Comparative studies of some prominent her cultivars for their qualitative characters ( Ziziphus jujuba L.)

Various ber cultivars differ grearly from each other-with regard to physio-chemical characteristics,some are superior for one character while others are best for another character.Umran No.9 showed largest fruit size,maximum fruit weight and best keeping quality.This variety was also found best for better seed/pulp ratio.Tile variety Khathi mithi was found best for organoleptic values and non reducing sugars.Gohr variety was found superior to other varieties when evaluated for total soluble solid,acidity,ascorbic acid and reducing sugars.     

Content and evaluation system of planning regional agriculture park system——a case study of Kunming City

以昆明市域农业园区体系规划为例,提出了区域农业园区体系规划成果框架.区域农业园区体系规划应以规划背景与条件分析为基础,提出规划总则与发展目标.区域农业园区体系的规划布局主要包括农业园区的产业布局规划、空间结构规划、等级和规模结构规划、职能结构规划.区域内园区建设发展分类引导规划、农业园区基础设施规划和近期重点建设项目规划也是区域农业园区体系规划的重要内容.区域农业园区建设的体制创新、产业创新、制度创新、管理模式和运行机制创新,是建设现代农业园区的重要保障.区域农业园区评价体系建设的重点是建立科学合理的综合评价指标体系及其相应的评价程序与操作方法.     

Development of a sensitive and reliable droplet digital PCR assay for the detection of ‘Candidatus Liberibacter asiaticus'

Citrus Huanglongbing(HLB, yellow shoot disease) is one of the most serious citrus diseases worldwide. To better improve the detection sensitivity, a droplet digital PCR(ddPCR) assay was developed for the rapid detection of ‘Candidatus Liberibacter asiaticus'(Las), the putative causal agent of HLB. The detection of sensitivity comparison using positive plasmid indicated that dd PCR was superior to quantitative PCR(qPCR) for detecting and quantifying Las at low concentrations. The Las detection of 40 field samples also showed that six of 13 asymptomatic samples(46.15%) with high Ct value(35) were positive by dd PCR. This methodology showed great potential for early HLB infection diagnosis.     

Development and Application of a Diagnostic Kit for Detecting NDV

根据新城疲病毒(NDV)对鸡红细胞的凝集以及相应抗体对病毒血凝的抑制的原理设计出新城疫抗体监测试剂盒,主要用于鸡新城疫抗体水平的监测,为正确实施新城疫疫苗适时接种提供依据。试剂盒包括新城疫阳性血清、新城疲阴性血清、4单位新城疫抗原和10ml/L醛化红细胞。经对50多份血清检测结果表明,用于血凝(HA)和血凝抑制(HI)试验的醛化红细胞与新鲜红细胞无显著性差异(P>0.05),试剂盒能准确检测出鸡群新城疫抗体水平,具有操作简便,适用,易于保存等特点。     

Establishment of an efficient regeneration and genetic transformation system for Malus prunifolia Borkh. ‘Fupingqiuzi’

Malus prunifolia Borkh. ‘Fupingqiuzi’ has significant ecological and economic value and plays a key role in germplasm development and resistance research. However, its long juvenile phase and high heterozygosity are barriers to the identification of ‘Fupingqiuzi’ progeny with excellent traits. In-vitro regeneration techniques and Agrobacterium-mediated genetic transformation systems can efficiently produce complete plants and thus enable studies of gene function.However, optimal regeneration and...     

A rapid multiplication system for ‘Candidatus Liberibacter asiaticus’ through regeneration of axillary buds in vitro

‘Candidatus Liberibacter asiaticus (CLas)’, which causes citrus Huanglongbing (HLB) disease, has not been successfully cultured in vitro to date. Here, a rapid multiplication system for CLas was established through in vitro regeneration of axillary buds from CLas-infected ‘Changyecheng’ sweet orange (Citrus sinensis Osbeck). Stem segments with a single axillary bud were cultured in vitro to allow CLas to multiply in the regenerating axillary buds. A high CLas titer was detected in the regenerated shoots on an optimized medium at 30 days after germination (DAG). This titer was 28.2-fold higher than in the midribs from CLas-infected trees growing in the greenhouse. To minimize contamination during in vitro regeneration, CLas-infected axillary buds were micrografted onto seedlings of ‘Changyecheng’ sweet orange and cultured in a liquid medium. In this culture, the titers of CLas in regenerated shoots rapidly increased from 7.5×10⁴ to 1.4×10⁸ cells μg^–1 of citrus DNA during the first 40 DAG. The percentages of shoots with >1×10⁸ CLas cells μg^–1 DNA were 30 and 40% at 30 and 40 DAG, respectively. Direct tissue blot immunoassay (DTBIA) indicated that the distribution of CLas was much more uniform in regenerated plantlets than in CLas-infected trees growing in the greenhouse. The disease symptoms in the plantlets were die-back, stunted growth, leaf necrosis/yellowing, and defoliation. The death rate of the plantlets was 82.0% at 60 DAG. Our results show that CLas can effectively multiply in citrus plantlests in vitro. This method will be useful for studying plant-HLB interactions and for rapid screening of therapeutic compounds against CLas in citrus.     

