Search

[Purpose] In the present study, we investigated the effects of regular aerobic training with different intensities and durations on new indices of arterial stiffness measured via an upper-arm oscillometric device. [Participants and Methods] We gathered data from 41 middle-aged and older people (age 65.0 ± 11.7 years). Participants were randomly divided into five groups: (1) 15 minutes of low intensity aerobic training (n=10); (2) 30 minutes of low intensity training (n=7); (3) 15 minutes of moderate-intensity training (n=9); (4) 30 minutes of moderate-intensity training (n=8); and (5) a non-training group (n=7). Training was conducted for 8 weeks, three times per week. Arterial pulse wave index, arterial pressure-volume index, brachial-ankle and heart-brachial pulse wave velocity, cardio-ankle vascular index, brachial and ankle blood pressure, heart rate, and peak oxygen uptake were measured before and after the intervention. [Results] All indicators of arterial stiffness and brachial and ankle blood pressure in the exercise groups were significantly lower after versus before the intervention. Peak oxygen uptake did not differ before versus after the intervention. [Conclusion] The present findings indicate that regular aerobic exercise may be important in reducing arterial stiffness regardless of the intensity or duration of aerobic exercise.

Clinical/occlusal scores and jaw-muscle EMGs were recorded in 24 TMD symptomatic (group S) and 20 normal (group N) subjects to evaluate the significance of EMG parameters and their clinical associations. Results indicated: (1) integrated EMG activity (IEMG) was larger at the rest position (RP) in anterior temporalis (Ta) but smaller at maximal voluntary clenching (MVC) in masseter (Ma) and Ta, and the ratios of IEMG at 70%MVC to the corresponding bite force (70%BF) were greater in group S; (2) mean power frequency (MPF) were almost the same in both groups but its shift was more rapid in group S; (3) silent period duration (SPD) was longer in group S; (4) asymmetry indices for SPD and silent period latency (SPL) were larger in group S; (5) muscle pain was associated negatively with IEMG at MVC and 70%BF but positively with IEMGs at RP and 70%MVC, and impaired jaw movements were associated negatively with the above EMG values; (6) muscle pain was positively associated with SPD in Ma, while joint pain and sound showed positive and negative associations with SPD, respectively; (7) associations between occlusion and EMG parameters were found more in group N. These findings verify: (1) jaw elevators in TMD may have hyper-tonic activities and a weak functional efficiency; (2) jaw muscles in TMD may become easily fatigued following a functional effort, and less relaxed following a muscle twitch; (3) the severity of pain could not be reflected in EMG activities, but impaired jaw movement may increase tonic activity and decrease functional effort; (4) TMD symptoms may alter the functional adaptation of jaw-muscle activities and occlusion.

Integrated neural responses to various amino acids were recorded from the chorda tympani (facial) nerve in C3H mice. The basic amino acids hydrochlorides L-Arg-HCl and L-Lys-HCl evoked large magnitude integrated taste responses, similar to that for NaCl, and had estimated electrophysiological thresholds of 0.0001 M. No significant difference was indicated between the response magnitudes for the L- and D-forms of the basic amino acid hydrochlorides; however, responses to the basic amino acid hydrochlorides cross-adapted with NaCl. Responses to neutral L-amino acids (Ser, Ala, Gly), which taste sweet to humans, showed higher thresholds (0.0003 M), similar to that for sucrose, and did not cross-adapt with basic amino acid hydrochlorides or with NaCl. Responses to the neutral amino acids L-Ser and L-Ala were larger than those to their D-amino acid enantiomers. The acidic amino acids L-Asp and L-Glu showed concentration-response functions different from that for HCl. Both acidic amino acids were more stimulatory than HCl at the same pH, although the responses to them were cross-adapted by HCl, indicating a pH effect. A comparison of the stimulatory effectiveness among amino acid derivatives and analogues suggested that the alpha-amino group is essential for the stimulatory effectiveness of neutral amino acids.

