Association of Spring Pruning Practices with Severity of Powdery Mildew and Downy Mildew on Hop.

Downy mildew (caused by Pseudoperonospora humuli) and powdery mildew (caused by Podosphaera macularis) are important diseases of hop in the Pacific Northwest United States, and cultural practices may affect the severity of both diseases. The association of spring pruning quality and timing with severity of downy mildew and powdery mildew was assessed through analysis of survey data collected from commercial hop yards in Oregon and Washington. Among 149 hop yards surveyed, the most common pruning method was chemical desiccation (48% of yards), mechanical pruning (23%), or a combination of these practices (15%).

Sarcoids in captive zebras (Equus burchellii): association with bovine papillomavirus type 1 infection.

Sarcoids were diagnosed in two captive zebras from different facilities. Zebra 1 (Equus burchellii boehmi) was a 4.5-yr-old, captive-born male that presented with a 9- by 7-cm inguinal mass.

Effect of Registered Potato Seed Piece Fungicides on Tuber-borne Phytophthora infestans.

Curative applications of thiophanate-methyl + mancozeb to blighted seed pieces of three potato (Solanum tuberosum) cultivars significantly reduced the amount of surface area colonized by Phytophthora infestans compared with treatment with thiophanate-methyl or no fungicide under laboratory conditions. Percent blighted tuber surface area over six tests averaged 3.5, 11.

Joint analysis of site-specific cancer risks for the atomic bomb survivors.

Statistical methods are presented for joint analysis of site-specific cancer risks for the atomic bomb survivors. Previous analyses of these data have been made either without regard to cancer type, excluding leukemia, or separately for types or classes of cancers. Clearly, analyses without regard to cancer type are less than satisfactory.

ras and neu oncogenes reverse serum inhibition and epidermal growth factor dependence of serum-free mouse embryo cells.

Serum-free mouse embryo cells, cultured in basal nutrient medium supplemented with insulin, transferrin, epidermal growth factor, fibronectin, and high-density lipoprotein, do not exhibit growth crisis, lack detectable chromosomal aberrations, are nontumorigenic in vivo, are dependent on epidermal growth factor for survival, and are growth inhibited by serum or platelet-free plasma. These cells after transfection with the human Ha-ras or rat neu oncogenes no longer required epidermal growth factor for survival, were tumorigenic in vivo, and also proliferated in serum-containing medium. Autocrine activity capable of replacing epidermal growth factor was detected in conditioned medium from ras-transformed cultures, but little such activity was detected in medium from neu-transformed cultures.