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The experiment was conducted at the TAMU Agricultural Research and Extension Center at Beaumont and was designed as a RCB with 7 treatments and 4 replications. Each plot was 15 ft × 12 rows (7 inches between rows) and was surrounded by a metal barrier to prevent movement of insecticide. Plots were drill planted 26 Mar at 100 lb seed/acre. Rice emerged 11 Apr. Rice was fertilized with urea near planting (29 Mar) at 122 lb/acre, 1 d before the application of the permanent flood (29 Apr) at 122 lb/acre, and at panicle differentiation (9 Jun) at 122 lb/acre for a total of 170 lb nitrogen/acre. The permanent flood was applied 30 Apr. From planting to the application of the permanent flood, rice was flush irrigated as needed. Facet and Basagran were mixed with crop oil and applied on 22 Apr at 0.75 lb (AI)/acre for each herbicide. Karate 1EC was applied at the rate and times shown in the table with a 4 nozzle (tip size 800067, 50 mesh screens), handheld, CO, pressurized spray rig. Final spray volume was 32 gal/acre. Furadan 3G was applied at the rate and time shown in the table with a hand-held shaker. From 25 to 26 May (25-26 d after application of the permanent flood), 5, 4 inch diam × 4 inch deep soil cores (each core contained at least 1 rice plant) were removed from each plot. Rice plants in cores were washed and immature RWW recovered from the roots. Plots were harvested at maturity (27 Jul) with a small combine. Yields were adjusted to 12% moisture. Insect counts were transformed using Vx + 0.5. All data were analyzed by ANOVA.

Furadan and Payload were evaluated for control of rice water weevil at the Rice Research Station, Crowley, LA. Plots, 1.22 × 7.5 m, were individually leveed and arranged in a RCBD with 4 replicates and 4 treatments. Fertilizer was incorporated pre-plant and applied broadcast 3 wk post-flood at 50.6 kg (13-13-13) and 101.2 kg (21-0-0) N-P-K/ha respectively. Plots were drill seeded (17.5 cm row spacing) to Crowley silt loam with ‘Cyprus’ rice at 112.5 kg seed/ha on 12 May, flush irrigated 14 and 21 May, and permanently flooded 28 May. Propanil was applied at 3.34 kg/ha on 26 May using a CO2 backpack sprayer delivering 141.9 liters/ha at 1.8 kg/cm2 for weed control. Benomyl was aerially applied at 0.56 kg/ha on 28 Jun to control rice blast. Furadan 3G was applied 15 d post-flood using a hand-held shaker. Payload 15G was applied 15 d post-flood and at 2.95 kg/ha 15 and 29 d post-flood. Two randomly selected soil samples per plot were taken every 7 d starting 9 Jun and ending 21 Jul using a 10.2 × 10.2 cm core sampler. Individual samples were washed through a funnel, fitted with wire screen, into a 35 mesh screen sieve. Collected RWW larvae and pupae were floated in a saturated NaCl solution, counted and corrected for the number of rice plants per core. Effects of pesticide treatment on numbers of immature RWW were determined by ANOVA using orthogonal contrasts to separate the following mean comparisons: 1) Untreated vs Treated; 2) Furadan 3G vs Payload 15G applied once at 5.9 kg/ha and Payload applied twice a 2.95 kg/ha/application date; (3) Payload 15G applied once at 5.9 kg/ha vs Payload applied twice at 2.95 kg/ha/application. Because no significant differences in larva numbers were found among the Payload treatments, these were pooled and the following contrasts made: 1) Untreated vs Treated; 2) Furadan 3G vs Payload 15G. Analysis was performed using larval counts corrected and uncorrected for the number of plants per core, since these analyses produced similar results, only uncorrected means are presented in the table. All analyses were conducted at the 0.05 probability level.

The experiment was conducted at the California Rice Experiment Station, Biggs, in 1987 to compare RWW larval control among 3 different rates of diflubenzuron (25% WP). A RCBD was used with 4 replications of 3 rates of diflubenzuron and an untreated control. Treatment plots (6.1 × 11.3 m) were bordered on the north and south by soil levees and on the east and west by 0.7-m tall aluminum sheeting pushed 4-5 cm into the soil. Plots were flooded on 2 May and water-seeded with presoaked seed at a rate of 140 kg/ha on 4 May. Water inlet furrows were closed on 15 May, when plots received application of diflubenzuron using a CO2- pressurized sprayer equipped with a 6.1-m boom. Plants had emerged about 3 cm above the water surface at application time. Water levels receded and remained shallow (1-5 cm) until inlets were re-opened 4 wk later. At other times during the experiment, water depth was maintained at 10 cm. On 22- 23 Jun ten 10-cm diam soil cores per plot (1 plant per core) were removed. Soil was washed from the roots and the number of immature RWW (larvae plus pupae) per core was recorded. Plants removed from the cores were placed in plastic bags, frozen, and later measured and weighed. Plots were harvested by a small field combine on 29 Sep. Grain was air-dried, and yield data were corrected to a seed moisture of 21%.

The objective of the experiment was to compare RWW control among insecticide treatments. The test was performed at the California Rice Experiment Station, Biggs, in 1990 using a RCBD with 4 replications of 2 insecticide treatments and an untreated control. Treatments were applied to 0.94-m diam circular plots, each bounded by a 0.7-m tall aluminum sheet pushed 3-4 cm into the soil. Plots were established on Stockton adobe clay soil and were water-seeded at a rate of 140 kg/ha on 4 May. Stands were thinned to 50 plants per ring on 25 May. Water depth in the plots was maintained at 10 cm during the experiment. Furadan 5G was applied with a hand-held granule shaker 2 d before flooding and seeding of plots and lightly incorporated by rake into the soil. NTN 33893 240 FS was applied to seeds at a rate of 187 kg per 100 kg seed by the manufacturer before planting. Rings were open on top, allowing for natural ingress of adult RWW into the plots. Twenty-five fieldcollected parthenogenic adult RWW per ring were added on 23 May. The 2 youngest, unfurled leaves on each of 20 plants per plot were examined on 23 May (before artificial infestation), 30 May, and 5 Jun for scarring caused by adult RWW feeding. Ten, 10-cm diam soil cores per plot (1 plant per core) were removed on 22-25 Jun (1 replication per d). Soil was washed from the roots and the number of immature RWW (larvae plus pupae) per core was recorded.

