+publisher:"Texas A&M University" +contributor:("Harris, Marvin K.")

Texas A&M University

1. Hartfield, Emilie Anne. Molecular and Pheromone Studies of Pecan Nut Casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae).

Degree: MS, Entomology, 2011, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7488

► The pecan nut casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae) is the most damaging insect pest of pecan, Carya illinoinensis (Wang) K. Koch (Fagales: Juglandaceae). Two… (more)

▼ The pecan nut casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae) is the most damaging insect pest of pecan, Carya illinoinensis (Wang) K. Koch (Fagales: Juglandaceae). Two sex pheromones have been identified for this species and are currently being used to assist pecan growers in the timing of insecticide applications. The discovery that there are two pheromone types produced by A. nuxvorella has led to complications in the implementation of pheromone monitoring programs. One pheromone (referred to as standard) is attractive to moths in the southern US, but not in Mexico. The other pheromone (referred to as Mexican) is attractive to moths in the southern US and in Mexico. Because most male lepidopterans respond only to a specific pheromone, it was suspected that there were two pheromone strains of A. nuxvorella, one exclusively present in the northern distribution of A. nuxvorella (US strain) and the other widely distributed from Sonora, Chihuahua, and Durango in Northern Mexico to Texas, Georgia, and Oklahoma in the US (Mexican strain). In order to confirm the existence of the two alleged pheromone strains, AFLP markers were obtained and analyzed, male response to pheromones was observed and phenological differences were assessed. Additionally, the relative abundance of each of the two pherotypes was evaluated and the population structure of this pest across its geographic distribution was determined. Results of genetic analysis show that the genetic differentiation between these insects is not explained by pheromone type. This information is further supported by a pheromone assay in which a large proportion of US collected A. nuxvorella males and Mexican collected A. nuxvorella males chose both pheromones when tested multiple times. Furthermore, no phenological differences were detected between the two pherotypes in the US, although significantly more male A. nuxvorella in the US are attracted to field-deployed pheromone traps baited with the standard pheromone than the Mexican pheromone. Finally, population genetic analyses indicate a high degree of genetic structure in A. nuxvorella across its geographic distribution, with the genetically distinct populations occurring in areas where A. nuxvorella is not native, but has been introduced. Advisors/Committee Members: Medina, Raul F. (advisor), Harris, Marvin K. (advisor), Jones, Adam G. (committee member).

Subjects/Keywords: Pecan nut casebearer; AFLP; population structure; pheromone

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APA (6^th Edition):

Hartfield, E. A. (2011). Molecular and Pheromone Studies of Pecan Nut Casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae). (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7488

Chicago Manual of Style (16^th Edition):

Hartfield, Emilie Anne. “Molecular and Pheromone Studies of Pecan Nut Casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae).” 2011. Masters Thesis, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7488.

MLA Handbook (7^th Edition):

Hartfield, Emilie Anne. “Molecular and Pheromone Studies of Pecan Nut Casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae).” 2011. Web. 03 Mar 2021.

Vancouver:

Hartfield EA. Molecular and Pheromone Studies of Pecan Nut Casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae). [Internet] [Masters thesis]. Texas A&M University; 2011. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7488.

Council of Science Editors:

Hartfield EA. Molecular and Pheromone Studies of Pecan Nut Casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae). [Masters Thesis]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7488

Texas A&M University

2. Dickey, Aaron. Host-Associated Differentiation in an Insect Community.

Degree: PhD, Entomology, 2011, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8695

► Host-Associated Differentiation (HAD) is the formation of genetically divergent hostassociated lineages maintained by ecological isolation. HAD is potentially an important route to ecological speciation in… (more)

▼ Host-Associated Differentiation (HAD) is the formation of genetically divergent hostassociated lineages maintained by ecological isolation. HAD is potentially an important route to ecological speciation in parasites including many insects. While HAD case studies are accumulating, there is a dearth of negative results in the literature making it difficult to know how common the phenomenon really is or whether there are specific traits of parasites which promote HAD. To address these two problems, studies are needed which both publish negative results (i.e., parasites not showing HAD) and test for HAD in multiple parasite species on the same pair of host species (i.e., control for host plant effects). In this study, HAD was tested in three species of herbivorous insects and one parasitoid species on the same two host tree species: pecan and water hickory. The insects were selected based on the presence or absence of two traits, parthenogenesis and endophagy. A test for HAD was considered “positive” when population substructure was explained by host-association. To test for the presence of HAD, insects were sampled sympatrically to eliminate geographical isolation as a confounding factor, sampling was replicated spatially to assure that HAD persisted, and multiple loci were sampled from each individual. Genetic data was analyzed using cluster analyses. HAD was found in both pecan leaf phylloxera and yellow pecan aphid but not in pecan bud moth or in the parasitoid of the yellow pecan aphid, Aphelinus perpallidus. Interestingly, both taxa showing HAD are parthenogenetic and both taxa not showing HAD reproduce sexually. Species showing HAD were tested for the presence of a pre-mating reproductive isolating mechanism (RIM) which could be maintaining HAD despite the potential for gene flow. Selection against migrants to the alternative host was tested in yellow pecan aphid using a no-choice fitness experiment. The overall contribution of this RIM to total isolation was positive and ranged from 0.614 to 0.850. The RIM of “habitat preference” was tested in pecan leaf phylloxera using a dual-choice preference experiment. In this species, preference was only detected for phylloxera originating from water hickory suggesting that host discrimination ability may be a less important factor promoting differentiation in phylloxera. Advisors/Committee Members: Medina, Raul F. (advisor), Eubanks, Micky D. (committee member), Harris, Marvin K. (committee member), DeWitt, Thomas J. (committee member).

