Alternative cropping systems can have contrasting effects on various soil-borne diseases: Relevance of a systemic analysis in vegetable cropping systems

Vegetable production makes an intensive use of pesticides, and a major challenge is to build alternative cropping systems that can control pests and diseases with fewer uses of chemical products. An on-farm analysis was conducted in Southeast France to assess the efficacy of several cropping systems in simultaneously controlling two major pests: root-knot nematodes (Meloidogyne spp.) and lettuce drop due to Sclerotinia sclerotiorum. Ten cropping systems resulting from the combinations of three crop sequences and two alternative techniques, solarization and green manure, were assessed during two years. The use of solarization once a year or once every two years limited the occurrence of S. sclerotiorum. Sorghum green manure tended to increase S. sclerotiorum incidence; the effect was positively correlated with green manure duration. Especially when no vegetable was cropped in summer, the green manure crop duration was lengthened and this probably created soil conditions favorable to the development of the fungus. The incidence of root-knot nematodes was largely dependent on crop rotation: a melon crop in summer increased its incidence on the subsequent lettuce crops whereas a summer sorghum cover crop had no effect. The cropping systems that limited Sclerotinia development in soil tended to support the root-knot nematode populations. These results should motivate farmers and advisers to adopt a systemic analysis and take into account the various interactions among inoculum level, soil characteristics, crop rotations, and technical management options for designing sustainable vegetable production systems.     

姜堰区扶持粮食生产的措施及发展对策

介绍了姜堰区扶持粮食生产的相关政策,分析了姜堰区粮食生产基本情况,总结了取得的成绩,阐述了姜堰区政府扶持粮食生产采取的措施和做法,并对存在的问题提出相应建议。     

DIVECOSYS: Bringing together researchers to design ecologically-based pest management for small-scale farming systems in West Africa

Crop pests are a major constraint to the intensification of agricultural production in the tropics, with novel issues related to global change (climate, land use, biological invasions, etc.), food security and preservation of natural resources and biodiversity. A research, extension and education network called DIVECOSYS (Diversity of cropping systems and ecologically-based pest management in West Africa) was launched in 2010 to synergize applied research actions in response to growing concerns on the vulnerability of agricultural systems to pest management in West Africa. This scientific network brings together research and academic institutions, with expertise spanning a multidisciplinary perspective from biology and ecology to remote sensing, agronomy and integrated pest management. Its main scientific objective is to explore the potential of biodiversity and ecological processes such as pest regulation, enabling novel ecologically-based models for productive systems, reduction of pesticide use, and adaptation or resilience of farming systems in the face of environmental disruptions. From Northern Senegal to Southern Benin, the research group explores a wide range of ecoregions and socio-ecological contexts, including stakeholders and their objectives, land use and agricultural practices, and management of biodiversity for enhancing biological control. Main challenges to be turned into opportunities include (i) encouraging collaborations amongst researchers from different scientific fields, (ii) fostering interactive research and synergies among research institutions and among countries, and (iii) developing an ecological engineering approach for the design of sustainable agricultural systems for smallholder farmers.     

Trends and approaches in the analysis of ecosystem services provided by grazing systems: A review

The ecosystem services (ES) approach is a framework for describing the benefits of nature to human well‐being, and this has become a popular instrument for assessment and evaluation of ecosystems and their functions. Grazing lands can provide a wide array of ES that depend on their management practices and intensity. This article reviews the trends and approaches used in the analysis of some relevant ES provided by grazing systems, in line with the framework principles of the Millennium Ecosystem Assessment (MA). The scientific literature provides reports of many studies on ES in general, but the search here focused on grazing systems, which returned only sixty‐two papers. This review of published papers highlights that: (i) in some papers, the concept of ES as defined by the MA is misunderstood (e.g., lack of anthropocentric vision); (ii) 34% of the papers dealt only with one ES, which neglects the need for the multisectoral approach suggested by the MA; (iii) few papers included stakeholder involvement to improve local decision‐making processes; (iv) cultural ES have been poorly studied despite being considered the most relevant for local and general stakeholders; and (v) stakeholder awareness of well‐being as provided by ES in grazing systems can foster both agri‐environmental schemes and the willingness to pay for these services.     

