Two on-farm experiments (experiments 1 and 2) were conducted to evaluate the suitability of ridge-making seeding and controlled-release fertilizer in alleviating excessive soil moisture stress on silage corn. Two corn cultivars, Cecilia and 31N27 were examined in the study because they were evaluated as flooding-tolerant and flooding-susceptible, respectively, in a previous report. In Experiment 1, a 2-week period of artificial waterlogging treatment using irrigation water was implemented starting 10 weeks after planting. The number of days when a dairy average of underground water table exceeded 200 mm below ground surface was 26 days and 39 days among the growth period of 132 days in Experiment 1 and that of 133 days in Experiment 2, respectively. In both experiments, the application of ridge-making seeding and controlled-release fertilizer increased the dry matter yield of the two cultivars, although the effects in Experiment 2 were not statistically significant because of large variance in dry matter yields among the replications. Comparing the dry matter yields of the two cultivars shows that the results of Experiment 2 were consistent with the flooding tolerances of both types, while those of Experiment 1 showed an opposite pattern.

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We examined the effects of the following factors on herbage intake : grass length at the start of the grazing season (20 cm, 30 cm and 40 cm, experiment 1), appropriate trimming dates (middle of June, end of June and beginning of July, experiment 2) and no trimming when grass length at the start of the grazing season was 20 cm (trimming and without trimming, experiment 3). In experiment 1, although mean grass length throughout the grazing season tended to lower in the pasture with grass length of 20 cm at the start of the grazing season, herbage intake was similar in the pasture with different grass lengths. In experiment 2, trimming to 10 cm at the beginning of July resulted in elimination of heading stems and supply of sufficient herbage mass. In experiment 3, herbage intake in the pasture with grass length of 20 cm at the start of the grazing season without trimming was similar to that in the pasture with trimming. Based on the results, we recommend grass length of 20 cm at the start of the grazing season without trimming and, if needed, trimming to 10 cm at the beginning of July.

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The purpose of this study was to develop a database that allows broad information exchange of cultivation history information and a method for label printing, in order to promote distribution of round bales of whole crop rice and whole crop wheat which were widely used as commercial feed. The database was used to record field information, cultivation information, and field conditions at the time of harvest. The database system can be operated using a personal computer and a handy terminal (HT). During harvest, the HT was used to read the QR-code of an information input sheet to record field conditions in the database. A label containing the cultivation history data and the QR-code was printed using a mobile printer and stuck on a round bale. With respect to the harvest of whole crop wheat, the time required for the operation of this system represented 5% of all the harvest work. The collection of cultivation history information and label management did not constitute an additional burden during harvest work. Information printed on the label exposed to outdoor condition could be read for one year.

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Characteristics of nitrate-N and nutrients accumulation of sorgo type sorghum varieties including 'SIL-05', a new genotype developed for high sugar accumulation, was evaluated. The varieties of 'SIL-05', 'FS501', 'SG-1A' and 'Sugar Graze' were cultivated in fields of NARO Institute of Livestock and Grassland Science located in Nasushiobara under a heavy N application rate of 55 kgN/10 a in 2009 and 2010. Nitrate-N concentrations of 'SIL-05' on dry matter (DM) basis were turned out to be lower by about 60-70% than those of the other three varieties in nitrate-N accumulation and those of 'SIL-05' were below 0.2% which is a guideline level for avoiding nitrate poisoning for ruminants in Japan. Further, N, K, Ca and Mg concentrations of 'SIL-05' were also lower by about 30-40% than the other varieties. The lower nutrients concentration comes from lower concentrations in stem. As for DM production, no significant differences were observed between the 4 varieties tested. During the maturing period, 'SIL-05' was inclined to show higher DM production and nitrogen assimilation rates than 'FS501' and this might be involved with lower nitrate concentration of 'SIL-05'. In conclusion, 'SW-05' is a useful variety to decrease nitrate-N concentrations under higher N fertility conditions.

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The carbon and nitrogen (C-N) mass of each plant was measured in abandoned, harvested, burned, and burned-harvested plots in a Miscanthus sinensis Anderss.-dominated grassland for three years. In the abandoned plot, the C-N mass of M. sinensis plants decreased and that of woody plants increased each year, whereas the opposite occurred in the harvested plot. The C-N mass of M. sinensis plants increased rapidly after burning. The C-N ratio of M. sinensis plants was higher (mean=64) than that of other herbs and woody plants (means=35, 36, respectively). The C-N ratio of M. sinensis plants and other herbs was heigher in the burned and burned-harvested plots. The dominance of M. sinensis plants with a higher C-N ratio leads to an increase of the C-N ratio and lower nitrogen availability in the grassland plant community. Low nutrition conditions after burning may promote the dominance of M. sinensis over other plants.

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This study was conducted to examine feed characteristics of rice plant (Oryza sativa) as whole crop silage (whole crop rice silage ; WCRS) after receiving insect damage by Straight swifts (Parnara guttata). The rice plant variety was Hoshiaoba, harvested at full-ripe stage and prepared in round baled silage with urea liquid. The ingredient digestibility and nutritive value were evaluated in four Holstein steers (average weight : 449.6±9.2 kg). Dry matter weight in 10 a of insect-damaged rice plant at the yellow-ripe stage was less than approximately 30% that of a normal rice plant of same variety (Fukagawa et al. 2004). All chemical compositions except crude protein of insect-damaged WCRS were less than those of normal WCRS in the Standard Table of Feed Composition in Japan (2009). Additionally, all ingredient digestibility of insect-damaged WCRS showed a similar tendency. Results show that total digestible nutrients and metabolizable energy of insect-damaged WCRS were, respectively, 36.5% and 5.70 MJ/kg DM, exhibiting a very low value. Results suggest that insect damage during rice plant cultivation not only decreases yield ; it also decreases all chemical compositions except crude protein, all ingredient digestibility, and all nutritive values of WCRS.

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