133 research outputs found
Inquiry-Based Science Communication Using Plant and Animal Systems
Programs:
Our Zoo to YOU: Unique partnership: Nebraska Schools, science educators, scientists, and the Lincoln Children’s Zoo. To provide elementary and middle school educators with a unique opportunity to teach inquiry-based science with live animals. Focus on both teachers and students
Soybeans in the Classroom Research Experience for Teachers--Transformative model of education and professional development focused on: • Systems-approach • Science as inquiry • Integration of agricultural systems as vehicles for science education
Science as Inquir
UNL Life Sciences Initiative
The Life Sciences curriculum consists of a two semester series of courses and associated laboratories covering the fundamentals of biology. It is intended to serve those students who intend on taking more advanced biology courses. We will discuss the development and implementation of the new life courses and laboratories
Host preference of the chinch bug, \u3ci\u3eBlissus occiduus\u3c/i\u3e
The chinch bug, Blissus occiduus Barber (Hemiptera: Blissidae), is an important pest of buffalograss, Buchloë dactyloides (Nutall) Engelmann and potentially other turfgrass, crop, and non-crop hosts. Choice studies documented the number of B. occiduus present on selected turfgrasses, crops and weeds, and provided important insights into the host preferences of this chinch bug. Grasses with the most chinch bugs present included the warm-season turfgrasses B. dactyloides, zoysiagrass, Zoysia japonica Steudel, bermudagrass, Cynodon dactylon (L.) Pers., and St. Augustinegrass , Stenotaphrum secundatum (Walt.) Kuntze. The other grasses tested, green foxtail, Setaria viridis (L.) Beauv, Kentucky bluegrass, Poa pratensis L., perennial ryegrass, Lolium perenne L., rye, Secale cereale L., sorghum, Sorghum bicolor (L.) Moench, tall fescue, Festuca arundinacea Schreb. and wheat Tritium aestivum L. had significantly fewer chinch bugs. Buffalograss and zoysiagrass had the highest numbers of chinch bugs among the warm-season grasses and the buffalograss cultivars ‘86-120’ and ‘PX-3-5-1’ had more chinch bugs than the zoysiagrass cultivars ‘Meyers’ and ‘El Toro’ after the two hour evaluation time
Z B Mayo, Jr. Obituary
Emeritus Professor of Entomology at University of Nebraska–Lincoln, Dr. Z B Mayo, Jr., passed away on 25 March 2018 in Lincoln, Nebraska.
Employed at the University of Nebraska– Lincoln (UNL) from 1972 to 2010, he had a distinguished career as a researcher, teacher, mentor, and administrator. From 1972 to 1985, he conducted research on insects associated with corn production in Nebraska, with a major emphasis placed on the biology and control of corn rootworms. He and his students contributed significantly to our knowledge of corn rootworm biology and management. In 1983, he took a professional development leave and worked at the USDA-ARS Plant Science Research Lab at Stillwater, Oklahoma, conducting fundamental research on aphid biotypes. From 1985 on, he redirected his research program to study the development of bio-intensive pest management programs for field crops, particularly grain sorghum. His research topics included interactions of biological control with aphid-resistant cultivars and insecticide-resistant aphids, and genetic and environmental factors influencing the development of aphid biotypes and insecticide resistance. He authored 41 refereed journal articles, 3 book chapters, and numerous extension and popular articles. He was major advisor for seven Ph.D. and eight M.S. students, served on the supervisory committees of 32 Ph.D. and 40 M.S. students, and supervised three postdoctoral scientists
Evaluation of Warm-season Turfgrasses for Resistance to the Chinch Bug, \u3ci\u3eBlissus occiduus\u3c/i\u3e
