Integrated rodent management in outbreak-prone upland rice growing areas of Northern Laos

An integrated rodent management program was tested in outbreak-prone areas in three provinces of the Northern uplands of Laos (Luangprabang, Phongsaly, Houaphanh). In each province, it was replicated in six villages and associated upland rice fields; six neighboring villages served as negative controls. The program started end of 2010 and aimed at protecting the wet season rice harvest of 2011 against rodent damage. Rodent control techniques included sustained trapping, rodent-proofing of grain stores, rodent hunts and village sanitation campaigns, and biological rodent control using the protozoan parasite Sarcocystis singaporensis. The measures were embedded in a community approach, which was coordinated by provincial and district agricultural officers. Compared to the control villages, which showed on average 10.9% rat damage to ripening upland rice before harvest in 2011, and to the situation of the previous year (12.8%), rat damage was significantly reduced to an average of 4.3% in rice fields of the treatment villages. The incidence of rat-infested rice storage huts dropped significantly from an average of 86% in 2010 to 3.5% in 2011 in the treatment villages. Villagers from Houaphanh culled a total of 73,088 rodents over a period of about nine months, which included mainly black rats (Rattus rattus). Because the program phased out before harvest in 2011, potential losses due to rodents were predicted based on yield-damage relationships of the crop year 2010. The predicted average reduction of yield loss for 2011 was 55%, or 417.6 kg ha⁻¹, in the treatment villages when compared to the controls. The program implemented principles of ecologically-based rodent management (EBRM), the components of which are discussed. In conclusion, EBRM could be helpful in stemming as what was observed as high chronic rodent populations in the uplands of Laos. True outbreaks will require development of a suitable forecast system.     

Pesticide use in rice and rice–fish farms in the Mekong Delta, Vietnam

Pest management practices among rice and rice–fish farmers and their perception of problems related to pests and pesticides were surveyed in the Mekong Delta. A total number of 64 different pesticides were identified during the survey. Approximately 50% were insecticides, 25% were fungicides and 25% were herbicides. The main insecticides used were pyrethroids (42%) carbamates (23%) and cartap (19%). Non-IPM farmers used twice as many pesticides as IPM farmers. Their application frequency and the amount of active ingredient used were 2–3 times higher per crop, as compared to IPM farmers. During the last three years IPM farmers estimated that they had decreased the amount of pesticides used by approximately 65%, while non-IPM farmers said that they had increased the amount of pesticide used by 40%. Also, farmers growing fish in their rice fields used less pesticide than farmers growing only rice, as pesticides adversely affect cultures of fish. Taking a long-term perspective integrated rice–fish farming with IPM practices provides a sustainable alternative to intensive rice mono-cropping, both from an economic as well as an ecological point of view.     

Influence of paddy rice terraces on soil erosion of a small watershed in a hilly area of Northern Vietnam

Soil erosion is the main cause of soil degradation in northern Vietnam. In this study, soil erosion was measured in 2 m² field plots, a 19.1-ha sub-watershed, and a 248.9-ha main watershed in Tam Quan commune, Tam Duong district, northern Vietnam during 2 years, i.e., 2004–2005. The main watershed includes lowland paddy fields, and is representative for watersheds in the northern Vietnamese landscape. Soil erosion was measured for eight events, at all the three scales to increase our understanding of erosional processes and to assess the effects of paddy fields within the main watershed. The results show that total discharge and sediment yield in both sub-watershed and main watershed were much lower than those in the field plots. Total discharge per unit area in the main watershed was higher than in the sub-watershed, because during the growing season, the paddies are filled with water and any rainfall on them therefore becomes runoff. Sediment yield in the main watershed fluctuated, depending on the soil erosion contribution from many sub-watersheds. Annual rainfalls in 2004 and 2005 were 1,172 and 1,560 mm, respectively, resulting in corresponding total discharges of 54 and 332 mm and total soil losses of 163 and 1,722 kg ha^?1 year^?1. High runoff volumes occurred in July, August, and September, but April, June, the last 10 days of September and October, were the susceptible periods for soil erosion in the study area because of low plant cover and many agricultural activities during these periods.     