An accelerated rice-breeding program was initiated in 1969 at the California Rice Experiment Station. The program is broad in scope, developing cultivars in all US market classes (long, medium, and short grains) and special purpose types (waxy and aromatics). This grower-funded rice-breeding program has released 27 new cultivars as well as improved germplasm lines. Statewide paddy rice yields have risen from 6.2 to 9.3 t/ha since 1978. The incorporation of semi-dwarfing genes, earlier maturity, and increased yield potential have contributed significantly to increases in grain yield. High experimental yields (>I1 t/ha) are routine and achieving increased increments of yield will become more difficult. After the initial shift to semi-dwarf cultivars, increasing efforts were directed toward improving adaptation to environmental stresses and grain quality. Screening and selection for cold tolerance in the form of seedling vigour for water seeding and resistance to cool temperature induced sterility at the reproductive stage are integral parts of the rice-breeding program. Progress is being made on incorporation into California rice cultivars of resistance to stem rot (Sclerotiurn oryzae Cattaneo) and aggregate sheath spot [Rhizoctonia oryzae-sativae (Swada) Mordue] from wild species and tolerance to rice water weevil (Lissorhoptus oryzophilus Kuschel). New restrictions and regulations of agronomic management practices may negatively impact rice production, creating problems in stand establishment, soil fertility, and weed, disease, and insect control. Breeding efforts to help minimise the adverse effect of these restrictions on yield and quality will increase in the future. Increased emphasis is being placed on improving milling yield and cooking and processing characteristics, and new laboratory methods are being explored to aid in evaluation and selection for grain quality.

Two experiments were conducted to compare control of RWW larvae (Experiment 1) or adults (Experiment 2) among insecticide treatments. Both tests were performed at the California Rice Experiment Station, Biggs, in 1990. Each experiment was a RCBD with 3 replications of 3 insecticide treatments and an untreated control. Treatments were applied to 0.94-m diam circular plots, each bounded by a 0.7-m tall aluminum sheet pushed 3-4 cm into the soil. Plots were established on Stockton adobe clay soil and were water-seeded at a rate of 140 kg/ha on 6 May. Stands were thinned to 50 plants per ring on 22 May. Water depth in the plots was maintained at 10 cm during the experiments. Insecticides were applied by hand-held granule dispenser. Furadan 5G was applied 2 d before seeding plots and lightly incorporated by rake into the soil. UAP 308 2G was applied on 1 Jun (Experiment 2) or 7 Jun (Experiment 1). Plots were infested naturally by RWW adults and by adding 25 field-collected parthenogenic adults per ring on 25 May (Experiment 1) or 1 Jun (Experiment 2). The 2 youngest unfurled leaves on each of 20 plants per plot were examined on 24 and 31 May (Experiment 1) and on 31 May and 4 and 7 June (Experiment 2) for scarring caused by adult RWW feeding. Ten 10-cm diam soil cores per plot (1 plant per core) were removed on 26-28 Jun (1 replication per experiment per day). Soil was washed from the roots and the number of immature RWW (larvae plus pupae) per core was recorded.

The experiment was conducted at the TAMU Agricultural Research and Extension Center at Beaumont and used RCBD with 5 treatments and 4 replications. Plot size was 14 ft × 10 ft. All plots were broadcast planted to a dry seed bed on 6 May at 120 lb seed per acre. Designated plots were sown with seed treated with NTN 33893 at 3 oz (AI)/cwt. Gustafson, Inc. treated the seed. Plots were cultipacked to help cover seed. Plots were flushed and drained as needed until application of the permanent flood on 3 Jun (21 d after rice emergence). Plots were fertilized at planting with urea at 140 lb N/acre. On 21 May plots were treated with propanil at 3 lb (AI)/acre, thiobencarb at 2 lb (AI)/acre, and bentazon at 0.75 lb (AI)/acre. Furadan 3G was applied to designated plots at 0.6 lb (AI)/acre using a hand-held shaker.

This paper reviews field measurements of evapotranspiration from rice (ET rice) in the Murrumbidgee Valley of southern New South Wales. The results are compared with US Class A open pan evaporation (E pan) at CSIRO Griffith, and with reference evapotranspiration (ETo) calculated using a locally calibrated Penman equation. Both methods (+ETrice = +Epan or +ETrice = +ETo) give good estimates of total evapotranspiration from flooded rice over the ponded season of about 5 months, from October to February. Variation between seasons in total ETo, rainfall, and ETo minus rainfall is large. Over 32 years, total seasonal ETo varied by a factor of 1.5, while rainfall varied >10-fold. The irrigation water requirement for rice +(ETo - rainfall) varied from 685 mm in 1992-93 to 1350 mm in 1990-91. This large variation highlights the need to adjust the rice water use limit (16 ML/ha or 1600 mm) on a seasonal basis, to detect and eliminate high water use paddocks where percolation to the groundwater or surface runoff is excessive (>2 ML/ha). On average, an irrigation requirement of 10.5 ML/ha is needed to replace net evaporative loss +(ETo - rainfall) for rice flooded for 5 months, October-February. Monthly totals of ETo are compared for several locations within the rice-growing areas of southern New South Wales, and differences between locations are found to be small and not significant. This reflects the strong dependence of evaporation on radiant energy, which is unlikely to vary spatially to a significant extent across the region. ETo calculated from meteorological data collected at CSIRO Griffith therefore provides a definitive basis for estimating evapotranspiration from rice in southern New South Wales. Furthermore, CSIRO Griffith has a computerised meteorological data base going back to the 1930s. Current meteorological data and historical records are readily available by contacting the Metdata Manager. Therefore, the case is made for using CSIRO Griffith ETo as the reference for estimating evapotranspiration from rice in southern New South Wales. This study provides farmers, Land and Water Management Plan groups, and policy makers with a tool that can be used, on a yearly basis, to evaluate rice paddock water use efficiency. It should be adopted to confine rice growing to the least permeable soils.

