Assessing Sources of Information for Urban Mushroom Growers in Accra,Ghana

This study assessed information sources for urban mushroom farmers in Accra, Ghana. One hundred farmers were sampled, and a structured questionnaire was administered to solicit information from the respondents. Results showed that the majority of farmers were male (71%) and most (60%) with university education. The majority (44%) had 1–5 years of experience in mushroom cultivation. Co-farmers (89.8%), the Mushroom Growers Association (79.6%), training workshops (73.5%), and the Farmers' Forum (29.6%) readily served as information sources for farmers. The research revealed that, for 52% of farmers, ignorance of information sources was a major hindrance in their quest for information.     

喜玛拉雅地区山地旱冬瓜轮歇与问作系统研究

种植在农地上的旱冬瓜能促进农作物生长,据测定1t旱冬瓜树叶干物质量的肥力相当于14.3kg硫酸铵、2.4kg过磷酸钙和2.2kg硫酸钾,农户习惯以鲜叶6000～7500kg/hm~2替代1.5万kg/hm~2水稻种植的有机圈肥,并分析了喜玛拉雅地区印度东北部和中国云南省以旱冬瓜为基础的混农林轮作丢荒管理系统。     

玉米豆科覆盖作物间作对潮土酶活性和真菌群落特征的影响

黄淮海地区土地复种指数高，不具备休闲条件，致使土壤养分消耗严重，土壤微生物群落多样性下降。为改善土壤状况，本研究基于两年的玉米豆科覆盖作物（紫花苜蓿、大豆、花生）间作试验，探讨玉米豆科覆盖作物间作对土壤养分、酶活性以及真菌群落特征的影响，同时分析黄淮海平原潮土区玉米豆科覆盖作物间作的可行性。结果表明：间作条件下土壤碱解氮含量提高，土壤有机质含量无明显变化，玉米紫花苜蓿间作处理和玉米花生间作处理土壤有效磷含量表现上升趋势。所有间作处理土壤脲酶活性都高于单作玉米处理，间作花生处理和间作大豆处理的酸性磷酸酶活性较单作玉米处理分别增加了30.53%和18.70%；间作紫花苜蓿处理土壤碱性蛋白酶活性和蔗糖酶活性对比单作玉米处理有显著提高。间作紫花苜蓿处理和间作大豆处理对土壤优势菌门子囊菌门和被孢霉门的相对丰度有积极作用，其中间作紫花苜蓿处理子囊菌门的相对丰度提高了11.88%，间作大豆处理被孢霉门相对丰度增幅达45.39%，优势菌门丰度的提升有助于补充土壤氮源和碳源。玉米豆科覆盖作物间作可以补充土壤养分，改善土壤微生物群落结构，提高土壤酶活性，可能成为提高黄淮海平原潮土地区土壤质量、维持土壤稳定性的有效措施。     

间套作改善作物矿质营养的机理研究进展

【目的】合理的间套作能够改善作物的矿质营养。近年来国内外对间套作提高作物生产力、 改善作物矿质营养的机理研究越来越深入。本文分析了国内外不同间套作中作物根际养分动态及作物营养吸收变化,阐述了间套作改善作物矿质营养的可能机理。【主要进展】 1)根系分泌物中的铵态氮和氨基酸态氮作为作物的氮源; 根系分泌物能够诱导豆科作物固氮作用的增强,增加间套作系统中的氮营养; 2)根系分泌物中的有机酸类物质能够活化根际土壤中的磷、 铁、 钾等营养,将其转变为植物可以利用的营养; 3)根系分泌物或地上部的种间互作能诱导作物的根系构型和矿质营养吸收相关基因的表达发生变化,形成空间上的营养生态位互补,增强根系吸收矿质营养的能力,充分利用土壤营养资源; 4)丛枝菌根真菌与作物间形成的网络便于营养在作物之间的转移和吸收; 5)间套作能够改变土壤生物多样性(土壤动物和微生物),而土壤的生物多样性能够促进作物矿质养分的吸收。间套作中,由于微生物代谢功能的多样性,作物对微生物的选择和富集使得根际土壤功能微生物的种类和数量增多,提高了土壤中矿质营养的生物有效性; 6)间套作提高了土壤的酶(如脲酶,酸性磷酸酶和碱性磷酸酶)活性,促进了有机氮、 磷向无机氮、 磷的转化,提高了土壤无机氮、 磷的浓度。总之,根系分泌物、 根系构型变化、 土壤生物多样性、 土壤酶在作物的营养有效利用中发挥重要作用,其中根系分泌物是它们之间的纽带,介导了作物-作物、 作物-土壤、 作物-微生物之间的相互作用。【建议与展望】由于技术手段的限制及地下根际过程的复杂性,人们对于地下生物学过程的认识还远远不够。根系分泌物的原位定性与定量、 间套作中种间的识别和响应、 间套作对土壤生物多样性的影响及土壤生物多样性对作物生长的反馈、 间套作中功能微生物的筛选、 分离、 鉴定及应用都将成为研究的重点。     