The chinch bug, Blissus occiduus Barber, has been documented as a serious pest of buffalograss, Buchloë dactyloides (Nutall) Engelmann, and zoysiagrass, Zoysia japonica Steudel, turf grown in the Midwest. In addition to these two warm-season turfgrasses, several other warm-season grasses, including bermudagrass, Cynodon dactylon (L.) Pers., may also be at risk of B. occiduus infestations. This research evaluated selected bermudagrass and zoysiagrass cultivars for resistance to B. occiduus. Eleven zoysiagrass and four bermudagrass cultivars were evaluated for resistance to B. occiduus using no-choice studies under greenhouse conditions. Based on turfgrass damage ratings, the zoysiagrasses ‘Diamond’, ‘Zoro’, and ‘Emerald’, and bermudagrass ‘Mini Verde’ were identified as moderately resistant to B. occiduus. The zoysiagrasses ‘Zenith’, ‘Meyer’, and ‘Crowne’, and bermudagrasses ‘Tifway 419’ and ‘Tifsport’’ were characterized as highly to moderately susceptible to B. occiduus. These results provide the first report of resistance to B. occiduus in zoysiagrass and bermudagrass germplasm
Beneficial Arthropods Associated with Buffalograss
Beneficial arthropods collected from buffalograss, Buchloe dactyloides (Nuttall) Engelmann, evaluation plots and vegetatively established buffalograss lawns included predatory ants, spiders, ground beetles, rove beetles, big-eyed.bugs, and several species of hymenopterous parasitoids. Ants and spiders were the most abundant beneficial arthropods collected, representing 84% of the total beneficial arthropods captured. Pitfall traps collected \u3e2.5 times as many (16,094) beneficial arthropods as sod plug samples (6,054), demonstrating that pitfall traps are a more effective technique than sod plugs for capturing highly mobile surface-dwelling arthropods. Families of parasitoids captured on sticky traps during the 2-yr sampling period included Scelionidae, Encyrtidae, Mymaridae, and Trichogrammatidae. Mymarids and trichogrammatids were the most abundant parasitoid families, representing 76.8% of the total parasitoids collected. Total numbers of beneficial arthropods collected from sites maintained at higher and lower management levels were not significantly different, suggesting that beneficial arthropod abundance may not be adversely affected by the 2 management regimes applied in this study
Beneficial Arthropods Associated with Buffalograss
Beneficial arthropods collected from buffalograss, Buchloe dactyloides (Nuttall) Engelmann, evaluation plots and vegetatively established buffalograss lawns included predatory ants, spiders, ground beetles, rove beetles, big-eyed.bugs, and several species of hymenopterous parasitoids. Ants and spiders were the most abundant beneficial arthropods collected, representing 84% of the total beneficial arthropods captured. Pitfall traps collected \u3e2.5 times as many (16,094) beneficial arthropods as sod plug samples (6,054), demonstrating that pitfall traps are a more effective technique than sod plugs for capturing highly mobile surface-dwelling arthropods. Families of parasitoids captured on sticky traps during the 2-yr sampling period included Scelionidae, Encyrtidae, Mymaridae, and Trichogrammatidae. Mymarids and trichogrammatids were the most abundant parasitoid families, representing 76.8% of the total parasitoids collected. Total numbers of beneficial arthropods collected from sites maintained at higher and lower management levels were not significantly different, suggesting that beneficial arthropod abundance may not be adversely affected by the 2 management regimes applied in this study
Fall armyworm (Spodoptera frugiperda Smith) feeding elicits differential defense responses in upland and lowland switchgrass
Switchgrass (Panicum virgatum L.) is a low input, high biomass perennial grass being developed for the bioenergy sector. Upland and lowland cultivars can differ in their responses to insect herbivory. Fall armyworm [FAW; Spodoptera frugiperda JE Smith (Lepidoptera: Noctuidae)] is a generalist pest of many plant species and can feed on switchgrass as well. Here, in two different trials, FAW larval mass were significantly reduced when fed on lowland cultivar Kanlow relative to larvae fed on upland cultivar Summer plants after 10 days. Hormone content of plants indicated elevated levels of the plant defense hormone jasmonic acid (JA) and its bioactive conjugate JA-Ile although significant differences were not observed. Conversely, the precursor to JA, 