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Cette thèse se propose d'explorer ce que signifie "être agriculteur bio" aujourd'hui en Wallonie. Après une analyse socio-historique du développement de l'agriculture biologique dans cette région d'Europe, la première partie s'attache à comprendre en finesse les parcours de vie des agriculteurs bio wallons, leurs pratiques ainsi que la construction de leurs identités professionnelles. La deuxième partie se penche quant à elle sur les aspects institutionnels de l'agriculture bio :sur la structuration du secteur syndical et associatif ainsi que sur les interactions entre les pratiques des agriculteurs et la législation encadrant l'agriculture biologique. / Doctorat en Sciences politiques et sociales / info:eu-repo/semantics/nonPublished

Thesis (MSc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Food demands for the ever-increasing human population is increasing the pressure on the agricultural sector to produce more food. In order to satisfy these demands, farmers are turning to chemical biocides for the control of pest species to produce greater crop yields. All pesticides must be toxic or poisonous to the target species they intend to control. Unfortunately, most pesticides are toxic or poisonous to non-target organisms as well, with detrimental effects on their health. Organic farming was developed to enhance the overall health of the farm's natural soilmicrobe- plant-animal biodiversity. No synthetic fertilisers and/or pesticides are used when farming organically. Life in the soil consists of intricate food webs and interactions between the soil dwelling invertebrates. The soil-organisms are divided into three main groups, viz., Micro-organisms (e.g. protozoa, bacteria and fungi) mesofauna (nematodes, Collembola and Acari) and macro-fauna (e.g. millipedes, isopods, insects, molluscs and earthworms). The invertebrates are very susceptible to chemical contamination by chemical biocides in natural and agro-ecosystems. The soil invertebrate communities are responsible for the decomposition of organic material in soil, thereby remineralising the soil. The decomposition processes start with comminution of the large pieces of organic material by meso- and macro-fauna and ends with the micro-fauna and microbial organisms that complete these processes by returning the nutrients in an inorganic form to the soil. The aim of this study was to investigate whether, and to what extent the soil organisms are influenced by different management practices viz., organic management practices versus conventional management practices. A vineyard on the farm Plaisir de Merle, in Simondium, Western Cape was used for the present study. One half of a one hectare vineyard was managed organically and the other half conventionally. Within each vineyard block six different treatments were performed. Three of the treatments were strictly organic and the other three were strictly conventional. Four replicates of each management treatment were performed. The bait-lamina technique was used to assess the feeding activity of the soil organisms exposed to the different management treatments. In addition to the bait-lamina trials in the vineyard itself, bait-lamina tests were performed in microcosm studies with soil from the organically and conventionally managed vineyard blocks under controlled conditions. In order to assess the impact of the various pesticides that are used in the vineyards in the conventional way, on the soil fauna, standard acute toxicity tests and behavioural tests were performed on Eisenia fetida, the compost worm. The bait-lamina tests in the vineyard revealed that the moisture content of the soil plays an important role in the biological activity of soil fauna. The different management treatments did affect the biological activity of the soil fauna, but seasonal changes also proved to be one of the important factors governing biological processes in the soil. The acute toxicity tests showed that the active ingredients (mancozeb, penconazole and trifloxystrobin) of three of the pesticides that were tested in this study, had negatively affected E. fetida at their recommended application concentrations. The remaining two pesticides' active ingredients (glyphosate and N-acetyl salicylic acid) did not affect the earthworms negatively at the recommended application