Different formula tions and application methods of the insecticide, Furadan, were evaluated for control of rice water weevil at the Rice Research Station, Crowley, LA. Plots, 1.22 × 5.47 m, were collectively leveed and arranged in a RCBD with 4 replicates and 4 treatments. Fertilizer was incorporated pre-plant and applied broadcast 3 wk post-flood at 50.6 kg (13-13-13) and 101.2 kg (21-0-0) N-P-K/ha respectively. Plots were drill seeded to Crowley silt loam (17.8 cm row spacing) with ‘Cyprus’ rice at 112.5 kg seed/ha on 12 May, flush irrigated 21 and 28 May, and permanently flooded 7 Jun. Propanil was applied at 3.34 kg/ha on 26 May using a CO, backpack sprayer delivering 141.9 liters/ha at 1.8 kg/cm2 for weed control. Benomyl was aerially applied at 0.56 kg/ha on 28 Jun to control rice blast. Foliar applications of Furadan 4F were made 3 d pre-flood at 1.14 kg/ha using a CO2 backpack sprayer delivering 141.9 liters/ha at 1.52 kg/cm2 with 80015 flat-fan nozzles on a 0.91 m boom. Furadan 4F, adsorbed onto ammonium sulfate fertilizer (N-P-K = 21-0- 0), was applied 2 wk post-flood at 1.14 kg/ha using a hand-held shaker. Furadan 3G was applied 2 wk post-flood at 0.68 kg/ha using a hand-held shaker. Three randomly selected soil samples per plot were taken 22 and 29 Jun, and 7 and 13 Jul using a 10.2 × 10.2 cm core sampler. Individual samples were washed through a funnel, fitted with wire screen, into a 35 mesh screen sieve. Collected rice water weevil (RWW) larvae and pupae were floated in a saturated NaCl solution, counted and corrected for the number of rice plants per core. Five plants per plot were measured for height immediately prior to harvesting the center 4 rows of each plot on 1 Sep using a Kubota combine. Moisture content of harvested grain was determined and then standardized to 12% for calculation of yield. Statistical analysis was performed using ANOVA succeeded by orthogonal contrasts to separate the following mean comparisons: 1) Untreated vs treated; 2) Furadan 4F foliar spray vs Furadan 4F impregnated on fertilizer and broadcast applied; 3) Furadan 3G vs Furadan 4F foliar and broadcast applied. These contrasts were performed for all collection dates except the 1st date of 22 Jun, because application of the broadcast treatments were not made until after the plots were sampled. Therefore, these plots were considered as untreated and the following contrast performed: 1) Furadan 4F foliar application vs Untreated. Additionally, RWW immature counts corrected and uncorrected for the number of plants per core were analyzed. Both analyses produced similar results; thus, only uncorrected RWW immature means are presented in the table. All analyses were conducted at the 0.05 probability level.

The experiment was conducted at the TAMU Agricultural Research and Extension Center at Beaumont and used a RCBD with 9 treatments and 4 replications. Plots were 10 ft × 12 rows (7 inches between rows) and drill planted at 100 lb seed/acre on 19 Apr. Rice emerged 2 May. Facet + Basagran were applied 21 May at 0.75 lb formulated material/acre and 0.75 qt/acre, respectively. The permanent flood was applied 7 Jun. Urea was applied at 68, 51, and 51 lb N/acre at the seedling stage, immediately before the permanent flood, and panicle differentiation, respectively. Granular carbofuran was applied with a hand shaker at the time designated in the table. Furadan 4F was applied with a 4-nozzle hand-held spray boom equipped with 800067 tips and 50 mesh screens. Final spray volume was 27.6 gal/acre and times of applications are recorded in the table. Five, 4 inch diam × 4 inch deep soil cores (each containing at least 1 plant) were removed, washed and inspected for immature RWW 22-23 d after initiation of the permanent flood. At maturity all the rice in each plot was harvested with a small combine. Yields were adjusted to 12% moisture. Data were analyzed using ANOVA and means were compared using DMRT where applicable.

The study was conducted in a commercial rice field farmed by Bill Dishman in Jefferson County, TX. The experiment consisted of 5 treatments with 4 replications arranged in a RCBD. Plot size was 16 ft × 8 ft. The field was broadcast planted at 110 lb seed/acre on 23 May and rice emerged 30 May. Nitrogen was applied at 50 lb and 100 lb/acre at planting and preflood, respectively. Phosphorus was applied at 40 lb/acre at planting. Propanil was applied preflood at about 3 to 4 lb (AI)/acre. The field was flush irrigated until 2 Jul when the permanent flood was initiated. Metal barriers were placed around all plots which were infested immediately before the permanent flood with 50 adult RWW per plot. RWW were collected from untreated, flooded rice. Granular carbofuran was applied with a hand shaker at the rates and times described in the table. Liquid treatments were applied with a 4 nozzle spray rig with 800067 tips and 50 mesh screens. Spray volume was 20 gal/acre. Rates and times are described in the table. Flowable Furadan was applied to urea by slowly pipetting the liquid onto the fertilizer in a glass jar which was continually agitated for 5 min. The carbofuran-coated urea was air dried and clumps were manually broken up and applied by hand. The carbofuran-coated urea was applied at 51 lb N/acre and 1.0 lb carbofuran/acre immediately before the permanent flood. On 27 Jul (25 d after initiation of the permanent flood) 10, 4 inch diam by 4 inch deep soil cores each containing about 1 plant were removed from each plot. Cores were washed and roots inspected for RWW larvae and pupae. Plots were not harvested because of poor and inconsistent weed control. Data were analyzed by ANOVA and where applicable means separated by DMRT.

