In most cases of Japanese grass cultivars, certified seed is increased in the western coast of USA, and population shifts are sometimes at issue. To investigate the population stability, characteristics of Breeder Seed (BS), Foundation Seed (FS) and Certified Seed (CS) of three and two Italian ryegrass cultivars were evaluated in 1985 at Saku and at Nishinasuno, respectively. Differences of characteristics between two locations were larger in 'Nasuhikari' in almost of all characters than in 'Minamiwase' (Table 3). The number of characters, in which significant differences were found among generations, was less in 'Minamiwase' than in 'Nasuhikari' or in 'Yamaaoba'. It was assumed that population was more stable in cultivars with less variability than in cultivars with greater variability. Among characters, the difierences were observed more frequent in date of heading. No consistent change in the date of heading was observed in 'Minamiwase' with advancing generation, but 'Nasuhikari' and 'Yamaaoba' markedly shifted toward earliness (Fig. 1). In some characters concerned with grass height, tendency toward higher with advancing generations was observed in most experiments with the exception of 'Minamiwase' at Saku (Fig. 2). Two BS lots differed in harvesting year were also compared using 'Nasuhikari' (Table 4). Significant differences were observed in several characteristics including the date of heading at both locations. Difference of characteristics at two locations, characteristics change between BS and FS, and differences between two BS lots suggest need to pay attention to population stability even if the seed would be multiplied in our country.

View full abstract

To investigate population stability with advancing generation, characteristics of Breeder Seed (BS), Foundation Seed (FS) and Certified Seed (CS) of two orchardgrass cultivars were evaluated at Saku and at Nishinasuno in 1985-86 and in 1985, respectively. Number of characters in which significant differences were found among generation, was less in 'Okamidori' than in 'Aonami' (Table 3). It was assumed that population was more stable in a cultivar with less variability in heading date than in a cultivar with greater variability. The heading date tended to shift toward earliness with advancing multiplication genarartions in both cultivars (Fig. 1). The difference between BS and CS was smaller at Nishinasuno than at Saku, and in the year after the next of planting than in the next. Length to top of head exhibits a tendency toward higher with advancing generation (Fig. 2). Characteristics of two BS lots differed in harvesting year were compared using 'Okamidori'. Large population shift was not occured except for the length of flag leaf (Table 4). Significant differences among generations were hardly observed in common with locations and years. This indicates that data with more than one year or one location are required to evaluate population stability of orchardgrass cultivars, especially in the area where orchardgrass is seeded in fall. Furthermore, there is a possibility that putting too much importance on statistical analysis induces wrong results.

View full abstract

The proportions of buds, which were dormant or aborted and died or produced branches (current year's stems for two year old buds), were estimated in the 1st and 2nd years of bud growth to obtain basic information on the branching structure and foliage production of kudzu-vine. In the 1st year, the budbreak of the middle bud tended to precede that in the right and left buds. Averaged across the main stem and branches, the proportion of node type B, in which the middle bud aborts and dies and the lateral buds remain dormant, was a maximum of more than 85%, followed by type A in which all three buds are dormant and type C in which the middle bud produces a branch and the lateral buds are dormant, with about 6% each. The lower stem portion had more A type nodes than the upper and middle portions, while C type nodes occurred in desending order on the upper, middle and lower stem portions. The middle stem portion had slightly more B type nodes than the two other portions. Sixty seven to 84% of buds remained dormant in the 1st year, varying with the main stem, branches, or stem portions. The tendency for the middle bud to precede the laterals in budbreak was maintained in the 2nd year, though it became slightly less common compared to the 1st year. A greater proportion of the dormant buds in A type nodes remained dormant in the 2nd year compared to B and C type nodes. The proportion of dormant buds was higher in lower stem portions in the 2nd year, while the reverse was true for sprouted buds. It is thought that these results are a reflection of differences between the stem portions in the balance of plant hormones involved in bud dormancy and in deterioration of vascular bundles which connect the stems with the buds. Also, they must be related to the development of the branching structure and foliage production system characteristic of kudzu-vine.

