Brief Summary of Minutes of Annual Meeting

Objective 1. Fill critical knowledge gaps in our understanding of the biology, ecology, and impact of annual bluegrass weevil (ABW) and anthracnose associated with annual bluegrass on golf courses in the Northeast and Mid-Atlantic. In the area of impact, a survey for anthracnose and ABW was developed and made available to golf course superintendents in the U.S. and Canada via the World Wide Web (Hsiang, Kaminski). A total of 313 turfgrass professionals participated in the survey to date. Of the participants, 71 and 46% stated that they have had troubles with anthracnose or ABW, respectively. For anthracnose, participants estimated that they spent d$20,000 (48%), between $20,000-40,000 (31%), or e$40,000 (18%) on fungicides specifically targeting this disease. Near half of the respondents (49%) stated that the total dollars spent managing anthracnose accounted for e20% of their total fungicide budget. A total of 31 participants stated that they spent e50% of their total fungicide budget on anthracnose control. Of the survey participants, 85% stated that they spent d$20,000 for control of all insects on their golf course. For ABW control, 39% estimated that >10% of their total insecticide budget was used specifically to control this insect, and 6% of the respondents spent >50% of their budget controlling ABW. Based on responses, the most severe damage was observed along the edges of fairways and the turf surrounding collars and approaches of the golf course putting greens. Moderate to severe damage to golf course putting greens was observed by approximately 17% of respondents. In the area of geographic distribution, 30 isolates of C. cereale were collected from a single P. annua putting green in NC and were submitted to Rutgers (Hillman) for inclusion in their study of C. cereale population structure (Tredway). Fifty-two isolates of C. cereale from 10 locations were tested for their sensitivity to benzimidazole and QoI fungicides in vitro. All isolates were insensitive to 10 ppm of the benzimidazole fungicide thiophanate-methyl. Mycelial growth of 48 isolates was uninhibited by 8 ppm of azoxystrobin, which is indicative of the G143L mutation that confers complete insensitivity to the QoI fungicides. Four isolates were completely inhibited by 8 ppm but were not inhibited by 0.3 ppm. These isolates may possess the F129L mutation that confers partial insensitivity. Further investigation is needed to confirm which mutations are present in the sample population. Our conclusion is that benzimidazole and QoI resistance is widespread in NC, VA and TN populations of C. cereale (Tredway). Isolates of C. cereale were collected from golf courses in New England and submitted to Rutgers for further genetic analyses (Kaminski). Reports on ABW occurrence were gathered from USGA agronomists active in the Mid-Atlantic region, which represents the southern boundary of known ABW occurrence (Shrewsbury). ABW infestations were reported from localities that include Annapolis, Baltimore, Edgewater, Park Heights and Towson, MD; Berkeley Springs and Morgantown, WV; and Washington D.C. In the area of overwintering and reproductive biology, results were fully analyzed from a series of studies designed to identify factors that influence ABW overwintering site selection and to document the nature of flux between overwintering and developmental sites (Peck). Surveys of natural populations were conducted early spring over 2 yr to test how abundance of overwintered adults depends on microhabitat and distance from developmental habitat. The influence of microhabitat on overwintering preference and success was further tested in a multiple choice and no-choice field experiment by relocating overwintering weevils into experimental arenas where 4 microhabitats were presented together or singly. The timing and direction of dispersal by walking adults was assessed using paired linear pitfall traps. Results showed that adults could overwinter e60 m from the fairway 10 m into the woods. They were most abundant near the tree line; none were detected within 5 m of the fairway. Microhabitat had a significant effect on abundance in 1 yr, being highest in mixed tree litter followed by moss, high-cut grass, and pine litter. Under multiple choice conditions, high-cut grass was preferred over low-cut grass and leaf litter, followed by pine litter. Pitfall trap captures showed a peak of activity in the spring, and at one site this was directional toward the fairway. There was no directionality or increase in activity in the fall. Based on these results, a new conceptual model of flux between habitats was proposed based on orientation of flying adults to defined tree lines in the fall. Defining this behavior will strengthen our ability to target control tactics in space and time. In the area of population biology and ecology, questions have been addressed at several levels. In FIrst, the evolutionary relationship of C. cereale to other species of Colletotrichum associated with grasses was investigated (Clarke, Crouch, Hillman). An analysis of 147 strains of Colletotrichum isolated from 45 grass species from 12 countries (61 isolates from C4 and 86 samples from C3 grasses) was performed from a four-gene, 3,400 nucleotide sequence dataset. We determined that this morphologically similar group of organisms is actually quite diverse on the molecular level, and has evolved in a pattern suggestive of ecological speciation, likely driven by host plant specialization. Although the results suggest sympatric speciation, the data are insufficient to exclude the possibility of initial allopatric segregation and subsequent dispersal. There is a clear difference between the highly specialized