重金属污染土壤间作修复的研究进展

种植单一的超富集植物修复重金属污染土壤,不但中断农业生产导致经济收益降低,而且因生物量较低、修复周期长等诸多弊端导致修复效果不甚理想。间作作为一种传统的农艺管理方式,利用生态位和生物多样性原理等能提高农作物对资源的有效利用,对共植的农作物种类增量提质。在中、轻度污染土壤修复中利用间作体系,通过调控超富集植物与农作物的生长发育,促进超富集植物根系低分子量有机酸(LMWOAs)的分泌,降低其根际土壤p H,增加重金属活性,从而增加超富集植物对重金属的吸收,同时抑制农作物根系LMWOAs的分泌,以减少农作物对重金属的吸收,提高其产量和品质,实现"边生产边修复",提高土地利用率,并增加经济效益。本文根据近几年来国内外相关文献,综述了间作条件下超富集植物和农作物生物量、生理生化响应、重金属吸收、转运、富集等方面的变化,以及间作对土壤环境质量的影响,并对间作修复重金属污染土壤领域的发展趋势,如超富集植物和农作物间作的信号转导和分子生物学机制、间作体系下两类植物根际微生物类群的差异及其功能机制,以及构建高效间作体系提高重金属污染土壤的修复效率等方面进行了展望。     

春小麦与玉米、向日葵间作套种对土壤水分的影响

在河套灌区以春小麦、玉米、向日葵单作为对照,测定并分析了春小麦/玉米、春小麦/向日葵间作套种作物生长季0—120cm土层土壤水分及作物产量。结果表明,春小麦/玉米、春小麦/向日葵间作套种生长季的土壤水分蒸散强度为双峰曲线,春小麦、玉米、向日葵单作为单峰曲线。春小麦/玉米、春小麦/向日葵间作套种的土壤水分蒸散量高于春小麦、玉米、向日葵单作。春小麦/玉米、春小麦/向日葵间作套种提高了作物产量,提高了土地当量比,但降低了作物生长期、作物生长季及灌溉水的水分利用效率和水分当量比。建议河套灌区减少间作套种面积,或间作套种时在不同作物之间修建土埂隔挡,根据不同作物对水分的需求分别灌溉。     

台湾有机农业的现况

有机农业之定义宽严界定因人而异,自完全自然放任的生态平衡农业耕作方式至不施用化学肥料及农业药剂或有限使用化学肥料与农业药剂的农耕方式。主要在倡导自然界物质之循环利用,维护生态,节省能源,减少污染,土地之永续利用,生产安全健康的农产品。可与宗教、生态保护、农药受害、地力维持、祈求安全食品者相结合发展。基于此种观点,在省中、南部设置相关试区,测试有机农法理念在台湾地区进行之可能性,包括利用轮作,间作,生物防治及微生物肥料于耕作中。综合目前试验成果显示,有机农耕法作物产量渐与惯行法相近,或略为增产。产品风味佳但     

有关间混作研究中几个问题的探讨

本文从间混作系统的整体出发，运用生态学原理论述了间混作研究中密度、施肥量、两种作物之间的比例关系、产量的表示方法和总产的计算问题，并运用粗密度、生态密度和标准化产量概念阐明了间混作实占面积与整体面积产量以及总产的计算问题，将行比与作物比有机地结合在一起，从而能够更加完整地反映出间混作的空间排列和群体大小。     

Analysis of Market Information Sources for Agricultural Transformation Among Cassava Farmers in Moro Local Government Area of Kwara State,Nigeria

This study investigated sources of market information among cassava farmers in Kwara State, Nigeria. A multistage random sampling technique was employed; data were collected through an interview schedule and described and analyzed using frequency counts, percentages, and chi-square. Results showed that the majority of the cassava farmers were male and married, had no formal education, and sourced market information from middlemen. There was a significant relationship between respondents’ personal characteristics, such as tribe and primary occupation (χ² = 34.360, χ² = 43.203), and market information sources. Market information should be disseminated using local languages preferred by cassava farmers and be reliable, timely, and relevant.     