View full abstract

The effect of different levels of N nutrition (N and 3 N treatment) on some chemical composition was determined in regrowing leaf blade of orchardgrass after cutting. The regrowth tissues were predominated by cut-leaves in both treatments by 7th day after cutting, but after 10th day they were consisted of cut- and uncut-leaves. The plant in 3 N treatment was faster on the speed of regrowth and leaf opening and greater on proportion of uncut-leaf blade than that in N treatment. The chlorophyll concentrations in cut-leaves of N treatment and uncut-leaves of 3 N treatment showed the maximum value on 10th day after cutting and had little variation after that, but those in only cut-leaves of 3 N treatment increased furthermore. The accumulation rate of chlorophyll in uncut-leaves of N treatment was remarkably slow as compared with others. The concentrations of TCA insoluble nitrogen were higher in the leaves of 3 N treatment than in those of N treatment since that time of cutting. After small decrease, they increased in both treatments with the increase of chlorophyll concentration from 5th day after cutting and attained to the maximum on 10 to 14th day in both cut- and uncut-leaves. Consequently, the curve of Chl./TCA insoluble nitrogen in leaves showed a clear shoulder on 10th to 14th day except uncutleaves of N treatment which took a low nitrogen concentration. The accumulation of chlorophyll which was shown in cut-leaves of 3 N treatment after 10th day was not accompanied by the increase of TCA insoluble nitrogen. The concentrations of TCA insoluble phosphate and 85% ethanol soluble carbohydrates in cut- and uncut-leaves were higher in 3 N than N treatment and attained to the maximum on about 10th day in each treatment. As mentioned above, the difference in greening pattern of the leaves was observed between the regrowing plants with different N levels. And it was suggested that the reserved nitrogen in stubble at the early stage and absorving nitrogen at the later stage of regrowth period were important as nitrogen sources of leaf protein.

View full abstract

Six grass species and three legume species, all common in pastures and meadows, were grown in sand culture in "donor pots". Leachate from each donor pot including the root-exudates, was applied to "receiver pots" of the same nine species in sand culture, separately and the shoot dry weight of the plants in the receiver pots was measured to assess the response to leachate. The results obtained are summarized as follows: 1. Everyone of the donor species caused a reduction in the mean receiver weight compared with the plant-free control ; Lolium perenne causing the greatest inhibition and Medicago sativa the least. 2. Most of the receiver species, particulally in Medicago sativa and Trifolium repens were inhibited more by the leachates of grass species pots than those from legume species pots. 3. Three species, Trifolium hybridum, Trifolium repens and Lolium perenne, were inhibited more by the leachate of their own species than those of other species (auto-inhibited). All other species showed the opposite response (allo-inhibited). 4. In general, it was found that species exhibiting the higher sensitivity to the allo plant donor treatments tended to exhibit the higher sensitivity to the auto donor treatment. 5. These results were discussed in relation to the behaviour of each species in the field.

View full abstract

Field investigation on plant and soil potassium was carried out in grazing pasture and in meadow of mineral soil. The results obtained were as follows ; 1. Plant potassium content in the grazing pasture was higher than in the meadow of all the species of the forage plants (Italian ryegrass, orchardgrass, tall fescue, alfalfa, red clover and white clover) and of a weed (Wild common vetch). Among the forage plants, white clover and tall fescue showed the highest and the lowest potassium content, respectively. 2. Monthly change of potassium content in the forage plants grown on the orchardgrass grazing pasture was larger (5.8-1.5% on a dry matter basis) than that on the tall fescue grazing pasture (3.8-2.0%). Potassium contents of the several weeds in the meadows fenced from the grazing pastures varied in the ranges of 5.9 to 1.9%. 3. Monthly change of the exchangeable soil potassium content in the orchardgrass grazing pasture was almost the same as that in the tall fescue grazing pasture. There was no significant correlation between the forage potassium content and the exchangeable soil potassium content in both grazing pastures. 4. There was a positively significant correlation at 5% level between the forage potassium content and the exchangeable soil potassium content in the orchardgrass meadow when the soil potassium content was in the range of 10 to 65 mg/100 g. However, such a significant correlation disappeared in the case that the soil potassium content was in the narrower range as 10 to 25 mg/100 g. 5. The forage potassium content in the orchardgrass grazing pasture strongly responded to the potassium application more than that in the tall fescue grazing pasture. However, the soil in the former pasture had contained enough amount of potassium to meet the requirement of the forages. These facts suggest that the forage potassium content did not act as a limiting factor for the forage growth in the orchardgrass grazing pasture.