Subjects/Keywords: Parthenogenesis; Endophagy; Aphids; Carya, Solidago, Genetic Differentiation; Amplified Fragment Length Polymorphisms; Host-Parasite Interactions; Reciprocal Transplant; Host Plant Discrimination; Sequential Radiation

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APA (6^th Edition):

Dickey, A. (2011). Host-Associated Differentiation in an Insect Community. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8695

Chicago Manual of Style (16^th Edition):

Dickey, Aaron. “Host-Associated Differentiation in an Insect Community.” 2011. Doctoral Dissertation, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8695.

MLA Handbook (7^th Edition):

Dickey, Aaron. “Host-Associated Differentiation in an Insect Community.” 2011. Web. 03 Mar 2021.

Vancouver:

Dickey A. Host-Associated Differentiation in an Insect Community. [Internet] [Doctoral dissertation]. Texas A&M University; 2011. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8695.

Council of Science Editors:

Dickey A. Host-Associated Differentiation in an Insect Community. [Doctoral Dissertation]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8695

3. Chammoun, Christopher James. Production Model and Consumer Preferences for Texas Pecans.

Degree: MS, Agricultural Economics, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11501

► High prices in any industry, agricultural especially, tend to spur new investment opportunities. Recent prices for pecans have been high relative to their historical pattern,… (more)

Subjects/Keywords: conjoint analysis; choice experiment; stochastic; empirical distribution

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APA (6^th Edition):

Chammoun, C. J. (2012). Production Model and Consumer Preferences for Texas Pecans. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11501

Chicago Manual of Style (16^th Edition):

Chammoun, Christopher James. “Production Model and Consumer Preferences for Texas Pecans.” 2012. Masters Thesis, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11501.

MLA Handbook (7^th Edition):

Chammoun, Christopher James. “Production Model and Consumer Preferences for Texas Pecans.” 2012. Web. 03 Mar 2021.

Vancouver:

Chammoun CJ. Production Model and Consumer Preferences for Texas Pecans. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11501.

Council of Science Editors:

Chammoun CJ. Production Model and Consumer Preferences for Texas Pecans. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11501

Texas A&M University

4. Puckett, Robert T. Biological and Ecological Aspects of Field Released Fire Ant Decapitating Flies Pseudacteon spp. (Diptera: Phoridae), Parasitoids of Red Imported Fire Ants Solenopsis invicta Buren (Hymenoptera: Formicidae).

Degree: PhD, Entomology, 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-148

► Multiple Pseudacteon phorid fly species, including P. tricuspis and P. curvatus, have been released in the southern United States beginning in 1997 and 2003 (respectively)… (more)

▼ Multiple Pseudacteon phorid fly species, including P. tricuspis and P. curvatus, have been released in the southern United States beginning in 1997 and 2003 (respectively) to serve as biological control agents against red imported fire ants Solenopsis invicta Buren (hereafter referred to as RIFA). Field research in the United States on phorid/RIFA interactions has addressed establishment and spread of released species. Additionally, studies are needed on phorid biology and ecology with respect to spatial distribution and phenology, phorid/habitat associations and phorid-mediated affects on RIFA foraging patterns. A suite of manipulative laboratory and field experiments/observations were conducted to 1) develop a novel phorid sampling device to provide uniform and repeatable sampling of flies, 2) assess spatial distributions and phenology of Pseudacteon tricuspis and P. curvatus, 3) assess P. tricuspis and P. curvatus habitat associations and 4) assess phorid-mediated affects on RIFA foraging patterns and caste ratios. PTS Traps (developed for this research) are significantly more effective than previous sampling methods in terms of mean number of flies collected, efficiency of use and % trap success. Data collected with these traps allowed for the determination of patterns of species-specific phenology and relative densities through time and speciesspecific numerical/spatial superiority (Chapter IV). P. curvatus was significantly more abundant than P. tricuspis in only one of the habitat types sampled (df (160) = 4.57, P < 0.005). P. tricuspis densities did not differ significantly among habitat type. Llaboratory experiments revealed that phorid-exposed RIFA colonies foraged less intensively diurnally (df = 1,558; P < 0.05) and more intensively nocturnally (df = 778; P < 0.05) relative to control colonies. Field data regarding this compensatory nocturnal foraging shift did not corroborate those of the laboratory work. In the field there was no significant difference in foraging intensity during nocturnal (df (18) = -0.486, P = 0.633) and diurnal (df (18) = 1.375 P = 0.186) sampling periods. Lastly, chi-square analysis of RIFA forager size-classes revealed significant differences between phorid-infested (treatment) and phorid-free (control) sites (X 2 = 6811.85, df = 3, P < 0.05) with a significantly greater proportion of small RIFA foragers at the phorid-infested site. Advisors/Committee Members: Harris, Marvin K. (advisor), Wharton, Robert A. (committee member), Vinson, Bradleigh (committee member), Winemiller, Kirk O. (committee member).

Subjects/Keywords: Keyword 1; Phoridae, Formicidae, Pseudacteon spp., Solenopsis invicta, PTS Trap, Biological Control

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APA (6^th Edition):

Puckett, R. T. (2010). Biological and Ecological Aspects of Field Released Fire Ant Decapitating Flies Pseudacteon spp. (Diptera: Phoridae), Parasitoids of Red Imported Fire Ants Solenopsis invicta Buren (Hymenoptera: Formicidae). (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-148

Chicago Manual of Style (16^th Edition):

Puckett, Robert T. “Biological and Ecological Aspects of Field Released Fire Ant Decapitating Flies Pseudacteon spp. (Diptera: Phoridae), Parasitoids of Red Imported Fire Ants Solenopsis invicta Buren (Hymenoptera: Formicidae).” 2010. Doctoral Dissertation, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-148.