棉花间作模式中作物养分竞争吸收和积累动态的研究

本研究通过田间试验研究了棉花和豆科作物、蔬菜作物间作后种间相互作用对氮磷钾等养分积累动态的影响,旨在为新疆棉花为主的间作体系的发展提供科学依据.试验设置花生、大豆、鹰嘴豆、洋葱、萝卜、线辣椒与棉花间作及相应各个作物单作的田间试验,分析了间作作物氮磷钾养分吸收的积累动态相对于单作作物的变化.结果表明,棉花和大豆以及棉花和萝卜共生期间,棉花对养分的竞争能力(CRcc1)弱于大豆和萝卜(CRcc1 ＜1),表现为大豆和萝卜生长及养分吸收积累处于优势地位,棉花处于不利地位;棉花和辣椒、花生、洋葱共生期间,棉花对养分的竞争能力强于辣椒(CRcc1＞1),表现为棉花生长和养分吸收积累处于优势地位,辣椒、花生、洋葱处于不利地位;棉花和鹰嘴豆共生的前一阶段,棉花对的养分竞争能力弱于鹰嘴豆(CRcc1＜1),但到鹰嘴豆收获前,棉花对养分的竞争能力则强于鹰嘴豆(CRcc1＞1),表现为棉花生长处于优势地位,鹰嘴豆处于不利地位.棉花/花生、棉花/洋葱、棉花/辣椒和棉花/萝卜间作体系具有明显的间作优势,并且对棉花产量没有不利影响,适合当地生产应用.     

An Assessment of the Contribution of Urban Crop Agriculture in Nigerian Cities: A Case Study of Enugu Metropolis,Enugu State,Nigeria

This study examined the contribution of urban crop agriculture in Enugu metropolis, Enugu State. A questionnaire/interview schedule was used to collect information from 60 urban agriculture (UA) farmers. Respondents were engaged in UA to provide food for family members (97%), for extra income (91.67%), and to pay children's school fees (85.45%). The average amount realized from sales of UA produce was US$11 per week. The destruction of crops by stray animals, theft, and lack of information were identified as the major barriers to UA in the study area. Only 20% of the respondents were aware of extension services. Urban agriculture as practiced today in Enugu is of limited scale. To reach its full potential, government intervention is needed.     

覆盖作物－玉米间作对土壤碳氮含量及相关酶活性的影响

  目的  针对东北地区常规农业重用轻养以及玉米连作导致土壤养分不均衡、土壤健康下降等问题,开展覆盖作物－玉米间作对土壤碳氮含量及相关酶活性的影响研究,以期为东北地区保护性利用模式的扩展提供科学依据。  方法  在覆盖作物－玉米间作种植模式下,探讨紫花苜蓿、毛苕子和黑麦草三种覆盖作物对土壤碳氮及酶活性的影响。  结果  不同种植模式和覆盖作物类型显著影响了覆盖作物－玉米间作系统的土壤氮含量及相关酶活性,土壤有机碳含量仅在不同种植模式间有显著差异。在拔节期,与玉米单作相比,紫花苜蓿－玉米间作可以显著增加土壤速效氮含量,其硝态氮和铵态氮含量分别增加了14.94 mg kg?1和2.07 mg kg?1,并且参与氮转化的亮氨酸氨基肽酶活性提高17.9 nmol g?1 h?1。与其他覆盖作物相比,单作毛苕子可以显著提高土壤乙酰氨基葡萄糖苷酶和亮氨酸氨基肽酶的活性。毛苕子间作系统的过氧化氢酶和多酚氧化酶活性显著高于黑麦草间作系统,二者分别提高了12.65%和66.94%。在成熟期,玉米单作和间作的土壤有机碳和全氮含量显著高于覆盖作物单作,土壤碳氮水解酶和氧化酶活性均无显著差异。冗余分析表明,土壤铵态氮含量是影响土壤酶活性的关键环境因子。  结论  玉米与豆科覆盖作物的种植增加了间作玉米土壤速效氮的含量,提高了氮转化相关酶的活性,增强了土壤氮素转化潜能及可利用性。研究区适宜选取紫花苜蓿和毛苕子作为覆盖作物种植。     