concentrations. The preference behavioural trials showed that E. fetida could detect and avoid contaminated substrates at the LCso-concentrations of the different pesticides. All the earthworms were influenced positively in the preference behaviour experiments. Because of certain limitations of the bait-lamina technique, it was difficult to formulate conclusions on what happens in the soil. A possible explanation for the differences in feeding activity of soil fauna could be attributed to the migration of the soil fauna to more habitable soil horizons during the dry summer conditions, when most of the pesticides are applied. The ecological relevance of the acute toxicity tests conducted need to be investigated further. It is clear that the acute toxicity tests provided important information that should be considered, but care should be taken and the necessary safety factors be determined and considered when doing risk assessment studies. The results of the preference behaviour studies showed that for certain pesticides E. fetida can be a sensitive bioindicator of acute and/or sub-acute lethal toxicity testing but this might not necessarily be the case for other pesticides. The goal of doing laboratory studies is to gain as much information to make reliable extrapolations to field situations from laboratory data. Laboratory-to-field extrapolations are very complicated because of the physico-chemical composition of soil, the unpredictable way pesticides behave within soil and the reaction of soil organisms to the soil and to the chemical biocides that are used. Further studies need to be done in order to fully understand to what extent the soil fauna were affected by the different management practices applied to the vineyard at Plaisir de Merle. / AFRIKAANSE OPSOMMING: Voedsel aanvraag vir die toenemende menslike bevolking plaas groot druk op die landbou sektor om meer kos te produseer. Om aan die voedsel eise te voldoen, gebruik boere al meer chemiese biosiede om pesspesies te bestry. Alle pestisiede moet toksies of giftig wees vir die teiken organisme waarvoor dit bestem is. Ongelukkig is die meeste pestisiede ook toksies of giftig vir nie-teiken organismes, wat tot nadelige effekte op hul gesonheid kan lei. Organiese boerdery is ontwikkel om die algehele gesondheid van die plaas se natuurlike grond-mikrobe-plant-dier biodiversiteit te bevorder. Geen sintetiese bemestingstowwe en/of pestisiede mag gebruik word wanneer daar organies geboer word nie. Die lewe in die grond bestaan uit ingewikkelde voedselwebbe en interaksies tussen die grondlewende invertebrate. Die grond invertebrate word verdeel in drie hoof groepe, nl. mikro-organismes (bv. Protozoa, bakterieë en fungi) meso fauna (Nematoda, Collembole en Acari) en makrofauna (bv. Millipoda, Isopoda, Insecta, Mollusca en erdwurms). Die Invertebrata is die mees vatbaarste vir chemiese kontaminasie deur chemiese biosiedes in natuurlike en landbou ekosisteme. Die grond invertebraat gemeenskappe is verantwoordelik vir die afbreek van alle organiese materiaal in die grond en dus vir remineralisering van die grond. Die afbreekproses begin by die komminusie van groter stukke organiese materiaal deur die meso- en makrofauna en eindig met die mikrofauna en mikrobes wat die prosesse voltooi deur die nutriente terug te plaas in die vorm van anorganiese produkte in die grond. Die doel van hierdie studie was om te ondersoek of, en tot watter mate, grond organismes geraak word deur verskillende grondbestuurspraktyke, nl. Organiese grondbestuurspraktyke teenoor die konvensionele grondbestuurspraktyke. 'n Wingerd op die plaas Plaisir de Merle, in Simondium, Wes-Kaap, was gebruik vir die huidige studie. Een helfte van 'n een hektaar wingerd is organies bestuur en die ander helfte is op die konvensionele manier bestuur. Op elk van die twee wingerd blokke is ses verskillende behandelings toegepas. Drie van die behandelings was streng organies en die ander drie was streng konvensioneel van aard. Vier replikate van elke behandeling is toegepas op elk van die twee wingerdblokke. Die bait-lamina metode is gebruik om die voedingsaktiwiteit van die grond organismes te asses seer. As toevoeging tot die bait-lamina proewe in die wingerd self, is bait-lamina toetse ook in mikro-kosmosse in die laboratorium gedoen met grond afkomstig vanaf die twee wingerdblokke. Om die impak