species that are pathogens of C4 grasses, and the lineages of C. cereale found on C3 grasses, both on turf and non-turf hosts. The grass-inhabiting Colletotrichum group has evolved along a distinct trajectory, with the earliest species adapted to non-grasses, then moving onto C4 hosts, and finally onto C3 grasses (C. cereale), with the most closely related C3- and C4-infecting lineages separated by ~41 million years of divergence. The C. cereale lineage is subdivided into nine subpopulations that correspond to lifestyle (turfgrass pathogen vs. non-turf pathogen); 89% of the pathogenic isolates from turf are members of only three populations. Thus, C. cereale may be currently undergoing ecological specialization leading to speciation, but the data provided strong evidence in support of gene flow between the subgroups. Five new species of grass-inhabiting Colletotrichum have been identified from this research. A manuscript detailing these results is in preparation (Clarke, Crouch, Hillman). Second, an examination of the C. cereale mating-type gene clusters was conducted, focusing on sexuality in the graminicolous species of Colletotrichum (Clarke, Crouch, Hillman). In order to explore the mating strategy of C. cereale, we cloned and characterized the entire ~30-kb MAT gene cluster and compared it to 10 additional grass-associated species of Colletotrichum. Using a combination of transposon-mediated cosmid sequencing, cosmid chromosome walking and PCR amplification, 8 genes were identified at the Colletotrichum MAT locus. Locus organization was identical in the grass-inhabiting Colletotrichum group, irrespective of homothallism (e.g. C. falcatum) or heterothallism (e.g. C. graminicola), with no evidence for a MAT1-1 idiomorph. Comparison of the Colletotrichum MAT gene cluster with homologous sequences of 10 ascomycetes whose genomes have been sequenced, showed that both gene composition and order has been broadly conserved in this region across evolutionary time, although several differences in gene length, as well as insertions, deletions and inversions were detected. An examination of polymorphism, divergence and selection pressures on the locus are near completion, and a manuscript describing this research is in preparation (Clarke, Crouch, Hillman). Third, an analysis of C. cereale population biology through the use of transposable genetic elements was completed and a manuscript is in review (Clarke, Crouch, Hillman). For fungi, repeat-induced point mutation (RIP) silencing minimizes the deleterious effects of transposons by mutating multicopy DNA during meiosis. In this study we identified five transposon species from the mitosporic fungus C. cereale and reported the signature pattern of RIP acting in a lineage-specific manner on 21 of 35 unique transposon loci, providing the first evidence for sexual recombination for this species. Sequence analysis of genomic populations of the retrotransposon Ccret2 showed repeated rounds of RIP mutation acting on different copies of the element. In the RIPped Ccret2 population, there were multiple inferences of incongruence primarily attributed to RIP-induced homoplasy. These results provide an initial picture of the transposon diversity of C. cereale, both within a single genome and between lineages, and highlight the potential for intragenomic populations of transposable elements to expand our understanding of fungal evolution. Fourth an investigation into the potential for recombination in populations of C. cereale using transposons was recently completed and is in review (Clarke, Crouch, Hillman, Uddin). We investigated how four repeat-induced point (RIP) mutated transposons, in conjunction with multi-locus phylogenetic analysis of non-repetitive sequence data, can be used to detect recombination and population structure from isolates representing both of the major C. cereale lineages. Low but significant levels of linkage disequilibrium, combined with reticulate network topologies, high genotypic diversity, and high levels of incompatible loci failed to support the presumption of strict clonality for C. cereale. These observations lend credence to a hypothesis suggesting that a sexual stage played an important role in the recent evolution of this pathogen. Results were fully analyzed from a 3-yr study designed to develop an understanding of the spatial and temporal association of ABW with golf course landscapes (Peck). Patterns of variation in certain population parameters were described across site, year and management habitat. In weekly surveys along fairway transects, larvae were sampled by soil core extraction and adults by hand collection. Five instars were confirmed based on head capsule width measurements; there was no overlap among instars despite certain differences in size among sites and years. Sex ratio was significantly male-skewed on the intermediate rough (1.55) and rough (1.57) versus the fairway (0.98). Insect load, a measure of population size based on cumulative insect-days, varied from 3.0- to 18.5-fold across sites and years, and averaged 8.7- and 8.0-fold greater on the fairway than rough for larvae and adults, respectively. Visual assessment of stage-specific population fluctuation curves revealed no divergence in adult males and females. Variation was greater by year than by site in terms of overall shape of the fluctuation curves, relative abundance of overwintered to spring and summer adults, population synchrony and number of generations (2-3). Evidence of bimodal spring generations demonstrated that early season population synchrony may be linked to the pattern of adults transitioning from overwintering to developmental habitats. These results are meaningful in establishing patterns of