MLA Handbook (7^th Edition):

Puckett, Robert T. “Biological and Ecological Aspects of Field Released Fire Ant Decapitating Flies Pseudacteon spp. (Diptera: Phoridae), Parasitoids of Red Imported Fire Ants Solenopsis invicta Buren (Hymenoptera: Formicidae).” 2010. Web. 03 Mar 2021.

Vancouver:

Puckett RT. Biological and Ecological Aspects of Field Released Fire Ant Decapitating Flies Pseudacteon spp. (Diptera: Phoridae), Parasitoids of Red Imported Fire Ants Solenopsis invicta Buren (Hymenoptera: Formicidae). [Internet] [Doctoral dissertation]. Texas A&M University; 2010. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-148.

Council of Science Editors:

Puckett RT. Biological and Ecological Aspects of Field Released Fire Ant Decapitating Flies Pseudacteon spp. (Diptera: Phoridae), Parasitoids of Red Imported Fire Ants Solenopsis invicta Buren (Hymenoptera: Formicidae). [Doctoral Dissertation]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2008-12-148

5. Irungu, Rose Wambui. Effects of spinosad and lambda-cyhalothrin on their targets, cabbage looper, Trichoplusia ni, and diamondback moth, Plutella xylostella, and on their non-targets, spiders, on cabbage in south Texas.

Degree: MS, Entomology, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2509

► A randomized block experiment was conducted in cabbage fields at Texas Agriculture Experiment Station at Weslaco in the spring and fall 2005 and spring 2006.… (more)

▼ A randomized block experiment was conducted in cabbage fields at Texas Agriculture Experiment Station at Weslaco in the spring and fall 2005 and spring 2006. There were four blocks and two pesticide treatments, spinosad (SpinTor®), lambda- cyhalothrin (Warrior®), and an untreated control. The pesticide treatments were for the management of Plutella xylostella L. (Lepidoptera: Plutellidae) and Trichoplusia ni (Hubner) (Lepidoptera: Noctuidae). Pitfall traps captured eight families of spiders in fall 2005, and thirteen families in spring 2006. The most abundant family was Lycosidae with Pardosa delicatula (Gertsch and Wallace) followed by Pardosa pauxilla (Montgomery) and Hogna helluo (Walckenaer) in fall 2005, while in spring 2006 Hogna helluo was most abundant followed by Pardosa delicatula and Pardosa pauxilla. The diversity of spiders in fall 2006 in the lambda-cyhalothrin plots was lower than that of spiders found in the untreated control or the spinosad treated plots, which were up to 2.6 and 2.4 times, respectively, more diverse. In spring 2006, the spiders in untreated control and spinosad treated plots were 1.5 and 1.3 times respectively more diverse than spiders in the lambda-cyhalothrin treated plots. In fall 2005, mean diversity of spiders in spinosad treated plots was 1.1 times more diverse than in the untreated control, although this difference was not statistically significant. In spring 2006, spinosad treated plots had 1.2 times greater diversity than untreated control and this difference was significant. The effects of two insecticide treatments on height, width, and weight of cabbages were highly significant in all three seasons. Cabbage harvest in spinosad and lambda- cyhalothrin plots showed greater height, width, and weight than in untreated control but were not different from each other. However, in the larval damage rating, spinosad treatment showed better management of diamondback moth and cabbage looper than lambda- cyhalothrin. Advisors/Committee Members: Harris, Marvin K (advisor), Liu, Tong-Xian (advisor), Bernal, Julio (committee member), Chandler, James M (committee member).

Subjects/Keywords: spiders; spinosad; lamda-cyhalothrin

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APA (6^th Edition):

Irungu, R. W. (2009). Effects of spinosad and lambda-cyhalothrin on their targets, cabbage looper, Trichoplusia ni, and diamondback moth, Plutella xylostella, and on their non-targets, spiders, on cabbage in south Texas. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2509

Chicago Manual of Style (16^th Edition):

Irungu, Rose Wambui. “Effects of spinosad and lambda-cyhalothrin on their targets, cabbage looper, Trichoplusia ni, and diamondback moth, Plutella xylostella, and on their non-targets, spiders, on cabbage in south Texas.” 2009. Masters Thesis, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2509.

MLA Handbook (7^th Edition):

Irungu, Rose Wambui. “Effects of spinosad and lambda-cyhalothrin on their targets, cabbage looper, Trichoplusia ni, and diamondback moth, Plutella xylostella, and on their non-targets, spiders, on cabbage in south Texas.” 2009. Web. 03 Mar 2021.

Vancouver:

Irungu RW. Effects of spinosad and lambda-cyhalothrin on their targets, cabbage looper, Trichoplusia ni, and diamondback moth, Plutella xylostella, and on their non-targets, spiders, on cabbage in south Texas. [Internet] [Masters thesis]. Texas A&M University; 2009. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2509.

Council of Science Editors:

Irungu RW. Effects of spinosad and lambda-cyhalothrin on their targets, cabbage looper, Trichoplusia ni, and diamondback moth, Plutella xylostella, and on their non-targets, spiders, on cabbage in south Texas. [Masters Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2509

Texas A&M University

6. Ripple, Brandon Wayne. Host plant resistance to Whiteflies, Bemisia tabaci (Gennadius), Biotype B, (Homoptera: Aleyrodidae) in cotton race stocks for breeding improved cotton cultivars.