The experiment was conducted at the TAMU Agricultural Research and Extension Center at Beaumont and was designed as a RCB with 4 treatments and 4 replications. Plots were 20 ft × 8 ft and broadcast planted at 70 lb seed/acre on 1 May. Seed was untreated (no fungicide) except that which was treated with 3 oz of NTN 33893/100 lb seed by Mobay employee Dr. Lyndon Almand. The seed-bed was cloddy and dry at planting after which plots were culti-packed to cover seed. Urea was applied at 63, 51, and 51 lb N/acre at planting, immediately before the permanent flood, and at panicle differentiation, respectively. Thiobencarb was applied pre-emergence at 4 lb (AI)/acre, and propanil and bentazon were applied at 4 and 0.75 lb (AI)/acre, respectively, 3 d before initiation of the permanent flood which was applied 24 d after rice emergence. From planting to permanent flood, plots were flush irrigated as needed. Bensulfuron methyl was applied at 1.0 oz (AI)/acre 6 d after initiation of the permanent flood. Furadan 3G was applied with a hand shaker at the times designated in the table. Five, 4 inch diam X 4 inch deep soil cores (each containing at least 1 plant) per plot were removed, washed and inspected for immature RWW 19 d after initiation of the permanent flood. At maturity, the middle 2.5 ft × 20 ft of each plot was harvested with a small combine. Yields were adjusted to 12% moisture. Where appropriate, data were transformed (Vx + 0.5) and analyzed by ANOVA.

A RCBD with 5 replications was used to compare RWW larval control among 4 insecticide treatments and an untreated control. Rice plants were grown in a greenhouse in 1 liter plastic pots (10 cm diam) filled to 50% capacity with Stockton clay loam. Soil had been sifted through a 3.2-mm mesh screen and steam sterilized. Ammonium sulfate (0.5 g/pot) was added and lightly incorporated into the soil surface with forceps. Pots were flooded to a depth of 5 cm

Two rates of GUS-IG13 (X-3G43) (formerly NTN 33893) as seed treatments were compared with carbofuran (Furadan 3 G) and an untreated check for control of RWW in ‘Newbonnet’ and ‘Lemont’ rice. The experimental design was a randomized complete block with 4 replications for each variety. Plot size was 9 rows with 17.8 cm spacing X 4.88 m. Rice was drill-seeded at 123.2 kg seed/ha 28 Apr and emerged 8 May. Propanil and thiobencarb at 3.36 kg (AI)/ha each were applied 18 and 22 May for weed control. Plots were temporarily flooded (flushed) 8 May and permanently flooded 6 Jun. Urea, 151.2 and 201.6 kg/ha, was applied in a 3-way split of 84 and 133.6 kg/ha 6 Jun and 33.6 kg/ha each on 10 and 21 Jul for ‘Newbonnet’ and ‘Lemont’ plots, respectively. Carbofuran was applied with a hand shaker 15 Jun. On 30 Jun and 7 Jul and on 2 and 9 Jul, 5, 10.2 x 10.2 cm (diam by depth) soil cores were removed from each plot of ‘Newbonnet’ and ‘Lemont’, respectively. Soil and plant roots were washed into 40-mesh screens. Screens were immersed in salt water, and RWW immatures were recovered and counted. The center 4 rows of plots were harvested on 8 Sep with a small plot combine. Reported yields were adjusted to 12% moisture.

The experiment was conducted at the Texas A&M University Agricultural Research and Extension Center at Beaumont. The experimental design was a randomized complete block with 5 treatments and 4 replicates. Each plot was 6 × 13 ft surrounded by a metal barrier to prevent contamination among plots. Plots were fertilized with urea at 110.5 lb N/acre and broadcast seeded at 100 lb seed/acre 10 May. Plots were flooded 11 May and drained 13 May. Thiobencarb at 4 lb(AI)/acre was applied 16 May. Rice emerged 18 May. Plots were flooded 26 May and drained 28 May. Propanil at 3 lb (AI)/acre and bentazon at 0.5 lb (AI)/acre were applied 7 Jun. Urea at 59.5 lb N/acre was applied 8 Jun. The permanent flood (4 inches deep) was applied 9 Jun. On 13 Jun and 18 Jun (4 d and 9 d after the onset of the permanent flood) Dimilin treatments were applied with a Devilbiss atomizer (model 152) using CO2 as the propellant. At times of application, conditions were calm. The Furadan treatment was applied 20 Jun (11 d after onset of the permanent flood) using a hand-held shaker. On 7 Jul and 8 Jul, 5 soil cores (4 inches diam by 4 inches deep) containing about 1 plant/core were randomly selected and removed from each plot. Plant roots were washed in a 40-mesh screen bucket, and RWW larvae and pupae were recovered and counted.

高冷地の長野県木曽郡開田村(標高1,150m)で,積雪・凍結条件下におけるイネミズゾウムシの越冬生態を調査した。越冬世代成虫の大部分は地表下5cmまでに生息していた。表層土中の越冬世代成虫の垂直分布は標高1,150mと420mで差がなかった。開田村では厳冬期に積雪下の表層土は凍結する。この凍結した表層土から多数の越冬世代成虫の生存個体が発見された。開田村の水田畦畔へ放飼した越冬世代成虫の生存率は64%と90%であった。開田村における1月から3月の最低気温の極値は-19°Cに低下し,積雪下の地表面の最低温度は-2°C前後であったが,高冷地の越冬場所の凍結や積雪条件は,本種の越冬個体の死亡要因にならないと考えられた。

Two rice fields were divided into 16 quadrats each. The quadrats contained levees and bay areas between levees. Analysis of variance of feeding activity of Lissorhoplrus oryzophilus Kuschel indicated that, except for a period soon after flood when clumping occurred along one side of fields, adults were rather uniformly dispersed among all quadrats within each field. However, definite clumping always occurred near levees. Activity declined rapidly to near zero within ca. 3 weeks after fields were flooded. The number of samples required to estimate mean density of young scarred leaves were relatively few (1–5) at the 25% accuracy level when populations were high enough to feed on 40–60% of the newly emerged rice leaves.