variation in seasonal dynamics across the geographic range where ABW occur as pests. In addition, the results offer prospects for assessing how phenology might be better predicted to improve the targeting of controls in space and time. In a second study, the seasonal dynamics of ABW were observed across fairway transects on three golf courses in northern and central NJ from April to October 2006 (Koppenhöfer). Two generations of ABW were documented at two sites while three generations were documented at the third. Sampling of roughs and leaf litter adjacent to infested fairways revealed that the adults from populations experiencing two generations migrated to overwintering sites in the first week of August. In a third study, the seasonal dynamics of entomopathogenic nematodes (EPN) were studied in tandem with their insect host (Koppenhöfer). ABW from all three populations were infected. The generational mortality caused by EPNs was similar between sites although ABW phenology and relative abundance differed. EPNs were observed infecting all stages between 3rd instar and pupae, although 4th and 5th instars were infected most often. The vast majority of infections occurred during the first generation of larvae, when densities were highest. Both Steinernema carpocapsae and Heterorhabditis bacteriophora infected ABW at all three sites. No other EPN species has been detected in the soils thus far. EPN populations proved to be highly variable in relative density between sampling dates and sites, yet consistently varying with the season on an annual basis. EPN peak densities correlated with the increase in first generation in the soil (4th instar to pupae). Drastic declines in EPN densities were observed during July (second generation) when densities of ABW in the soil were low (relative to the first generation) and soil temperatures increased. Objective 2. Identify and develop new cultural, biological, chemical, and genetic control options for suppressing ABW and anthracnose on golf courses. In the area of new chemical control options, a field efficacy trial was conducted in NJ to evaluate the influence of conventional fungicides and biorational products on anthracnose on a P. annua putting green (Clarke). Disease pressure was very high throughout the study (32-98% turf area infested with C. cereale on untreated turf). Only chlorothalonil (76 g a.i. 90 m-2) and tebuconazole (10.6 g a.i. 90 m-2) provided acceptable disease control (>90% control) during the test (28 June  17 August 2006). Thiophanate-methyl, propiconazole, and the QoIs azoxystrobin, fluoxastrobin, and pyraclostrobin were ineffective (not commercially acceptable) in suppressing anthracnose (0-79% control) when applied at standard label rates. Fosetyl- Al, polyoxin-D, Alude (mono- and di-potassium salts of phosphorous acid or potassium phosphite), iprodione, fludioxonil, and a tank mixture of chlorothalonil (42 g a.i. 90 m-2) + a biorational product (an experimental mixture of several N, P, K and Si sources) suppressed anthracnose early in the epidemic (91, 87, 85, 80, 78 and 96% control, respectively, from 28 June -18 July), but were less effective when disease severity increased from 27 July  17 August. The microbial fungicides B. subtilus (Rhapsody) and Bacillus licheniformis (Ecoguard) did not provide acceptable levels of disease suppression (0-59% control) during the study. A field efficacy trial was conducted in CT to evaluate the influence of existing and experimental fungicides on anthracnose on P. annua (Kaminski). Anthracnose pressure was severe in the study and 50% of untreated plots were damaged by the disease. Excellent control (d5% disease) was provided by tebuconazole, chlorothalonil and a fungicide program incorporating various products throughout the season. Good control was observed within plots treated with fludioxinil + fosetyl-Al. Thiophanate-methyl, propiconazole, Alude, and pyraclostrobin were unable to provide commercially acceptable levels of control (0-48% control). To generate research space to conduct future anthracnose studies, approximately 18,000 sq ft of putting green turf was constructed using core aerification plugs and/or sod from golf courses. Putting green turf will be available for field evaluations in 2007. The phosphonate fungicides fosetyl-Al and potassium phosphite were evaluated for preventative control of anthracnose in creeping bentgrass (A. stolonifera) and P. annua putting greens (Tredway). Trials were conducted in Raleigh, NC on Dominant creeping bentgrass and in Blowing Rock, NC on P. annua putting greens. Applications were initiated early June and repeated on 14-day intervals through late August. The incidence and severity of anthracnose basal rot or anthracnose foliar blight were evaluated on 14-day intervals prior to each application. On bentgrass, fosetyl-Al (Chipco Signature, 4 oz/1000 ft2) gave moderate suppression of disease, but potassium phosphite (Alude, 6 fl oz/1000 ft2) provided none. On P. annua, both fosetyl-Al and potassium phosphite provided moderate suppression. Based on 2 yr of experimentation, fosetyl-Al and potassium phosphite products provide good to excellent control of anthracnose diseases in P. annua, while only fosetyl-Al is effective in creeping bentgrass. An efficacy trial was conducted in PA with various phosphonate fungicides (fosetyl-Al and potassium phosphite products) on anthracnose basal rot and quality of a mixed P. annua/creeping bentgrass putting green (Landschoot). Only fosetyl-Al (Chipco Signature) and reagent-grade phosphorous acid/potassium hydroxide reduced anthracnose severity relative to the untreated control. Phosphonate fungicides and a reagent-grade phosphorous acid/potassium hydroxide treatment typically provided