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In 1998, following the very wet EI Niño weather event, a devastating outbreak of rust disease severely damaged the garlic crop in California. The disease also occurred in 1999 and 2000, indicating that rust may have developed into an annual problem. We identified the pathogen as Puccinia allii. In our study, it infected allium crops such as garlic, onion and chives, but not leek, elephant garlic or shallot. Currently registered materials did not control the disease, but tebuconazole (Folicur) and azoxystrobin (Quadris) provided good protection against garlic rust. Based on our work, a Section 18 emergency exomption for tebuconazole was approved by state pesticide regulators. We tested 34 UC and industry garlic varieties and found that none were completely resistant to garlic rust.

Children in foster care largely believe that placement is beneficial to them as they escape the abuse and neglect of their families. However, interviews with 11- to 14-year-old foster children indicate that many are not too clear about the circumstances of the placement. They consider that their situation can be further improved if there is an emphasis on increasing the flow and quality of information among children, biological parents, foster parents and caseworkers.

As part of a continuing survey, effluents from five mills in Canada were tested in the laboratory for their potential to affect fish reproduction. The study included effluents from two thermomechanical pulp (TMP) mills, two kraft pulp mills, and one mill that used both chemical and mechanical pulping. The laboratory test used adult fathead minnows and involved a 21-day exposure to each effluent. All the effluents were tested at 2 and 20% concentration. The effluent from 1 of the kraft mills was also tested at 40% concentration. The endpoints of the test included, egg production, gonad size, sex steroids, secondary sexual characteristics, and vitellogenin concentration in males, considered to be an indicator of estrogenicity. The results of this study were similar to the results of our previous survey. None of the effluents produced noteworthy changes at 2% concentration. At 20% concentration, only the effluent from the multiprocess mill produced a significant reduction in eggs, which was considered to be the most important indicator of reproductive performance. Some effluents did produce an increase and/or a decrease in a variety of endpoints other than egg production, but the most consistent response was an induction of vitellogenin in males exposed to three of the five effluents tested. In summary, these results indicate that most mill effluents up to 20 or 40% concentration do not affect the overall reproductive capacity of minnows in the laboratory. However, the mill effluents do seem to contain substances that cause vitellogenin induction. [ABSTRACT FROM AUTHOR]

In Canada, effluents from pulp and paper mills are regulated for toxicity. The regulation requires ≤50% survival of rainbow trout (Oncorhynchus mykiss) exposed to full-strength (i.e., 100%) effluent for 96 h in tests that must be conducted monthly. The regulation also calls for ≥50% survival of Daphnia magna exposed to 100% effluent for 48 h in weekly monitoring tests. Every year, about 10 to 25% of the mills exceed the regulatory limit at least once in tests with either rainbow trout or Daphnia magna. Between 1996 and 2003, we investigated 84 such cases from 32 mills. Of the 84 investigations, 49 involved only trout, 29 involved only Daphnia, and six involved both species. We identified the actual cause of toxicity in 70% of the cases and partially or tentatively identified the toxicant(s) in 17% more. In the cases involving only trout, the most frequent causes of toxicity were related to biotreatment performance (e.g., ammonia). In the cases involving only Daphnia, the most frequent cause of toxicity seemed to be related to polymeric formulations. For those cases involving both trout and Daphnia, the cause of toxicity was traced to more than one compound or to excess concentrations of a specific compound resulting from a spill or biotreatment-related problems. [ABSTRACT FROM AUTHOR]

A questionnaire was sent to 75 mills in Canada requesting information on compliance in 1999 with respect to the toxicity regulation for liquid discharges. This regulation requires that at least 50% of rainbow trout and Daphnia magna survive in the discharge from the mill in toxicity tests. Of the 74 mills that responded, 81% and 74% reported no toxicity failures for process effluents in rainbow trout and Daphnia magna tests, respectively. For mills with infrequent or no toxicity episodes during the year (1 or 0 for trout; 1-4 or 0 for Daphnia magna), 89% and 92% of the mills met this criterion for trout and Daphnia magna tests, respectively. In addition to process effluents, 28 mills had separate cooling water discharges and, of these, ten experienced at least one episode of cooling water toxicity. Ammonia and accidental spills were most frequently cited by the mills as likely causes of process effluent toxicity. The most frequent causes cited for cooling water toxicity were chlorine and accidental contamination from other sources. [ABSTRACT FROM AUTHOR]

In 1998, a devastating outbreak of rust disease severely damaged the garlic crop in California, resulting in yield losses of 51% and an economic loss of 27% to the industry. The disease also occurred in 1999 and 2000, indicating that rust may have become an annual problem in some parts of the state. The presence of urediniospores, two-celled teliospores, and telial paraphyses indicated that the pathogen was Puccinia allii. Isolates from garlic infected onion and chives, but not leek, elephant garlic, or shallot in inoculation experiments. Garlic cloves obtained from diseased plants were planted under controlled conditions, but the resulting plants did not develop rust. Fungicide trials were conducted for 3 years and showed that none of the currently registered materials gave satisfactory control. However, tebuconazole and azoxystrobin provided good protection against rust if sprayed at 10-day intervals. A variety trial of 34 garlic cultivars and selections was planted, inoculated, and evaluated for resistance to rust. Although there was variability in rust severity among the selections, acceptable levels of resistance were not observed in any cultivar.