Wheat yellow mosaic virus (WYMV) was identified in 25 of 27 wheat (Triticum aestivum) samples from six provinces in China using reverse-transcription polymerase chain reaction. Wheat spindle streak mosaic virus was not detected. Thus, contrary to previous reports, WYMV was the only bymovirus detected in wheat in China. The cDNA fragments corresponding to coat protein coding regions of five WYMV isolates from China were cloned and sequenced. Deduced amino acid comparison of coat proteins among these five isolates, another Chinese WYMV isolate HC, and one isolate from Japan showed very high sequence conservation, particularly in both the N- and C- termini. However, a highly virulent isolate HC from Henan Province showed four amino acid substitutions in highly conserved amino acid positions which might play a role in its pathogenic variation.

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Animal slurry is separated in order to avoid excessive nitrogen, phosphorus and potassium (NPK) fertilization of crops in the field. To enhance fertilizer efficiency further, slurry and its separation products may be acidified, for instance in animal houses. The current study quantified the effects of these treatments, both individually and in combination, on fertilizer efficiency, energy production and heavy metal accumulation as a result of manure management. Acidification increased the availability of N to plants in the manure applied, and provided a better match between plant-available NPK in the manure and separation fraction applied to fields and crop need. Total biogas production was not affected by separation, whereas acidification reduced biogas production because the process was inhibited by a low pH and a high sulphur concentration. The amount of copper applied per hectare in the liquid manure to the wheat field was lower than the amount taken up and more zink and copper was applied in the solid fraction to maize field than taken up. The transportation and field application of solids and liquids did not increase management costs when compared to the transportation of slurry alone, but the investment and running costs of separators and manure acidification increased overall management costs.

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