better turfgrass quality than untreated turf. Attempts were made to induce anthracnose on the creeping bentgrass/ P. annua research green at the Guelph Turfgrass Institute, but no disease was observed (Hsiang). A better protocol is needed for disease induction in order to be able to study this disease in the field under controlled conditions. A study initiated in 2005 to evaluate growth regulation strategies that reduce seedhead formation in the spring (mefluidide or ethephon), suppress vegetative growth (trinexapac-ethyl) throughout the season, or combine both forms of suppression on anthracnose development was continued in 2006 on a P. annua green in NJ (Clarke, Inguagiato, Murphy). Although trinexapac-ethyl (TE) did not affect anthracnose severity in the first year, it reduced disease in 2006 at rates ranging from 0.32-0.64 L ha-1 applied every 7 or 14 days. Turf incurred 29-60% less anthracnose when treated with TE than untreated turf. More frequent application of TE (i.e., 7 vs. 14 days) reduced disease on 3 and 21 July 2006 at both 0.40 and 0.64 L ha-1. There was no interaction between application interval and rate of TE. The average mefluidide (ME) treatment effect reduced anthracnose 14-39% relative to untreated turf in 2006, whereas ME-alone had 19-71% more disease compared to combinations of ME and TE. The use of ME or ethephon (ET) with repeated TE applications provided improved disease control. ME+TE reduced disease 29 and 42% on 23 June and 3 July 2006 compared to TE alone. The average ET treatment effect reduced anthracnose 24-77% relative to untreated turf on all but one date in 2006. ET+TE reduced disease compared to either growth regulator alone on 3 July 2006, and provided better control of anthracnose than ET alone on 21 July 2006. The average ET treatment had less disease than turf treated with ME in 2006. A variety of field trials were conducted across the region in 2006 to test a range of chemical and biological insecticides for suppressing ABW populations on golf course turf. In CT, two attempts were made to conduct efficacy trials on a course with a population known to be resistant to pyrethroids, but these were abandoned due to flooding and low populations (Cowles). In RI, trials on a golf course fairway were unsuccessful for the same reasons (Alm). In MA, efficacy trials were conducted on registered conventional and biorational products and one experimental product (chlorantraniliprole) (Vittum). Applications in early spring (after Forsythia full bloom but before dogwood full bloom) targeted adults and those in late spring (late May) targeted larvae. All sites were sampled in early June and some were resampled in early July to determine whether any products could reduce larval populations for more than one generation. Heavy rains compromised results at some sites. A combination product of imidacloprid and bifenthrin applied early spring reduced populations when sampled in early June but not early July. Split applications (April and early June) of the same product reduced populations when sampled in July (second generation). Among several curative products applied late spring, spinosad provided >75% control at all rates tested. In comparison, the more traditional curative products did not perform as well; acephate and trichlorfon provided 43 and 20-55% control, respectively. In NH, two trials in May were unsuccessful due to heavy rainfall (Swier). A curative trial on June 15 targeted larvae. The fairway was already showing damage. Rated 11 DAT, indoxacarb (0.22 lb a.i./a) provided 87% control, the same as the standard trichlorfon (8.17 lb a.i./a). Chlorantraniliprole gave 67% control (0.5 lb a.i./a) and clothianidin gave 58%, but was not significantly different from the untreated check. In PA, four efficacy trials were conducted on experimental and registered insecticide formulations to suppress ABW (Heller). Preventive spring applications of chlorantraniliprole, lambda cyhalothrin and bifenthrin gave >96% control of adults, but clothianidin was not effective. Curative spring applications of spinosad and trichlorfon gave >90% control of larvae. In NJ, field efficacy trials were conducted in early and late May (Koppenhöfer). Results from early May applications were chlorantraniliprole 85-100%, bifenthrin 85-93%, clothianidin 78% and indoxacarb 56-71%. Results from late May applications were bifenthrin 54-69% and clothianidin 63%. In the area of biological control, the distribution of naturally occurring entomopathogenic nematodes in the soil profile were studied in tandem with ABW populations (Obj. 2) (Koppenhöfer). Vertical soil sampling of two transects revealed that neither H. bacteriophora nor S. carpocapsae were found in the uppermost soil profile (0-5 cm) 3 wk following infection when second generation ABW larvae were likely to be present at this depth (Koppenhöfer). H. bacteriophora was found as deep as 15 cm during this period, returning to the surface in the end of August when conditions improved. S. carpocapsae went undetected between the middle of July and early August, suggesting that this species recolonizes golf course fairways from surrounding areas. The results suggest that inundative applications of nematodes against the first generation ABW larvae is unlikely to have a residual effect on the second generation larvae since the nematodes do not persist at the soil surface. In laboratory assays against adult ABW, EPNs provided only moderate control, even under optimal conditions (Koppenhöfer). Evaluation of EPNs in laboratory assays and field trials against first generation larvae provided high levels of control. EPNs were applied to field infested turf cores containing 4th and 5th instars and pupae in laboratory assays. Significant