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One hundred sixty-six isolates of Fusarium spp. from domestic cereal grains, feed, and other sources were examined for their ability to produce zearalenone on autoclaved moist rice grains. They belonged to the following species (number of producers/number tested): F. roseum (9/28), F. roseum (Culmorum) (3/4), F. roseum (Gibbosum) (2/5), F. roseum (Avenaceum) (1/2), F. roseum (Scirpi) (0/1), F. tricinctum (1/4), F. tricinctum (Sporotrichiella) (0/7), F. lateritium (1/1), F. episphaeria (0/2), F. moniliforme (0/3), F. oxysporum (0/12), F. rigidiusculum (0/4), F. solani (0/4), F. splendens (0/1), F. nivale (0/2), and Fusarium spp. (15/86). Zearalenone was isolated from molded rice by ethanol extraction and purified by column chromatography. Selected isolates of F. roseum M-3-2 and F. roseum (Gibbosum) A-O-2 produced 50 to 100 mg of zearalenone per kg of rice. Increased yields (250 to 407 mg/kg of rice) were obtained by F. roseum M-3-2 when the substrate was supplemented with 1% peptone.

True F1 hybrid between diploid O. punctata and Ceylonese officinaJis (CC) was first produ-ced by the authors. The F1 hybrids within diploid O. punctata showed complete pairing in chromosomes at MI, while those between diploid O. punctata and the others (intermediate form, O. eichin-geri and Ceylonese officinalis) showed low pair-ing in mean at MI, various irregularities and complete sterility of seed. Based on the present results and other evi-dences, the authors again Propose that the genome of diploid O.punctata should be des-ignated as BB.

Out of twenty three strains ofAspergillus studied,Aspergillus oryzae BI3 was found to be the most promising and among the nine indigenous raw materials used, wheat bran and Accacia seedmeal appeared to be the best supporting media followed by Jack fruit seedmeal.

In order to examine the possibility of distinguishing rice pollen from other grasses, the sculptural details of 68 species including wild and cultivate type were studied based on the transmission electron (TEM) and phase contrast microphotographs (PCM).It was found that TEM of surface replicas might help the interpretation of phase contrast observations and might clarify the appreciation of differences in cases where a discrimination of the various types was difficult.Three types of grass pollen could be distinguished based on PCM.1. Punctate type: Grains have single spinules occurring one by one on the surface based on TEM. In this type each spinule appears as a distinct dark dot with phase contrast. Zea, Coix, Secale and sometimes Hordeum.2. Areolate (negative reticulate) type: More than three spinules appear grouped on small islands or clumps which are isolated by incised grooves based on TEM. Each spinule clump is seen as an irregularly delimited dark dot and their sculpture is areolate. Most wild grasses were studied.3. Maculate type: Mixed type of single spinules and clumps of two or three spinules. According to PCM, grains of this type are seen as indistinct punctate in lower focus but more or less indistinct areolate in upper focus. Oryza, Hordeum, Triticum and some Agropyron. Some of Bambusoidae such as Arundinaria, Chinobambusa and Sasa have grains of spinule clump type, but each clump is so small that it is seen as a indistinct dot and their sculpture is maculate.From this fact Oryza pollen can be distinguished from those of punctate and areolate types, but it is difficult to distinguish Oryza from other maculate pollen except for Hordeum and Triticum which have larger pollen than that of Oryza.

Twenty-eight-days-old seedlings of a photosensitive winter rice ( Oryza sativa L.), BAM 3, were subjected to 8 hr short photoinductive cycles for varying periods. Quantitative changes in the metabolites of the leaves, the photoreceptive organs, were recorded both in the control and treated seedlings at the ages of 29, 31, 33, 35, 37 and 39 days. Sugar content (total sugar, reducing sugar and sucrose sugar) of the seedlings following short-day induction increased with an increase in the number of photoinductive cycles and simultaneous advancement in the age of the seedlings. Sugar content was at its maximum in 35-day-old seedlings under seven consecutive photoinductive cycles. The control seedlings showed higher sugar content than that of the treated seedlings all through the period of study. The nitrogen content (total nitrogen, soluble nitrogen and protein nitrogen) was much higher in treated seedlings, at each corresponding age, than in the control seedlings. Following the photoinduction the seedlings, advancing in age, showed a gradual increase in nitrogen content, reached the maximum value with 7 photoinductive cycles and thereafter showed a gradual fall with the further increase in the dose of the treatment and the age of the rice seedlings.