View full abstract

In many old pastures it is important to introduce new species into the surviving sward. In this report, species selection was made for sod-seeding. Seeds and fertilizers were drilled in all experiments. Pasture grass was suppressed by grazing after sod-seeding. In a small plots experiment, eight species of grasses and legumes were compared in their adaptability for the sod-seeding both under grazing and cutting conditions. Kentucky bluegrass was dominant in the grazing pasture and orchardgrass was dominant in the meadow. Perennial ryegrass and red clover were well established in both swards in the next year of sod-seeding. Tall fescue, timothy and alfalfa could not be established in both swards. Although the establishment of orchardgrass, white clover and meadow fescue was observed in the year of sod-seeding, identification between sod-seeded plants and original plants could not be done in the next year of seeding. In the larger scale experiments, perennial ryegrass, white clover and tall fescue were sodseeded in grazing pasture, and their establishment was investigated under grazing condition. As a result, perennial ryegrass and white clover were well established, while tall fescue disappeared in grazing pasture. In conclusion, perennial ryegrass, red clover and white clover were considered to be suitable species for sod-seeding. Grazing after seeding eliminated thriving of surviving grasses, allowing the establishment of newly sod-seeded plant, despite of treading and defoliation by cattle.

View full abstract

For sod-seeding of red clover into orchardgrass or timothy dominant meadow, the supression of grass by herbicide was investigated. In experiment 1, small amount of glyphosate was sprayed for the temporary suppression of grass instead of killing them. In experiment 2, doses of paraquat, 0, 200, 300 and 500 cc/10 a were compared for the temporary suppression of grass. In experiment 3, time of sod-seeding of red clover was compared every half month from 1 June to 15 September. In preliminary experiment for spray, 30 〜 50 cc/10 a of glyphosate was found to be suitable for the suppression of grass. And much more spray of glyphosate decreased plant number of orchardgrass. Establishment of red clover drill-seeded after herbicide spraying was better in the order, paraquat 300 cc/10 a, glyphosate 50 cc/10 a, glyphosate 30 cc/10 a and no herbicide spray in experiment 1. Spray of 200 cc/10 a paraquat was found suitable for the suppression of grass in experiment 2. Establishment of red clover seeded on 1 Aug. and 15 Aug. was poor in experiment 3, and it seemed that seeding at higher mean temperature than 19℃ should be avoided.

View full abstract

The effects of cattle dung deposition on sward height and consumed herbage were investigated in a bahiagrass (Paspalum notatum Flugge) pasture rotationally grazed by Holstein heifers. For this purpose, three treatments, i.e. ND (no dung was deposited), JD (a dung pat was artificially deposited in June) and AD (a dung pat was artificially deposited in August) treatments, were applied to the pasture. The rate of dung disappearance was also examined. The outlines of results are as follows. 1. The rate of dung disappearance was considerably lower in AD treatment than that in JD treatment. 2. The sward height in JD and AD treatments generally took higher values than that in ND treatment from the end of the first grazing after the dung deposition. Such an increment in sward height due to the dung deposition continued much longer in AD treatment than in JD treatment. 3. The consumed herbage in JD and AD treatments was mostly reduced at the first grazing after the dung deposition as compared with that in ND treatment. The degree and the duration of depression in herbage consumption due to the dung deposition seemed to be larger and longer in AD treatment than in JD treatment. Further, at the grazings afterward, the consumed herbage in JD and AD treatments was usually in a similar or higher level in contrast with that in ND treatment. 4. The area where the sward height and the consumed herbage were affected by the dung deposition was larger in AD treatment than in JD treatment. 5. The annual consumed herbage in JD and AD treatments turned out to be nearly the same as that in ND treatment. But the composition of plant parts in annual consumed herbage was more or less different among the treatments.

View full abstract

The effects of cattle dung deposition on plant and litter dry matter weights were investigated in a bahiagrass (Paspalum notatum Flugge) pasture rotationally grazed by Holstein heifers. Three treatments, i.e. ND (no dung was deposited), JD (a dung pat was artificially deposited in June) and AD (a dung pat was artificially deposited in August) treatments, were applied to the pasture. 1. In JD treatment, both plant and litter dry matter weights took similar values to those in ND treatment. In AD treatment, plant dry matter weight took higher values than that in ND treatment, while litter dry matter weight took similar values to that in ND treatment. 2. Both in JD and AD treatments, degree of defoliation became lower than that in ND treatment after the dung deposition. The reduction in degree of defoliation was greater and longer in AD treatment than in JD treatment, which was considered to be related to the slower dung disappearance in AD treatment than in JD treatment. 3. From these observations, as one of the main reasons for the different cattle dung effects on plant dry matter weight between JD and AD treatments, the difference in degree of defoliation after the dung deposition was pointed out.