Degree: MS, Entomology, 2004, Texas A&M University

URL: http://hdl.handle.net/1969.1/239

► Whiteflies (Bemisia tabaci, Biotype B, Homoptera: Aleyrodidae) are pests of cotton crops, affecting the yield of the crop both indirectly and directly. These pests feed… (more)

▼ Whiteflies (Bemisia tabaci, Biotype B, Homoptera: Aleyrodidae) are pests of cotton crops, affecting the yield of the crop both indirectly and directly. These pests feed on the leaves of cotton plants and produce "honeydew," a sticky liquid excretion which covers the lint of the open cotton boll creating problems during the processing of the lint. High densities of these pests also can decrease the productivity of the cotton plant by stripping it of vital nutrients. The primary objective of this research was to screen 116 converted cotton race stocks for resistance to sweetpotato whiteflies. Responses of converted race stocks to whiteflies are compared to that of known susceptible commercial cultivars PSC 355 and Delta Pearl. Screens for antibiosis resistance to whitefly were established using excised leaves placed in a nutrient solution (¼ strength Hoagland's). Cohort populations of whiteflies were established on these leaves and followed daily to determine differences in developmental time as well as percent survival. Resistant candidates were determined using a chi-squared test comparing the ranked sums of leaf averages for the two selection criteria, whitefly developmental time and percent whitefly survival, of each cotton race stock to that of the putative known susceptibles (KS). These tests showed 6 converted race stocks to be significantly different (P ≤ 0.1) from the KS for at least one of the two selection criteria. Of these converted race stocks, M-9044-0154 and M-9044-0156 showed to have lower whitefly survival than the KS, while M-9644-0188, M-9644-0195, M-0044-0221, and M-9644-0242 showed whitefly to have an increased developmental time. Retesting of these six converted race stocks along with several others identified another race stock line, M-0044-0171, which was significantly different from the KS. Retesting also indicated that M-9644-0188 was different for survival in addition to developmental time which was determined in the original screening. Additional tests were conducted in the greenhouse and field to examine these race stock lines. Greenhouse screenings indicated that M-9044-0156 and M-9644-0188 contained possible non-preference resistance characteristics. Field screenings conducted in Weslaco and College Station, TX in 2002 and 2003 failed to provide useful data due to low densities of insects. Advisors/Committee Members: Harris, Marvin K. (advisor), Smith, C. Wayne (advisor), Woolley, James B. (committee member).

Subjects/Keywords: Host Plant Resistance; Whitefly; Bemisia; Converted Race Stocks; Cotton

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APA (6^th Edition):

Ripple, B. W. (2004). Host plant resistance to Whiteflies, Bemisia tabaci (Gennadius), Biotype B, (Homoptera: Aleyrodidae) in cotton race stocks for breeding improved cotton cultivars. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/239

Chicago Manual of Style (16^th Edition):

Ripple, Brandon Wayne. “Host plant resistance to Whiteflies, Bemisia tabaci (Gennadius), Biotype B, (Homoptera: Aleyrodidae) in cotton race stocks for breeding improved cotton cultivars.” 2004. Masters Thesis, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/239.

MLA Handbook (7^th Edition):

Ripple, Brandon Wayne. “Host plant resistance to Whiteflies, Bemisia tabaci (Gennadius), Biotype B, (Homoptera: Aleyrodidae) in cotton race stocks for breeding improved cotton cultivars.” 2004. Web. 03 Mar 2021.

Vancouver:

Ripple BW. Host plant resistance to Whiteflies, Bemisia tabaci (Gennadius), Biotype B, (Homoptera: Aleyrodidae) in cotton race stocks for breeding improved cotton cultivars. [Internet] [Masters thesis]. Texas A&M University; 2004. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/239.

Council of Science Editors:

Ripple BW. Host plant resistance to Whiteflies, Bemisia tabaci (Gennadius), Biotype B, (Homoptera: Aleyrodidae) in cotton race stocks for breeding improved cotton cultivars. [Masters Thesis]. Texas A&M University; 2004. Available from: http://hdl.handle.net/1969.1/239

Texas A&M University

7. Calixto Sanchez, Alejandro Antonio. Diversity, abundance, seasonality and interactions of ants (Hymenoptera: Formicidae) in pecans in Mumford, Robertson Co., Texas.

Degree: MS, Entomology, 2005, Texas A&M University

URL: http://hdl.handle.net/1969.1/1487

► Alpha diversity, population dynamics and interactions of ant assemblages were studied in a pecan orchard located in Mumford, Texas. The assemblages included the invasive species… (more)

▼ Alpha diversity, population dynamics and interactions of ant assemblages were studied in a pecan orchard located in Mumford, Texas. The assemblages included the invasive species Solenopsis invicta Buren, known as the red imported fire ant (RIFA). The study addressed the major question of what is the response of the ant assemblage to the reduction of RIFA following insecticide applications (bait and contact insecticide) and the impact of these on individual species. To address this question three treatments were established in a 16 hectare area in the orchard. The treatments were randomly assigned in 1.33 hectare blocks with four replications and periodically monitored. Treatments were: 1) insect growth regulator (IGR) bait treatment (ExtinguishTM, active compound is 0.5% s-methoprene) applied twice in 2000 and once in 2001; 2) the contact insecticide chlorpyrifos (LorsbanTM) applied on tree trunks four times in 2000 and once in 2001; and 3) untreated Control. Blocks were sampled using pitfall traps, baited vials, direct sampling, and colony counts. Data were analyzed by using ANOVA-GLM with the LSD multiple comparison test to compare the effect of treatment on the ant assemblage (using the Shannon index) and the effect on individual species. Additionally, data obtained from Control plots were used to compare sampling techniques and to determine what method is most efficient for collecting ants in this agroecosystem. Shannon indices were estimated for each method and compared. The ant assemblage consisted of 16 ant species. S. invicta was the most abundant followed by Paratrechina sp. and Monomorium minimum. The IGR treatment consistently reduced RIFA (77%). Native ants were found to coexist with RIFA in the Control and chlorpyrifos plots at lower densities and maintained higher densities in IGR plots. Chlorpyrifos trunk treatment did not have a significant impact on RIFA or native ant densities. The native ant, Dorymyrmex flavus, was greater in IGR plots following RIFA reduction and higher densities were found to persist for more than two years after the last IGR treatment. During this period, D. flavus was observed carrying large numbers of dead RIFA, some taken inside the nest, and some disarticulated RIFA taken out of the nest. RIFA remains were accumulated in D. flavus middens, further indication of an important interaction between these two species. These results indicate D. flavus resisted reinvasion by RIFA. Advisors/Committee Members: Harris, Marvin K. (advisor), Knutson, Allen (committee member), Barr, Charles (committee member), Winemiller, Kirk (committee member).