Dormancy in scarified Indian rice grass seeds was partially released by kinetin. Germination percentage was highly dependent on the concentration of kinetin and peaked at 0.1 mM. Additional promotion, however, was observed in the presence of Ethrel. A synergistic or additive effect on germination by the two growth regulators was observed irrespective of whether they were applied in acetone solution or in water. ATP content, but not the activity of α-amylase or alkaline phosphatase, in the germinating seeds (24 hr) was enhanced by kinetin, ethrel or a combination of both. A synergistic effect of these two hormones on the release of dormancy in cocklebur seeds was also observed.

Endemic dental fluorosis is very common in the North Central Province of Ceylon where 55·2–77·0% of school children have mottled teeth. A fluoride concentration of as high as 9 p.p.m. has been found in this area. There is no fluoride in the water in the Central hill area. There was a striking difference in the prevalence of caries in the two areas. Although there was a good correlation between dental fluorosis and the presence of fluorine in drinking water, in some subjects the fluoride in drinking water could not explain the presence of dental fluorosis.

Ocular lesions developed in most rats fed killed rice cultures or fungal mats of Penicillium viridicatum. Lesions began after 7–14 days of feeding of the fungal diet as a slight opacity of the cornea. The opacity increased in severity over the next few days and was followed by the development of hypopyon and corneal vascularization in the more severely affected eyes. The initial histological lesions were oedema of the corneal stroma and hydropic degeneration of the corneal epithelium. These lesions were followed by interstitial keratitis, iridocyclitis, hypopyon and corneal vascularization. Involvement of the posterior segment of the eye was rare. The ocular lesions were apparently due to some mycotoxin(s) entering the aqueous humour and did not seem to be related to the presence and extent of hepatic damage nor to lesions in the accessory lachrymal glands.

Four genes were indicated for ligule colour, whereas digenic segregation was obtained for pigmentation in glume, leaf-apex-margin and midrib. Linkage between a basic-complementary gene for ligule colour (Plg) and one of the complementary genes specific for pigmentation in midrib (Plm), glume (Pg) and leaf-apex-margin (Pla) is established. This linkage group (Plg-Plm-Pg-Pla) forms part of linkage group II of Misro et al. (1966). The genes Pla and Plg are recommended for inclusion in that group.

Using the two-dimensional paper-chromatographic technique, free-aminoacid analysis was made on nine diploids and five allotetraploid species of Oryza, to study the biochemical and physiological bases of species relationships. The relationship between different species was inferred on the basis of similarity or differences in polygon patterns of aminoacids, drawn using Ellison's paired affinity values. Among the diploid species, O. sativa, O. perennis subsp. balunga, O. glaberrima and O. breviligulata showed similar polygon patterns, suggesting close relationships. The other diploid species differed in their polygon pattern, reflecting species differences. In the tetraploid species, O. alta and O. latifolia, and O. minuta, O. schweinfurthiana and O. malampuzhaensis, showed similar polygon patterns. Polygon maps of O. punctata failed to show any similarity with O. officinalis, but some similarity was observed between O. punctata and O. schweinfurthiana.

Granulomatous peritonitis from starch glove powder has been repeatedly demonstrated in laboratory animals and in man after operations. Two new cases are reported. The clinical picture is one of abdominal symptoms and fever with minimal positive physical or laboratory findings, occurring two to three weeks postoperatively. Paracentesis may be helpful in diagnosis if ascitic fluid is aspirated. At exploration there is often omental and peritoneal surface involvement with thickening, induration, and diffuse nodularity. The postoperative course is variable; ultimate recovery is the rule. Steroids have shown clinical promise in hastening recovery. Recognition of this syndrome by surgeon and pathologist is essential for proper management and avoidance of unnecessary operations. Ultimate prevention will come with the advent of a nonirritating glove lubricant. For the present, meticulous care in eliminating starch contact with the patient should minimize the development of starch granulomatous peritonitis.