van die verskillende pestisiede op die grondorganismes te ondersoek, is standaard akute toksisteitstoestse en gedragstoetse uitgevoer met die komposerdwurm, Eisenia fetida. Die bait-lamina resultate in die wingerd het getoon dat die voginhoud van die grond die belangrikste rol speel wat die biologiese aktiwiteit van die grondorganismes beïnvloed. Die verskillende behandelings het die biologiese aktiwiteit van die grond fauna geaffekteer, maar seisoenale veranderings is ook uitgesonder as een van die bepalende faktore wat die biologiese prosesse in die grond stuur. Die akute toksisiteitstoetse het getoon dat die aktiewe bestandeie van drie van die pestisiede (mancozeb, penconazole en trifloxystrobin), E. fetida negatief beïnvloed het teen die aanbeveelde konsentrasies wat toegedien is. Die aktiewe bestandeie van die ander twee pestiede (glyphosate en N-asetiel sallisiel suur) het nie die erdwurms nadelig beïnvloed teen die aanbeveelde konsentrasies wat toegedien is nie. Die gedragsproewe het getoon dat E. fetida die LCso-konsentrasies van al die verskillende pestisiede kan waarneem en vermy. Al die erdwurms is positief beïnvloed in die gedragseksperimente met die verskillende pestisiede. Omdat die bait-laminametode sekere beperkings het, was dit moeilik om tot gevolgtrekkings te kom oor wat presies in die grond gebeur. 'n Moontlike verklaring vir die verskillende voedingsaktiwiteite van die grond fauna kan toegereken word aan die migrasie van die grondorganismes na meer leefbare grondhorisonne gedurende die droë somer toestande, wat toevallig met die spuit van die meeste pestisiede ooreenstem. Die ekologiese relevansie van die akute toksisiteitstoetse wat uitgevoer is, moet meer deeglik ondersoek word. Die belangrikheid van die akute toksisteitstoetse is duidelik en het waardevolle informasie gelewer, maar sorg moet geneem word, en die nodige veiligheids faktore moet bepaal word en in ag geneem word, wanneer riskobepalingstudies gedoen word. Die gedragsproewe het getoon dat vir sekere pestisiede E. fetida 'n sensitiewe bioindikator van akute en/of sub-akute letale toksisiteits toetse kan wees, maar nie noodwendig vir ander pestisiede nie. Die doel van laboratoriumstudies is om so veel as moontlik inligting te versamelom vertroubare ekstrapolasie te kan maak na situasies in die veld vanaf laboratorium data. Laboratorium-na-veld ekstrapolasies is dikwels baie gekompliseerd as gevolg van die fisies-chemiese samestelling van die grond, die onvoorspelbare manier waarop chemiese pestisiede met die grond reageer en die reaksie van die grondorganismes op chemiese biosiede in die grond. Verdere studies moet gedoen word om so deeglik maanlik die mate van die impak wat die verskillende bestuurspraktyke op die grond fauna het, te verstaan op Plaisir de Merle.

Thesis (MPhil)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The aim of this study was to provide the first in depth description of the natuurboerdery farming system as developed and adopted by ZZ2, a privately-owned farming conglomerate in South Africa. Natuurboerdery aims to increase agricultural productivity and sustainability while maintaining environmental integrity to contribute to overall sustainability. A case study research design using multiple sources and techniques for data gathering was applied to investigate the reasons for and process of converting from conventional farming to natuurboerdery, describe the principles and practices of natuurboerdery farming and document the changes and benefits realised by conversion. It was established that ZZ2 converted to natuurboerdery farming due to the challenges associated with conventional methods of farming. The main challenges ZZ2 experienced were recurrent pests and diseases which were becoming difficult to control with inorganic pesticides, large decreases in yields and unsustainable production outputs or returns to support production costs mainly due to the escalating cost of inorganic pesticides and fertilisers. ZZ2 also became aware of the growing customer demand for healthy food produced by ethically accepted methods while minimising environmental degradation. A conceptual framework was developed to describe the natuurboerdery farming system, based on five principles or health aspects: agro-ecosystem health, soil health, plant health, food health and human health. All of the practices developed