Subjects/Keywords: Diversity; interactions; ant assemblage; S. invicta; D. flavus; sampling

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APA (6^th Edition):

Calixto Sanchez, A. A. (2005). Diversity, abundance, seasonality and interactions of ants (Hymenoptera: Formicidae) in pecans in Mumford, Robertson Co., Texas. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/1487

Chicago Manual of Style (16^th Edition):

Calixto Sanchez, Alejandro Antonio. “Diversity, abundance, seasonality and interactions of ants (Hymenoptera: Formicidae) in pecans in Mumford, Robertson Co., Texas.” 2005. Masters Thesis, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/1487.

MLA Handbook (7^th Edition):

Calixto Sanchez, Alejandro Antonio. “Diversity, abundance, seasonality and interactions of ants (Hymenoptera: Formicidae) in pecans in Mumford, Robertson Co., Texas.” 2005. Web. 03 Mar 2021.

Vancouver:

Calixto Sanchez AA. Diversity, abundance, seasonality and interactions of ants (Hymenoptera: Formicidae) in pecans in Mumford, Robertson Co., Texas. [Internet] [Masters thesis]. Texas A&M University; 2005. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/1487.

Council of Science Editors:

Calixto Sanchez AA. Diversity, abundance, seasonality and interactions of ants (Hymenoptera: Formicidae) in pecans in Mumford, Robertson Co., Texas. [Masters Thesis]. Texas A&M University; 2005. Available from: http://hdl.handle.net/1969.1/1487

Texas A&M University

8. Mynhardt, Glene. Population genetics of the pecan weevil, Curculio caryae Horn (Coleoptera: Curculionidae), inferred from mitochondrial nucleotide data.

Degree: MS, Entomology, 2006, Texas A&M University

URL: http://hdl.handle.net/1969.1/4388

► The pecan weevil, Curculio caryae Horn, is an obligate nut feeder of all North American hickory (Carya) and a key pest of the pecan, C.… (more)

Subjects/Keywords: COI; Nested Clade Analysis

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APA (6^th Edition):

Mynhardt, G. (2006). Population genetics of the pecan weevil, Curculio caryae Horn (Coleoptera: Curculionidae), inferred from mitochondrial nucleotide data. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/4388

Chicago Manual of Style (16^th Edition):

Mynhardt, Glene. “Population genetics of the pecan weevil, Curculio caryae Horn (Coleoptera: Curculionidae), inferred from mitochondrial nucleotide data.” 2006. Masters Thesis, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/4388.

MLA Handbook (7^th Edition):

Mynhardt, Glene. “Population genetics of the pecan weevil, Curculio caryae Horn (Coleoptera: Curculionidae), inferred from mitochondrial nucleotide data.” 2006. Web. 03 Mar 2021.

Vancouver:

Mynhardt G. Population genetics of the pecan weevil, Curculio caryae Horn (Coleoptera: Curculionidae), inferred from mitochondrial nucleotide data. [Internet] [Masters thesis]. Texas A&M University; 2006. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/4388.

Council of Science Editors:

Mynhardt G. Population genetics of the pecan weevil, Curculio caryae Horn (Coleoptera: Curculionidae), inferred from mitochondrial nucleotide data. [Masters Thesis]. Texas A&M University; 2006. Available from: http://hdl.handle.net/1969.1/4388

Texas A&M University

9. Henderson, Takesha Yvonne. Diversity,distribution, and abundance of ground dwelling spiders at Lick Creek Park, College Station, Texas.

Degree: MS, Entomology, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-1929

► Lick Creek Park is a 515 acre nature park that was acquired in 1987 by the City of College Station, Texas. The site has a… (more)

▼ Lick Creek Park is a 515 acre nature park that was acquired in 1987 by the City of College Station, Texas. The site has a variety of indigenous plant and animal species and is an important natural resource for citizens of the region. There is a long-term commitment to inventory this natural park to monitor the changes as our urban community expands to surround the park. There are 989 species of spiders currently recorded from Texas and 332 of them are known to occur in Brazos County. My focus was on improving the ground spider inventory at Lick Creek Park. Spider collections were made using 18 regularly-sampled pitfall traps distributed evenly among three habitats. Spiders from 24 families, 66 genera, and 111 species were identified from 918 specimens, including 627 immature and 291 adult spiders, captured in pitfall traps from April 2005-April 2006. Of the 111 species found, 45 were represented by one specimen only and 20 were represented by two specimens. Rarefaction analyses indicated that the majority of spider species were readily detectable using pitfall traps and inventoried during this study (111 found and 168 estimated to be present). Simpson’s Diversity measure bootstrap estimates determined species diversity overall to be very diverse (0.966), as did a Shannon Weiner Diversity bootstrap estimate (5.483). Also, Simpson’s measure of species evenness (0.264) indicated a low species evenness. Those species found in only one habitat comprised 50% of the total species, and their densities ranged from 1-5 individuals. Those species found in just two habitats comprised 25% of the total species, and their densities ranged from 2-21 individuals. Species found in all three habitats comprised the remaining 25%, and their densities ranged from 4-53 individuals found. Most species occurred at low densities in this study and this often precluded conducting more detailed analyses. Additional sampling is expected to, first, detect known species occurring in previously unrecorded habitats and, second, to detect species not previously found in the park. This inventory of spiders at Lick Creek will provide a basis for further studies on biodiversity and the assessment of human impact on the environment. Advisors/Committee Members: Harris,Marvin K. (advisor), Jackman,John (committee member), Winemiller, Kirk O. (committee member).