沼泽地覆膜种稻栽培技术

本文阐述了沼泽地的特点及开发种稻的可行性,同时介绍了辽宁省桓仁地区利用沼泽地开发种稻覆膜栽培技术措施。     

水稻沼液浸种壮秧增产技术

沼液是各种有机物在沼气池中经过厌氧发酵后的一种液体有机肥料。经科研部门化验分析 ,沼液不仅含有多种氨基酸、维生素、蛋白质、酶、矿物质 ,以及生长素、赤霉素等对作物生长代谢有调节作用的水溶性养分 ,而且这些营养成分基本上以速效养分形式存在。因此 ,沼液速效营养能力强 ,养分可利用率高。所含的生长素既可以促进植物根系的发育 ,又有助于植物体内的氮代谢。正常使用沼气池中的沼液具有杀灭病原菌的能力。据辽宁省盘锦市大洼县王家农场试验表明 ,用沼液浸种增产表1沼液浸种秧苗素质调查处理清水 (CK)恶苗灵(CK)24小时48小时72小时…     

Plant-parasitic nematodes in the potato growing areas of Maine

A study was conducted from October 1987 to November 1988 to accumulate data on the distribution of plant-parasitic nematodes, to examine rotation schemes and time of sampling in relation to nematode populations, and to assess the occurrence ofVerticillium spp.-Pratylenchus spp. in potato growing areas of the state of Maine.Pratylenchus penetrans andP. crenatus were encountered most frequently, with detection being 19% higher in early season (May–June) than late season (September–November). All rotation schemes supportedPratylenchus spp.Meloidogyne hapla was encountered in 14% of the early samples and 19% of the late samples. Oats-potato, potato-potato, and clover-potato supported the highestM. hapla population levels. Other nematodes detected in fewer samples and in lower numbers than the two above genera wereParatylenchus spp.,Criconemella spp.,Helicotylenchus spp. andTylenchorhynchus sp. Two plants from each of 27 fields were examined for nematode-fungus associations. Samples from 7 fields were positive forV. dahliae andP. penetrans only,V. alboatrum andP. penetrans were found in 1 field,V. alboatrum alone was detected in 1 field andP. penetrans,V. dahliae andV. alboatrum were found together in 2 fields. The detection of these nematode-fungus associations suggests that the potato early dying complex defined elsewhere in the United States may be occurring in Maine.     

茶区沼气设施的建造和使用

近几年我国茶区沼气能源发展和普及速度很快，不少省（市、区）茶区沼气普及率已高达80％以上。沼气的普遍应用，有效保护了茶区森林植被，改善了生态环境。本文特就茶区所使用沼气的性质、设施建造和安全使用知识等作一简单介绍。     

Hybrid rice heterosis and genetic diversity of IRRI and Lao rice

Glutinous and non-glutinous rice hybrids derived from IRRI and Lao PDR rice germplasm were evaluated for yield heterosis and genetic diversity based on SSR markers. Pollen and spikelet fertilities of the hybrids showed absence of effective restorer and maintainer genes in the Lao varieties for WA-CMS cytoplasm. Positive heterosis over better or male parent (Lao varieties) was observed. Hybrids derived from an IRRIs TGMS line with Lao varieties showed a great potential in hybrid rice application. Genetic diversity among the rice lines was assessed by COP and SSR markers. Cluster analysis based on the molecular markers generated three parental groups in agreement with parental pedigree information. Significant linear relation was detected between yield heterosis and marker-based genetic distance of parents.     

Genetic diversity of rice blast fungus in northern China

The characterization of population structure ofblast pathogen contributes to the rational de- velopment and the deployment of blast-resis-tant cultivars.To study the population struc- ture of blast pathogen in northern China,DNA fingerprinting of 192 blast isolates col-lected in 8 representative districts in 1996 wasconducted by using Pot 2-PCR method. Sampling sites and number of haplotypeswere listed in Table.DNA isolation,DNAamplification,and gel running were done as     

水稻机插报纸旱育秧苗技术

水稻机插秧是水稻栽培机械化的一种重要形式。在国外 ,日本、韩国等已广泛应用 ,我国的东北地区和台湾省以及大型农场应用面积也较大。目前已研制成功性能较为优良的插秧机械 ,但机插秧育苗技术有待进一步改进。现在推广的机插秧育秧技术 ,有硬盘工厂化育秧、塑料纸盘育秧以及双膜育秧等几种方式 ,这些育秧方式有的一次性投资过大 ,有的育秧烦琐 ,有的秧苗素质差 ,很难使该技术进入寻常百姓家。要适应当前我国农村的生产水平和生产方式 ,必须研究制定一套操作简便可靠的育秧技术 ,提高育秧的成功率 ,才能保证机插秧技术的大面积推广。从2000…     

强的纳米863生物助长器在水稻上的应用

强的纳米８６３生物助长器 (下简称助长器) ,是由南昌纳米高新技术开发有限公司研制开发的农用高科技产品 ,１９９９年通过省级鉴定。我县从１９９９年开始在水稻上试验示范 ,每年表现均为明显增产。为进一步探讨该助长器在水稻生产中的应用效果 ,２００１年我县继续开展了试验示范工作 ,现将有关结果归纳如下。一、试验示范方法１.小区对比试验试验安排在于田镇于田村周明恩责任田中进行 ,早稻组合为优Ｉ４０２,二晚组合为金优７７。设３个处理 :处理１为用助长器浸种催芽和大田灌水 ,处理２为用助长器浸种催芽 ,处理３为对照 (ＣＫ)。小区…     