海南省支农财政支出与经济增长的相关性研究

在简要论述海南省财政支出结构的基础上,分析了财政支出结构与经济增长的相关关系,得出海南省的财政支出中用于支持农业生产的资金利用效率最高,对海南经济的贡献率最大,进而提出了一系列支持海南农业发展的措施。     

基于生长发育天数的稻鸭生态种养专家系统框架设计

在总结稻鸭生态种养经验的基础上,采用人工智能技术,提出了基于生长发育天数的稻鸭生态种养专家系统的设计方案,分析了稻鸭生态种养专家系统的框架设计、知识的获取和模块的内容、数据库结构设计.     

兴建茶树良种繁育示范场的实践与体会

2000年由农业部投资,浙江开始在新昌县大市聚镇兴建国家级茶树良种繁育示范场.经过3年建设,示范场已初具规模,现有茶园面积1000亩,其中采穗园700亩、良种繁育苗圃200亩、种质资源圃20亩、设施茶园20亩、品种园60亩,年可提供无性系良种插穗40万kg ,无性系良种茶苗2000万株.     

Endoscopic findings and Helicobacter pylori in children on long-term hemodialysis

The aim of this study is to evaluate the prevalence of GI symptoms, endoscopic abnormalities, histologic gastritis and Helicobacter pylori infection in children with End Stage Renal Disease (ESRD) undergoing maintenance hemodialysis. Upper endoscopy and gastric biopsy were performed in 31 consecutive ESRD children from 2002-2007, before renal transplantation. H. pylori status was determined by urease test and histology. The mean age of patients was 11 +/- 3.3 years (4-16 year). The mean duration of dialysis was 12.4 +/- 11 months (1.5-54 months). Seventeen patients (54.8%) were symptomatic. Twenty patients (64.5%) had endoscopic abnormalities. Antral erythema, esophagitis, antral nodularity and diffuse gastritis were common endoscopic findings. Endoscopic abnormalities were more common in symptomatic patients than asymptomatic patients (p < 0.05). Twenty patients (64.5%) were H. pylori positive. There was no statistical correlation between age, sex, serum creatinine level, presence of any symptoms and endoscopic abnormalities with H. pylori positivity. The mean duration of dialysis in H. pylori negative patients was significantly longer in comparison with H. pylori positive patients. High prevalence of eodoscopic abnormalities and H. pylori infection in both symptomatic and asymptomatic patients emphasize the necessity of upper GI evaluation in ESRD children before renal transplantation.     

Multivariate analysis of ToF-SIMS data from multicomponent systems: the why, when, and how

The use of multivariate analysis (MVA) methods in the processing of time-of-flight secondary ion mass spectrometry (ToF-SIMS) data has become increasingly more common. MVA presents a powerful set of tools to aid the user in processing data from complex, multicomponent surfaces such as biological materials and biosensors. When properly used, MVA can help the user identify the major sources of differences within a sample or between samples, determine where certain compounds exist on a sample, or verify the presence of compounds that have been engineered into the surface. Of all the MVA methods, principal component analysis (PCA) is the most commonly used and forms an excellent starting point for the application of many of the other methods employed to process ToF-SIMS data. Herein we discuss the application of PCA and other MVA methods to multicomponent ToF-SIMS data and provide guidelines on their application and use.     

Recent findings on certain bioactive components in whole grain wheat and rye

Whole grain wheat and rye are important sources of many bioactive compounds and contribute significantly to the total intake of cereals in many countries. Alkylresorcinols, benzoxazinoids, lignans, phenolic acids, phytosterols and tocols are common bioactive compounds present in these cereals. In this review, we report recent findings (mainly from 2010 onwards) regarding their content, composition, effects of food processing and their uptake, elimination and bioactivities with implications for health.     