Decreased masticatory demands due to liquid or soft diets cause a reduction in the growth of craniofacial bones and in the development of feeding musculature, but the effects on masticatory function and jaw/tongue muscle activities are unclear. The present study was undertaken to test the hypotheses that a liquid diet feeding after weaning affects the critical-period programming of mastication and the motor performances of jaw and tongue muscles. Thirty-six male Wistar rats were divided into two equals groups at weaning and fed either a solid (solid-diet group) or a liquid (liquid-diet group) diet until they reached 50 days of age. Electromyograms (EMG) of the masseter, medial pterygoid, temporalis, anterior digastric, styloglossus, and genioglossus were recorded while animals were naturally ingesting ordinary pellets, apple cubes, and a liquid diet. It was found that: (1) a more irregular chewing rhythm, a shorter chewing sequence, and a longer chewing cycle were found in the liquid-diet group, but there were no differences observed during lapping/licking between the two groups; (2) during the chewing cycles, the EMG onset of each muscle in relation to that of the masseter in the liquid-diet group was similar to that in the lapping/licking cycles in both groups; (3) the activities of jaw elevators (masseter, medial pterygoid, and temporalis) during the chewing cycles were significantly higher in the liquid-diet group; and (4) the increase in the EMG activities of jaw elevators during pellet chewing compared with apple cube chewing was significantly weaker in the liquid-diet group, whereas such an enhancement was found simultaneously in the styloglossus in the solid-diet group, and in the anterior digastric in the liquid-diet group. These findings verify that: (1) the motor output of jaw and tongue muscles may be altered in rats fed a liquid diet after being weaned; (2) the feeding of a liquid diet to rats after being weaned may obstruct the functional transition from suckling to mastication; and (3) jaw elevators that develop without motor learning of mastication are inefficiency when performing functionally.

The effect of soluble starch (acid-modified starch) on taste intensity was investigated in human subjects. Different concentrations of sucrose (Suc), six sweeteners, NaCl, quinine–HCl (QHCl) and citric acid (Cit) were dissolved in either distilled water (DW; standard) or starch solution (test solution). The solutions were presented to naive subjects and each subject was requested to taste and compare the sweetness intensity between the standard and test solutions based on a scale ranging from +3 (enhanced) to –3 (inhibited). A greater sweetness intensity occurred with Suc at different concentration (0.1–1.0 M) dissolved in soluble starch (0.125% to 4.0%) than with Suc in DW. Similarly, five other different products of soluble starch at 0.25 and 4.0% resulted in enhancement of sweetness for 0.3 and 1.0 M Suc. With the sole exception of the taste of 0.3 M Suc, sweet enhancement did not occur with 0.43 M fructose, 0.82 M glucose, 0.82 M sorbitol, 0.0037 M aspartame, 0.0042 M saccharin-Na or 0.016 M cyclamate. Neither the saltiness of NaCl (0.01–0.3 M), the bitterness of QHCl (0.00003– 0.001 M) nor the sourness of Cit (0.0003–0.01 M) were affected by the soluble starch. These results suggest that the taste enhancing effects of soluble starch on Suc sweetness might depend not only on the taste transduction mechanism, but also on the molecular interaction between Suc and soluble starch.

Alteration in the number of taste buds on the soft palate (SP), fungiform (FF), foliate (FL) and circumvallate (CV) papillae in the common marmoset at different postnatal ages was examined histologically. After paraffin embedding, complete serial sections at 10 microm thickness were made and stained by HE. Digitized images for each section were examined carefully. The number of FF taste buds at day 1 was 334. While only 20% of all the taste buds at birth possessed a taste pore, 39% of 174 SP taste buds at day 1 possessed a taste pore. The number of taste buds with pores at day 1 was small for the center CV (19 of 59), one side CV (7 of 25), and one side FL (2 of 16). These results suggest that the functional maturation of SP taste buds may precede maturation in other areas of the tongue. The total number of taste buds increased with increasing age, reached a maximum at 2 months of age: FF, 1069; SP, 609; CV-center, 530; CV-side, 390; FL, 201, and decreased thereafter. Almost all taste buds possessed a taste pore after 2 months of age. The decrease in the number of taste buds in the oral cavity with increase in age may change taste sensitivity.

Gurmarin (10 μg/ml), a protein extracted from Gymnema sylvestre, depressed significantly (40–50%) the phasic taste responses to sugars (sucrose, fructose, lactose, and maltose) and saccharin sodium recorded from the greater superficial petrosal nerve (GSP) innervating palatal taste buds in the rat. However, no significant effect of gurmarin was observed for taste responses to NaCl, HCl, and quinine hydrochloride. Phasic responses tod-amino acids that taste sweet to humans (His, Asn, Phe, Gln) were also depressed, but gurmarin treatment was without significant effect on taste responses to d-Trp andd-Ala, six l-amino acids (His, Asn, Phe, Gln, Trp, and Ala), and two basic amino acid HCl salts (Arg and Lys). With the exception of d-Trp, these inhibitory effects of gurmarin on GSP taste responses were related to the rat's preference for these substances.