Agricultural Information Needs of Root and Tuber Farmers in the Atisbo Local Government Area of Oyo State,Nigeria

This study assessed the agricultural information needs of root- and tuber-crop farmers in the Atisbo Local Government Area of Oyo State. A simple random sampling technique was used to select respondents. Data were presented using percentages and rankings. The most utilized sources of information on agricultural practices were associations (75.8%), other farmers (70.8%), and extension agents (60.8%). Agricultural information reported as “highly needed” by respondents included marketing procedures, processing and improved planting techniques, and soil management methods. Chi-square test results showed a significant relationship between selected personal characteristics of respondents (gender χ² = 24.9, p < .05; educational status χ² = 10.8, p < .05; marital status χ² = 181.1, p < .05 and household size χ² = 48.6; p < .05) and information needs.     

Dynamics of Agricultural Information and Effect on Income of Melon Farmers in Enugu-Ezike Agricultural Zone of Enugu State,Nigeria

ABSTRACT

The study assessed effects of agricultural information on the income of melon farmers. Ninety melon farmers constituted the sample for the study. Data were collected through an interview average annual income of the respondents from melon only was ?7,455.4, while their total average schedule, while percentage mean score and correlation were used in the analysis. Findings reveal that the monthly income was ?1,223. About 62 and 42% of the respondents, respectively, did not receive information on melon production and general agriculture. Thus, a positive and significant relationship exists between the number of times respondents received information on melon/general agriculture and their incomes.     

玉米花生间作播种施肥一体机研制与试验

针对玉米花生间作播种经济效益高但缺少一体化作业机械装备的现实问题,采用农机农艺融合的研究方法,开发了1种1次作业可以实现旋耕筑垄、混土施肥、玉米花生间作播种和对行覆土镇压等功能的玉米花生间作播种施肥一体机,并对影响垄台筑建、沟床平整的旋耕装置和最小结构尺寸的平行四杆机构进行了设计;采用正交试验方法探究了旋耕刀轴转速、耕深和仿形机构拉杆长度对花生垄台高度和播深一致的影响规律,结果表明:在旋耕刀轴转速为260r/min,耕深15cm及仿形机构拉杆长度为24cm时,即可为玉米花生间作创造良好的播种环境,且花生播深合格率达91.1%,玉米播深合格率达90.1%,其他参数完全符合相关农艺标准,为该农艺技术的推广应用提供可供选择的机械化装备.     

谷子播期对谷子/花生间作系统生产力的影响

间作作物的播期会影响其共生期,进而影响作物生产力和种间相互作用。为探究谷子(Setaria italic L. Beauv)播期对谷子/花生(Arachis hypogaea L.)间作系统生产力的影响,以谷子金选6号和花生大花生606为试验材料,固定花生播期为5月15日,谷子从5月15日至6月9日每5天播种1期,共设置6个播期处理(S1~S6)。通过对单间作系统中作物产量、产量构成因素等指标的测定,分析不同谷子播期条件下谷子/花生间作的作物产量、系统生产力、种间竞争力的变化。结果表明,随着谷子播期的推迟,间作系统中谷子和花生的产量均表现为先升高后降低的趋势,5月25日播种时(S3)谷子产量(4.07 t·hm^-2)和土地当量比(LER=1.24)最大,5月30日播种时(S4)花生产量(2.51 t·hm^-2)、间作总产值(4.64万元·hm^-2)和间作系统生产力(SP=2.93 t·hm^-2)最大;谷子/花生间作系统的实际产量损失大于0,具有产量优势。谷子的侵占力大于0、竞争比率大于1,花生的侵占力小于0、竞争比率小于1,间作系统中的谷子是竞争优势作物,对资源的竞争能力高于花生且受谷子播期影响较大。相关性分析及通径分析发现,在间作系统中,谷子产量与穗长呈显著正相关,与穗粗、穗重、穗粒重呈正相关,且穗长对谷子产量的贡献作用最大。本研究结果对谷子/花生间作实践具有指导意义。     

Effects of Waxy Maize Relay Intercropping and Residue Retention on Rhizosphere Microbial Communities and Vegetable Yield in a Continuous Cropping System