reductions in numbers were observed against 4th instars, yet low numbers in the following assays made it difficult to determine pathogenicity to 5th instars and pupae. Field trials using one endemic and four commercially available EPNs indicate that high levels of control can be achieved with well timed applications against first generation soil stages. However, due to variability in the data and somewhat different ranking between laboratory and field experiments, further experiments will have to be conducted to determine which EPN species may be the most promising for ABW control. In the area of new cultural control options, four field studies were initiated in 2006 to examine the impact of irrigation, equipment operation and topdressing practices on anthracnose on P. annua greens in NJ. The first study sought to identify irrigation practices that predispose P. annua putting green turf to anthracnose (Clarke, Huang, Inguagiato, Murphy). Treatments included daily replacement of evapotranspiration (ET) with irrigation at 100, 80, 60 and 40% of ET, resulting in plots that ranged from excessively wet to very dry soil water contents. Anthracnose severity was greatest in plots maintained with 40% ET replacement on 28 July 2006. Irrigation at 60% ET on this date had less disease than 40%, but more than 80 and 100% replacement which did not differ from each other. By 25 August, turf at 100% ET had as much anthracnose as turf receiving 40% ET replacement; moderate irrigation levels of 60 and 80% had the least disease on 25 August. These data illustrate that both over- and under- watering turf can increase this disease and that drought stress may predispose turf to anthracnose more rapidly than liberal irrigation (100% ET). A second field study was conducted in 2006 to determine whether lightweight vibratory or sidewinder rollers differentially affect anthracnose severity and if the location of equipment operation (putting green center versus perimeter) influences the disease (Clarke, Inguagiato, Murphy). The 2006 experiment was arranged as a 3 x 2 factorial using a split-block design with eight replications. Rolling treatments (sidewinder roller, vibratory roller and no roller) were oriented as strips perpendicular to the location blocks. Plots were mowed daily (7 days wk-1) with a John Deere 220B walk behind mower bench-set at 3.2-mm. The perimeter block treatment also received daily clean-up passes with the mower. Rolling was done every other day after mowing in the morning. Disease intensity was low in this study during 2006, as were the number of disease observations. Three observations of disease incidence were made during the 2006 growing season. Both forms of rolling increased disease on 11 September compared to non-rolled turf. Anthracnose was greater in plots treated as the center of a putting green on 18 August. However, anthracnose was 13-17% greater in perimeter plots than center plots on the last two rating dates. More data will be required in 2007 and 2008 before any conclusions can be drawn from this research trial. The third study was established to evaluate the effect of sand topdressing rate and frequency on anthracnose (Clarke, Inguagiato, Murphy). Three sand rates (0 , 0.3 and 0.6 L m-2) and three topdressing frequencies (7, 14 and 28 days) were applied in a factorial arrangement to P. annua putting green turf maintained according to standard management practices for the Northeast. Sand rate affected anthracnose on 12 July, where 0.3 L m-2 increased severity compared to no sand, indicating that topdressing may initially encourage disease. However, less disease was observed in topdressed plots compared to non-topdressed plots from 7 to 16 August. As sand rate increased, disease was reduced from 28 August to 6 September. Topdressing frequency had no effect on disease until 7 August. From this date until the end of the study (9 September), anthracnose was reduced in plots topdressed every 7 days compared to either the 14- or 28-day intervals. An interaction between rate and frequency in August and September indicated a cumulative benefit of sand topdressing. In early August, there was no effect of topdressing rate on a 28-d schedule, 0.6 L m-2 had less disease than no sand but was not different than 0.3 L m-2 on a 14-d schedule; and both 0.6 and 0.3 L m-2 had less anthracnose than no sand on a 7-d schedule. By late August, plots topdressed every 28-d at 0.6 L m-2 had less anthracnose than either the 0.3 L m-2 or non-topdressed plots. A reduction of disease was also apparent at 0.6 L m-2 every 14 days and at 0.6 and 0.3 L m-2 every 7 days compared to the respective lower rate treatments. By September, anthracnose was less severe in plots receiving 0.6 L m-2 of sand at all topdressing intervals, or 0.3 L m-2 of sand at both the 7- and 14-day intervals but not every 28 days. Contrary to the initial hypothesis, this first year of data indicated that sand topdressing had a cumulative beneficial effect and that light frequent applications provided the most rapid and substantial reduction of anthracnose. Topdressing practices using increased sand rates (1.2 L ha-1) on a less frequent interval (21 and 42 days) were also evaluated in this study. The addition of 1.2 L ha-1 every 21 or 42 days reduced disease compared to non-topdressed turf by 7 August. The cumulative amount of sand applied on 3 August for the 21- and 42-day schedules was comparable to the amount of sand applied by the 0.3 L ha-1 treatment on a 7-day schedule and the 0.6 L ha-1 treatment on a 14-day schedule. Topdressing on 21-day schedule reduced anthracnose to a greater extent (28 August) than topdressing on a 42-day schedule. The new fourth study initiated in 2006 examined the effect of topdressing