Long-term heat stress (HS) induced by testicular insulation generates oxidative stress (OS) on the testicular environment; consequently activating antioxidant enzymes such as superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GPx). The aim of this work was to immunolocalize antioxidant enzymes present in different cells within the seminiferous tubule when rams were submitted to HS. Rams were divided into control (n = 6) and treated group (n = 6), comprising rams subjected to testicular insulation for 240 h. After the testicular insulation period, rams were subjected to orchiectomy. Testicular fragments were submitted to immunohistochemistry for staining against SOD, GR and GPx enzymes. We observed immunolocalization of GPx in more cell types of the testis after HS and when compared with other enzymes. In conclusion, GPx is the main antioxidant enzyme identified in testicular cells in an attempt to maintain oxidative balance when HS occurs.

Tropical signalgrass (TSG) causes serious problems for sod production and turf maintenance in Florida. Other grasses such as large crabgrass (CG), smutgrass (SG), thin paspalum (TP), and torpedograss (TG) can be problematic as well. Several emulsion formulations composed of mycelium or mycelium-free culture filtrate (or both) of the fungal pathogen Drechslera gigantea (DG) and Sunspray 6E oil were tested with or without ammonium sulfate or pelargonic acid (n-nonanoic acid; a natural product registered as a biorational herbicide) in greenhouse and field trials. A 30% Sunspray 6E oil formulation containing DG mycelium (10 g), DG culture filtrate (70 ml), and 4.5 g of ammonium sulfate caused 88 to 100% injury on TSG, CG, SG, and TG in greenhouse trials. The injury resulted from disease as well as phytotoxicity of the culture filtrate, oil, and ammonium sulfate. An emulsion formulation composed of 30% Sunspray 6E oil and 70% DG culture filtrate amended with 2% (v/v) pelargonic acid killed SG 2 wk after application. DG formulations containing ammonium sulfate or pelargonic acid produced lower levels of injury when treated grasses were exposed to a 24-h dew period compared with those treated and not exposed to dew. Formulations containing DG mycelium, DG culture filtrate, and ammonium sulfate or pelargonic acid are effective and promising for control of weedy grasses. Further evaluations of these formulations under field conditions are justified.

Acetolactate synthase (ALS) inhibitors are widely used for POST control of sedges in turfgrass. A suspected resistant (R) biotype of annual sedge was collected from a bermudagrass turf in Georgia with a history of exclusive use of halosulfuron. Research was conducted to evaluate the resistance level of this biotype to halosulfuron, efficacy of ALS-inhibiting herbicides and other mechanisms of action for control, and the molecular and physiological basis for resistance. In greenhouse experiments, the halosulfuron rate required to reduce shoot biomass 50% in comparison with the nontreated at 8 wk after treatment (WAT) were 8 and > 1,120 g ai ha−1 for the S (susceptible) and R biotypes, respectively. Imazapic, sulfosulfuron, and trifloxysulfuron reduced biomass of the S biotype greater than 60% at 8 WAT, but biomass was reduced less than 20% for the R biotype. Glufosinate, glyphosate, MSMA, and sulfentrazone reduced shoot biomass of the R biotype by 93, 86, 97, and 45%, respectively. In laboratory experiments, the halosulfuron concentration required to inhibit ALS activity by 50% in excised leaf tissues was 5.8 and > 1,000 μM for the S and R biotypes, respectively. Gene sequencing of the R biotype revealed a Pro-197-Ser substitution that confers resistance to ALS inhibitors. This is the first report of ALS-inhibitor resistance in annual sedge and herbicide resistance in a sedge species from a turfgrass system.

Oocysts of Cryptosporidium parvum showed relatively low levels of SOD activity. The SOD which had a pI of 4.8 and an approximate molecular weight of 35 kDa appeared to be iron dependent. Catalase, glutathione transferase, glutathione reductase and glutathione peroxidase activity could not be detected, nor could trypanothione reductase. No NADH or NADPH oxidase activity could be detected, nor could peroxidase activity be demonstrated using o-dianisidine, guaiacol, NADPH or NADH as co-substrates. However, an NADPH-dependent H2O2 scavenging system was detected in the insoluble fraction.

The U.S. public is expressing strong preference for the use of biological control methods in the management of U.S. agricultural, forest, and rangeland insect pests. This follows from a widespread understanding among citizens that synthetic insecticides have potentially harmful side effects on humans and that they are spreading increasingly as pollutants in the environment. Major recent increases in the number of pesticide-resistant insect species also put pressure on the agricultural community toward adoption of alternative non-agchemical plant and animal protection strategies. Movement in the direction of such alternatives has been facilitated by the fact that in the last two decades much progress has been made in Integrated Pest Management (IPM) through an improved understanding of the interactions of pests with their hosts. In that time period, many advances have been made in describing and predicting insect movement, seasonal cycles, and the effects of secondary plant compounds on insect reproduction. Simultaneously, much has been learned about the behavior, physiology, and population dynamics of insect parasitoids, i.e. parasites on insect pests. In the 1990's and subsequently, Biological Control Intensive Pest Management (BCIPM) will require continuing research to attain needed advancement in knowledge of growth and development of host plants, population dynamics of pests and parasitoids, and ecology of secondary pests that may interfere with implementation of BCIPM programs. Extension and research personnel will then be increasingly able to devise useful control methods for pests within selected cropping systems. We describe here examples to illustrate present and potential future use of BCIPM in different practical plant systems in New Jersey.