and adopted by ZZ2 were described and classified in terms of this framework. Natuurboerdery integrates the use of inorganic fertilisers and organic soil amendments for soil health and plant nutrition; inorganic pesticides, fermented plant extracts from herbal plants with insecticidal properties, EM products, compost teas and biological control agents for plant protection. The conversion to natuurboerdery resulted in changes and benefits which were described and classified under: strategic and technical, economic, social and ecological and environmental. The main findings were that soil health has improved, soil organic carbon levels have increased, the use of inorganic products for plant nutrition and protection has decreased with significant cost savings, yields have risen, water availability has increased and energy spending has been reduced. The conclusions drawn from the research findings indicate that natuurboerdery is neither organic nor conventional farming which indicates that inorganic and organic inputs are compatible in sustainable farming systems. The natuurboerdery farming approach is a potentially sustainable farming system which works with nature. Areas for further scholarship, research and recommendations have been identified to improve the sustainability of natuurboerdery. / AFRIKAANSE OPSOMMING: Die doel van hierdie tesis was om die eerste in-diepte beskrywing van natuurboerdery saam te stel soos dit deur ZZ2 ontwikkel en gebruik is. ZZ2 is ‘n Suid Afrikaanse boerdery konglomoraat in privaatbesit. Natuurboerdery beoog om boerdery produktiwiteit en volhoubaarheid te verhoog, terwyl dit die integriteit van die natuuur in stand hou om tot algehele volhoubaarheid by te dra. ‘n Gevallestudie is as navosingsontwerp gebruik en verskeie bronne en metodes is toegepas om inligting in te samel. Die proses en redes vir die oorskakeling van konvensionele boerdery na natuurboerdery is ondersoek, terwyl die beginsels en praktyke van natuurboerdery beskryf is en die veranderings en voordele van die oorskakeling gedokumenteer is. Dit is vasgestel dat ZZ2 na natuurboerdery omgeskakel het as gevolg van uitdagings wat met konvensionele boerderymetodes gesassosieer word. Die hoof-uitdagings wat ZZ2 ondervind het was terugkerende peste en siektes wat moeilik beheerbaar was met onorganiese plaagdoders, groot afnames van oeste en onvolhoubare produksie uitkomste of winste om die produksiekostes te dra. Stygende pryse van onorganiese plaagdoders en kunsmis was die grootste oorsaak van hoë produksiekostes. ZZ2 het ook bewus geraak van die groeinde klante-aanvraag vir gesonde kos wat op eties-aanvaarbare metodes geproduseer is en skade aan die natuurlike omgewing verminder. ‘n Konsepsuele raamwerk is ontwikkel om natuurboerdery as ‘n boerdery-sisteem te beskryf en is gebasseer om vyf beginsels of gesondheidsaspekte: agroekosisteemgesondheid, grondgesondheid, plantgesondheid, voedselgesondheid en menslike gesondheid. Al hierdie praktyke wat deur ZZ2 ontwikkel en gebruik is word in hierdie tesis beskryf en geklassifisseer in terme van die konsepsuele raamwerk. Natuurbeordery integreer die gebruik van onorganiese kunsmis en organiese grondwysigings vir grondgesondheid en plantvoeding. Geïntegreerde praktyke sluit in: onorganieise plaagdoders, gefermenteerde kruieplant-ekstrakte met insek-bestrydende einskappe, EM produkte, kompos-tees en biologiese beheeragente vir plantbeskerming. Die oorskakeling na natuurboerdery het sekere veranderings en voordele gehad. Dit word geklassifiseer volgens die betrekking wat dit het op die strategiese en tegniese, ekonomiese, maatskaplike en ekologiese en omgewings-aspekte van ZZ2. Die hoofbevindings was verbeterde grondgesondheid, verhoogde organiese koolstofvlakke in die grond, laer gebruik van onorganiese produkte vir plantvoeding en beskerming met noemenswaardige koste-besparings, verhoodge oeste en waterbeskikbaarheid, en kleiner spandering op energie. Die navorsingsbevindings wys daarop dat natuurboerdery nie organies of konvensionele boerdery is nie en dat onorganiese en organiese insette dus verenigbaar is in volhoubare boerdery-sisteme. Die natuurboerdery uitkyk is ‘n potensiële volhoubare boerderysisteem wat in staat is om saam die natuur te werk. Areas vir verdere studie, navorsing en voorstelle is geïdentifiseer om die volhoubaarheid van natuurboerdery te verbeter.

