上海市组织小水产的经验和教训

小水产在上海地区来说，是指那些野生的，季节性的，地方性的，分散性大的点、虾、蟹、贝等水产品。

Effects of Irrigation on Nitrogen Metabolism and Yield of Strong Gluten Wheat

[Objective] The aim was to provide reference for the field irrigation management of high yield and quality cultivation of strong gluten wheat.[Method]Under field conditions,the effects of irrigation times on nitrogen metabolism and yield of strong gluten wheat cultivar zhengmai 9023 were studied.[Result]The results indicated that NR activity,Chlorophyll and nitrogen content in flag leaf increased with irrigation times,and the irrigation treatment had obvious advantages during middle filling stage.Grain protein content showed ＂V＂ type change with grain filling going on,and protein content decreased when irrigation times going on.There was significant difference among treatments during early stage of grain filling,and the difference became smaller in the late grain filling stage.The grain yield and protein yield increased but the protein content decreased with increasing of irrigation times.[Conclusion] Increasing irrigation times properly could improve grain yield and protein yield per unit area,but reduce the grain protein content.

Effects of Aphelenchoides besseyi Infection on Yield Traits of Different Rice Varieties (Lines)

[Objective] This study aimed to reveal the effects of Aphelenchoides besseyi infection on different rice varieties（lines）.[Method] By field observation and indoor phenotypic investigation,four conventional japonica rice varieties（lines） and japonica rice restorer line R161 under natural onset conditions were observed and analyzed.[Result] After being infected by A.besseyi,different rice varieties（lines）exhibited various symptoms.Specifically,Ning 1707,Ning 1818,Zhendao 88 and Nanjing 9108 had withered leaf tips and exhibited the symptoms of ＂small grains and erect panicles＂;japonica rice restorer line R161 only had withered leaf tips without symptoms of ＂small grains and erect panicles＂,and the withering symptoms occurred in flag leaf tip,whole flag leaf and top second leaf,respectively.After being infected by A.besseyi,all the experimental materials could sprout normally,but their plant height,panicle length,seed-setting rate and 1 000-grain weight were affected to varying degrees.In addition,after being infected by A.besseyi,various symptomatic tissues of R161 exerted different effects on rice yield.Especially,panicles with withered and twisted whole flag leaf were most affected.[Conclusion] This study provided the basis for further exploration of the damages of A.besseyi infection to rice and development of corresponding control measures.

Effects of Irrigation Quantity and Term on Waterconsumption and Yield of Winter Wheat by Wide Precision Sowing

[Objective] The aim was to research effects of irrigation quantity and term on winter wheat by wide precision sowing and to provide references and technical supports for water-saving agriculture in North China. [Methed] During 2013-2015, Jimai 22, a winter wheat cultivar, was taken as materials to explore effects of irrigation quantity and term on water consumption characters and yield of winter wheat by wide precision sowing. [Result] As irrigation water increased, water consumption and irrigation water＇s proportions were growing, but quantity and proportion of soil water consumption were both diminishing; seed yields all kept increasing upon irrigation, but water use efficiencies were decreasing. Given the same irrigation conditions, water consumption by wide precision sowing was more, but yield and water use efficiency were higher. [Conclusion] The practice of combining wide precision sowing and irrigation in jointing and flowering stages, based on yield, water use efficiency and economic profits, has the potential to create more yields and higher water use efficiency and suitable to be applied and promtoed in North China.