谈节水稻作与节水灌溉技术

节水稻作是采取科学灌溉用水,提高水的利用效率。试验结果表明,在不影响水稻正常生长状态下,节水稻作可节约用水30%左右,减少了灌水作业次数,降低了成本。     

Protein and lysine digestibility and protein quality of cooked Filipino rice diets and milled rice in growing rats

The protein quality of typical rice-based menu of Filipino preschool child and adult and cooked milled rice was assessed for true digestibility (TD), biological value (BV) and net protein utilization (NPU) in growing rats. Lysine and energy digestibilities were also determined. For the preschool child diet, TD was 88.8%, BV 90.0%, and NPU 79.9%. For the adult diet, TD was 87.3%, BV 86.6%, and NPU 75.5%, whereas cooked rice had 90.0% TD, 82.5% BV and 74.3% NPU. Lysine digestibility was 95.4% for preschool child diet, 95.7% for adult diet, and 100.0% for rice. Digestible energy was 91.3% for preschool child diet, 93.0% for adult diet, and 95.3% in rice. Amino acid scores were 100.0% for preschooler diet, 92.1% for adult diet, and 62.2% for rice. Protein quality based on amino acid score corrected for TD was 88.8% for preschool child diet. 80.4% for adult diet, and 56.0% for rice. If based on lysine digestibility instead of TD, protein quality would be 7.1% higher.     

北方优质粳稻栽培技术

粳稻足北方稻区主栽品种,随着人们生活水平的提高和入世后国内国际市场的激烈竞争,加速优质粳稻生产已成为北方稻作发展的方向。种植优质粳稻一定要在栽培技术上注意与普通稻不同的地方,掌握它的技术要点,才能提高它的商品价值,拓宽市场销路。因此,笔者认为有必要就北方优质粳稻栽培技术要点向广大农民朋友和有关技术部门作一介绍,供参考之用。     

Imidacloprid concentrations in paddy rice fields in northern Vietnam: measurement and probabilistic modeling

Paddy and Water Environment - Uncertainties associated with pesticide exposure forecasts arise from many sources such as spatial and temporal variability of factors influencing pesticide behavior,...     

Plant diversity and composition of rice field bunds in Southeast Asia

Which plant species can be found on rice field bunds and what are the prevailing life forms? Which plant communities occur and what are the main environmental drivers and phytogeographic patterns shaping these communities? How do species diversity and composition differ between bunds and paddies? To answer these questions, 133 vegetation relevés using the Braun-Blanquet method were collected in lowlands and uplands of Vietnam and the Philippines between 2012 and 2015. Soil samples were collected and farmers were interviewed. Properties of soil, climate, and geography were assessed, further structural parameters, landscape heterogeneity, seasonality, management and intensity of cultivation. Hierarchical UPGMA cluster analysis and NMDS ordinations were performed to visualize variation in plant community composition and the determinants. We found 302 vascular plant species, of which 94 species are red listed by the IUCN (under category “Least concern”). Therophytes and helophytes are the prevailing life forms. Six clusters of plant communities were classified, and temperature, soil acidity, land use intensity and nutrient availability were identified (according to relevance) as explanatory variables. Bunds revealed higher species richness than paddies and bunds in mountain areas were more species-rich than those in the lowlands. We conclude that the composition of bund communities provides valuable information on environmental and biogeographical conditions of the local rice landscapes, and that it is probably the best applicable and most reliable indicator of management intensity.     

油菜茬单季稻免耕直播高产高效栽培技术

阐述了湖南省双季稻主产区,现存10万hm^2单季稻低效种植面积.引进免耕直播轻型栽培技术以后,重点抓了选用适宜的品种、大田清茬除草与整平等8项技术措施,获得了油菜和水稻高产高效.免耕直播水稻667m^2产出稻谷612 kg,比移栽稻增产3.12%,油菜增产4.68%,而且省工省力.     

油菜茬单季稻免耕直播高产高效栽培技术

阐述了湖南省双季稻主产区,现存10万 hm2单季稻低效种植面积。引进免耕直播轻型栽培技术以后,重点抓了选用适宜的品种、大田清茬除草与整平等8项技术措施,获得了油菜和水稻高产高效。免耕直播水稻667 m2产出稻谷612kg,比移栽稻增产3.12％,油幕增产4．68％,而且省工省力。