Identification of<Emphasis Type="Italic">Pseudomonas viridiflava</Emphasis> on tomato by traditional methods and enzyme-linked immunosorbent assay

Pseudomonas viridiflava is one of the causal agents of tomato stem necrosis in the eastern Mediterranean region of Turkey. The bacterium causes general wilting, yellowing of tomato plants, dark blotches on the pruning sites of the stem, browning, and hollowing of the pith.P. viridiflava strains, isolated from Antakya and Mersin, were identified by traditional methods and indirect enzyme-linked immunosorbent assay (ELISA). For indirect-ELISA, polyclonal antisera were produced against a regional isolate ofP. viridiflava (AD-OZ 3a). Using indirect-ELISA, the pathogenic bacterium was identified rapidly and safely from both pure culture and inoculated plants in 2 days. There was no cross reaction with other stem necrosis pathogens. With indirect-ELISA, the lower limit forP. viridiflava detection in pure culture was 10³ colony-forming units per milliliter. http://www.phytoparasitica.org posting Feb. 11, 2004.     

Quantification of the impacts of climate warming and crop management on canola phenology in Punjab,Pakistan

Yield is influenced by the length of the growing season, which is affected by weather conditions and management practices of a crop, including sowing dates and shifting of cultivars. It is necessary to understand the effects of agronomic management practices and weather variables on phenological stages and crop phases in order to develop strategies for adaptation of agricultural systems to changes in climatic conditions. The goal of this study was to determine the impact of warming trends on phenology of canola from 1980 to 2014 for central and southern Punjab, Pakistan. Sowing, emergence, anthesis and physiological maturity dates were delayed by an average of 6.02, 3.14, 3.31 and 1.89 days per decade, respectively. The duration of sowing to anthesis, sowing to physiological maturity and anthesis to physiological maturity phases decreased an average 2.71, 4.13 and 1.42 days per decade, respectively, for all 10 locations that were analysed in this study. The sowing, emergence, anthesis and physiological maturity dates were positively correlated with an increase in temperature by an average 2.71, 1.41, 1.49 and 0.85 days per °C, respectively. However, the phenological phases such as sowing to anthesis, anthesis to maturity and sowing to maturity were negatively correlated with an increase in temperature by an average of 1.22, 0.64 and 1.86 days per °C, respectively, for all 10 locations. Applying a process‐based CSM‐CROPGRO‐Canola model using a standard cultivar (field tested) for all locations and years indicated that the simulated phenological stages occurred earlier due to the warming trend compared to the observed phenological stages. One‐quarter of the negative effects of this thermal trend was compensated by growing new cultivars that had higher thermal time requirements. Therefore, new canola genotypes with a higher number of growing degree day requirement and high temperature tolerance should be a priority for evolving new cultivars.     

FTIR spectroscopy can be used as a screening tool for organic matter quality in regenerating cutover peatlands

Vegetational changes during the restoration of cutover peatlands leave a legacy in terms of the organic matter quality of the newly formed peat. Current efforts to restore peatlands at a large scale therefore require low cost and high throughput techniques to monitor the evolution of organic matter. In this study, we assessed the merits of using Fourier transform infrared (FTIR) spectra to predict the organic matter composition in peat samples at various stages of peatland regeneration from five European countries. Using predictive partial least squares (PLS) analyses, we were able to reconstruct peat C:N ratio and carbohydrate signatures with reasonable accuracy, but not the micromorphological composition of vegetation remains. Despite utilising different size fractions, both carbohydrate (<200 μm fraction) and FTIR (bulk soil) analyses report on the composition of plant cell wall constituents in the peat and therefore essentially reveal the composition of the parent vegetational material. The accuracy of the FTIR-based PLS models for C:N ratios and carbohydrate signatures was adequate to allow for their use as initial screening tools in the evaluation of the present and future organic matter composition of peat during monitoring of restoration efforts.