有機農業不僅可產出自然安全的農產品，同時亦得創造優質的農業環境，提供環境公共財與社會公共財，然而這樣的公共財，難以由單一農民提供，而是必須透過同一地區的農民以及利益相關者的共同參與，展開集體行動，才得以有效供給。 宜蘭縣三星鄉行健村是個特殊的案例，有部分農民為推行有機農業，乃成立全台灣第一個由農友組成的有機生產合作社，展開揚棄慣行農法的集體行動，藉由社員互信互助，實踐不施農藥、化肥的栽培，成效初具。然而，行健有機村的知名度雖逐漸提升，但實際上，有機村的名號與實際發展似乎不相襯，目前村內有機耕作面積只佔全村耕作面積的五分之一。因此，本研究以集體行動之理論分析框架，檢視行健村以集體行動促進有機農業發展之可能性。並以文獻分析法、深度訪談法、斷面步行法探究行健村有機農業發展之困境，分析檢討目前的集體行動社會網絡互動模式有何不足之處，期能提供改善建議，以促進該村有機農業發展的可能性。 研究結果顯示該村有機農業發展確實需要集體行動，始能獲致生產及非生產性的共同利益，然而村內網絡間的社會資本不足，以致欠缺發展有機村的共同目標，推展有機農業的集體行動難以擴大，再加上網絡間整合不佳，導致外部資源的投入未有相對應的成效，復又，行健合作社的制度安排不佳，導致營運困境，影響有機村的推展。而中央與地方政府合作不佳，以及現行政府的有機政策導向都關鍵地影響慣性農民轉型有機農業之意願。 本研究認為應增加村內社會網絡間彼此溝通交流之頻度，且行健合作社應重新檢討內部的制度安排，以利促進眾人一心發展有機村之集體行動；而政府方面，應設法改善有機農民之通路、建立有機專區的誘因機制，並且思考補貼政策的轉型，輔以加強消費者食農教育，使有機農業的供需市場擴大並產生互利的良性循環，如此方能讓更多農民願意投入有機耕作，或能真正發展成為兼具生產、生活、生態的「有機村」。 / Organic agriculture not only produces healthy and natural food, but also co-produces environmental public goods and social public goods. However, this kind of goods need to be provided efficiently only by farmers cooperatively, rather than individual. This case study is located in Xingjian village, Sansing Township, Yilan County, where some farmers set up “Xingjian Organic Production Cooperative” to stimulate organic farming development in the village. In this Cooperative, they trust and help each other, trying to persuade other farmers out of using chemical fertilizers and pesticide in farming, and further more, expanding the collective action. To date, some people have been participating in this collective action, as a result, have tackled local agri-environmental issues and provided agri-environmental public goods to some degree. However, as the growing reputation of “Xingjian Organic Village”, the organic farming area only accounts for 20 percent of the total arable land. Therefore, this research using collective action theoretical framework to view the possibility of the Xingjian in promoting organic farming development. This research adopts three ways- literature, in-depth interviews, transect walks, to explore the obstacle of Xingjian village in promoting organic farming development, and to analysis the problem of social network interaction. The result shows that organic agriculture development in the village do need collective action to attain production and non-production of common interests. However, the collective action of organic farming is difficult to expand due to lack of social capital in the village between the networks, and the lack of the common goal in this village. Thus, the input of external resources do not correspond to its performance. Further, institutional arrangements in Xingjian cooperatives functions poor, leading to its operational difficulties. Besides, poor Cooperation between central and local government, as well as the current policy orientation of government, both play a crucial role in affecting farmers' willingness to change conventional farming to organic farming. This study suggests that social networks between the village should connect closely by communicate with each other frequently, and Xingjian cooperatives should review its institutional arrangements, in order to facilitate the collective action of “Xingjian Organic Village”; and the government should try to improve organic produce’s access to market, establish incentives about organic agriculture zone, transfer subsidies policy to organic agriculture, and strengthen consumer’s organic education, so can make more farmers willing to invest in organic farming, or can really develop a production, life and ecology combined "organic village".