Taste bud distribution on the soft palate and within three types of tongue papillae (fungiform, foliate, and circumvallate) were examined histologically in the rat at different postnatal ages. After paraffin embedding, serial sections (10 microm) were made and stained by HE, and digitized images of each section were examined. The existence of a taste pore was used to identify mature taste buds. At birth, 53% (68 of 127 observed) of the taste buds on the soft palate, but only 14% (14 of 110 observed) within fungiform papillae, contained a taste pore. One week after birth, the number of mature taste buds increased rapidly, resulting in 90% of soft palate taste buds and 80% of fungiform taste buds containing taste pores. In contrast, no taste buds with pores were observed at birth within foliate and circumvallate papillae; however, at two weeks after birth 52% (71 of 132 observed) of the foliate and 68% (180 of 267 observed) of the circumvallate taste buds examined contained taste pores. These results suggest that taste buds within the soft palate play an important role in the detection of nutrients in the neonatal rat.

Numerous taste buds are distributed on the soft palate in mammals, and these structures are innervated by the greater superficial petrosal nerve (GSP). Although the function of these taste buds remains unclear because of the operational difficulties in accessing this nerve, it has been shown that responses to sweet substances recordedfrom the GSP in rats were specifically robust [1], which suggests that such substances produce a “sweet” sensation in the animal. Also, in the hamster, we have revealed that sugars elicited two to three times larger responses in the GSP than in the chorda tympani (CT) nerve [2]. However, many amino acids also produce a sweet sensation in humans, and preferable in mammals. Accordingly, in this experiment, to determine the gustatory responses of the GSP to various l- and d-amino acids in the rat, we recorded these and compared them with the responses of the CT.

1. The stimulatory effectiveness of amino acids and analogs on the external gustatory receptors of the carp (Cyprinus carpio L.) was investigated with extracellular electrophysiological techniques. 2. Amino acids are highly effective stimuli for the carp gustatory system. Threshold for L-proline, the most effective stimulus tested, averaged 10−8.5±0.9 (SD) mol/l. Thresholds for the other stimulatory chemicals ranged between 10−4–10−8 mol/l (Table 1). Averaged gustatory neural activity for L-proline and L-alanine increased with logarithmic increase in stimulus concentration over a wide concentration range (approximately 6–7 log units) and showed a tendency for saturation at concentrations ≧ 10−3 mol/l (Figs. 5 and 6). 3. The external taste system of the carp responded to neutral and acidic amino acids, but not to basic ones. 4. Taste responses to amino acids were highly stereospecific; the L-isomer of an amino acid was stimulatory, but the enantiomer was not (Table 2). The gustatory receptors were highly responsive to amino acids containing 3 to 4 carbon atoms having unbranched and uncharged side chains. Further, this study indicated that the α-amino group and the α-hydrogen were essential for maximal effectiveness, and that for some amino acids on ionically charged primary carboxyl group was generally unnecessary for a maximal receptor response (Table 3). 5. The molecular requirements of the neutral amino acid receptor sites for the external gustatory system in the carp appeared to be similar in general to those described in the channel catfish (Caprio 1978). 6. Due to the limited number of stimulatory amino acids, the taste receptor in the carp shows a more narrowly-tuned chemical spectrum than does the olfactory system in the same species. Additionally, the taste system of the carp is more sensitive to amino acids than the olfactory system in the same species (Table 1; Goh and Tamura 1978).

Rats accept about 1 per cent sodium chloride in larger quantity than any other concentrations and reject about 6 per cent sodium chloride. The preference and aversion behavior to salt solution were abolished after bilateral ablation of the cortical taste area. Daily intake of 1 per cent sodium chloride increased markedly after bilateral lesions of the ventromedial (VM) hypothalamus of the rat, and even 6 per cent sodium chloride was accepted a little. When the rat drunk 1 per cent sodium chloride, EEG of the lateral hypothalamus was activated, and EEG of the medial hypothalamus was activated by application of 6 per cent sodium chloride to the tongue. Evoked potentials from the medial hypothalamus, induced by electrical stimulation of the tongue, were abolished after ablation of the cortical taste area. Spontaneous unit discharges of the lateral part of the posterior hypothalamus were inhibited by application of 6 per cent sodium chloride to the tongue surface, while spontaneous unit discharges of the medial part of the posterior hypothalamus were activated when 6 per cent sodium chloride was applied to the tongue. A possible brain mechanism of the linguo-cerebro-hypothalamic system for aversion behavior to strong salt solution were discussed.