Development and evaluation of the carbon–nitrogen cycle module for the GPFARM-Range model

Rangelands cover approximately 50% of the terrestrial surface of the earth. Consequently, the soil carbon and nitrogen storage and turnover in rangeland systems are becoming increasingly important for sustainable grazing management and climate change. In this study, a carbon–nitrogen (C–N) cycle module from the N Leaching and Environmental Analysis Package (NLEAP) was added into the GPFARM-Range model. This linkage was tested against a 14-year forage dataset (1993–2006) with measurements of C and N in 1993, 2003, and 2006 near Cheyenne, WY. The results showed that the peak standing crop (PSC), and changes in soil organic carbon (SOC) and total soil organic nitrogen (TON) in the rangeland were reasonably simulated by the new GPFARM-Range model. The indices of agreement (d) were >0.85 and the mean bias errors (MBE) were <130 kg ha⁻¹ for the PSC simulation. The SOC and TON in the soil profile were simulated with relative root mean squared error (RRMSE) <5% for the calibration treatment without grazing and <20% for the validation treatments with grazing, both showing no significant bias or error from the observed values. A sensitivity analysis showed that the model responded reasonably to changes in temperature and precipitation. A long-term dataset with more soil C and N measurement events on the rangeland is needed to further test the model, but it is not available at this time. Additional investigation is needed into the adequacy of root-to-shoot ratio approaches to simulate root growth for forage groups in these systems.     

Development of a PCR Diagnostic Kit for Cryptosporidium andersoni in Dairy Cow

Cryptosporidiosis is an important zoonosis caused by the Cryptosporidium species. To develop a PCR diagnostic kit for molecular detection and differential diagnosis of Cryptosporidium spp., a portion of ITS-1 sequence of Cryptosporidium. andersoni was chosen as the target DNA for designing the species-specific primers （ZRQF/ZR）. The kit components were determined after the PCR amplification conditions were serially optimized. A series of tests were conducted in the specificity, sensitivity, stability, reproducibility, and stored period of the kit, respectively. The results showed that only C. andersoni were amplified specific band of about 500 bp, while Cryptosporidium. parvum, Cryptosporidium. baileyi, Eimeria sp of dairy cow, Toxoplasma gondii, Eimeria sp of pig, Ascaris suum, Cyclospora sp, and E. coli could not be amplified. 254 oocysts of C. andersoni was the lowest number that could be detected using the kit. The kit worked well after being stored at room temperature, 4 and -20℃ for nine months. Fecal specimens, which were collected from a total of 243 calves on four different dairy farms in Guangdong Province, China, and one dairy farm in Henan Province, China, were examined using the kit; the positive rate of the kit was 2-13% higher than that of the routine methods. The results indicated that the kit can detect fecal samples faster, more sensitively, and conveniently, and can provide a useful tool for the identification and differentiation of C. andersoni from the other Cryptosporidium species; it also has implications for further studies on molecular epidemiology and differential diagnostics of cryptosporidiosis in animals.     

Using a mobile phone Short Messaging Service (SMS) for irrigation scheduling in Australia – Farmers’ participation and utility evaluation