Mothers of Eastern Sudan seek or practice traditional treatment for diarrhoeal disease in their children based on their perception of causation. Fifty-six mother groups from 39 villages and 17 urban centres were surveyed in this study. The collected data were grouped by definition of diarrhoea, its perceived causes and practiced treatment thought to be appropriate. Differences were shown between the urban and rural groups. A longer list of perceived causes was obtained from rural mothers. Fumigation and use of rice water and custard were the preferred managements of urban mothers, while cautery, use of mihaya and goat's milk prevailed in rural areas. The importance of having the definition of diarrhoea cited in future studies is discussed and recommended.As part of a survey aimed at designing health education programs in Eastern Sudan, 56 mother groups from 39 villages and 17 urban centers were surveyed on the definition of diarrhea, its perceived causes, and appropriate forms of treatment. 83% of urban mothers and 82% of rural mothers understood diarrhea to refer to a change in the consistency or color of stools. Perceived causes of diarrhea included unsuitable food, teething, and exposure to cold. Rural women provided a longer list of possible causes than urban mothers, but did not cite bottle feeding, presumably because this practice is nonexistent in rural Sudan. Fumigation and use of rice water and custard were the preferred means of diarrhea management in urban areas; rural mothers preferred cautery and use of mihaya and goat's milk. Mothers in urban areas showed a greater tendency to reduce breastfeeding and the amount of fluid and food given to children during episodes of diarrhea than rural mothers. 77% of urban mothers, compared with only 13% of rural mothers, were familiar with oral rehydration sachets. 77% of urban mothers and 56% of rural mothers indicated they would seek help from the health care system is home remedies failed to treat the diarrhea. Of particular concern is that erroneous beliefs about the causes of diarrhea reflected in traditional folk medicine may retard acceptance of oral rehydration and result in inappropriate "starving" of the sick child. As long as the geographic distribution of health care remains inadequate in the Sudan, folk practices will continue to be influential, however.

In California rice fields, high densities of the aster leafhopper, Macrosteles fascifrons Stal, usually are associated with a sparse rice stand, rice plants damaged by the rice water weevil, Lissorhoptrus oryzophilus Kuschel, and abundant aquatic weed growth. Results of field experiments showed that aquatic weeds had a direct impact on aster leafhopper densities. Several of these weeds, particularly Monochoria vaginalis (Bunn. f.) Presl. and Sagittaria montevidensis Cham. and Schlecht., were preferred to rice for oviposition. A sparse rice stand or weevil-damaged plants can indirectly affect aster leafhopper populations by reducing the ability of rice to compete with weeds. The result is increased weed growth which favors the buildup of aster leafhoppers.

Lissorhoptrus oryzophilus Kuschel adults were exposed to foliage of rice, Oryza sativa L., sprayed with a triflumuron-water suspension (0.28 kg [AI]/ha) to evaluate the residual control capabilities of foliar residues and to determine the longevity of ovicidal activity. Weevils were placed on treated plants at 1, 3, 5, and 7 d following application in 1985 and at 1, 3, and 5 d following application in 1986. Significant decreases in the number of larvae occurred for day 1 through day 3 in 1985 and for day 1 through day 5 in 1986 when compared with untreated checks. A significant reduction in the eclosion of first instars was observed for up to 4 d after a 24-h adult exposure period. There were no significant differences in the number of unhatched eggs remaining in the rice sheath, but there was a trend for more eggs-27.6-55.6% more than found in the check-to be found in the treated plants. Rice plants containing O-I-d-old eggs laid by unexposed adults were placed in water removed from a field that had been treated with triflumuron. The water was removed 1, 2, and 3 d after application to evaluate the extended control capabilities of residues. Significant reductions in larval numbers occurred for day 1 only.

1)長崎県内のイネミズゾウムシ発生地帯で移植時期の異なる早期水稲,普通期水稲早植え地帯から4地点を選定しイネミズゾウムシの発生消長調査を行った。また,移植時期別の要防除密度推定のための被害解析を行った。2)イネミズゾウムシ越冬成虫の本田への侵入は移植と同時に始まるが,早期水稲では移植が早いほどそのピークも早かった。3)5月下旬～6月上旬植えの普通期早植え栽培では,いずれもピークが6月下旬で,終息は7月上旬であった。本田での生息期間は早期水稲に比べ短かった。4)長崎県においては,5月下旬までに移植される早期水稲,および普通期早植え水稲における本田でのイネミズゾウムシ成虫の要防除密度は,株当たり0.2～0.4頭と推定された。

The rice water weevil (RWW), Lissorhoptrus oryzophilus Kuschel, was studied on the rice plant introduction PI 321264 (moderately RWW resistant) and the variety ‘Saturn’ (RWW susceptible) in 1981 and 1982. PI 321264 sustained significantly ( P < 0.01) lower larval populations and was significantly ( P < 0.01) less preferred for feeding and oviposition than ‘Saturn.’ Manly's instar duration determination technique revealed that the length of each larval instar was 1.20 (I), 2.56 (II), 7.14 (III), and 10.33 (IV) days, respectively. Taylor's power equation and Iwao's distribution function strongly indicated a clumped distribution pattern for immature RWW on each rice genotype for both years. The equation logeTn = loge( D 2/ a / b – 2) + ( b – l/b – 2)loge n indicated that 15 samples of ‘Saturn’ and 19 samples of PI 3212564 are needed to estimate RWW larval populations with a relative variance of 10%.

Rice water popular in some parts of the world as a folk remedy for infantile diarrhea has recently been found to be an effective oral rehydration therapy for the acute phase of infantile gastroenteritis. The osmolality of rice water as compared to dextrose-saline (D/S) and formula milk was studied. Also examined was the effect of doubling the dilution on the osmolalities of these solutions. Results show that rice water has a very low osmolality (mean +or-SD=8.9 +or- 3.4 mOsm/kg) almost 36 times lower than that of D/S (mean +or- SD= 317.5 +or- 7.5 mOsm/kg). Furthermore the osmolality of D/S was found to vary widely from 131.0 mOsm/kg to 473.6 mOsm/kg. Doubling dilution does not result in much reduction in the osmolality of rice water which is suggestive of the fact that it may be a supersaturated solution. The ease of its preparation and its low osmolality seem to suggest that rice water may be a preferable form of oral rehydration therapy for infantile diarrhea compared to D/S and formula milk especially for outpatient use. (authors)

Indirect flight muscles in the rice water weevil, Lissorhoptrus oryzophilus Kuschel, are greatly reduced in adults during winter. Muscle regeneration occurs in the spring just before adult exodus from overwintering sites. Once adults establish themselves in a flooded rice-field, the indirect flight muscles degenerate as females begin oviposition. First-generation adults possess well-developed indirect flight muscles; they exit fields in which they develop. Large numbers fly to aestivo-hibernation sites where muscle degeneration promptly occurs. Some first-generation adults move to young rice, if available, where muscle degeneration and oviposition occurs.