Multifunctionality and non-trade concerns: implications for future agricultural policy in Asia

Agriculture's multifunctional role as provider of non-commodity outputs has received increased attention in the debate on the future of agricultural policy. To identify appropriate economic policies, a distinction must be made between concerns involving market failure and a consequent misallocation of resources, and those relating to distributional issues. We argue that it is essential to restrict the concept of multifunctionality to non-commodity outputs involving technical externalities or public goods and for which market failure and the misallocation of resources are important (e.g., amenity values and agricultural pollution). Other non-trade concerns, such as rural incomes and employment and food security, involve distributional issues, but no resource misallocation. This distinction makes it possible to identify different types of domestic policy measures to address them effectively and efficiently. Through reference to an empirical application to Taiwanese paddy rice policy, we illustrate that the most effective way to reconcile non-trade concerns is through policy measures that correct for market failure by valuing non-commodity outputs appropriately and a separate set of measures that address distributional issues.

Soil fertility management in irrigated rice systems in the Sahel and Savanna regions of West Africa: Part I. Agronomic analysis

Yield, input use, productivity and profitability of irrigated rice systems were analyzed based on surveys in Senegal (Thiagar and Guédé), Mali (Office du Niger) and Burkina Faso (Kou Valley). The objective was to determine agronomic factors contributing to farmers' fertilizer-use efficiency and productivity, given current farmer practices. (A second paper addresses profitability and risk issues). Grain yields were highly variable, within and across sites. Minimum grain yield was 0.2 t ha⁻¹ (Thiagar), maximum recorded grain yield was 8.7 t ha⁻¹ (Office du Niger). The yield gap between actual farmers' yield and simulated potential or maximum attainable farmers' yield ranged from 0.6 to 5.7 t ha⁻¹ (Kou), 1.8 to 8.2 t ha⁻¹ (Thiagar), 0.3 to 6.3 t ha⁻¹ (Office du Niger), 0.8 to 5.7 t ha⁻¹ (Guédé), indicating considerable scope for improved yield. Physiological nitrogen efficiency (δ grain yield/δ N uptake) was mostly between 40 and 80 kg grain kg⁻¹ plant N. Apparent recovery of fertilizer N was highly variable (average: 30–40% of applied N). Timing of N fertilizer application by farmers was extremely variable and often did not coincide with critical growth stages of the rice plant. Other agronomic constraints included: use of relatively old (>40 days) seedlings at transplanting (Kou, Office du Niger), P and/or K deficiency (Office du Niger), unreliable irrigation water supply (Kou, dry season), delayed start of the wet growing season resulting in yield losses of up to 20% due to cold-induced spikelet sterility (Kou, Guédé, Office du Niger), weed problems (Thiagar), and late harvesting (Thiagar). Discussions during meetings with farmers at the survey sites revealed that farmers lacked knowledge on (i) optimal timing, dosage and mode of fertilizer application, (ii) optimal sowing dates to avoid yield loss due to cold- or heat-induced sterility, and (iii) the importance of N as the main limiting factor to yield. Possibilities to achieve a sustainable increase in rice productivity and profitability in West African irrigation systems are discussed.     

Soil fertility management in irrigated rice systems in the Sahel and Savanna regions of West Africa: Part II. Profitability and risk analysis