Effect of Nitrogen Management on Yield and Water Use Efficiency of Rainfed Wheat and Maize in Northwest China

A field experiment with four treatments and four replicates in a randomized complete block design was conducted at the Changwu Experimental Station in Changwu County, Shaanxi Province, of Northwest China from 1998 to 2002. The local cropping sequence of wheat, wheat-beans, maize, and wheat over the 4-year period was adopted. A micro-plot study using ^15N-lahelled fertilizer was carried out to determine the fate of applied N fertilizer in the first year. When N fertilizer was applied wheat （years 1, 2 and 4） and maize （year 3） grain yield increased significantly （P 〈 0.05） （〉 30%）, with no significant yield differences in normal rainfall years （Years 1, 2 and 3） for N application at the commonly application rate and at 2/3 of this rate. Grain yield of wheat varied greatly between years, mainly due to variation in annual rainfall. Results of ^15N studies on wheat showed that plants recovered 36.6%-38.4% of the N applied, the N remained in soll （0-40 cm） ranged from 29.2% to 33.6%, and unaccounted-for N was 29.5%-34.2%. The following crop （wheat） recovered 2.1%- 2.8% of the residual N from N applied to the previous wheat crop with recovery generally decreasing in the subsequent three crops （beans, maize and wheat）.

Study on Rational Irrigation for Wheat Production in Fengqiu Region: Ⅰ. Analysis of the Relation Between Soil Water Supply and Wheat Yield

A 5-year experiment on water balance was conducted in a flat rainfed wheat field with an area of 66 m×100 m in Fengqiu, Henan Province, China. Results of the experiment showed that the correlation between wheat yield and water consumption was not significant, but that between wheat yield and the ratio of water supply to Penman evaporation was significant, following a parabolic curve. The water consumption process,as well as the growing season of wheat plant, could be divided into three periods. The first (154 days) was vegetative growth period, during which the water consumption accounted for 35% of the total; the second (65 days) reproductive growth period, during which the water consumption occupied 57%, indicating the importance of water consumption in this period; and the third (5~9 days) maturation period, during which water supply was not important to yield formation. According to the statistics of meteorological data over the years in this region, the hydrological conditions of the five seasons covered a probability range of 74.8%.The results (3.46~5.63 t ha-1) indicated that the productivity of the wheat field under rainfed conditions in this region had a degree of confidence of 74.8%.

Research and application of hybrid wheat in China

Hybrid wheat is recognized as a preferred approach to improve wheat yield,and it will be a competition focus in high-tech seed industry in the future. We have made a breakthrough for the first time in creation of two-line hybrid wheat system,which reaches the world leading level in wheat research and has laid an important foundation for the future direction of the world wheat research. Similar to hybrid rice,the innovation of two-line hybrid wheat system is another achievement in science and technology. The application of hybrid wheat in China will greatly increase the food production,and make a great significance to food production and food security. This paper introduces the development process and major breakthrough of hybrid wheat in China,and the main bottleneck and countermeasures in the application of hybrid wheat.

Effects of Waterlogging in Different Growth Stages on the Photosynthesis,Growth,Yield,and Protein Content of Three Wheat Cultivars in Jianghan Plain

To maintain high wheat grain yield in areas where frequent and periodic waterlogging occurs,the effects of waterlogging on the photosynthesis,growth,yield,and protein content of three wheat cultivars,namely Xiangmai55(X55),Jingmai102(J102),and Zhengmai9023(Z9023),in four different growth stages were investigated.Experiments were conducted in specially designed experimental tanks in the middle and lower reaches of the Yangtze River during the 2012-2013 and 2013-2014 wheat growing seasons in China.Results showed that X55 was the most susceptible to waterlogging,followed by J102 and Z9023.Chlorophyll content reduction and leaf senescence,which resulted in decreased green-to-total leaf number ratio,were induced to the greatest extents by waterlogging in booting and flowering stages,followed by milky stage.Meanwhile,chlorophyll content in flag leaf,plant height were significantly decreased by waterlogging in jointing stage but effectively recovered after waterlogging withdrawal,and recovery ability varied among the cultivars.Plant biomass and grain yield were most significantly decreased by waterlogging in booting and flowering stages,followed by milky and jointing stages.Grain protein content was also considerably affected by waterlogging depending on growth stage and cultivars.The decreased grain yield caused by waterlogging was mostly due to the sharp decline in 1 000-grain mass.Waterlogging led to reduced protein yield in all growth stages in three wheat cultivars.Above all,in this experiment,waterlogging decreased grain yield significantly,and waterlogging at booting stage and flowering stage was most serious.Comparing the three cultivars,X55 was most sensitive to waterlogging.