The responses of Arkansas, Louisiana, and Mississippi populations of Lissorhoptrus oryzophilus Kuschel to topical application of carbofuran were studied during June, August, and October 1978 and March 1979. LD50s ranged from 4 to 12 ng/weevil, but were not significantly different ( P ≤ 0.05) from previous baseline data; however, weevils from the northern most location (Stuttgart, AK) were ca. 30% more susceptible than weevils from 4 other locations. The mean weights of all weevils collected were significantly greater ( P ≤0.05) in June and August than in October or March. The 72 h LD50 for L. oryzophilus adults treated with 9 organophosphate, carbamate, and synthetic pyrethroid insecticides ranged from 8 ng/weevil (permethrin) to 389 ng/weevil (methyl parathion). None of the compounds tested were as toxic as carbofuran (7 ng/weevil). Permethrin and fenvalerate were significantly ( P ≤ 0.05) more toxic to weevils at 16° than at 27°C.

イネミズゾウムシ個体群密度の制御機構と平衡密度について検討した。1) 越冬後成虫の産卵は1ポット当り2頭をこえると密度効果が認められ,1ポット当り8頭以上では産卵数の減少が著しかった。2) 経時的密度調査の結果より生存曲線を作成した。卵から成虫までの生存率は主として卵から若齢幼虫までの期間の生存率に支配されていること,またこの時期の死亡率は卵密度に正の依存性を示した。老齢幼虫から土繭形成までの期間の死亡率も密度依存的に変化することがみられた。3) 沿海部平坦地,内陸部平坦地,山間地の3地帯における年次別密度調査の結果では,発生後ほぼ4年目で平衡密度に達した。これらの地域別増殖曲線にロジスティク式をあてはめ平衡密度を計算したところ,沿海部平坦地では低く,山間地で高かった。

イネミズゾウムシ越冬世代成虫の越冬地における発生消長を,有効積算温度から予測する方法を以下の実験によって得た。1) 長野県下の5地点で1983年と1984年に網枠を用いて越冬世代成虫の出現時期を調査した。出現時期は年次,標高により異なり,環境温度に密接に関係していた。これらのデータを用いて,有効積算温度と累積出現個体率との関係をロジスチック式を用いて表わした。2) 異なる飼育温度下で越冬世代成虫の50%個体の摂食開始前期間を調査した。その零点は13.9°C,有効積算温度は34.4日度であった。そして,有効積算温度と摂食開始前期間を終了した累積個体率との関係をロジスチック式で表わした。また,試験管内における茎葉などへの登攀率は,摂食開始前の個体では低い傾向が見られ,摂食開始後の個体では温度の上昇に伴って高くなり,17.5°C付近で急速に高まった。3) 2月から3月に越冬地で採集した越冬世代成虫を異なる温度条件で飼育し,有効積算温度と飛翔筋が144μmに達した累積個体率との関係をロジスチック式として表わした(零点は,13.8°C)。また,同様に飼育した越冬世代成虫の死亡までの日数を調査した結果,零点は11.5°C, 50%個体の死亡までの有効積算温度は779日度となり,有効積算温度と累積死亡率との関係をロジスチック式で示した。4) 以上で得られた実験結果および実験式を用いて,越冬地における越冬世代成虫の発生消長の予測曲線を求めた。茨城県谷田部町の雑木林内での発生消長の実測値と予測値とを比較したところ,両者はおおむね適合した。

Macrosteles fascifrons Stal is associated with broadleaf weeds and sedges in California rice fields. Factors that result in a sparse rice plant density or fewer rice tillers allow greater aquatic weed growth. In factorial field experiments, rice plant and rice water weevil densities were manipulated to test the effect of timing of herbicides for controlling broadleaf weeds and sedges on aster leafhopper density. 2-Methyl-4-chlorophenoxy acetic acid, a phenoxy herbicide, is used extensively on California rice to control broadleaf weeds and sedges. The recommended time of application is 35 to 65 days after seeding. Data suggested that late applications (52 and 58 days after seeding) resulted in movement of M. fascifrons from weeds to rice in plots with a sparse rice plant density. No such movement occurred following an early application 38 days after seeding. Induced infestations of M. fascifrons in small experimental plots significantly reduced rice grain yield—ll.6% in 1980 and 12.2% in 1981—primarily by reducing the number of panicles per plant. Negative evidence is given that carbaryl, which was used to eliminate leafhoppers on control plants, did not directly affect rice grain yield. Nymphs and adults preferred senescent to green rice foliage.

In the naucorid bug, Alphelocheirus, the plastron hairs are twice as thick and nearly twice as dense (ca. 4 × 106/mm2) as they had been thought to be by previous workers. From experiments and calculations it seems clear that when the plastron is subjected to excess pressures it is wetted long before there is any question of the collapse of the hair pile itself. The plastron of Aphelocheirus is thus like the plastrons of other insects in that it is wetted long before the structures supporting the air film collapse. A plastron has been independently evolved in at least five subfamilies of the Naucoridae. A plastron is here recorded for the first time in bugs of the family Helotrephidae. It has been claimed that the plastron-bearing elmid beetles are unable to fly. Many, if not most, of these beetles fly after they emerge from their pupal cells. However, once they have begun to live under water they cease to be able to fly: the flight muscles degenerate, and this degeneration seems to be irreversible. The structure of the plastron scales of several kinds of weevils is described. The resistance of the plastron of the rice water weevil, Lissorhoptrus, to wetting at excess pressures is examined. An explanation is advanced to account for the fact that weevils and other plastron-bearing beetles that live in still waters can often swim whereas those, like elmids and dryopids, that live in running waters cannot swim.