In irrigated rice production in West Africa, nitrogen (N) and phosphorus (P) fertilizers make up about 20% of total production costs. This research seeks to evaluate whether those fertilizers are profitable under current use by farmers and to identify the factors that may improve fertilizer efficiency and profitability. A combination of farmer surveys and on-farm trials were used to determine actual fertilizer use, costs, and net revenues from fertilizer in key irrigated systems in Mali (Office du Niger), Burkina Faso (Kou Valley), and Senegal (Thiagar and Guédé). A second paper provides an agronomic analysis of soil fertility management at these sites. Net returns to fertilizer use were estimated and value/cost ratios (VCRs) calculated. A value/cost ratio of 1.5–2.0 was considered desirable for farmer adoption under West African conditions. Average VCRs for fertilizers ranged from 1.6 in the Kou Valley in Burkina Faso, to 3.6 in the Office du Niger, Mali. In researcher-managed on-farm trials in Thiagar, Senegal, fertilizers had VCRs of 1.5–3.1. Large N doses of 180 kg N ha⁻¹ still had VCRs of 2.5. Farmers in the region used less than recommended doses of N, with the exception of farmers in the Office du Niger, Mali. With an average application of 89 kg N ha⁻¹, farmers in Thiagar, Senegal were able to gain 54 000 FCFA ha⁻¹ (US$ 110) of net revenues from the fertilizers with fertilizer N recovery rates averaging 34%. Improving that recovery rate by 50% could increase net revenues by 50%. In field trials in Thiagar, increasing N application to 180 kg ha⁻¹ resulted in net returns of near 200 000 FCFA ha⁻¹ for an investment of 118 000 FCFA ha⁻¹. Risk of negative net returns was found in Thiagar and in Kou Valley, and was related to weed infestation and water scarcity, respectively. Farmers in the dry season in Kou Valley had a 33% probability of net losses with fertilizer application because of unreliable water supply. In contrast, no farmers had negative returns in the Office du Niger inspite of high N application rates. Farmers can improve profitability and economic efficiency in irrigated rice production in two ways. First, they can modify crop management practices (date of seeding, date and mode of fertilizer application, etc.) in order to improve the recovery rate of applied N, thus relaxing the nitrogen fertilizer constraint. Second, for farmers able to purchase additional fertilizer, there are gains to be made by increasing applied nitrogen at least to recommended levels in most areas. Credit allocations that restrict fertilizer purchases are counterproductive given the profitability of fertilizers. Negative returns were found only in areas with high risks of water scarcity or weed infestation. Researchers and development agents need to develop more site-specific fertilizer recommendations that correspond to weather, cultivars, prices of inputs and outputs, and fertilizer products.     

Delignification of Eucalyptus globulus saplings in two organosolv systems (formic and acetic acid): Preliminary analysis of dissolved lignins

Organosolv delignification of 2–3 years old Eucalyptus globulus with formic or acetic acid produced bleachable grade pulps with kappa number values of 20–35. Pulp yields for the acetic acid treatment (45–55%) were higher than for formic acid (32–46%) although also they showed the greater kappa number.Delignification was modelized by means of the accomplishment of respective factorial designs of experiments. Data were successfully fitted by mathematical models for prediction of pulp yield and kappa numbers from the process variables.Recuperation of the dissolved lignin, by means of water precipitation, allowed the recovery of about a 20% of the initial raw material (about 80% of lignin).Chemical and spectroscopic analyses for the determination of the contents of main functional groups in lignin were made and C9 formulae calculated, as follows: C₉H_7.58O_2.34(OCH₃)_0.80(COOH)_0.18(OH_Ar)_0.35(OH_R)_0.58 and C₉H_6.14O_1.55(OCH₃)_1.09(COOH)_0.18(OH_Ar)_0.52(OH_R)_0.58 for the products obtained with formic acid and acetic acid, respectively.     

Regrowth dynamics and grazing decision rules: further analysis for dairy production systems based on perennial ryegrass (Lolium perenne L.) pastures