Subjects/Keywords: spider ecology; spider diversity; spiders; ground spiders; spider occurring habitats

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Henderson, T. Y. (2009). Diversity,distribution, and abundance of ground dwelling spiders at Lick Creek Park, College Station, Texas. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1929

Chicago Manual of Style (16^th Edition):

Henderson, Takesha Yvonne. “Diversity,distribution, and abundance of ground dwelling spiders at Lick Creek Park, College Station, Texas.” 2009. Masters Thesis, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-1929.

MLA Handbook (7^th Edition):

Henderson, Takesha Yvonne. “Diversity,distribution, and abundance of ground dwelling spiders at Lick Creek Park, College Station, Texas.” 2009. Web. 03 Mar 2021.

Vancouver:

Henderson TY. Diversity,distribution, and abundance of ground dwelling spiders at Lick Creek Park, College Station, Texas. [Internet] [Masters thesis]. Texas A&M University; 2009. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1929.

Council of Science Editors:

Henderson TY. Diversity,distribution, and abundance of ground dwelling spiders at Lick Creek Park, College Station, Texas. [Masters Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1929

Texas A&M University

10. Trostle Duke, Marcia Katherine. Classical biological control of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), (Diptera:Tephritidae): natural enemy exploration and nontarget testing.

Degree: PhD, Entomology, 2006, Texas A&M University

URL: http://hdl.handle.net/1969.1/3877

► This work covers stages one through seven (of nine stages) of a classical biological control program for Mediterranean fruit fly (=medfly), Ceratitis capitata (Wiedemann). Major… (more)

▼ This work covers stages one through seven (of nine stages) of a classical biological control program for Mediterranean fruit fly (=medfly), Ceratitis capitata (Wiedemann). Major research objectives concentrate on stage five (exploration and collection of natural enemies), and stage seven (testing and selecting natural enemies for additional work). Coffee was collected monthly from three locations in Kenya from November 1997 through July 1999. Four species of tephritid flies and ten parasitoid species were recovered. Four guilds of parasitoids were recorded, and two egg-prepupal endoparasitoids, Fopius caudatus (SzÃ©pligeti) and F. ceratitivorus (Wharton), were discovered. The oviposition behavior of these two species is contrasted. Domination of this tropical parasitoid assemblage by koinobionts is discussed relative to the dominance of temperate fruit-infesting tephritid systems by idiobionts. Fruit handling procedures were examined for impact on overall percent emergence and specifically percent emergence of flies versus parasitoids. It was determined that stirring samples had a significant positive effect on overall emergence, however daily misting of fruit did not. The only treatment without a significant bias in fly emergence over parasitoids was the stirred/dry treatment. Effects of these results on rearing procedures are discussed. Host specificity and host suitability of parasitoids reared from coffee were examined via: (1) association of parasitoids with host flies based on characteristics of the fly puparia from which parasitoids emerged, (2) rearing of cucurbit infesting tephritids and their parasitoids in Kenya, (3) rearing of flowerhead infesting tephritids and their parasitoids in Kenya and Hawaii, and (4) host range testing of Psyttalia species in Kenya and Hawaii. These results are discussed in terms of their utility for predicting nontarget effects. Psyttalia concolor (SzÃ©pligeti) was shipped to Hawaii and tested against the nontarget gall forming tephritid Procecidochares utilis Stone introduced to control the weed Ageretina adenophora (Maui pamakani). Psyttalia concolor failed to attack the gall-forming P. utilis both in choice and no-choice tests, but readily attacked tephritid larvae offered in fruit in choice tests. Recommendations for further testing and release of the parasitoids from Kenya are discussed for Hawaii and Latin America. Advisors/Committee Members: Wharton, Robert A. (advisor), Harris, Marvin K. (committee member), Linton, Thomas L. (committee member), Woolley, James B. (committee member).

Subjects/Keywords: Mediterranean fruit fly; Biological Control; Nontarget Testing; Ceratitis capitata; Coffee; Parasitoids

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Trostle Duke, M. K. (2006). Classical biological control of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), (Diptera:Tephritidae): natural enemy exploration and nontarget testing. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/3877

Chicago Manual of Style (16^th Edition):

Trostle Duke, Marcia Katherine. “Classical biological control of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), (Diptera:Tephritidae): natural enemy exploration and nontarget testing.” 2006. Doctoral Dissertation, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/3877.

MLA Handbook (7^th Edition):

Trostle Duke, Marcia Katherine. “Classical biological control of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), (Diptera:Tephritidae): natural enemy exploration and nontarget testing.” 2006. Web. 03 Mar 2021.

Vancouver:

Trostle Duke MK. Classical biological control of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), (Diptera:Tephritidae): natural enemy exploration and nontarget testing. [Internet] [Doctoral dissertation]. Texas A&M University; 2006. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/3877.