1) 除草剤の散布は, その種類, 単用, 混合の割合, 分量によつて, 雑草の種類に対する殺草反応の強弱のため, 種類別被度を大きく変化する。 例えば夏季散布で翌年の同時期には一般的に多年生の殺草効果が大きい処理区ほど被度が減少し, 裸地状態になり, 裸地が多いほど夏季1年生雑草が多年生雑草に代つて増加してくる。2) 非農耕地では一般に単剤よりも混合剤が除草効果が大きく, 供試薬剤中で効果の最大なものはATA, 2,4-D, DPA混合剤200gで, 散布後20日間で裸地状態となり, その後約1ヵ月間は同状態に保持し得, ついでATA, 2,4-D, CAT混合剤200gであつた。 チガヤ, メヒシバにはDPAの単剤およびそれが含まれた混合剤が有効であり, ヤブカラシにはATAと他剤との混合剤またはウィードン2,4-Dが効果的である。3) 2,4-Dソーダ塩は広葉雑草には効果が大きく, 全雑草に対する効果はDCMU, CAT, amibenがDPA, ATAよりやや大きい。 ATA単剤は広葉多年生雑草やスギナには効果があるが, イネ科雑草には効果が少なく, DPAはイネ科雑草には単用でもかなりの効果がある。 よつてキルジンのようにATA, 2,4-D, DPAの混合ではその効果を増大する。 また2,4,5-T, 2,4-Dのブトキシエタノールエステル型除草剤にも, イネ科雑草の茎葉からの接触的吸収のために速効的な殺草効果があつた。4) 山林原野の殺草・殺木試験では, アキノキリンソウ, オカトラノオ, アリノトウグサ, イヌガンピ, ヤマハギ, ヒサカキなどには供試各薬剤とも殺草・殺木反応が著しく, 枯死するものが多い。 またコナラ, ミズナラ, ワラビには2,4,5-T, 2,4-Dのブトキシエタノールエステル型が有効で, また両者の混合剤も効果が大きい。 しかし2,4-D, 2,4,5-Tのソーダ塩混合では効果が低い。 イヌツゲ, サルトリイバラに対してもその殺草力は小さいが, 傾向は同じであつた。5) アカマツ, クロマツ, ネズは供試薬剤中最も抵抗性が大きく, 各薬剤はいずれも効果が小さく, ただH-DD (2,4-D+DPA) の多量散布 (ネズを除く) において若干の薬害反応が見られた。