To support the further development of grazing practices for dairy production systems based on perennial ryegrass (Lolium perenne L.), allometric relationships among leaf‐stage categories and pseudostem were derived for perennial ryegrass tillers sampled from swards each month, from July 2008 to January 2010, within a dairy grazing‐system experiment in south‐west Victoria, Australia. The relative lamina mass of the first leaf that emerged on tillers following grazing (denoted L3) and the subsequent leaf to emerge (L2) was used as an indicator of the trajectory of regrowth. L2 was consistently 30–40% heavier than L3 during the period July–September (mid‐winter to early spring), but thereafter the difference between leaf stages lessened, and disappeared altogether in late spring. No substantial lag was observed in the rate of herbage accumulation during the early stages of regrowth of perennial ryegrass swards from 1500 kg DM ha^?1 post‐grazing. Therefore, grazing at any time in the period between emergence of the second and third leaves after the previous defoliation event should lead to high efficiency of pasture harvest under most conditions. The dry‐matter digestibility (DMD) and crude protein (CP) content of the most recently emerged leaf (denoted L1) declined sharply during spring, whereas the DMD and CP content of older leaves were more consistent. Decision rules for grazing management should include sufficient flexibility to account for interactions between leaf stage and time of year in relative lamina mass and nutritive value.     

Potassium cycling and losses in grassland systems: a review

Cycling of potassium in grassland systems has received relatively little attention in research and practice in recent years. Balanced nutrient systems require consideration of nutrients other than nitrogen (N). Potassium (K) is needed in large amounts and is closely related to N nutrition. In intensive dairy farming, surpluses of K arise from the input of concentrates and fertilizer and are returned to the grassland and may lead to increasing K content in the soil. Organic farming, on the other hand, is characterized by limitations in input of nutrient sources and quantities. Leaching of K from grassland is usually low, but high levels of available soil K, high K input from fertilizer or at urine patches lead to increasing losses. High K inputs have a negative influence on Mg and Ca uptake by plants and can cause accelerated leaching of these cations. High levels of K have been associated with inducing nutrition‐related dairy cow health problems such as milk fever (hypocalcaemia) and grass tetany (hypomagnesaemia). This review gives an overview of the cycling of potassium and related cations in grassland systems especially with regard to leaching losses and identifies limitations to knowledge.     

茶叶抗癌的效果：过去、现在和将来

癌症是对人类最具威胁和死亡率最高的一种疾病。据报告,目前全世界每年因癌症而死亡的人数为700万人。30年来,世界各国在癌症研究上取得了很大的进展,但在最关键的治疗方法上还没能取得令人鼓舞的结果。其关键问题是治疗癌症的药物可以杀死人体中的癌细胞,但这种浓度与对人体正常细胞的致死浓度非常接近,     

Silage and total mixed ration hygienic quality on commercial farms: implications for animal production

Implications of silage hygienic quality for animal production were investigated on forty‐five dairy farms in South West England. Samples of grass and maize silages and of total mixed rations (TMR) were obtained together with information on silage technology, herd size and animal production. Samples were analysed for mycotoxins, bacteria, yeasts, moulds and chemical composition. Thirteen mycotoxins were assayed, but none were detected in the samples of grass silage. However, mycotoxins were found in 0·9 of all maize and other silage samples, with deoxynivalenol and zearalenone predominating. There was no relationship between total mycotoxin concentration and mean lactation milk yield per cow. Enterobacteria counts tended to be higher in maize silage than in grass silage and higher still in TMR – a cause for concern. There were no relationships between mould counts and mycotoxin concentrations in silages, implying that mycotoxins may have been produced in the field pre‐ensiling.     

Impact of different baking processes on bread firmness and starch properties in breadcrumb

The influence the quality and shelf life of baked product has previously been reported to be effected by the time and temperature of the baking process. In this study, dough was baked at 219 °C by using different ovens (conventional, impingement or hybrid) or with doughs of different sizes (large or small) for varying times. During baking the temperature profile at the dough center was recorded. Texture, thermal properties and pasting characteristics of baked product with reference to baking conditions were investigated. Small breads baked in the hybrid oven had the highest heating rate (25.1 °C/min) while large breads baked in conventional oven had the lowest heating rate (6.0 °C/min). When the data are viewed as a function of heating rate in this study, the enthalpy of amylopectin recrystallization, rate of bread firmness and the amount of soluble amylose were all-lower at the slower heating rate. The differences observed in product firmness following storage are potentially a consequence of the extent of starch granule hydration, swelling, dispersion and extent of reassociation; all of which are affected by the heating rate during baking.