Intercropping and residue retention contribute to high yield and quality of crops. However, their coupled effects on rhizospheric microbial communities under a continuous vegetable cropping system have not been adequately addressed. The objective of the present study was to assess the effects on soil microbial community and yields of waxy maize(Zea mays L.) intercropped with or without residue retention in a continuous broccoli(Brassica oleracea L.) cropping system, i.e., relay intercropping of broccoli and waxy maize(B/M-B), relay intercropping of broccoli and waxy maize with residue retention(B/MR-B), and broccoli monoculture(B-B). The biomass yields of spring and autumn vegetables in B/MR-B were 16.3%–32.5% and 30.1%–46.1% higher than those of B-B,respectively. Autumn vegetable economic yields of B/MR-B were 28.2%–40.3% higher than B-B. The average well color development followed the order: B/MR-B B/M-B B-B. The Shannon index, Simpson index, and Mc Intosh index were higher in B/MR-B than under monoculture. A principal component analysis showed that microbial communities of B/MR-B soils differed from those of B/M-B and B-B soils. Carbon(C) sources utilized by the rhizosphere microorganisms were mainly carbohydrates, carboxylic acids, amino acids, and polymers; however, the C sources for the soil microbial community differed between intercropping and monoculture. The communities from B/MR-B preferred amino acids and polymers. Available nitrogen(N), potassium(K), and phosphorus(P) had an obvious impact on soil microbial community. Additionally, the C source utilization by microorganisms was significantly affected by p H and available K and P. Cropping system diversification through relay intercropping and residue retention effectively improved the functional diversity of the soil microbial communities and increased the yields of vegetables.     

Aesthetic preferences of non-farmers and farmers for different land-use types and proportions of ecological compensation areas in the Swiss lowlands

Beyond its traditional function of food production, agricultural land offers public amenities such as the protection of natural resources and landscape scenery. This study investigates the preferences of non-farmers and farmers for nine landscape scenarios in the Swiss lowlands. The nine landscapes were the result of a photo editing process combining three land-use types (arable crops, grassland and a mixture of both) and three proportions of ecological compensation areas (0%, 10% and 30%). The landscape photographs were randomly arranged on one page of a paper-based questionnaire which was sent to a random sample of 4000 Swiss households (non-farmers) and 500 farmers. The respondents (1376 non-farmers and 276 farmers) rated each landscape by attractiveness. Both non-farmers and farmers preferred a mixed land-use type or one dominated by arable crops over one dominated by grassland. Non-farmers’ preference ratings were highly influenced by the proportion of ecological compensation areas (ECAs) in the rated landscape: Non-farmers rated a landscape with a mixed land-use type and 30% ECAs highest, whereas farmers rated a landscape dominated by arable crops and 10% ECAs highest. The results indicate that heterogeneous landscapes (mixed land use, high proportion of ECAs) influence scenic beauty positively. Thus, farming practices and agro-environment schemes such as ECAs can have an impact on the visual attractiveness of a landscape.     

水稻与慈姑间作栽培对水稻病虫害和产量的影响

合理的间套作种植能够显著降低病虫害的发生,但已有相关研究主要集中在旱地作物种类或旱稻上,而水田环境下水稻间作体系的作物搭配及种植模式研究目前还十分缺乏。本文通过田间对比试验研究了水稻与慈姑间作栽培对水稻病虫害、微环境以及水稻产量的影响效应。结果表明,间作栽培模式对稻飞虱和稻纵卷叶螟无显著的防控效果。但在拔节期和抽穗期期间,间作栽培模式下水稻纹枯病病丛率分别比单作处理低64.3%和88.2%,稻瘟病病叶率在灌浆期和乳熟期显著低于单作,表明间作栽培模式显著降低了水稻稻瘟病和纹枯病的发生。间作栽培模式下水稻叶片POD、SOD和CAT酶活性与单作模式相比出现了不同程度降低,单作模式下水稻较高的病害发生程度可能是导致叶片保护酶活性增高的原因;间作栽培在早午时段降低了水稻叶片表面的空气湿度,且水稻叶片光合有效辐射强度在多数时段均高于单作栽培,说明间作栽培模式改善了稻田小气候环境,有利于降低病菌的滋生和传播;光合气体交换日进程测定结果表明,灌浆期间水稻/慈姑间作栽培模式下水稻叶片净光合速率、蒸腾速率以及气孔导度在日间大部分时段均高于单作水稻,说明间作栽培模式提高了水稻的群体光能利用率以及群体光合效率;间作栽培模式下的土地当量比为1.17,表明水稻与慈姑间作栽培模式不仅能有效控制水稻病虫害的发生,同时能起到良好的增产效果。