View full abstract

A half portion of Italian ryegrass harvested at growing stage was disintegrated and pressed to obtain green juice. Yield of green juice was 50% of the material. From the residual cake (press cake) and another portion of the material crop, sun-cured hays and silages were prepared by same methods. It took 5 days to make up hays because of a changeable weather. Both the silages were very good in quality with as low pH values as around 4 and with no butyric acid. The nutritive values of the four feeds, ryegrass hay (RH), ryegrass silage (RS) , press cake hay (PH) and press cake silage (PS) , were determined using four growing goats by 4×4 Latinsquare design. The digestibilities of crude protein, crude fat and NFE and the contents of TDN and DE were the highest in RS, similar between RH and PS and the lowest in PH. The digestibility of crude fiber was not different among the four feeds. The nitrogen retention of goats was determined and it was similar among RH, RS and PS but was significantly low in PH. Thus the hay made from the press cake was the lowest in both the digestibilities of most components and the nutritional availability of nitrogen, but the silage made from it was similar in these values to the hay made from the material crop in spite of being pressed out some nutritious nutrients before ensiling. The relationship among them will change with preparing conditions, but it is sure that ensiling is one of the best methods for preserving the press cake.

View full abstract

The behavior of cattle escaping from fence is apt to occur mainly at the time of sticking into the wire space of fence during the grazing in the pasture. It is necessary to study the fence structure to prevent the escaping as possible. The experiment in the various fence structure was carried out for two Japanese Shorthorn cows with mean withers height of 127 cm and two Japanese Black Cattle cows with mean withers height of 126 cm respectively. These fences had the post spacing of 2, 3, 4, 6, 8 and 12 m with combination of 3-barbed wire, the 4-barbed wire, the 4-combinated wire of barbed and round wire, the 5-barbed wire and the 5-wire combination. The frequency of cattle sticking increased with Japanese Black Cattle rather than Japanese Shorthorn, and with the wire combination fence than the barbed wire. The total sticking time in each fence structure was shorter as the frequency of sticking increased. The difference between each post spacing was not clear in the sticking behavior. The maximum post spacing was decided as 6 m by the investigation of mean time of sticking into each wire space in 4-barbed wire fence. Since the cattle sticking behavior of falling on one's front knees was found almost under 40 cm height in the 5-wire fences, the lowest wire height above the ground should be under about 30 cm and the wire spacing between about 30 〜 80 cm should be made stronger. The percentage of dropping the wire tension after the cattle sticked into the fence was found in the upper wire, in which the frequency of sticking increased. These dropping of wire tension was found more with Japanese Black Cattle rather than with Japanese Shorthorn and more with the combinated wire fence than the barbed one.

View full abstract

The experiment using three types of fence was carried out to grasp the fence structure to control the behavior of sticking into the fences. The 4-barbed wire fences had the post spacing of 4, 5 and 6 m. And each post spacing had three wire spacing, i.e. the conventional type with the wire spacing of 30, 30, 30, 30 ern, type I of experimental fence with 30, 25, 25, 40 cm wire spacing and type II of experimental fence with 30, 20, 25, 35 cm wire spacing. The cattle used for the experiment were two Japanese Shorthorn cows with the mean withers height of 127 cm and two Japanese Black Cattle cows with the mean withers height of 126 cm. The frequency of cattle sticking into the wire space decreased at the post spacing became narrow. These frequency also decreased in the fences of type I and II than in the conventional type, so the experimental fence with narrow wire spacing between 30 〜 80 cm height above the ground were effective. The percentage of decrease of wire tension became smaller as the sticking frequency decreased, especially in the case of type II of the fence. The maximum sticking time per head in one experiment was about 20 seconds between 30 〜 80 cm in the case of Japanese Shorthorn, and about 10 seconds below 50 cm in Japanese Black Cattle. Type II of the fence with 4 m post spacing made the sticking time shorter than the other fences. We can use the multiplied time (Σ T) of the sticking frequency (N) and the sticking time (T) into each wire space as an indicator of the fence for preventing the escape. The upper limit of Σ T was 90 seconds, in the case of each experimental time within 180 seconds, for the most effective fence. It seems that type II of experimental fence with 4 m post spacing is the most effective 4-barbed wire fence.

View full abstract