Irrigation scheduling Decision Support Systems (DSS) have seen poor uptake despite proved usage benefits. The failures of some previous systems with proven model accuracy and water savings ability have been attributed to interface difficulties and inappropriate information for end users. Use of the mobile phone Short Messaging Service (SMS) text messages was trialed as an interface to overcome these difficulties. Irrigation system dripper run time scheduling advice was sent daily to 72 Australian irrigators’ mobile phones from a water balance system called IrriSatSMS. Irrigators sent back information on irrigations and rainfall, also via SMS, to update the water balance. This trial showed that a complex, water balance-based, DSS could rely on SMS as the sole interface.All 72 irrigators involved were content to receive messages daily for the entire growing season (200 days). A measure of engagement and utility of the system was determined by those who returned their irrigation and rainfall data; 45 sent in their data all season, 13 for half the season and 14 never sent in any data. Thus we infer that 45 users (63%) found the SMS system of enough utility to use for the whole season. Also, at end of season, 6 of the 13 who had stopped half way through said that in retrospect they wished they had not. Thus overall 80% of irrigators found the system useful.User interview data showed the simplicity of use, advice and the prompting effects of intrusive delivery (phone ringing) were key features in the resultant strong engagement of irrigators. Success also relied on appreciating that irrigators will only use objective decision support advice as one element in a set of decision making tools that include subjective and unquantifiable elements, such as plant appearance.This strong uptake reverses the trend in irrigation decision support which has seen poor uptake of sophisticated systems that produce comprehensive scheduling support but which are, or are perceived to be, complex and time consuming to use. Additionally, high participation rates show that much model input data may be collected from irrigators via SMS so it can be used as a very cheap bi-directional communication channel.     

Use of Hypocrea jecorina (anamorph Trichoderma reesei) as a model system for Trichoderma biocontrol of Pythium blight identifies new targets for genetic strain improvement

Biocontrol by Trichoderma has been studied mainly with selected isolates of T. harzianum, T. atroviride and T. asperellum, which are members of sections Pachybasium and Trichoderma. In contrast, species from section Longibrachiatum have only rarely been studied. On the other hand, one taxon from this section-Hypocrea jecorina (anamorph: Trichoderma reesei)-has been widely used for the production of cellulolytic and hemicellulolytic enzymes and recombinant proteins. As far as T…     

Assessment of the optimal spectral bands for designing a sensor for vineyard disease detection: the case of ‘Flavescence dorée’

Precision Agriculture - Disease detection and control is one of the main objectives of vineyard research in France. Manual monitoring of diseases is a time consuming operation especially when...     

早熟欧李新品种‘夏日红’的选育(英文)

‘夏日红’是2006年从自然杂交实生后代中选育而成的早熟型欧李新品种。果实扁圆形,果皮红色,果肉黄色,味酸甜;平均单果质量6.74 g,半离核。果实可溶性固形物含量达10.9%,总糖含量8.20%,总酸含量1.81%,糖酸比4.53,可食率94.51%。果肉含钙219.7 mg/kg,铁4.4 mg/kg,锌1.09 mg/kg,维生素C 182 mg/kg。果实发育期96~101 d,北京地区7月下旬成熟;货架期3~5 d,冷藏20 d左右,冷冻可达1a,果实不失味。适合北京地区栽培,第二年开花结果,丰产性较强。     

美国佛罗里达种植者协会推荐2009年新品种(四) 凤梨‘Glossita’和‘Fusion’

上期我们为大家介绍了美国佛罗里达种植者协会推荐2009年新品种彩叶凤梨‘Voodoo Doll’和‘Magali’,本期为大家介绍的是来自荷兰Corn.Bak公司的凤梨‘Glossita’和‘Fusion’。凤梨‘Glossita’是荷兰Corn.Bak公司新推出     

‘Extended spectral angle mapping (ESAM)’ for citrus greening disease detection using airborne hyperspectral imaging

Hyperspectral (HS) imaging is becoming more important for agricultural applications. Due to its high spectral resolution, it exhibits excellent performance in disease identification of different crops. In this study, a novel method termed ‘extended spectral angle mapping (ESAM)’ was proposed to detect citrus greening disease (Huanglongbing or HLB), which is a very destructive disease of citrus. Firstly, the Savitzky–Golay smoothing filter was used to remove spectral noise within the data. A mask for tree canopy was built using support vector machine, to separate the tree canopies from the background. Pure endmembers of the masked dataset for healthy and HLB infected tree canopies were extracted using vertex component analysis. By utilizing the derived pure endmembers, spectral angle mapping was applied to differentiate between healthy and citrus greening disease infected areas in the image. Finally, most false positive detections were filtered out using red-edge position. An experiment was carried out using an HS image acquired by an airborne HS imaging system, and a multispectral image acquired by the WorldView-2 satellite, from the Citrus Research and Education Center, Lake Alfred, FL, USA. Ground reflectance measurement and coordinates for diseased trees were recorded. The experimental results were compared with another supervised method, Mahalanobis distance, and an unsupervised method, K-means, both of which showed a 63.6 % accuracy. The proposed ESAM performed better with a detection accuracy of 86 % than those two methods. These results demonstrated that the detection accuracy using HS image could be enhanced by focusing on the pure endmember extraction and the use of red-edge position, suggesting that there is a great potential of citrus greening disease detection using an HS image.     