sand particle shape (sub-angular vs. rounded) and incorporation method on anthracnose of a P. annua putting green (Clarke, Inguagiato, Murphy). The experiment was arranged as 4 x 3 factorial using a split-plot design with incorporation method as the main plot and sand type as sub-plot. Topdressing was applied using dried sand after dew and gutation water had dried from the turf canopy. Eight passes were made with either soft- or stiff-bristled brushes to incorporate the sand and to achieve variable degrees of turf bruising. Incorporation with vibratory rolling was done with one pass over plots immediately after sand application and two additional passes (once each afternoon for 2 days after sand application). The entire area was hand watered on the day of topdressing immediately after the other incorporation techniques (brushing and rolling) were completed. There were no differences among the four incorporation methods evaluated in this study. A differential response of anthracnose to sand type was observed in July compared to August and September. On 7 July, plots topdressed with round sand had more disease than plots treated with sub-angular or no sand. Greater disease was still observed in plots topdressed with rounded sand on 14 July, however there was no longer a difference between non-topdressed and sub-angular sand plots. The anthracnose response to sand topdressing changed from 7 August to 13 September when there was no difference between sub-angular and rounded sands and each of these sands reduced anthracnose by 14-47% and 14-48%, respectively, compared to non-topdressed plots. Results from this study corroborate the findings of the previous study that anthracnose may be initially enhanced by sand topdressing, but the cumulative effect of light-frequent sand topdressing provided a beneficial reduction in anthracnose severity and that brushing did not enhance disease. In the area of new genetic control options, 12 cultivars and selections and 150 germplasm selections of creeping bentgrass were inoculated during the summer of 2006 with five isolates of C. cereale (Bonos). The isolates from bentgrass were chosen specifically for their virulence to creeping bentgrass. Inoculations were conducted on three consecutive evenings in early August (after 5:30 pm) with a conidial suspension (50,000 conidia/ml) applied with a backpack sprayer. The test area was covered each night with plastic that was removed the next morning. Verticutting and grooming were conducted immediately prior to inoculations. Unfortunately, no infection occurred in 2006. In the area of host plant resistance, 28 selections of P. annua from Penn State University (Huff) were planted in a randomized complete block design (three replicates) on a research farm at the University of RI on 13 June 2006 (Alm). These plots were managed in order to have material on hand to study the interaction of turf and landscape cultural practices on ABW biology, in particular feeding preference studies planned for 2007-2009. Results were summarized from a survey of ABW densities stemming from a widespread natural infestation on field plots at Cornells Turf and Landscape Research Center (Peck, Rossi). This was a first opportunity to collect data on variation in incidence across replicated plots of 20 cultivars and combinations. Results showed a significant effect of cultivar on the abundance of ABW life stages extracted from soil cores. Abundance varied from 0 to 37 individuals/ft2. Objective 3. Develop improved IPM decision tools for managing ABW and anthracnose on golf courses. In the area of rearing techniques and economic thresholds, some progress has been made with rearing ABW in the laboratory on its natural hosts and on artificial diet (Koppenhöfer, Peck). We are presently testing artificial diets on which the larvae are feeding and appear to be developing. These procedures need to be further pursued and refined. In the area of prediction models, data from 3 yr of population data are being coalesced to establish a preliminary degree-day model to predict ABW phenology (Peck). Various models are being assessed to establish the best minimum temperature threshold and the degree of predictive power. Results indicate a good correspondence between the timing of the larvae and adults of the spring generation with growing degree-days, but not with calendar date. With respect to monitoring tools, we are testing whether larval density can be predicted by adult density based on collections made with an inverted leaf blower (Koppenhöfer). Initial observations indicate that this may be a useful monitoring method, but ongoing experiments will have to confirm and further refine this approach. In addition, 12 pitfall traps were designed and built for studies on developing better monitoring tools for ABW adults (Alm). These traps will be installed and evaluated during the 2007-2009 field seasons. In the area of insecticide resistance management, collections of adult populations were made from golf courses in NH where pyrethroids still are providing effective control (Swier). Those insects were tested to gather additional information about differences among populations with respect to adult ABW sensitivity to pyrethroids (Cowles). Results reveal that some populations are functionally resistant to pyrethroids and that the spatial variation in susceptibility is quite fine-grained. For instance, susceptible populations in Somers, CT are only ~25 miles from other CT courses where populations are pyrethroid-resistant. At the field rate dosage, populations experiencing <20% mortality can be classified as resistant, while those experiencing nearly 100% mortality would be classified as susceptible. Populations with an intermediate level of resistance, where pyrethroid resistance is in the process of developing, have not been encountered. Additional funds were secured to address this area through a joint research-extension proposal funded by the Northeast Regional IPM Program (Cowles, with Alm, Heller, Koppenhöfer, Peck, Vittum). Objective 4. Develop best management practices for annual bluegrass on golf courses that will help reduce the economic and environmental costs associated with pesticides currently used to control ABW and anthracnose. An adhoc committee (Heller, Murphy, Peck, Wong) was created to summarize project results into a dynamic best management practices document that will be updated yearly to reflect new advances. An outline has been developed.

