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Sclerotinia blight, caused by Sclerotinia sclerotiorum is reported from Quang Nam Province, Vietnam, for the first time. The disease is common in cool wet winter and spring seasons on dwarf and climbing beans, peanuts and occasionally on chilli plants. A serious epidemic occurred in peanuts in some communes in spring 2008, following a period of cool wet weather after the crop canopy had closed and when flowering was well advanced.

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This is the first report of Pythium root rot of chrysanthemum, and the pathogen responsible, Pythium aphanidermatum, from Quang Nam and TT Hue Provinces in Vietnam. The typical symptoms included stunting, wilting, and necrosis of the main, lateral and feeder rootlets. A black necrotic lesion girdling the lower stem was present in some diseased plants. The root rot commonly caused death of diseased plants and affected plants at all growth stages. The pathogen was also isolated from transplants affected by root rot, and sampled directly from boxes transported from Dalat, Lam Dong Province, the source of most transplants used in Quang Nam. Metalaxyl was shown to provide effective control of Pythium root rot in a field trial when used to dip transplants before planting, and as a regular drench. Metalaxyl also provided effective control of the disease in commercial crops on the farm where the field was located.

Typical symptoms of pink root rot were observed in Chinese onions in Quang Nam and Nghe An provinces in Vietnam in 2007. The pathogen recognised as the cause of pink root rot in onions, Phoma terrestris, was isolated from diseased roots. This is the first report of pink root rot and P. terrestris in Vietnam.

The paper reports soil seedbank species composition, of Eucalyptus victrix grassy woodlands, of the upper Fortescue River in the Pilbara District, Western Australia. In this study, our objectives were to investigate germinable soil seedbanks and species composition in response to three simulated seasons, using emergence. Variation in seed density from three depths was tested. Four field sites were sampled. Thirty samples were collected in late spring, after seed rain and before summer rainfall. From each sample spot, three soil depths (surface, 1–5, and 6–10 cm) were segregated from beneath surface areas of 100 cm2. Samples were later incubated in a glasshouse to simulate three different seasonal conditions (autumn, winter and spring). Germinating seedlings were recorded on emergence and grown until identified. Forty-one species germinated, comprising 11 grasses (7 annuals and 4 perennials), 25 annual herbs and 5 perennial herbs. Distribution patterns of germinable seed in both the important annual grass Eragrostis japonica and the perennial Eragrostis setifolia (a preferred cattle fodder species), suggest that seedbank accumulation differs among species and between sites. In part, this may be associated with the absence of grazing. Species with most total germinable seed were E. japonica (Poaceae; 603/m2), and the annual herbs Calotis multicaulis (Asteraceae; 346/m2), and Mimulus gracilis (Scrophulariaceae; 168/m2). Perennial grass seed was sparse. Spring simulation gave most germination (1059), followed by autumn (892) and winter (376) sets. Greatest species diversity was produced from the spring simulation (33 species), followed by autumn (26), and winter (22). Of the total germination, 92% came from 17 species that were represented in all three simulations. Of the 1227 grass seedlings counted, most were recruited from the surface soil (735), followed by the 5 (310) and 10 (182) cm depths. Marginally more grass seedlings germinated from the spring simulation (558) than the autumn set (523). Only 11.9% of grass germinants came from the winter simulation. All grass species recruited from the soil seedbanks had a C4 photosynthetic pathway. Except for Cenchrus ciliaris all grass species are native to Australia. Of the four sites sampled, one fenced to exclude cattle five years earlier had significantly more germination than the three unfenced sites. Seedbank sampling produced several new records for plants in the areas sampled.

Summary In this study, we aimed to evaluate the nematicidal activity of cinnamon bark extracts (CE) and chitosan (Cs) against Meloidogyne incognita and Pratylenchus coffeae under pot and field conditions. In the pot experiments, CE mixed with Cs effectively inhibited M. incognita and P. coffeae infection on robusta coffee plants. The formulations applied, CE:Cs = 8 mg:30 mg, CE:Cs = 16 mg:60 mg and CE:Cs = 16 mg:60 mg per pot, significantly reduced the gall index and nematode number in 5 g of root and 100 g of soil. In addition, the application of CE:Cs = 48 mg:180 mg CE:Cs = 80 mg:300 mg and CE:Cs = 112 mg:420 mg plant−1 effectively reduced root gall formation and nematode density in roots and soil compared with the non-treated control under field conditions. Nematode density in the roots was positively correlated with the rate of yellow leaf disease. These results suggest that cinnamon mixed with chitosan may be used as an effective eco-friendly pesticide against plant-parasitic nematodes.

Annual ring formation is considered a source of information to investigate the effects of environmental changes causedby temperature, air pollution, and acid rain on tree growth. A comparative investigation of annual ring growth of Cryptomeriajaponica in relation to environmental changes was conducted at two sites in southern Korea (Haenam and Jangseong).Three wood disks from each site were collected from stems at breast height and annual ring growth was analyzed.Annual ring area at two sites increased over time (p > 0.05). Tree ring growth rate in Jangseong was higher than that inHaenam. Annual ring area increment in Jangseong was more strongly correlated with environmental variables than thatin Haenam; annual ring growth increased with increasing temperature (p < 0.01) and a positive effect of NO2 concentrationon annual ring area (p < 0.05) could be attributed to nitrogen deposition in Jangseong. The correlation of annualring growth increased with decreasing SO2 and CO2 concentrations (p < 0.01) in Jangseong. Variation in annual growthrings in Jangseong could be associated with temperature changes and N deposition. In Haenam, annual ring growth wascorrelated with SO2 concentration (p < 0.01), and there was a negative relationship between precipitation pH and annualring area (p < 0.01) which may reflect changes in nutrient cycles due to the acid rain. Therefore, the combined effects ofincreased CO2, N deposition, and temperature on tree ring growth in Jangseong may be linked to soil acidification in thisforest ecosystem. The interactions between air pollution (SO2) and precipitation pH in Haenam may affect tree growthand may change nutrient cycles in this site. These results suggested that annual tree ring growth in Jangseong was morecorrelated with environmental variables than that in Haenam. However, the further growth of C. japonica forest at twosites is at risk from the long-term effects of acid deposition from fossil fuel combustion