Elimination of Foodborne Pathogens in Seafoods by Irradiation： Effects on the Quality and Shelf-Life

Animal originated contamination is the main problem of public health and causes human suffering all over the world. Nowadays, radiation technology is used on foods and yielded with positive results. Gamma radiation causes damage in the structure of bacterial DNA and cell walls. This irritation can lead to decrease in bacterial growth such as spoilage and pathogenic organisms （i.e, Salmonella spp., Bacillus cereus, Listeria monocytogenes, Yersinia enterocolitica, Staphylococcus aureus, Escherichia coli O 157：H7） by this means, increased quality and shelf-life can be obtained. However, for the maintaining organoleptic and nutritional quality, it is an obligation to achive the lowest levels of doses according to chemical, physical, microbiological properties of the product. Radiation energy can lead to radiolytic products from lipids, proteins and water which are the maj or components of seafoods. Another problem in seafood industry is quality losses at the retail and distribution. Time-temperature integrations are the major factors affecting the bacterial growth and enzymatic activity on the loss of seafood quality. The purpose of this review is to summarize the available information on the elimination of some food pathogens by irradition, which emphasize the effects of gamma irradiation on the quality and shelf-life of seafoods.

Cognitive-enhancing effects of hydrolysate of polygalasaponin in SAMP8 mice

Objectives： The aim of the study is to evaluate the cognitive-enhancing effects of hydrolysate of polyga- lasaponin （HPS） on senescence accelerate mouse P8 （SAMP8） mice, an effective Alzheimer＇s disease （AD） model, and to research the relevant mechanisms. Methods： The cognitive-enhancing effects of HPS on SAMP8 mice were assessed using Morris water maze （MWM） and step-through passive avoidance tests. Then N-methyl-D-aspartate （NMDA） receptor subunit expression for both the cortex and hippocampus of mice was observed using Western blot- ting. Results： HPS （25 and 50 mg/kg） improved the escape rate and decreased the escape latency and time spent in the target quadrant for the SAMP8 mice in the MWM after oral administration of HPS for 10 d. Moreover, it decreased error times in the passive avoidance tests. Western blotting showed that HPS was able to reverse the levels of NMDAR1 and NMDAR2B expression in the cortex or hippocampus of model mice. Conclusions： The present study suggested that HPS can improve cognitive deficits in SAMP8 mice, and this mechanism might be associated with NMDA receptor （NMDAR）-related pathways.

Genetic load in marine animals： a review

Marine invertebrates and fish are well known for their remarkable genetic diversity, which is commonly explained by large population size and the characteristic dispersive nature of their early, planktonic life history. Other potential sources of diversity in marine animals, such as a higher mutation rate, have been much less considered, though evidence for a high genetic load in marine bivalves has been accumulating for nearly half a century. In this review, I examine evidence for a higher genetic load in marine animals from studies of molecular marker segregation and linkage over the last 40 years, and survey recent work examining mutational load with molecular evolution approaches. Overall, marine animals appear to have higher genetic load than terrestrial animals （higher dn/ds ratios, inbreeding load, and segregation dis＇tortion）, though results are mixed for marine fish and data are lacking for many marine animal groups. Bivalves （oysters） have the highest loads observed among marine animals, comparable only to long-lived plants; however, more data is needed from other bivalves and more marine invertebrate taxa generally. For oysters, a higher load may be related to a chronically lower effective population size that, in concert with a higher mutational rate, elevate the number of deleterious mutations observed. I suggest that future studies use high-throughput sequencing approaches to examine （1） polymorphism in genomescale datasets across a wider range of marine animals at the population level and （2） intergenerational mutational changes between parents and offspring in crosses of aquaculture species to quantify mutation rates.