Journal articles (refereed) Crouch, J., B.B. Clarke and B.I. Hillman. 2005. Biology and phylogenetic relationships of Colletotrichum isolates from turfgrass in North America. J. Int. Turf Soc. 10:186-195. Crouch, J., B.B. Clarke and B.I. Hillman. 2006. Unraveling the evolutionary relationships among the divergent lineages of Colletotrichum causing anthracnose disease in turfgrass and maize. Phytopathology 96:46-60. Crouch, J.A., B.B. Clarke and B.I. Hillman. 2007. Transposons and sex: What do they mean for Colletotrichum cereale?. Phytopathology (in press). Crouch, J.A., M.R. Thon, B.B. Clarke, L.J. Vaillancourt and B.I. Hillman. 2007. Genomic architecture of the mating-type gene cluster in graminicolous species of the genus Colletotrichum and across the Ascomycota. Phytopathology (in press). Diaz, M.D. and D.C. Peck. 2007. Overwintering of annual bluegrass weevils, Listronotus maculicollis (Dietz) (Coleoptera: Curculionidae), in the golf course landscape. Entomol. Exp. et Appl. (in press). Hao, L., T. Hsiang and P.H. Goodwin. 2006. Role of two cysteine proteinases in the susceptible response of Nicotiana benthamiana to Colletotrichum destructivum and hypersensitive response to Pseudomonas syringae pv. tomato. Plant Science 170:1001-1009. Journal articles (non-refereed) Cook, P.J., P.J. Landschoot and M. Schlossberg. 2006. Phosphonate products for disease control and putting green quality. Golf Course Management 74 (4):93-96. Crouch, J.A., P.R. Johnston and B.I. Hillman. 2007. Species concepts in the genus Colletotrichum: Are we finally moving towards a consistent and accurate system of classification after 50 years of von Arxian generalizations? Innoculum (in press). Kaminski, J.E. 2006. Anthracnose: a five-year multistate initiative. Connecticut Clippings. Kaminski, J.E. 2006. Anthracnose: a five-year multistate initiative. Long Island Golf Course Superintendents Newsletter. Kaminski, J.E. 2006. Anthracnose: a five-year multistate initiative. Vermont Golf Course Superintendents Association Newsletter. Kaminski, J.E. 2007. The increasing problems with anthracnose basal rot. Bayer GOLF ADVANTAGE. Kaminski, J.E. and M.G. Keneally. 2007. Preventive control of anthracnose basal rot on an annual bluegrass putting green, 2006. Plant Disease Management Reports 1:T012. Koppenhöfer A.M. and B.A. McGraw. 2006. Management of the annual bluegrass weevil on golf courses: Developing new approaches. Clippings & Green World 61:20-22. Koppenhöfer A.M. and B.A. McGraw. 2007. Development of new management tools for the annual bluegrass weevil on golf courses. The Greenerside 31(2):4-11. Landschoot, P.J. and P.J. Cook. 2005. Sorting out the phosphonate products. Golf Course Management 73(11):73-77. Peck, D.C. and M.D. Diaz. 2007. Dont fear the weevil!: Managing the annual bluegrass weevil. Cornell University Turfgrass Times 18(1): 4 pp. Swier, S.R., A. Rollins and A. Collins. 2007. Efficacy of DPX E2Y45, Provaunt, and Arena compared to Dylox as a rescue treatment for annual bluegrass weevil, 2006. Arthropod Management Tests 32 (in press). Proceedings Clarke, B.B., P.R. Majumdar, D. Fitzgerald, M. Peacos, P. Goldberg, K. Gaugler, L. Jepsen and J. Inguagiato. 2006. Management of anthracnose basal rot on an annual bluegrass green with selected fungicides, p. 193-200. In: Rutgers Turfgrass Proceedings, 2005, A.G. Gould, ed. Center for Turfgrass Science and the New Jersey Turfgrass Association, New Brunswick, NJ. Vol. 37. Crouch, J.A., F. Wong, L.P. Tredway, T. Hsiang, B.B. Clarke and B.I. Hillman. 2006. Assessing population structure among divergent lineages of Colletotrichum cereale pathogenic to cool-season turfgrass species in North America, p. 34. In: Proc. 15th Annual Rutgers Turfgrass Symp., B. Park and B. Fitzgerald, eds. Center for Turfgrass Science, Rutgers University, New Brunswick, NJ. Crouch, J.A., B.B. Clarke and B.I. Hillman. 2007. Evolution of host specialization in Colletotrichum cereale associated with grasses from golf course greens, cereal crops and native prairies, p. 41. In: Proc. 16th Annual Rutgers Turfgrass Symp., J. Heckman, M. Provance-bwoley, B. Fitzgerald, eds. Center for Turfgrass Science, Rutgers University, New Brunswick, NJ. Hillman, B.I., J.A. Crouch and B.B. Clarke. 2006. Colletotrichum cereale, the causal agent of turfgrass anthracnose: Some properties of the pathogen in agronomic and wild grasses, p. 26. In: Proc. 15th Annual Rutgers Turfgrass Symp., B. Park and B. Fitzgerald, eds. Center for Turfgrass Science, Rutgers University, New Brunswick, NJ. Inguagiato, J.C., J.A. Murphy and B. B. Clarke. 2006. Development of best management practices for controlling anthracnose and maintenance of ball roll distance, p. 38. In: Proc. 15th Annual Rutgers Turfgrass Symp., B. Park and B. Fitzgerald, eds. Center for Turfgrass Science, Rutgers University, New Brunswick, NJ. Inguagiato, J.C., J.A. Murphy and B.B. Clarke. 