还田稻草的钾素利用及其增产效应研究

为研究还田稻草的增产效应及稻草还田后水稻对钾素吸收利用情况,笔者以杂交稻粤杂889和常规稻合丰占为材料,开展了盆栽和大田试验。结果表明,稻草全量还田可以替代50%的化学钾肥,"稻草全量还田+化学钾肥减半"处理比全量施用化学钾肥增产6.55%,达显著水平,增产的主要原因是稻草还田促进了水稻的干物质积累,增加了每穗粒数。     

Genomic Sequence and Experimental Tractability of a New Decapod Shrimp Model,Neocaridina denticulata

The speciose Crustacea is the largest subphylum of arthropods on the planet after the Insecta. To date, however, the only publically available sequenced crustacean genome is that of the water flea, Daphnia pulex, a member of the Branchiopoda. While Daphnia is a well-established ecotoxicological model, previous study showed that one-third of genes contained in its genome are lineage-specific and could not be identified in any other metazoan genomes. To better understand the genomic evolution of crustaceans and arthropods, we have sequenced the genome of a novel shrimp model, Neocaridina denticulata, and tested its experimental malleability. A library of 170-bp nominal fragment size was constructed from DNA of a starved single adult and sequenced using the Illumina HiSeq2000 platform. Core eukaryotic genes, the mitochondrial genome, developmental patterning genes (such as Hox) and microRNA processing pathway genes are all present in this animal, suggesting it has not undergone massive genomic loss. Comparison with the published genome of Daphnia pulex has allowed us to reveal 3750 genes that are indeed specific to the lineage containing malacostracans and branchiopods, rather than Daphnia-specific (E-value: 10⁻⁶). We also show the experimental tractability of N. denticulata, which, together with the genomic resources presented here, make it an ideal model for a wide range of further aquacultural, developmental, ecotoxicological, food safety, genetic, hormonal, physiological and reproductive research, allowing better understanding of the evolution of crustaceans and other arthropods.     

Evaluation of Water Quality from the Perspective of Eutrophication in Lake Eğirdir,Turkey

Water, Air, &; Soil Pollution - Lake E?irdir is one of the most important freshwater resources in Turkey. The lake is located at the border of Isparta province in South West Turkey, an area...     

Yield of early white cabbage grown under mulch and non-mulch conditions with low populations of onion thrips (Thrips tabaci Lindeman)

The damage caused by Thrips tabaci to a susceptible hybrid of early white cabbage was studied in field experiments undertaken during 2004 and 2005. The three treatments tested were beds of cabbage mulched with: (1) barley straw, (2) hay, and (3) black polyethylene (PE) sheeting. Bare-soil (un-mulched) beds were used as the control treatment. One early and one late experiment were performed in both years. In the early experiments, the mulches were applied at the start of the experiment, whereas in the late experiments the soil was first covered with black polyethylene for approximately 1 month. In both years, the springs were cold and wet, and so the thrips appeared late and their numbers were low. The highest mean actual weight and trimmed weight were recorded for cabbage grown in 2005 under PE mulch (actual early: 995 g, actual late: 1184 g, trimmed early: 870 g, trimmed late: 1056 g). Year 2004 gave lower values (110g for both variables) under barley straw and hay mulch (165 g and 160 g, respectively). There was no evidence of an allelopathic effect of water extracts of either barley straw or hay.     

Assessment of the production and dispersal of faecal waste from the sea‐cage aquaculture of spiny lobsters

Despite the rapid expansion of spiny lobster aquaculture, very little is known about its potential environmental impacts. In an effort to understand the potential impacts of sea‐cage culture of spiny lobsters, the faecal output and settling velocity of faeces of spiny lobster were quantified. These data were then used in hydrodynamic modelling to assess the dispersal pattern of faecal material from two sizes of hypothetical spiny lobster farms, so that inferences about likely benthic impacts could be made by modelling different scenarios of farm stocking density and food conversion efficiency. The overall mean settling velocity of lobster faecal strands was 0.9 ± 0.05 cm s^?1. There was a positive correlation between both the weight and density of faecal strands and their settling velocity. Conversely, neither the length nor the surface area of faecal strands was correlated with the settling velocity. Hydrodynamic modelling showed that faecal material deposition mainly occurred directly beneath the sea‐cages. The density of faecal material deposition increased proportionately with higher stocking density and FCR values. Overall, the results indicate that the deposition of faecal waste from sea‐cage lobster aquaculture is unlikely to cause widespread benthic impacts when operating to the current highest commercial stocking and feeding levels.     

水稻化肥减量化栽培技术规范

从品种选择、育秧、施肥、水分管理、稻草还田和病虫草害防治等方面,介绍了水稻化肥减量化栽培技术操作规范,可在珠江三角洲双季稻高产高效栽培中应用,也可供其他稻区参考。     

Product variety in Australian snacks and drinks: how can the consumer make a healthy choice?

OBJECTIVE: To estimate the proportion of snack food and beverage choices available to an Australian consumer. DESIGN: A survey of product Nutrition Information Panels (NIP) and product labels on snack foods and beverages offered for sale. Data on nutrient content were compared with criteria from different nutrient profile systems to estimate the proportion of items conforming to a choice. SETTING: A large supermarket in metropolitan Melbourne, Australia. RESULTS: A consumer could choose from 1070 different snack foods and 863 different drinks. Flavour variety was more common in snacks (maximum thirteen per product) while variation in container size was more common for drinks (up to ten per product). Recommended serving size for snacks varied greatly (1822 % of snack foods presented for sale could be deemed by multiple criteria. Similarly, only 14healthyhealthier' snack foods and beverages, e.g. by reformulation of many products by the food industry and their presentation in smaller, standardised portion-size packaging.     

H2O2对月季平面干燥花漂白的影响

在60℃温度条件下,使用H2O2作漂白剂,研究了6种不同H2O2浓度和4种漂液pH值对红色月季平面干花漂白效果的影响.结果表明:漂液浓度越大,漂白速度越快,但超过一定浓度时对材料的损伤越大,漂液适宜浓度在15%～20%之间;随着pH值增大,漂白所用的时间缩短,但当pH值超过一定范围时,漂液开始对材料有损伤,漂液pH值在9时漂白效果最好.