Lodging caused by typhoon or windstorm is one of the biggest problems in silage corn production in Japan. During a field experiment in which we compared 13 commercial silage corn cultivars, serious lodging occurred as a result of a strong windstorm that occurred during the mid-growth period (49 days after seeding). We examined the relationship between the lodging tendency and morphological characteristics of those cultivars. Lodging occurred in 66% of the experimental field area, while there was a varietal difference in the area where lodging occurred. As the growth stage was advanced, the area affected by lodging increased in size. However, lodging resistance evaluated by the method of Koinuma et al. (1998) was not significantly different among the 13 cultivars, when it was measured at the milk-ripe stage of each cultivar examined. Recovery from lodging was easy when the plant height or gravity center of the shoot was low. We concluded that recovery from lodging would be possible before harvest when it occurred within 20 days prior to the silking stage.

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The conventional method of introducing Zoysia japonica Steud. seedlings into the field requires intensive labor ; it comprises digging up a hole with a hoe and then transplanting the seedlings. However, we modified the transplant method such that no tools were required because the seedlings were transplanted on dung pats. In this study, we evaluated the increase in work efficiency and labor stress reduction observed as a result of transplanting the seedlings on dung pats. Further, the working efficiency and planters' work postures when using this method were compared with those observed in the case of the conventional transplanting method. Work efficiency (number of established seedlings that could be transplanted in approximately one minute) while transplanting seedlings on dung pats was significantly higher than that observed during the conventional method. Further, the planters' work posture was evaluated by OWAS. In the case of the conventional method, the postures of 12.1% of the planters were categorized under the category that required immediate improvement. On the other hand, in the other method, only 2.2% were classified under the abovementioned category. Based on the above results, it was concluded that transplanting seedlings on dung pats was efficient and not laborconsuming.

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Unwilted and slightly wilted grass silage added with formic acid, a bacterial inoculant, and a mixture of bacterial inoculant and enzyme were fed to sheep, and the nutritive value and nutrient intake were investigated. The fermentation quality of unwilted silage was higher in the formic acid-added and bacterial inoculant+enzyme-added silage than in the untreated silage. In slightly wilted silage, the fermentation quality was improved in all additive groups. Regarding the nutritive value of silage, the DCP, TDN, and DE contents in the formic acid-added unwilted silage and the TDN content in the formic acid-added slightly wilted silage were significantly higher than those in the untreated silage. As for the nutrient intake, the DCP, TDN and DE intakes in the formic acid-added unwilted silage were significantly higher than in the untreated silage. Based on the above findings, a higher fermentation quality, nutritive value, and nutrient intake than those in the untreated silage were obtained only in the formic acid-added unwilted silage.

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The objective of this study was to classify Japanese alfalfa varieties using fall dormancy ratings(FDR). In 2004 and 2005 fall dormancy tests were carried out at three research fields of National agricultural research center for Hokkaido region, located in Sapporo, Memuro and Monbetsu. Nine Japanese cultivars, eleven breeding strains and thirteen foreign cultivars including nine check cultivars were used in this study. The FDR of Japanese alfalfa cultivars for the warmer regions ranged from 5.9 to 7.0. On the other hand, FDR of those for the cold regions ranged from 2.2 to 5.3. The range of FDR was greater in cold region cultivars than those of warmer region cultivars. The FDR of Haruwakaba was smallest in cultivars for the cold regions, which suggested that adaptability to the cold regions was the greatest in Haruwakaba. We discussed advantages of the FDR method over previous mehods in classification of Japanese alfalfa cultivars.

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In vegetation survey and analysis methods using the power law, which was developed by the Ecological Laboratory, Faculty of Science, Ibaraki University, Japan, statistical tests cannot be used to compare occurrence frequencies (p) and spatial heterogeneity values (δ), which indicate differences from the random distribution of each species in a community. We introduced a two-way layout (randomized block design) with replications (blocks) to allow statistical tests on the means of these parameters. We also introduced a new parameter (ε) to represent the difference in the mean spatial heterogeneity of each species from that of the surveyed plant community. The design was tested using a survey of a grazed, semi-natural grassland in central Japan. The plant species were divided into four groups based on life form ; erect-type with a large crown, erect-type with a small crown, creeping type, and bunch type. These groups differed in each of the two types of spatial heterogeneity. Differences in the δ- and ε-values among species within each group were also detected and were explained based on a more precise life form analysis using analysis of variance.

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We examined for a use of phenylalanine fermentation byproduct (PFB), monosodium glutamate fermentation by-product (MSG), lysine fermentation byproduct (LFB) and inosine fermentation byproduct (IFB) as silage additive (3%v/w) for ensiling Italian ryegrass (Lolium multiflorum Lam.). Effects of desalting were also evaluated on the PFB additive. Except for the IFB additive, the three amino acid fermentation byproducts significantly improved the silage quality with promoted lactic acid fermentation and lowered acetic and butyric acids production and dry matter (DM) loss. They also significantly increased crude and true protein contents and lowered neutral detergent fiber (NDF) content in the silage. The MSG additive significantly increased in situ DM and NDF degradability in the rumen, while the undesalted PFB additive increased in situ NDF degradability. The improvement of lactic acid production in the silage was significantly related with magnesium concentration, and that of the in situ rumen degradability was significantly related with total concentration of anions, which varied among the four amino acid fermentation byproducts.

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Japanese feed corn production must be more efficient and less reliant on herbicidal weed control to both reduce environmental concerns and remain economically viable. As an alternative to herbicide, we tested the effects on crop yield of differing tillage systems (normal and intensive) for control of C. japonica in annual corn fields in Japan. Normal fall tillage, with or without intertillage, significantly reduced fresh weight C. japonica at harvest and maintained corn yield. Intensive fall tillage further reduced fresh weight C. japonica at harvest while maintaining corn yield. Fall tillage decreased C. japonica density, above-ground biomass, individual top weight, and individual rhizome weight at the end of the weed control period. Our data indicate that conventional procedures plus normal fall tillage in C. japonica infested fields maintained corn yield equivalent to weed free fields but did not reduce infestation. To control C. japonica more effectively, we recommend conventional procedures plus intensive fall tillage to minimize C. japonica density while maintaining corn yield. Suggested tillage systems do not require additional herbicide or machinery investment to control C. japonica.

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We measured the species composition, species diversity, ecological dominance, and changes in soil physicochemical properties during vegetation regeneration in the Horqin Sandland of northeast China. Dune types changed during the regeneration process and were classified into the following four stages (in order of succession): mobile, semi-mobile, semi-fixed, and fixed dunes. Our results indicated that a typical community type occurred at each stage of vegetation regeneration and there were obvious effects of the dominant species in each community type. During vegetation regeneration, ecological functions and vegetation indices improved, as indicated by the species richness, Shannon-Wiever diversity, species evenness, ecological dominance, and plant morphology and composition (to family) of the vegetation. During community succession, annual plants in the mobile dunes were gradually replaced by perennial plants. However, Chenopodiaceae species were found at all stages of regeneration, and especially at the initial stage of succession. Gramineae and Legumi-nosae species increased with succession, indicating the increased colonization of steppe plants and the improvement of pasture quality. The soil organic matter content also increased with vegetation regeneration, but the bulk density of the soil did not change. The aboveground standing crop reached a maximum on the fixed dune, followed by the semi-fixed, semi-mobile, and mobile dunes.

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