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Some small fragments of rag paper - made more than a thousand and a few hundred years ago, and excavated at Turfan, west of China by the Otani-expedition dispatched there during the late Meiji and the Taisho eras - were measured by PIXE. Bromine was highly Detected in all these ancient fragments and modern paper samples that had been placed together with these Turfan manuscripts. In other paper samples, bromine could not be detected (H⁺, 4MeV, 50μC and H⁺, 2MeV, 100μC) and their average concentration was about 1.1ppm (S.D.=1.11ppm, N=15, 0.3~3.4ppm). The bromine contamination of ancient sutras is mainly caused by larvicide of methyl bromide, and the observation suggests that the ancient manuscripts might be spoiled gradually by agricultural chemicals for protecting them from vermin.

Thirty soil samples, from 6 different farms with vine decline symptoms, plus two peat samples from a nursery were collapsed plants were previously sown, were analyzed for presence of organisms associated with the disease. With a soil-dilution plating method, only Macrophomina phaseolina and Acremonium were detected, in 2 samples each fungus. With a melon bait plant technique, named "soil phytopathometry", Olpidium bornovanus often together with Melon necrotic spot virus, was found in 70% of all the samples, corresponding with all the farms studied and the peat. Other pathogens that were detected less frequently included Monosporascus cannonballus (3.3%) and Rhizoctonia solani (3.3%). No Plectosporium tabacinum neither Rhizopycnis vagum (other two fungi associated with vine decline) were detected. Fusarium solani, that was detected very frequently (87%), was not associated with disease occurrence after a pathogenicity test. Consequently, O. bornovanus and MNSV were uniquely associated with disease occurrence and thus are the most probable cause of melon vine decline in the fields studied.