Council of Science Editors:

Trostle Duke MK. Classical biological control of Mediterranean fruit fly, Ceratitis capitata (Wiedemann), (Diptera:Tephritidae): natural enemy exploration and nontarget testing. [Doctoral Dissertation]. Texas A&M University; 2006. Available from: http://hdl.handle.net/1969.1/3877

Texas A&M University

11. Calixto, Alejandro Antonio. Implications of Relative Ant Abundance and Diversity for the Management of Solenopsis Invicta Buren with Broadcast Baits.

Degree: PhD, Entomology, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2956

► Higher densities of S. invicta in the United States relative to South America are explained mainly by the absence of natural enemies and low interspecific… (more)

▼ Higher densities of S. invicta in the United States relative to South America are explained mainly by the absence of natural enemies and low interspecific competition (IC). Despite advances in S. invicta management, broadcast insecticide baits remain as the primary tool for effective control. I studied interspecific interactions of ants and the use of baits on the management of S. invicta to test the following hypotheses: 1) relative abundance of native ants increases ~25% for bait treated sites compared to untreated, 2) behavioral dominance by S. invicta decreases ~10% in bait treated sites compared to untreated, and, 3) foraging by S. invicta on insecticide baits is higher ~10% in low native ant densities areas compared to high densities. Experiments were conducted on three sites with different densities of native ants (low, medium, high), but with similar densities of S. invicta. An enhanced BACI (Before/After-Control/Impact) design was used. Experimental units consisted of 0.4 ha plots. Three treatments were randomly assigned to units and replicated four times; 1) Slow acting bait, 2) Fast acting bait, 3) Untreated Control. Samples and observations were collected for several weeks before/after the treatments to account for temporal variation and to determine rates of reinvasion. Ants were monitored using pitfalls and food lures. Interspecific competition was determined by applying placebo bait. Results indicate that different management methods did not impact resident ants when they are at low and medium densities and that S. invicta is greatly affected; at high native ant density, competition for these baits is observed affecting both natives and S. invicta. Reinvasion of S. invicta was reduced in areas of low and medium native ant densities previously treated with baits and native ant abundance increased by ~25%. At high native ant densities, reinvasion of S. invicta was similar to Control sites. I conclude: 1) properly used, baits can help in recovery of native ant species that then compete with S. invicta; however, rote re-treatments may have a negative impact on restored populations. 2) “bait failures” may be due to interspecific competition when initial native ant densities are high. Preliminary management considerations and recommendations are presented. Advisors/Committee Members: Harris, Marvin K. (advisor), Barr, Charles L. (committee member), Medina, Raul F. (committee member), Morrison, Michael L. (committee member), Vinson, Brad (committee member).

Subjects/Keywords: Filters; Competition; Bait failures; Post Oak Savannah; Central Texas; Solenopsis invicta; Resident ants

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Calixto, A. A. (2009). Implications of Relative Ant Abundance and Diversity for the Management of Solenopsis Invicta Buren with Broadcast Baits. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2956

Chicago Manual of Style (16^th Edition):

Calixto, Alejandro Antonio. “Implications of Relative Ant Abundance and Diversity for the Management of Solenopsis Invicta Buren with Broadcast Baits.” 2009. Doctoral Dissertation, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2956.

MLA Handbook (7^th Edition):

Calixto, Alejandro Antonio. “Implications of Relative Ant Abundance and Diversity for the Management of Solenopsis Invicta Buren with Broadcast Baits.” 2009. Web. 03 Mar 2021.

Vancouver:

Calixto AA. Implications of Relative Ant Abundance and Diversity for the Management of Solenopsis Invicta Buren with Broadcast Baits. [Internet] [Doctoral dissertation]. Texas A&M University; 2009. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2956.

Council of Science Editors:

Calixto AA. Implications of Relative Ant Abundance and Diversity for the Management of Solenopsis Invicta Buren with Broadcast Baits. [Doctoral Dissertation]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2956

Texas A&M University

12. Johnsen, Mark Miller. The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas.

Degree: PhD, Entomology, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-1298

► In 2002, West Nile virus was isolated for the first time in Harris County, Texas. The subsequent epidemic led the Harris County Mosquito Control Division… (more)

▼ In 2002, West Nile virus was isolated for the first time in Harris County, Texas. The subsequent epidemic led the Harris County Mosquito Control Division to initiate an extensive spraying operation to suppress infected adult mosquitoes. The control program was aimed at the predominate disease-carrying mosquito for the southern United States, Culex quinquefasciatus Say. With the increase of insecticide pressure on the mosquito populations, the possibility of resistance was brought into question. A three year study using a vial bioassay test was conducted in Harris (2004-2005) and Brazos (2005-2006) counties to determine the resistance status of Cx. quinquefasciatus to the six chemicals (malathion, naled, resmethrin, permethrin, sumithrin, and pyrethrum) used most frequently in adult mosquito control programs. The resistance ratios acquired from the vial bioassay tests were mapped onto shapefiles for Harris and Brazos counties, which revealed clustering of areas with pyrethroid resistance mosquito populations in the northeastern, southeastern, and southwestern corners of Loop 610 in Harris County. An additional six-month preliminary study, involving six operational areas in Harris County and three in Brazos County, was conducted, demonstrating only minor fluctuations in the monthly resistance ratios occurring in both counties in 2005. A significant correlation was documented between the two years of resistance ratios for mosquitoes to the three pyrethroids in Harris County and all the insecticides except pyrethrum in Brazos County. A significant relationship was also found between the resmethrin resistance ratios and the number of spray events performed during the previous year and the malathion resistance ratios with the insecticide treatments conducted in the same year. The correlation analyses provide data used to predict areas where resistance can develop in the mosquito population, thus providing the control agency more data to plan future control tactics. The overall analysis indicated that Harris County has localized pockets of resistant mosquitoes; but, on a whole, it does not seem to have widespread resistance in its mosquito populations. The only resistance that was detected was in the mosquitoes tested against the three pyrethroids. Mosquitoes in Brazos County, which has no organized mosquito control, demonstrated county-wide susceptibility to all six insecticides tested. Advisors/Committee Members: Olson, Jimmy K. (advisor), Craig, Thomas M. (committee member), Gorena, Roberto L. (committee member), Harris, Marvin K. (committee member), Russell, Leon H. (committee member).