1) 温度別に越冬後成虫を飼育し,飛翔筋(epipleu-ral muscle)の発達程度を調査したところ,飛翔筋の発育零点は13.8°Cであった。2) 越冬場所の落葉下で採集した成虫を25°C, 16L-8Dで飼育開始時から絶食させた場合は,飛翔筋はほとんど発達しなかった。食草を摂食した個体の発達した飛翔筋もその後絶食させると,絶食開始12日後ないし18日後には衰退し,細くなっていた。3) 成虫の摂食開始に関与する日長反応を25°C, 16L-8Dおよび12L-12Dで調査した。9月6日に越冬場所で採集した個体は長日条件では飼育開始4日後に50%以上の個体が摂食したが,短日条件では摂食開始前期間が遅延した。12月16日以降に採集した個体では,長日および短日条件での摂食開始前期間はほぼ1日以内となり,摂食開始前期間に関与する日長反応は消失していた。4) 25°C, 16L-8Dで飛翔開始個体数を調査した結果,飛翔開始個体は飼育開始6日後ないし8日後から観察され,50%の個体が飛翔を開始したのは9日後から12日後であった。また,累積飛翔開始個体率と有効積算温度との関係式を求めた。5) 越冬後成虫の温度別の飛翔活動性を比較したところ,25°Cおよび27.5°Cで最も飛翔個体率が高く,次いで30°C, 22.5°Cの順に飛翔個体率が高かった。20°Cでは飛翔個体率はきわめて低く,18.5°Cでは飛翔個体はなかった。6) 4月から6月にかけて雑木林内のササ上で越冬後成虫数を調査したところ,ササ上の個体数が減少する時期は,室内飛翔試験で求めた関係式による飛翔開始個体の増加する時期の推定結果とよく一致していた。

To determine whether the rice water weevil, Lissorhoptrus oryzophilus KUSCHEL, may repeat at least two generations in paddy fields in Kagoshima Prefecture, the age structure of the weevil and its infestation were surveyed in 1985 in Ibusuki City, by transplanting rice at 5 different times. Some of the first generation adults which had developed on early planted rice were confirmed to produce the second generation on rice transplanted from late June to early July.

Two benzoylphenyl ureas (BPU), alsystin and diflubenzuron, were each tested at a dosage of 0.28 kg (AI)/ha in the greenhouse and laboratory on wild-caught adults of Lissorhoptrus oryzophilus Kuschel to determine the effects of the chemicals on oviposition and immature progeny. Studies showed significant reductions in the number of immatures that developed when either BPU was applied either to rice foliage or to water (containing submerged rice stems with eggs) immediately after oviposition. Applications of either BPU to water at intervals of 5, 9, and 14 days after oviposition showed no significant reductions in numbers of immatures. There were no significant differences in numbers of eggs deposited following contact of adults with treated foliage, regardless of whether immediate or residual effects (up to 6 days) were examined. Either BPU applied to rice foliage to contact adults or to water immediately after oviposition resulted in significantly fewer first instars. First instars treated directly in a suspension of either BPU showed no mortality.

The rice water weevil ( Lissorhoptrus simplex Say) occurs in large numbers in all rice fields in Arkansas, and is the only generally distributed pest of this crop in this region. The larvae feed on the roots of rice and are frequently charged with causing great damage. In large cage experiments the yield of rice in uninfested cages was approximately 35 per cent greater than it was in cages artificially infested. The loss caused by this insect may be reduced by drainage, at the time the majority of the larvae have entered the third instar and before severe root pruning begins. Drainage should continue until the soil is thoroughly dried.

The larva of the weevil Desiantha ascita (Pascoe) (Rhyparosominae) inhabits the mud among roots of swamp plants. Its spiracles are compared with those of the rice water weevil Lissorhoptrus olryzop...

does not appear. First page follows. Introduction According to(Jones et al. (1950))3 rice was first grown commercially in California in 1912. Until recently this crop was apparently free of insect pests. As indicated by (de Ong (1922)) and (Lange et al. (1953)) there were occasional outbreaks of the rice leaf miner (Hydrellia griseola Fallen) in 1922 and 1953. In 1959 a potential rice pest, the rice water weevil (Lissorhoptrus oryzophilus Kuschel), was discovered in the northern part of the Sacramento Valley. Most of the work combining entomology and rice culture in California, however, has been concerned with the problem of mosquito breeding in rice fields. Although chironomids have long been recognized as the predominant insects in and about rice fields, it was not until 1953 that plant injury by midge larvae was reported. At this time, severe damage to rice seeds and young seedlings by feeding of the larvae was observed in the Stockton area. Sporadic evidence of injury by the larvae was noted again in 1954, but losses were less than in 1953.4 The scarcity of information concerning the Chironomidae in California, as well as the indication that some species were of economic importance in rice culture, served as the stimulus for the present investigation which was begun in 1955. The objectives were to determine which species were actually inhabitants of rice fields, the ecological niche or role they occupied, and their effect on the rice plants. The field work, which extended through the summer

Data from small-plot tests with aldrin as a seed treatment to control Lissorhoptrus oryzophilus Kuschel conducted over a 10-year period indicate development of resistance during the period 1964 through 1967. Topical applications of aldrin to adult rice water weevils from 5 locations in the rice-growing areas of Texas indicated 3 General levels of resistance in 1966.

When 48 insecticides were field tested in Louisiana as seed dressings on drill-seeded rice to control Lissorhoptrus oryzophilus Kuschel, 9 of 15 carbamates, 9 of 28 organophosphates, and 2 of 5 miscellaneous compounds significantly reduced the number of rice water weevil larvae at one or more of the test rates. However, 3 carbamates, 9 organophosphates, and 3 miscellaneous materials reduced the stand of rice significantly, and all carbamates and miscellaneous materials that controlled the rice water weevil interacted with the herbicide propanil to cause undesirable seedling leaf burn. Cblorpyrifos and Plant Protection PP-211 ( O -[2-(diethylamino)-6-methyl-4-pyrimidinyl] O, O -diethyl phosphorothioate) were the only materials that prodded significant larval control and did not reduce stand or interact with propanil to cause seedling leaf bum.