Nitrogenase activity was determined in situ by repeated assays at regular intervals to compare the patterns of diurnal variations occurring in a rice field, a grassland, and a peanut field. In the rice field only one peak occurred (mid-day), whereas the other systems exhibited typical two-peak patterns, which were suspected to be induced by climatic conditions or possibly by a specific rhythm of exudation. Observed data on diurnal variations in nitrogenase activity were fitted to different models of diurnal variation comprised of computed periodic curves.

A rapid, simple test, complementary to the test for amylose content, was developed based on the consistency of a cold 4.4% milled-rice paste in 0.20 N-KOH. Consistency is measured by the length in a test tube of the cold gel held horizontally for 0.5 or 1 h. The consistency values are correlated with amylograph setback viscosity and can differentiate into three consistency types–low, medium, and high–even rice samples of similar amylose contents as long as they are between 24 to 30%.

The growth of rice seedlings (Oryza satira L.) in the presence of ethylene caused a change in the response to light of coleoptile elongation. In plants grown in air without added ethylene coleoptile elongation was promoted by red, far-red and yellow-green light only in very young seedlings; in older plants irradiation inhibited the growth of the coleoptile. The effect of growing plants in the presence of ethylene was to prolong the period during which light promoted coleoptile growth. Elongation of the first internode was inhibited by light whether or not the seedlings were grown in the presence of ethylene. A correlation existed between the growth effect of an irradiation and the initial decay rate of phytochrome which was established by the treatment. Regardless of wave length, light sources whose intensities were adjusted to produce a decay rate of about 10% per hour or less induced a moderate rate of coleoptile elongation which persisted for a relatively long period. Irradiation with red or yellow-green light of higher intensity which produced a higher rate of phytochrome decay induced a higher rate of coleoptile elongation, but growth stopped after several hours. Other observations, however, showed that one cannot establish a general simple correlation between the rate of elongation of rice coleoptiles under light and the status of measurable phytochrome in the plant.

Results of cytogenetic studies of 2 amphidiploids, O. glaberrima-sativa and O. sativa-breviligulata, are reported for the first time in the genus Oryza. All the 3 species have 2n=24 chromosomes. They were produced by treating buds of F1 stubbles with 0.1% colchicine solution.

Small particles uniform in size and shape have been consistently found in preparations of rice dwarf virus extracted from affected leaves of rice plants, Oryza sativa L., or bodies of infective leafhoppers, Nephotettix cincticeps Uhl. These particles are spherical or polyhedral in shape, approximately 70 mμ in diameter, and possess central dark areas, 40–50 mμ in diameter, which are surrounded by relatively transparent regions and outer membranes. Similar particles have been shown to exist in the cytoplasm of cells in the chlorotic portions of diseased leaves of rice plants as well as in cells of the fat body, blood, intestinal epithelium, salivary glands, and Malpighian tubules of infective leafhoppers. The particles are frequently seen in crystalline array in the cells of the infected insect and plant tissues. All the evidence secured seems to justify the conclusion that these particles are the causative virus of the rice dwarf disease. It is worthy of note that this seems to be the first recorded instance of the demonstration of a leafhopper-borne virus within sectioned cells of the vector by the electron microscope.

Subcellular particles were isolated from the phosphorus-rich portion of rice bran using a differential centrifugation in nonaqueous media. Isolated particles were characterized by high contents of phosphorus and metals and low contents of proteins. Most of the phosphorus was found as phytic acid. Chemical composition and electron microscopic observation confirmed that isolated particles were derived from the aleurone layer and were distinguished from protein bodies.

The influence of rice intake in quantity on the value of the strontium-- calcium observed ratio between bone and diet was investigated by a comparison of the OR/sub bone-diet/ value among rats feeding on rice, milk, and commercial diets. The OR/sub bone-diet/ value for the rice diet groups was close to that for the milk diet groups and significantly higher than that for the commerical diet group. The discrimination factor in gastrointestinal absorption showed a similar interrelation as that seen in the case of the OR/sub bone-diet/ value among the diet groups. The large amount of rice intake does not seem to account for the low value of OR/sub bone-diet/ observed in Japan.