Subjects/Keywords: Resistance; Mosquitoes

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Johnsen, M. M. (2009). The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1298

Chicago Manual of Style (16^th Edition):

Johnsen, Mark Miller. “The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas.” 2009. Doctoral Dissertation, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-1298.

MLA Handbook (7^th Edition):

Johnsen, Mark Miller. “The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas.” 2009. Web. 03 Mar 2021.

Vancouver:

Johnsen MM. The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas. [Internet] [Doctoral dissertation]. Texas A&M University; 2009. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1298.

Council of Science Editors:

Johnsen MM. The status of resistance in Culex quinquefasciatus say (Diptera: culicidae) populations in Brazos and Harris Counties, Texas. [Doctoral Dissertation]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1298

Texas A&M University

13. Gorena, Roberto Luis. Characterization of Schizaphis graminum (Rondani) (Homoptera: Aphididae) biotype evolution via virulence and fitness on Sorghum bicolor (L.) Moench and Sorghum halepense (L.) Persoon.

Degree: PhD, Entomology, 2004, Texas A&M University

URL: http://hdl.handle.net/1969.1/63

► Greenbug is one of two key insect pests of sorghum, and biotype evolution hinders the long-term usefulness of resistant sorghums. The current study sought to… (more)

▼ Greenbug is one of two key insect pests of sorghum, and biotype evolution hinders the long-term usefulness of resistant sorghums. The current study sought to identify plant resistance mechanisms, plant damage characteristics, and greenbug fitness in sorghum/greenbug interactions. Choice tests were conducted to elucidate resistance mechanisms displayed by four sorghum genotypes towards several greenbug biotypes and isolates. Results indicated all three resistance modalities (antibiosis, antixenosis, tolerance) were identified in sorghums, with some genotypes displaying two or more modalities towards some biotypes. This suggests some sorghum genotypes do not select for greenbug biotypes, and the sorghum genotypes cultivated may have relatively long-term resistance. Non-choice tests were used to determine plant damage associated with greenbug feeding. Four sorghum genotype, Johnson grass, and five greenbug biotype combinations were used to elucidate plant characteristics associated with visible plant damage. Fluid loss and plant stunting were significantly associated with visible plant damage, and were also observed in some plants not incurring heavy visible damage. Additionally, some biotypes avirulent to cultivated sorghum caused significant damage to Johnson grass. These results suggest visible plant damage, routinely used in damage studies, reflects underlying causes that could lead to poor agronomic performance. Additionally, Johnson grass may harbor greenbug biotypes not commonly found in sorghum fields. Greenbug colony and individual fitness were determined by reproduction rates of five biotypes on four sorghum genotypes and Johnson grass in non-choice tests. Generally, colony and individual fitness estimates were not different within genotype/biotype combinations. Also, biotypes did best on more susceptible and worst on more resistant sorghum genotypes. Colonies and individuals of all biotypes had lowest fitness on Johnson grass. These results suggest virulent biotypes may have a fitness advantage over avirulent ones, at least in the presence of the cultivated host. The results presented herein reflect the diversity of sorghum/greenbug interactions, and underscore the need for further understanding of the nature of greenbug biotypes, and how they interact with cultivated and non-cultivated host plants. Advisors/Committee Members: Harris, Marvin K. (advisor), Peterson, Gary C. (advisor), Burd, John D. (committee member), Woolley, James B. (committee member), Bernal, Julio S. (committee member).

Subjects/Keywords: greenbug; sorghum; insect-plant interactions; biotypes

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gorena, R. L. (2004). Characterization of Schizaphis graminum (Rondani) (Homoptera: Aphididae) biotype evolution via virulence and fitness on Sorghum bicolor (L.) Moench and Sorghum halepense (L.) Persoon. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/63

Chicago Manual of Style (16^th Edition):

Gorena, Roberto Luis. “Characterization of Schizaphis graminum (Rondani) (Homoptera: Aphididae) biotype evolution via virulence and fitness on Sorghum bicolor (L.) Moench and Sorghum halepense (L.) Persoon.” 2004. Doctoral Dissertation, Texas A&M University. Accessed March 03, 2021. http://hdl.handle.net/1969.1/63.

MLA Handbook (7^th Edition):

Gorena, Roberto Luis. “Characterization of Schizaphis graminum (Rondani) (Homoptera: Aphididae) biotype evolution via virulence and fitness on Sorghum bicolor (L.) Moench and Sorghum halepense (L.) Persoon.” 2004. Web. 03 Mar 2021.

Vancouver:

Gorena RL. Characterization of Schizaphis graminum (Rondani) (Homoptera: Aphididae) biotype evolution via virulence and fitness on Sorghum bicolor (L.) Moench and Sorghum halepense (L.) Persoon. [Internet] [Doctoral dissertation]. Texas A&M University; 2004. [cited 2021 Mar 03]. Available from: http://hdl.handle.net/1969.1/63.

Council of Science Editors:

Gorena RL. Characterization of Schizaphis graminum (Rondani) (Homoptera: Aphididae) biotype evolution via virulence and fitness on Sorghum bicolor (L.) Moench and Sorghum halepense (L.) Persoon. [Doctoral Dissertation]. Texas A&M University; 2004. Available from: http://hdl.handle.net/1969.1/63

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