Spatial and temporal dynamics of habitat availability and stability for a critically endangered arboreal marsupial: implications for conservation planning in a fire-prone landscape

Landscape Ecology - Effective conservation planning for species depends on vegetation models that can capture the dynamics of habitat elements across both spatial and temporal domains....     

Landscape structure as a mediator of ecosystem service interactions

Landscape Ecology - Management of multiple ecosystem services (ES) is complex, in part due to synergies and trade-offs among ES. Landscape configuration—the spatial arrangement of patches in...     

Criteria for determining purity of Fusarium mycotoxins

Physical and chemical properties that may be used to determine the purity of several Fusarium mycotoxins have been investigated. A combination of analytical procedures, which include high performance thin-layer chromatography (HPTLC), liquid chromatography (LC), gas chromatography (GC), gas chromatography/mass spectrometry (GC/MS), ultraviolet spectrometry (UV), and nuclear magnetic resonance (NMR) spectrometry have been used to examine mycotoxin standards obtained from commercial sources and from laboratory fermentations. Results of this investigation indicate that commercially available standards are greater than 90% pure, but the label weight of purchased reference standards in individual containers should be verified. Mycotoxin standards, determined to be greater than 98% pure by HPTLC, LC, and GC/MS, were examined by UV spectrometry and the coefficients of extinction were determined. An interlaboratory study, involving 5 collaborators who determined coefficients of extinction (in methanol) for identical samples, gave the following results: alpha-zearalenol (lambda 236 = 28 538 +/- 558); beta-zearalenol (lambda 238 = 24 963 +/- 747); deoxynivalenol (lambda 219 = 6395 +/- 349, lot 1), (6020 +/- 228, lot 2); and T-2 toxin (lambda 202 = 3681 +/- 255). UV maxima and coefficients of extinction are also reported for HT-2 toxin (lambda 202 = 1959), diacetoxyscirpenol (lambda 203 = 2487), neosolaniol (lambda 203 = 2644), nivalenol (lambda 220 = 5142), and fusarenon-X (lambda 217 = 5997).     

Molecurar Breeding for Resistant Varieties Against Asian Rice Gall Midge in China

Asian rice gall midge （GM） is a major rice pest in South China. Breeding resistance varieties has been a viable and ecologically acceptable approach for managing the pest. This paper reports that the progress of breeding resistant varieties using the markers linked to Gin6 against GM fxom the year 1998 to 2006 in China. The DNA fingerprints of 4 biotypes of GM population fxom 7 locations were analyses by AFLP. Base on the fine mapping of resistance gene Gin6 against all 4 Chinese GM biotypes by RAPD and SSR methods respectively, the STS markers and SSR markers linked to gene Gin6 were used for breeding through MAS. Some new resistant garplasm with Gin6 gene were created. And six cultivars and six two-line or one line three-line hybrid rice against GM were bred and extended to the farmer. The technique system of MAS for resistant varieties against Asian rice gall midge was set up at Guangdong province of China.     

Drought Resistant Rice： an Integrated Crop Improvement Strategy

Rice physiological sensitivity to drought and its impact on crop productivity in water-limited environments are well-documented （O＇Toole, 2004）. However, rice yields in drought-prone rainfed lowlands and most upland areas remain low and the current challenges are to reduce yield gaps observed between experimental plots and farmers＇ fields, and to increase rice water productivity to economic levels （Bennett, 2003; Pandey et al., 2007）. The unpredictability of drought and its inherent complexity have made it difficult to characterize component traits required for improved performance, hindering the breeding efforts to enhance drought resistance.