12-oxo-phytodienoic acid (OPDA) levels were significantly different between FAW fed Summer and Kanlow plants raising the possibility of differential signaling by OPDA in the two cultivars. Global transcriptome analysis revealed a stronger response in Kanlow plant relative to Summer plants. Among these changes were a preferential upregulation of several branches of terpenoid and phenylpropanoid biosynthesis in Kanlow plants suggesting that enhanced biosynthesis or accumulation of antifeedants could have negatively impacted FAW larval mass gain on Kanlow plants relative to Summer plants. A comparison of the switchgrass-FAW RNA-Seq dataset to those from maize-FAW and switchgrass-aphid interactions revealed that key components of plant responses to herbivory, including induction of JA biosynthesis, key transcription factors and JA-inducible genes were apparently conserved in switchgrass and maize. In addition, these data affirm earlier studies with FAW and aphids that the cultivar Kanlow can provide useful genetics for the breeding of switchgrass germplasm with improved insect resistance
Plant Tolerance: A Unique Approach to Control Hemipteran Pests
Plant tolerance to insect pests has been indicated to be a unique category of resistance, however, very little information is available on the mechanism of tolerance against insect pests. Tolerance is distinctive in terms of the plant’s ability to withstand or recover from herbivore injury through growth and compensatory physiological processes. Because plant tolerance involves plant compensatory characteristics, the plant is able to harbor large numbers of herbivores without interfering with the insect pest’s physiology or behavior. Some studies have observed that tolerant plants can compensate photosynthetically by avoiding feedback inhibition and impaired electron flow through photosystem II that occurs as a result of insect feeding. Similarly, the up-regulation of peroxidases and other oxidative enzymes during insect feeding, in conjunction with elevated levels of phytohormones can play an important role in providing plant tolerance to insect pests. Hemipteran insects comprise some of the most economically important plant pests (e.g., aphids, whiteflies), due to their ability to achieve high population growth and their potential to transmit plant viruses. In this review, results from studies on plant tolerance to hemipterans are summarized, and potential models to understand tolerance are presented
Influence of \u3ci\u3eRhopus nigroclavatus\u3c/i\u3e (Hymenoptera: Encyrtidae) on the Mealybugs \u3ci\u3eTridiscus sporoboli\u3c/i\u3e and \u3ci\u3eTrionymus\u3c/i\u3e sp. (Homoptera: Pseudococcidae)
This research investigated parasitism of the buffalograss mealybugs Tridiscus sporoboli (Cockerell) and Trionymus sp. by Rhopus nigroclavatus (Ashmead) through rearing and dissection studies, paired comparison tests, and a field survey. Rates of parasitism reported in this article reflect combined parasitism of the 2 mealybug species. In the rearing study, parasitism of adult female mealybugs by R. nigroclavatus was 48.6%, with an average emergence of 1.77 parasitoids per parasitized mealybug. A maximum of 7 R. nigroclavatus adults emerged from a single mealybug female. Mealybug dissections documented parasitism rates by R. nigroclavatus of 78.5, 67.5, and 4.3%, respectively, for adult females, 3rd and 4th (male pupae) instars, and 1st- and 2nd-instar mealybugs. Results revealed the preference of R. nigroclavatus for adult female mealybugs and later instars, and suggested a potential regulating effect of R. nigroclavatus on buffalograss mealybug populations. Paired comparison tests with and without R. nigroclavatus demonstrated the effectiveness of this parasitoid as a biological control agent for buffalograss mealybugs under greenhouse conditions. Significant differences were detected in the number of nonparasitized mealybugs between treatments containing only mealybugs and treatments containing both mealybugs and parasitoids. Sticky trap captures in the field suggested a functional relationship between the seasonal abundance of R. nigroclavatus and its mealybug hosts
- …