petroleum Refinery. For this purpose, the amount of total oil and grease before and 45 days after transplanting one-month-old seedlings in the soils of five different treatments were measured. Pollution-free agricultural soil and contaminated soil were mixed together with the weight ratios of 1 to 9 (%10), 2 to 8 (%20), 3 to 7 (%30), 4 to 6 (%40), and 5 to 5 (%50). These were then compared with the amounts obtained from control treatment without vegetation, but with the same concentration of pollution. Findings demonstrated that the maximum reduction in the petroleum rate (84.85%) was related to the treatment of 10% contamination containing the plant. Increase in the shoot height in treatments 10% and 20% as well as the root dry and fresh weight in treatments 10% , 20% , and 30% shows that probably activity of more rhizosphere microorganisms of the plant in these treatments has led to the improvement in the growth of plant organs comparing to the treatments without pollution.

Non‐cultivated grass hosts of yellow dwarf viruses in Ethiopia and their epidemiological consequences on cultivated cereals

AbstractThe yellow dwarf (YD) disease complex epidemics in cultivated cereals grown in a specific period of the year mainly depend on the presence of potential reservoir alternative hosts harbouring both the viruses and the vectors over the off‐season and serve as a source of inoculum in subsequent cropping season, further spread being supported by efficient aphid vectors. As such, an extensive and intensive exploration to generate base line information on the identity and prevalence of YD viruses [barley yellow dwarf virus (BYDV)‐PAV, BYDV‐MAV and BYDV‐SGV; cereal yellow dwarf virus (CYDV)‐RPV; and maize yellow dwarf virus (MYDV)‐RMV] on wild annual and perennial grasses and forage cereals alternative hosts was conducted consecutively during 2013–2015 main‐ and short‐rainy seasons in cereals growing belts of Ethiopia. Random sampling was employed to collect the samples that were tested by the tissue blot immunoassay (TBIA) to identify the YDVs associated with the hosts using a battery of virus‐specific polyclonal antibodies. Of 13,604 samples analysed, YDVs were detected in 392 (2.9%) samples, which consisted of various wild grasses, forage cereals and three cultivated crops. YDVs were identified from at least 26 grass species and forage cereals, some of them are new records, and some are previously documented hosts. To our knowledge, this is the first report of YDV infection of Andropogon abyssinicus (FresenR.Br. ex Fresen.) (BYDV‐PAV), Avena abyssinica Hochst (BYDV‐PAV), Bromus pectinatus Thunb. (BYDV‐PAV and BYDV‐MAV), Eragrostis tef (Zuccagni) Trotter (BYDV‐PAV), Eragrostis sp. (BYDV‐PAV), Hyparrhenia anthistrioides Stapf. (BYDV‐PAV), Panicum coloratum L. (BYDV‐PAV), Polypogon monspeliensis (L.) Desf. (BYDV‐PAV), Setaria pumila (Poir.) Roem & Schult (BYDV‐PAV, BYDV‐SGV and MYDV‐RMV), Setaria australiensis (Scribn. & Merrill) Vickery (BYDV‐PAV, BYDV‐MAV and CYDV‐RPV) and Snowdenia polystachya (Fresen.) Pilg (BYDV‐PAV, BYDV‐MAV, BYDV‐SGV, CYDV‐RPV and MYDV‐RMV).

Pollen-mediated gene flow from transgenic perennial creeping bentgrass and hybridization at the landscape level.

The planting of 162 ha of transgenic glyphosate-resistant creeping bentgrass (Agrostis stolonifera) near Madras, OR, USA, allowed a unique opportunity to study gene flow over time from a perennial outcrossing species at the landscape level. While conducting a four year in situ survey, we collected panicles and leaf tissue samples from creeping bentgrass and its sexually compatible species. Seeds from the panicles were planted, and seedlings were tested in the greenhouse for expression of the transgene. Gene flow via pollen was found in all four years, at frequencies of 0.004 to 2.805%. Chloroplast markers, in combination with internal transcribed spacer nuclear sequence analysis, were used to aid in identification of transgenic interspecific and intergeneric hybrid seedlings found during the testing and of established plants that could not be positively identified in the field. Interspecific transgenic hybrids produced on redtop (Agrostis gigantea) plants in situ were identified three of the four years and one intergeneric transgenic creeping bentgrass x rabbitfoot grass (Polypogon monspeliensis) hybrid was identified in 2005. In addition, we confirmed a non-transgenic creeping bentgrass x redtop hybrid in situ, demonstrating that interspecific hybrids have established in the environment outside production fields. Results of this study should be considered for deregulation of transgenic events, studies of population dynamics, and prediction of gene flow in the environment.