In this study about the weeds on arable lahd in Japan, the following five groups were suggested from their present geographical range, though it must be admitted that we cannot show their origin exactly. The historical consideration has also been given in this paper. 1) The recently naturalized plants have been introduced in recent year. 2) The old naturalized plants were introduced from Europe or Eurasia through China in the early stage of history. 3) Cosmopolitan. 4) The prehistoric naturalized plants were introduced from Central and South China in ancient times. 5) Native species. 1) The recently naturalized weeds on upland field : 27 species were originated from Europe, and some of the most important are as follows; Senecio vulgaris, Veronica arvensis, Cerastium visosum, Rumex Acetosella, Festuca Myuros, etc.; 5 from Eurasia, Veronica persica, etc.; 9 from Nouth America, Erigeron annuus, E. canadensis, Euphorbia supina, Oxalis Martiana, etc.; 6 from New Tropical regions or South America, Oenothera odorata, Amaranthus retroflexus, etc. 2) The old naturarized weeds: 8 species were originated from Europe. Sonchus brachyotis, Vicia sepium, V. tetrasperma, Stellaria neglecta. Polygonum nodosum, P. Persicaria, Poa annua and Polygonum lapathifolium. All these species are upland field weeds, except the latter one which is paddy field weeds. 25 species were originated from Eurasia, among them Galium spurium, Elsholtzia patrini, Lamium amplexicaule, Capsella Bursa-pastoris, Chenopodium album, etc., are in upland field, whereas the following 13 species are in paddy field, Elatine triandra, Cardamine flexuosa, Ranunculus sceleratus and the others. 3) The species of old world origin or Cosmopolitan; 27 species on upland are Stellaria aquatica, Bulbosylis barbata, Digitaris adscendens, Equisetum arvense, 0xalis corniculata, Portulaca oleracea, Amaranthus ascendens, Polygonum aviculare, etc.: 26 are found in paddy field, among them there are Bidens tripartita, MyrioPhyllum verticillatum, Nasturium palustre, Eleocharis acicularis, Hydrocharis asistica, Ceratophyllum demersum, Najas marina, etc. 4) The prehistoric naturalized species: They are originated from South eastern Asia and especially interesting because these weeds are attendant on rice plants. Among them, Eclipta alba, Dopatorium junceum, Lindernia angustifolia, L. Pyxidaria, Limnophila sesseliflora, Ludwigia prostriat, Rotala indica, Monochoria vaginalis, Eriocaulon sieboltianum, Cyperus diffomis, C. Iria, Fimbristylis miliacea, Echinochloa crus-galli var. oryzicola. etc. are most important. 5) The Japanese native species; there are endemic species and the mutual common species in Japan, Korea, China, or Siberia, etc. The former contains only two species; Pleioblastus spp. and Sagittaria Aginashi. The latter would be perhaps the native species in those days when Japanese archipelago was detached from the continent (the last part of Diluvial epoch or the early years of the Allucual epoch) The native species which can be seen in Eastern as well as Northeastern Asiatic continent are amounted about 130 species on upland field and about 90 on paddy field. The most species, however, are slightly harmuful weeds, i.e., they are grown on the bordering foot-path or in the edge of irrigation ditches. A few species are noxious. As mentioned above, most of the troublesome weeds in Japan were found among the foreign species

An extraordinary development of the paired medullary facial taste nuclei, the facial lobes, occurs in the sea catfish, Plotosus lineatus. Each of the facial lobes is divided by fiber fascicles into 5 highly distinct lobules or subnuclei, constituting 5 longitudinal columns through the lobe. Extracellular, electrophysiological recordings of neurons within the respective subnuclei of the facial lobe indicate superimposable taste and tactile neural maps organized in a somatotopic manner.

Hellekant, G. and Y. Kasahara. Salivatory fibres in the trigeminal part of the lingual nerve to the mandibular salivary gland of the monkey. Acta physiol. scand. 1973.89. 208–212. In the monkey electrical stimulation at different frequencies was applied to the peripheral ends of the centrally cut trigeminal and facial branches of the chorda-lingual nerve, while the secretion from the mandibular salivary gland was studied. It was found that a) a secretion could be elicited from the gland by stimulation of either of the two branches, b) the secretion elicited by stimulation of the trigeminal branch was slightly smaller than elicited by the facial branch. which is said to be the sole source of secretory fibres to this gland in the nerve, c) the sodium and potassium contents of the saliva elicited by the two nerve branches did not differ and were similar to that observed in human saliva.

The impulse activity in the central part of the chorda tympani nerve of the rat was recorded during mechanical stimulation of the oral region. The results obtained at a stimulation rate of 1 Hz show that a) a reflex discharge could be recorded about 6–10 ms after stimulation of the ipsilateral side of the tongue, b) stimulation of the contralateral side increased the latency by about 1–1.5 ms, c) the reflex could be evoked in animals which showed no spontaneous efferent activity in the chorda tympani nerve, d) recordings from nerve filaments showed that a filament could display spontaneous activity without being involved in the reflex, e) the lingual nerve serves as the main sensory link on the reflex to mechanical stimulation of the anterior part of the tongue, and f) the reflex evoked by stimulation of other parts of the oral region had a longer latency and less intense discharge. The results obtained at higher stimulation rate show that a) individual bursts of reflex discharge could be traced at stimulation frequencies up to 60 Hz, b) except for a moderate decrease the discharge did not disappear when stimulus frequencies of 5, 30 and 50 Hz were used.