‘紫枝’玫瑰(Rosa rugosa ‘Zi zhi’)开花过程花青素相关化合物及代谢途径分析

【目的】分析‘紫枝’玫瑰5个开花时期花瓣中的花青苷、类黄酮苷和类胡萝卜素的种类和含量,推定‘紫枝’玫瑰花的花青苷代谢途径,为探讨玫瑰花色的呈色机理和花色育种提供参考。【方法】以‘紫枝’玫瑰不同开花时期的花瓣为试材,用高效液相色谱(HPLC)和超高效液相色质联用分析法(UPLC-DAD-Q-TOF-MS)对其花青苷、类黄酮苷和类萝卜素进行结构推定和定量分析,结合化学反应过程推测‘紫枝’玫瑰花青苷代谢途径。【结果】在‘紫枝’玫瑰中鉴定出8种花青苷、16种类黄酮苷和β-胡萝卜素,没有检测到叶黄素;花青苷主要以芍药素、飞燕草素、矢车菊素和天竺葵素的双糖苷为主,四类花青苷都在花蕾期和初开期相对含量最高;检测到芍药苷的两种甲基化衍生物,没有发现飞燕草苷的甲基化衍生物;类黄酮苷以槲皮素和山萘酚的糖苷化、酰基化和甲基化的衍生物为主。定量分析显示,芍药苷和飞燕草苷占‘紫枝’玫瑰总花青苷含量的90%以上;芍药苷含量在‘紫枝’玫瑰开花过程中随花色变浅而降低,飞燕草苷在开花过程含量变化不大;芍药苷和飞燕草苷的比例(Pn/Dp)随花色变浅而降低。【结论】‘紫枝’玫瑰花中含有芍药素、飞燕草素、矢车菊素和天竺葵素,这四类花青素在半开期之前完成全部积累,盛开期后只降解不合成。芍药素是形成‘紫枝’玫瑰花色的主要成分。‘紫枝’玫瑰的花青苷代谢途径中,甲基酶(Rr AOMT)的催化作用有底物特异性。     

A joint use of emergy evaluation,carbon footprint and economic analysis for sustainability assessment of grain system in China during 2000–2015

The rapid growth of grain yield in China accelerates a discussion on whether the grain system in China is sustainable. To answer the question, a comprehensive assessment from economic and environmental points is necessary. This study jointly used economic analysis(ECA), emergy evaluation(EME) and carbon footprint(CF) to analyze the environmental and economic sustainability of the grain production system in China based on the national statistical data during 2000–2015. Results showed that the costs of maize, wheat, rice and soybean had increased by 252-346% from 2000 to 2015, causing the lower profit of grain system in recent years. The situation resulted in a serious problem on economic sustainability of grain system in China. Meanwhile, the emergy sustainability index(ESI) of maize, wheat, rice and soybean systems were increasing during 2000–2015, and the CF on unit yield of the crops had been reduced by 10-30% in the study period. The results reflected the improved environmental sustainability of grain system in China during 2000–2015. Nevertheless, the emergy flow of industrial inputs for the crops were increased by 4-22% in the study period, and the CF from the inputs presented a growth rate of 16-23% as well during the same period. The results implied that the grain system in China was relying more on fossil-based inputs. Finally, according to the key points of cost, emergy and CF, we suggest that improving labor efficiency, advanced agricultural practices and optimizing cropping pattern will be effective ways to further improve the economic and environmental sustainability of grain system in China.     

