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Species of Colletotrichum, Botryosphaeria, and Phomopsis causing postharvest rots in avocado (Persea americana Miller) fruits are present in the living and dead branches and twigs of avocado trees, and in the living pedicels. They dominate the fungal population within the extra-cambial tissues but are less common within the xylem elements. There is no evidence that invasion of these tissues is pathogenic. With the possible exception of C. gloeosporioides they appear to be discontinuously present and are more properly termed phellophytes rather than endophytes. There was a higher incidence of stem-end rots than of body rots in untreated (control) 'Hass' avocados in New Zealand experiments and most of these stem-end rots were associated with B. parva and Phomopsis spp. A high proportion of stem-end infections appeared to be initiated during harvesting. Picking the fruit by snapping the pedicels instead of clipping, as in commercial practice, resulted in an unusually high level of stem-end rots caused by C. acutatum. Frequently sterilising the clippers used to harvest the fruits reduced the incidence of stem-end infections, in particular those caused by B. parva, indicating that contamination of the clippers is an important source of infection. It is suggested that this contamination is probably present as fragments of infected extra-cambial tissue.

A disease complex, with symptoms that include stem cankers and tip die-back, is reported in New Zealand olives (Olea europaea L.). Bacteria from stem cankers of olive were consistently isolated as pale lemon-yellow colonies on King's medium B. On the basis of microbiological, molecular, and pathogenicity tests the bacterium isolated was identified as Xanthomonas sp. The bacterial isolates allowed verification of Koch's postulates on young olive trees. As a result of our findings we suggest that the stem canker on olive is caused by Xanthomonas sp. In addition a fungus identified as Fusicoccum luteum was consistently isolated from stem cankers and tip die-back. In inoculated plants F. luteum occasionally formed cankerous symptoms though not as aggressively as Xanthomonas sp. At this stage it is not clear what role F. luteum has in primary infection.

Compendium of tropical fruit diseases. Edited by R. C. Ploetz; G. A. Zentmyer; W.t Nishijima; K. G. Rohrbach; and H. D. Ohr. Published in 1994 by APS Press, St Paul, Minnesota, United States. 88 + vii p. + 30 p. colour plates. ISBN 0-89054-162-0. Price: US$30.00 (United States); US$37.00 (elsewhere).Principles of cereal science and technology. 2nd edition. Edited by R. Carl Hoseney. Published in 1993 by the American Association of Cereal Chemists, StPaul, Minnesota, United States. 374p., hardcover. ISBN 0-913250-79-1. Price: US$79.00 (plus US$2.00 postage) (United States); US$95.00 (incl. p. & p.) (elsewhere).Pre-harvest sprouting in cereals. Edited by M. K. Walker-Simmons and J. L. Ried. Published in 1993 by American Association of Cereal Chemists, St Paul, Minnesota, United States. 480 p., softcover. ISBN 0-913250-81-3. Price: US$59 + $2 postage (United States); US$71 incl. p & p (elsewhere).Legumes—the Australian experience. By B. R. Davidson and H. F. Davidson. Published in 1993 by Research Studies Press Ltd, Taunton, Somerset, England. ISBN 0-86380-146-3. Price £75.00.Defining soil quality for a sustainable environment. Edited by J. W. Doran; D. C. Coleman; D. F. Bezdicek; and B. A. Stewart. Published in 1994 by Soil Science Society of America, American Society of Agronomy, Madison, Wisconsin, United States. 244 p. ISBN 0-89118-807-X. Price: US$33.00 (incl. p.&p.).

An analytical study has been performed to investigate the performance and application of four exhaust nozzle concepts with the potential to enhance the short takeoff and landing capabilities of advanced tactical aircraft for the 1990s. The exhaust system concepts include side and rear exhaust thrust vectoring systems with axisymmetric and nonaxisymmetric nozzles. To investigate the application of the nozzle concepts, advanced tactical aircraft have been configured which will operate from 700 or 1000 feet fields. Four different propulsion system configurations were used, each producing glide slope equilibrium in a different way. The characteristics of these STOL aircraft are compared with those of a CTOL aircraft designed to perform the same mission. The results show that the short field performance can be achieved with little aircraft TOGW or LCC penalty. The study also identifies promising configurations for STOL tactical aircraft.

AbstractThe time required for potato late blight lesions, caused by Phytophthora infestans(Mont.) de Bary, to produce sporangia during periods of continuous leaf wetness, and for inoculations to produce lesions bearing sporangia, was determined over a temperature range of 5–24°C. Equations were derived relating time to sporulate with temperature. A 2-h break in leaf wetness, initiated at any time within the first 3 h of incubation after inoculation, markedly reduced lesion numbers. When the break was initiated later it had less effect, except at the lowest temperature tested (9°C).

Crops and man. Second edition. By Jack R. Harlan. Published in 1992 by the American Society of Agronomy, Inc. and the Crop Science Society of America, Inc. Madison, Wisconsin, United States, xiii + 284 p., hardcover. ISBN 0-89118-107-5. Price: US$34.00.Barley: genetics, biochemistry, molecular biology and biotechnology. Edited by P. R. Shewry. Published in 1992 by CAB International, Wallingford, United Kingdom. 624 p., hardback. ISBN 0-85198-725-7. Price: £75.00.Methods for research on soilborne phytopathogenic fungi. Edited by L.L. Singleton, J.D. Mihail, and CM. Rush. Published in 1992 by APS Press, St Paul, Minnesota, United States. 265 p., spiral bound. ISBN 0-89054-127-2. Price: US$42.00 (incl. p&p).Biological and cultural tests for control of plant diseases. Volume 7. Edited by David S. Wysong. Published in 1992 by APS Press, St Paul, Minnesota, United States. 137 p., soft bound. ISSN 0887-2236. Price US$31 (incl. p&p).Managing diseases in greenhouse crops. By William R. Jarvis. Published in 1992 by APS Press, St. Paul, Minnesota., United States, vii + 288 p., 41 figs, 27 plates & 35 tables, hardback. ISBN 0-89054-122-1. Price: US$79.00 (United States); US$99.00 (elsewhere) (incl. p & p).

Several letters to the editor are presented in response to articles in previous issues including "Shocker," on the September 3, 2011 issue, "Art," by Megan Dunn on the August 27, 2011 issue and "Our cup runneth over" on the September 3, 2011 issue.