(1) The mode of distribution was examined based on the dispersion diagram (unit area 6×6, 3×3 sq. cm.). It was calculated by means of X2-test for the deviation from the POISSON distribution, POISSON type by BLACKMAN, double POISSON type by THOMAS and POLYA-EGGENBERGER type on the important species in weed communities on various crop fields and fallow fields. (2) It is generally recognized that the distribution types of species such as Polygonium Blumei, Digitaria adsedens, Cyperus Iria, Dopatorium junceum, Rotala indica, etc. which propagate by scattering seeds were fitted satisfactorily to POISSON series of random distribution, when the, goodness of fit by means of X2-test was tested, though there were two types, one was more suitable to BLACKMAN'S value and the other to THOMAS' value, when the, value of actual density (D) to BLACKMAN'S type (m) or THOMAS type m(1+λ) were compared respectively (Table l). But the distribution of weed species including Aneilema Keisak, Eleocharis acicularis, Juncellus serotinus, which propagate by such an organ ds root, solon, rhizome, was fitted to THOMAS' type and PE type of contagious distribution. (3) It was recognized a linear relation as the fitness of MOTOMURA'S law of logarithmic series, namely, the log. number of individuals-rank and the log. weight-rank of species relation were shown on some growth stages on the weed communities in fallow field. Then before and after of these stages it was indicated L-type or S-type (Fig. 1). It is also shown a linear relation from the community including rice crop plants and weeds (Fig. 2). Such a linear relation seems to indicate a kind of the temporary stability of interspefic competition.

1) Tests were made on (1) germination of barnyard grass seed, (2) tolerance of the young barnyard plants to submergence in water, and (3) the effect of flooding on the top and root growths of the rice plants and its yield. 2) Rice plant were planted on June 28th, 1950 in concrete boxes, having glass wall on one side. On July 5th all weeds were removed and seeds and seedlings of the barnyard grass were planted between the rice plants. The amounts of water of respective boxes were adjusted to soil saturation and 5, 10, 15 and 20 cm. deep. Their conditions were held for 15 and 30 day periods and then all plots were flooded 5 cm. deep to mature. 3) With the increase in the depth of water the germination of the seeds of barnyard grass decreased. But in the laboratory, Tainubie (Echinochloa Crus-galli BEAUV. var. oryzicola OHWI) showed a considerable germination even at 15∼20 cm depth of water. 4) Many weeds that grew in paddy fields showed more or less tolerance to submergence, in water even when entirely submerged. Most of barnyard grass died after having been entirely submerged in water of 20 cm. for 15∼30 days. In the case of 15 cm. depth, a few plants survived. Barnyard grass developed the best on the saturated soil and next best in soil submerged for 5 cm. 5) Rice plants also showed considerable tolerance to water. The yield from 10∼20 cm. depth was equal to that of 5 cm. depth. As to the number of tillers, the treatment of 20 cm. of water held for 15∼30 days was momentarily poorer than the 5 cm. and rice plants tended to lodge. 6) The growth of rice plants on the saturated soil was inhibited on account of much weed growth and therefore its yield was small.

l. The crab grass occurs as a dominant weed on both thes weed potato and soybean fields. Both crops are susceptible to 2, 4-D, but the crab grass is resistant to this herbicide. Post-emergence spray of 2, 4-D on these crops, therefore, cannot be expected as a practical means. 2. During 1948 to 1951, field tests of weed control with 2, 4-D were made: (a) pre-planting treatment, (b) pre-emergence treatment and (c) between-row spray. 3. 75 to 150 grams of 2, 4-D per l0 ares were sprayed on the ridged beds, and after a rain, the sweet potato slips were planted. All of the slips took root and the growth of the crop was not retarded. Its yield equalled that of the weeded plot, with the weeds reduced to 1/1O ∼1/3 of those in the untreated plot. 4. When sweet potato slips were planted immediately after 2, 4-D was applied, the crop was severely injured, particularly in the drought year. But, those roots that were moistened and dusted with active carbon were delivered to some extent from the 2, 4-D injury. 5. The pre-emergence spray of 150 grams of 2, 4-D per 10 ares was considerably effective for the weed without decreasing the yield of soybean. A spray of more than 150 grams was injurious for the growth of the soybean. Seeds coated with active carbon prior to sowing was not injured even by the spray of 450 grams of 2, 4-D. This was attlibuted to the protecting action of the active carbon. 6. The soil treatment with 2, 4-D between the rows, after tillage, cares being taken in avoiding splash of the herbicide on foliages of the crop, was more effective on the annual weeds than pre-emergence tratment. The soybean plant was not injured by the applications of l00 grams of 2, 4-D per l0 ares on dry soil and 200 grams on moist soil. The yield decreased as the amount of 2, 4-D given increased.