杂种蓝莓(野生ב美登’)组培快繁

为了建立高效的杂种蓝莓组培快繁技术体系,以大兴安岭地区野生蓝莓和栽培品种‘美登’(‘Blomidon’)杂交获得的杂交种子为试材,筛选出杂交种子最佳无菌处理条件,获得蓝莓杂种无菌苗。再以杂种无菌苗茎段为外植体,探究了不同质量浓度植物生长调节剂(ZT)、蔗糖及继代周期对丛生芽诱导的影响,并探讨了培养基种类及植物生长调节剂IBA质量浓度对生根诱导的影响。结果表明:杂交种子经75%酒精和3%次氯酸钠分别处理20 s和7 min效果最好,污染率为0;添加0.6 mg·L~(-1)ZT和20 g·L~(-1)蔗糖的WPM培养基为丛生芽诱导最佳培养基,诱导率高达100%,且芽丛密集、长势好;芽诱导期间,30 d的继代周期最有利于丛生芽的增殖,增殖倍数高达34.72;最佳生根培养基为添加0.4 mg·L~(-1)IBA的1/2WPM培养基,生根率高达88%,且生根周期仅为40 d,移栽成活率达到85%以上。     

中山杉(Taxodium‘Zhongshansa 302’)扦插繁殖育苗试验

为了探索解决江苏沿海防护林、用材林和城镇、公路、渠堤绿化林树种单一问题的途径，进行了中山杉（Taxodium‘Zhongshansa302’）扦插繁殖育苗试验。选择抗逆性强、性状优良的中山杉302树种的1～2年生枝条，利用草木灰＋菜园土为扦插基质，0．5mg／1NAA＋0．5mg／1IAA为生根促进剂，通过“三重保温”育苗技术，扦插生根率达67％以上，平均苗高为50．3cm左右。结果表明，该树种的扦插育苗在盐城这样的生境中是可行的。     

Development and optimization of a double antibody sandwich ELISA for the detection of goose T cell surface CD8α molecule

CD8, a glycoprotein on the surface of T cells, is involved in the defense against viral infection and plays significant roles in antigen presentation and in the antiviral immune response. CD8 is composed of two chains. Of these, the CD8α chain was chosen for the detection because it involved in both the CD8αα homodimer and the CD8αβ heterodimer. Here, we established a double antibody sandwich enzyme-linked immunosorbent assay(DAS-ELISA) for specific detection of goose CD8α(go CD8α). The results showed that the optimal coated antibody and antigen dilutions were 1:50(the antibody titer was 1:12 800) and 1:32(0.3 ng m L~(–1)), respectively, while the optimal capture antibody and horseradish peroxidase(HRP)-labelled goat anti-rabbit Ig G dilutions were 1:50(the antibody titer was 1:51 200) and 1:4 000(the antibody titer was 1:5 000), respectively. The optimal blocking buffer was 5% bovine serum albumin(BSA). The best incubating condition was overnight at 4°C, the best blocking time was 120 min and the best anti-capture antibody working time was 150 min. In addition, the minimum dose detectable by DAS-ELISA was 5×10~(–3) ng m L~(–1). Most importantly, go CD8α expression levels in goose spleen mononuclear cells(MNCs) post-Goose parvoviruse(GPV) infection were found to be significantly up-regulated using the DAS-ELISA method, which was consistent with previous results obtained using real-time quantitative PCR. In conclusion, the DAS-ELISA method reported here is a novel, specific technique for the clinical detection of go CD8α.     

Forecasting Fruit Diameter of ‘Fuji’Apples (Malus pumila Mill )at Harvest During Early Growing Season

The fruit growth evolution on 35 tagged‘Fuji‘apple trees was studied in three successive growing seasons from 1994 to 1996 to explore a new method for forecasting the fruit diameter at harvest during early growing season. Daily fruit growth rate (DFGR) (based on fruit diameter, fruit dry weight, fruit fresh weight, or fruit volume) during the early growing season, 30 - 50 d after full bloom (DAFB), or during midgrowing season (60 - 120 DAFB), displayed a strong positive linear correlation with the fruit diameter at harvest, and the correlation between the fruit diameter at harvest and DFGR during early and mid-growing season was much better than that between the fruit diameter at harvest and either fruit diameter at a given time or the relative growth rate during early or mid-growing season. The fruit diameters obtained in the field were compared with the mean fruit diameters estimated based on different criteria, such as DFGRs (based on fruit diameter, fruit dry weight, fruit fresh weight, or fruit volume) during early and mid-growing season, and fruit diameter at 120 DAFB. Results showed that daily growth rate of fruit diameter during 30 - 50 DAFB was the best criterion for forecasting fruit diameter at harvest. There was no significant difference in mean fruit diameter between the value measured in the field at harvest and that estimated based on the daily growth rate of fruit diameter during 30 - 50 DAFB (equations for forecasting: y = 153. 571 x + 73. 492) either for the individual trees or for different vigor groups of trees. Daily growth rate of fruit diameter during 30 - 50 DAFB can be used as the basis for forecasting fruit diameter at harvest.