The immature stages of the rice water weevil, Lissorhoptrus simplex (Say)[†][1], are passed entirely below the water, either in or among the roots of rice and other aquatic grasses. The eggs are deposited in the roots, and the female beetles will not deposit eggs unless these roots are submerged. The small larvae feed first within the roots in which they hatch, and as they grow larger they live in the mud around the roots upon which they feed. Pupation takes place in a water-tight cocoon attached to a rootlet. The entire time required for passing the immature stages in the insectary, from deposition of the egg to transformation to the adult stage, may be as brief as 32 days and as long as 77 days. The remedial measure recommended is temporary drainage of the rice fields, allowing them to dry until the ground cracks. This is very effective in destroying the larvae. [1]: #fn-2

Carbofuran granules incorporated as a preplant soil treatment at rates from 0.25 to 1.00 lb active ingredients per acre resulted in mortality of adults of Lissorhoplrus ozyzophilus Kuschel up to 6 weeks. The toxicant was translocated to the rice leaves, and mortality resulted from feeding. Relatively little toxic effect on eggs or first-instar larvae in the leaves was noted at 1.0 lb preplant or post-oviposition treatments. Preplant surface application, soil incorporation, and a post-oviposition treatment at the 1.0-lb rate caused high mortality of larvae which may have been due to systemic or contact action.

Adults of the rice water weevil, Lissorhoptrus oryzophilus Kuschel, a relatively new pest in California, were collected during May, June, and July for seed-treatment tests in the greenhouse. The parthenogenetic females readily oviposited in the submerged portion of the leaf sheath of the rice seedlings. Plant phytotoxicity was determined and control was evaluated by recording adult mortality, presence of larvae, and plant damage. Aldrin, lindane, Kepone® (decachlorooctahydro-1,3,4-metheno-2 H -cyclobuta[ cd ]pentalen-2-one), NIA 10242 (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate), and GS 13005 ( O,O -dimethyl phosphorodithioate S-ester with 4-(mercaptomethyl)-2-methoyx-δ2-1,3,4-thiadiazolin-5-one) controlled larvae or adults or both at 8 oz of active ingredients/100 lb of seed. The 3 last-mentioned insecticides were also tested at one-half this rate, but only NIA 10242 was equally effective at the lower rate. It was not determined if control was the result of contact or systemic action of the insecticides. The 1st-instar larvae would be most susceptible to contact action when they moved from the leaf sheath past the seed to the roots to complete their development.

Different yeast strains from forests located in southern Brazil, with potential to produce carotenoids, were isolated. Three microorganisms were selected as potential carotenoid producers. Sporiodiobolus pararoseus, Rhodotorula mucilaginosa and Pichia fermentans were grown in Yeast Malt (YM) medium and the carotenoids produced identified as cryptoxanthin and β-carotene. In order to reduce production costs, agroindustrial residues were used in the formulation of medium A (parboiled rice water and crude glycerol) and medium B (parboiled rice water and sugar cane molasses). The highest carotenoid production was obtained with S. pararoseus. It reached 905.30 μ gL-1 (122.82 μg g-1) in YM medium, 820 μg L-1 (68.04 μg g-1) in medium B and 710 μg L-1 (86.46 μg g-1) in medium A. R. mucilaginosa exhibited the best performance in medium B (360 μg L-1 and 30.16 μg g-1) and a new microorganism - P. fermentans - reached 48% (medium A) and 78% (medium B) of the value found in YM medium. Therefore, the agroindustrial residues under evaluation, which replaced the commonly used nitrogen and carbon sources in culture media, enabled the isolated yeasts to yield carotenoids.

The paper firstly analyzed meteorological influences on rice water requirement referring to temperature, wind speed, air saturation deficit and sunshine hours. Then, it analyzed the other meteorological factors’ influences. Through introduction of natural water surface evaporation factor, a multivariable linear equation with five variables was established for rice water requirement. A five variable linear equation model, FAO56 Penman-Monteith formula and a four variable linear equation which don’t have natural water surface evaporation factor were used to calculate rice water requirement in cold areas. It shows that multivariable linear equation with five variables has a more accuracy, compared with Penman-Monteith formula and four variable linear equation. As a regional empirical formula, the five variable linear equation can be applied in cold area.

The relationship of water-fertilizer and yield is the theory basis of improving water-fertilizer use efficiency and reducing fertilizer pollution. Based on analyzing a lot of experimental data, 3 fertilizer factors involving N, P, K were introduced in the growth stage model of rice water-fertilizer production function and dynamic production function model. The former is called Jensen model and the latter is called modified Morgan model. The two models have higher correlation coefficients, can correctly reflect interaction relationship between rice growth and water-fertilizer (N, P, K), accurately simulate continuous dynamic traits of rice growth and can forecast rice yield according to the amount of N, P, K applied. In addition, Modified Morgan model has a much higher correlation coefficient than Jensen model.

A mermithid nematode parasite was observed in rice water weevils in the Stuttgart, Ark., area 1973–1976. Intensive observations for one season indicated that the nematode caused weevil mortality and reduced weevil egg production. The nematode was found almost exclusively in female weevils. Peak abundance occurred the last of June with a small 2nd peak in early Aug.

In large-field tests, a single broadcast application of carbofuran 3% sand-core granules at a rate of 0.5 lb AI/acre applied once at 2 or 3 wk after the rice seedlings were flooded reduced populations of larvae of Lissorhoptrus oryzophilus Kuschel by 81 and 88%. Also, in small-plot tests, populations of small-and medium-sized larvae were reduced 69 and 73%, respectively, within 11–14 days after treatment, and 70% of the large larvae were killed by 18–21 days after treatment. All plots treated with carbofuran yielded 86–614 lb more rough rice/acre than untreated checks.