2007. Developing best management practices for anthracnose control on annual bluegrass greens: summarizing four years of field research, pp. 26-29. In: Proc. 16th Annual Rutgers Turfgrass Symp., J. Heckman, M. Provance-bwoley, B. Fitzgerald, eds. Center for Turfgrass Science, Rutgers University, New Brunswick, NJ. Koppenhöfer, A.M. and B.A. McGraw. 2006. Development of new management tools for the annual bluegrass weevil on golf courses, pp. 179-181. In: Rutgers Turfgrass Proceedings, 2005, A.G. Gould, ed. Center for Turfgrass Science and the New Jersey Turfgrass Association, New Brunswick, NJ. Vol. 37. McGraw, B.A. and A.M. Koppenhöfer. 2007. Biological control of the annual bluegrass weevil using entomopathogenic nematodes, pp. 33-34. In: Proc. 16th Annual Rutgers Turfgrass Symp., J. Heckman, M. Provance-bwoley, B. Fitzgerald, eds. Center for Turfgrass Science, Rutgers University, New Brunswick, NJ. Peck, D.C. and M. Diaz. 2005. Challenges and perspectives for managing the annual bluegrass weevil, pp. 23-24. In: Proc 14th Annual Rutgers Turfgrass Symposium, D. Gimenez and B. Fitzgerald, eds. Center for Turfgrass Science, Rutgers University, New Brunswick, NJ. Published abstracts Crouch, J., B.B. Clarke and B.I. Hillman. 2006. Evolution of host specialization in sympatric species of the fungus Colletotrichum associated with grasses in prairies and monocultured agroecosystems. The Land Institute Natural Systems Agriculture Workshop, June 11-17, 2006, Matfield Green, KS. Crouch, J., B.B. Clarke and B.I. Hillman. 2006. Evolutionary relationships of fungi in the genus Colletotrichum from diverse grass communities. Innoculum 57(4):14-15. http://www.msafungi.org/57(4).pdf Crouch, J.A., B.B. Clarke and B.I. Hillman. 2007. Implications of repeat-induced point mutated transposable elements during the evolution of Colletotrichum cereale. Fungal Genetics Newsletter, 24th Fungal Genetics Conference, March 20-25, 2007, Asilomar, CA. http://www.fgsc.net/asil2007/xxivFGCposterAbs.htm Crouch, J.A., B.B. Clarke and B.I. Hillman. 2007. Implications of repeat-induced point mutated transposable elements during the evolution of Colletotrichum cereale. Theobald Smith Society Waksman Lectureship Meeting, May 3, 2007, New Brunswick, NJ. http://users.tellurian.com/tss/Abstracts.pdf Crouch, J.A., B.B. Clarke and B.I. Hillman. 2007. Patterns of recombination and population differentiation among Colletotrichum cereale isolates from 27 host plant genera. Fungal Genetics Newsletter, 24th Fungal Genetics Conference, March 20-25, 2007, Asilomar, CA. http://www.fgsc.net/asil2007/xxivFGCposterAbs.htm Crouch, J.A., P.R. Johnston and B.I. Hillman. 2007. Striking a balance between phylogenetic history, character diagnosis and rank-based systems of taxonomical nomenclature in the genus Colletotrichum. Colletotrichum Workshop, 24th Fungal Genetics Conference, March 26, 2007, Asilomar, CA. http://www.colletotrichum.org/ Crouch, J.A., B.B. Clarke and B.I. Hillman. 2007. Evolution of Colletotrichum associated with grasses from golf course greens, cereal crops and native prairies. Mid-Atlantic States Mycology Conference, Mycological Society of America, April 21-22, 2007, Beltsville, MD. Crouch, J.A., B.B. Clarke and B.I. Hillman. 2007. Evolution of host specialization in Colletotrichum cereale associated with grasses from golf course greens, cereal crops and native prairies. Microbiology at Rutgers University: Cultivating traditions, current strength, and future frontiers. Theobald Smith Society, Rutgers University, New Brunswick, N.J. Crouch, J.A., M.R. Thon, M. Groenner-Penna, B.B. Clarke, A. Vilas-Boas, L.J. Vaillancourt and B.I. Hillman. 2007. Characterizing the mating-type locus of the graminicolous Colletotrichum: Patterns of sex, selection and host specialization. Fungal Genetics Newsletter, 24th Fungal Genetics Conference, March 20-25, 2007, Asilomar, CA. http://www.fgsc.net/asil2007/xxivFGCposterAbs.htm Inguagiato, J.C., J.A. Murphy and B.B. Clarke. 2006. Effect of mowing and rolling practices on anthracnose severity of an annual bluegrass putting green. Phytopathology 96(6):S 96. Inguagiato, J.C., J.A. Murphy and B.B. Clarke. 2006. Effect of chemical growth regulation strategies on anthracnose severity of annual bluegrass putting green turf. Agronomy Abstracts 98:C0570-22 (http://www.asa-cssa-sssa.org/anmeet). Manuscripts in review Crouch, J.A., B.M. Glasheen, M.A. Giunta, B.B. Clarke and B.I. Hillman. Submitted. The evolution of transposon repeat-induced point mutation in the genome of Colletotrichum cereale: Reconciling sex, recombination and homoplasy in an "asexual" pathogen. Fungal Genet. Biol. (in revision, 46 manuscript pages). Crouch, J.A., B.M. Glasheen, W. Udin, B.B. Clarke and B.I. Hillman. Submitted. Patterns of diversity in lineages of Colletotrichum cereale as revealed by RIP-mutated transposable elements. Fungal Genet. Biol. (in revision, 35 manuscript pages). Inguagiato, J.C., J.A. Murphy and B.B. Clarke. Submitted. Anthracnose severity on annual bluegrass influenced by nitrogen fertilization, growth regulators, and verticutting. Crop Sci. (in review, 39 manuscript pages). Others Diaz, M.D. 2006. Population dynamics, phenology and overwintering behavior of the annual bluegrass weevil, Listronotus maculicollis Dietz (Coleoptera: Curculionidae), in the golf course landscape. M.S. thesis, Field of Entomology, Cornell University, Ithaca, NY. 92 pp. Kaminski, J. and T. Hsiang, T. 2007. A Five-Year North American Research Initiative on Annual Bluegrass Pests. http://www.uoguelph.ca/~thsiang/turf/anth2007/ (online as of 2007/5/4). Peck, D.C., M.D. Diaz & M. Seto. 2007. Annual bluegrass weevil (also known as the Hyperodes weevil), Listronotus maculicollis Dietz. Electronic factsheet (English and Spanish versions), NYS IPM Program Fact Sheet Series (www.nysipm.cornell.edu/factsheets/turfgrass/default.asp).