Herbage production and utilization in a bahiagrass (Paspalum notatum Flugge) pasture rotationally grazed by breeding Japanese Black cows were quantified in a cow-calf system in coastal Miyazaki, southwestern Japan. Herbage mass (range = 20-421g DM/m^2) increased during the pre-grazing season (mid-April to late May), and thereafter repeated a decrease during a grazing period and an increase during a rest period in the grazing season (late May to late October). Dry matter digestibility and nitrogen concentration of herbage (range = 471-593 and 13-26g/kg DM, respectively) decreased from May to October. The rate of herbage production (range = 2.4-8.8g DM/m^2/day) tended to peak in early July, with the potential rate (range = 3.0-13.7g DM/m^2/day) being high until early July and decreasing thereafter. The rate of herbage consumption and dry matter intake by cows ranged from 19.9-59.2g DM/m^2, day and 14.8-12.9g DM/ kg LW/day, respectively. Total herbage production and consumption from mid-April to late October (≈growing season) were respectively 1025-1033 (mean = 1029) g DM/m^2 and 892-941 (mean = 916) g DM, m^2, with degrees of utilization of 0.86-0.92 (mean = 0.89). The study shows that a bahiagrass pasture, which is intermediately productive among sown pastures in Japan, is highly utilized by breeding Japanese Black cows, providing sufficient digestible energy and protein.

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A pot experiment was conducted to investigate the effect of phosphorus (P) nutrition on phytic acid accumulation in grains measured by plant growth and P, Ca and Mg and phytic acid concentrations in maize (Zea mays L.) grown with increasing amounts of P fertilizer. Phosphorus was applied as fertilizer at three levels : 10^<-2> (1P treatment), 2×10 ^2 (2P treatment) and 4×10^<-2> (4P treatment) kg m^<-2> of P_2O_3 as superphosphate. Total plant dry weight, grain yield, total P concentration in the plant and grain, and phytic acid concentration in the grain were increased with increasing P levels. Positive relationships between the concentrations of total P and phytic acid concentration in the grain were observed. The percentage of phytic acid P concentration to total P concentration in the 1P treatment was 38%, and that in the 4P treatment was 58%. The P absorbed was mainly distributed in the grain. The amount of P translocated to the grains was higher in the 4P treatment than in the 1P treatment. These results suggested that grain yield and phytic acid synthesis in grains are regulated by altering the P status of plants.

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Growth of napiergrass (Pennisetum purpureum Schumach) and kinggrass, the hybrid between napiergrass and pearl millet (Pennisetum typhoides), was measured under three levels of chemical fertilizer supply during the growing season. Plants were grown in 1/2000 a wagner pot by transplanting single tillers and growing them under natural conditions in 1999 and 2000. Plant length, total expanded leaf number per shoot (TELN/S), total dry matter weight (TDMW), stem dry matter weight, root dry matter weight and mean tiller dry matter weight (MTW) increased with time for both grasses and increased with an increase in the level of fertilization. Top per root ratio in both grasses increased but the ratio of leaf blade per stem with leaf sheath did not vary with an increase in the level of fertilization. Crop growth rate (CGR) and leaf area index (LAI) increased for both grasses as the level of fertilization increased. The relationship between TELN/S and LAI was quadratically negative for each level of fertilization in both napiergrass and kinggrass, and the change in TELN/S with time was one of the major factors contributing to the change in LAI. The increase in LAI was linearly related to that in CGR, which was affected by the increase in level of fertilization. With an increase in level of fertilization, tiller number (TN) and TELN/S increased, which resulted in an increase in TDMW because of the change in LAI. It was suggested that these were plant factors that increased TDMW of both grasses both years under higher input of fertilizer. The difference in dry matter productivity between napiergrass and kinggrass was negligible because the increases in TN, TELN/S and MTW compensated for each other in both species as affected by the increase in fertilization.

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To understand the effects of Neotyphodium endophytes on plant characteristics, it is necessary to provide clones with and without endophyte. One method is to remove the endophyte from infected clones by fungicides. To establish an effective method perennial ryegrass (Lolium pcrcrific L.) plants infected with the endophyte N, tolii and tall fescue (Festuca arundinacea Schreb.) plants infected with N, coenophialum were used to test 3 different fungicides at 3 levels of concentration, and 3 soaking times. The fungicide benomyl was effective in killing endophyte in both perennial ryegrass and tall fescue, triforine was effective in tall fescue and effective in some perennial ryegrass plants. Thiophanate-methyl had little effect on endophyte in perennial ryegrass and had no effect on endophyte in tall fescue. These results indicate that interactions exist between these fungicides and Neotyphodium spp. The endophyte was killed in all 9 treated ramets of both perennial ryegrass and tall fescue when they were soaked in 2% benomyl solution for 18 hours. Furthermore, the endophyte was killed in all the tall fescue ramets soaked in 2% of triforine for 18 hours. The killing of endophyte w-as enhanced with both the increase in fungicide concentration and length of time in the fungicide.

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In northeastern China, the degradation of semi-arid grasslands caused by overgrazing is a serious concern. We surveyed three grasslands with different degrees of grazing intensity (heavily, intermediately and lightly grazed grasslands) in the Heilongjiang Province. In each grassland, plant species diversity and its spatial heterogeneity were estimated by the frequency of occurrence of each plant species. Cleistogenes squarrosa, Chenopodium cenlrorubrum and a Carex species were commonly found in all three grasslands. Euphorbia humifusa var. pilosa and two Artemisia spp-occurred frequently in degraded grasslands, and are considered to be indicators of low-quality grasslands. The plant community in the lightly grazed grassland was composed of a few dominant species, several species that occurred occasionally and many rare species. On the other hand, that in the heavily grazed grassland was composed of a few highly dominant species and many rare species. We found 39, 53 and, 52 plant species within each plot (0.5×50m) in heavily, intermediately and lightly grazed grasslands, respectively. With increasing grazing pressure on the grasslands, species diversity decreased and the spatial heterogeneity of species diversity increased.

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In this study, we developed a portable automatic measuring system for recording the number of tail swishing against pest flies in grazing cattle. Four Japanese Black cattle were monitored as focal animals from August to October, and the number of their tail swishing was recorded for 21 hours with the developed measuring system each month. Simultaneously, an individual observer followed each focal animal for 6 hours from 9 : 00 to 15 : 00 in the pasture and the number of tail swashing was recorded continuously. Then, we compared the numbers of tail swishing by the measuring system and direct observation focal animal sampling. The measuring system could record the number of tail swishing continuously for 21 hours. The number of tail swishing recorded by the measuring systems was higher than by direct observation, and the mean difference in tail swishing was 8.6%. The present study suggested that the developed system was a useful device for recording the number of tail swishing in the grazing cattle, although a corrective factor may need to be applied to the results.

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Relationship between Distance from Spot of Urine Perfusion and Salt Tolerance in Reed Canarygrass (Phalaris arundinacea L.)

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