The study aimed to investigate the hygiene quality of fresh agricultural produce, irrigation water and compost from four cooperatives (Jabulani, Nungwane, Senzakahle and Siyazenzela) supplying the uMbumbulu Agri-Hub Non-Governmental Organisation. In addition, the influence that socio-economic characteristics such as age, gender, level of education and training had on the uMbumbulu farmers’ hygienic practices was investigated. Questionnaires, key informant interviews and laboratory analysis were used to collect data. The most probable number (MPN) method, a microbiological technique, was used to quantify selected hygiene indicators (i.e. total and faecal coliforms including Escherichia coli) from compost, irrigation water and leafy vegetables (spinach and lettuce) during the months of October, November and December 2011. Microbiological analysis on lettuce and spinach produced by the four Agri-Hub cooperatives confirmed that these vegetables were safe to eat and unlikely to cause sickness. The irrigation water sources, vegetables and compost faecal coliform levels met national standards with faecal coliforms of <1 000 MPN/100ml for irrigation and<200 MPN/g for the leafy salad vegetables. Compost faecal coliform levels were <1000/g and E. coli levels of <30 MPN/g, these levels decreased over the 3 months. Descriptive statistics such as the Chi-Square test using IBM SPSS and a logistic regression was performed using the STATA 11 software. The sample consisted of 60% female and 40% males, most of which (73%) were above the age of 40. A total of 60% of respondents received income from farming activities, receiving revenues of between R150- R250 a week. The logistic regression indicated that farmers already receiving some income from farming activities and those that had received training on hygienic farming practices were likely to wash hands and equipment prior to entering the field compared to those who had not. These variables influenced the hygienic practices with a probability of 26% and 32% respectively at 5% significance level. The logistic regression also showed that respondents with primary or no formal education were less likely to wash hands and equipment prior to entering the field compared to those who had a secondary level education. This unlikelihood had a probability of 35% for primary education and 43% for farmers with no formal education at significance levels of 5% and 10% respectively. This study indicates how training, education and farming experience are important and effective tools in implementing good hygienic practices in small-scale farming. The study’s main recommendations are that policies encourage farmer awareness on their responsibility of producing vegetables that are of good hygienic quality, especially if such produce is to reach the market. Furthermore policies should advocate for small-scale farmer training. This training should not be limited to subsistence farming but should also aim at preparing farmers towards accessing produce markets. Farmer training in hygienic practices should aid farmers to meet the stringent market standards allowing for better access, the regular income from such activities support farming as a livelihood and bearer of food security. It must also be noted that farmers require support in attaining the various resources needed in order to successfully and continually supply markets. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.

Magistrantūros studijų baigiamąjį darbą sudaro 48 psl., 2 lentelės, 20 paveikslų, 54 literatūros šaltiniai, 1 priedas, darbas parengtas lietuvių kalba. Tyrimo objektas – ekologiniai ir kiti ūkininkų ūkiai Kauno rajone. Tyrimo tikslas – išanalizuoti bei įvertinti darnaus ūkininkavimo reikšmę kraštovaizdžiui. Uždaviniai: 1. Išnagrinėti ir apibendrinti darnaus ūkininkavimo požymius; 2. Atskleisti kraštovaizdžio įtaką darniam ūkininkavimui; 3. Atlikti Kauno rajono ekologinių ir kitų ūkininkų ūkių darnaus ūkininkavimo reikšmės tyrimą kraštovaizdžiui. Darbe apibendrinti Lietuvos ir kitų šalių autorių moksliniai tyrimai, susijusieji su darnaus ūkininkavimo plėtros procesais, kurie skatina ekologinio ūkininkavimo perspektyvas ir saugo patį kraštovaizdį. Dėl ES pagalbos žemės ūkio sektoriui atsiranda įsipareigojimų, savo ūkius padaryti patrauklius, moderniai ūkininkaujant sumažinti neigiamą poveikį aplinkai ir tvarkytis taip, kad darnus ūkininkavimas natūraliai įsilietų į kraštovaizdį, nes stambėjant ūkininkų ūkiams dalinai nukenčia kraštovaizdis. Atlikus tyrimą nustatytas ryškus ekologinės žemdirbystės ūkių gausėjimas pereinamuoju laikotarpiu, 2010–2013 metais. Nors ekologinių ūkių skaičius pradėjo mažėti, tačiau sertifikuotas ekologinės gamybos plotas ir toliau auga. Tyrimo metu paaiškėjo, kad ūkininkai norėtų didesnių motyvuojančių išmokų efektyviai ekologinei gamybai (ūkis be paramos būtų nuostolingas). Taip pat jie pripažįsta, kad dėl darnaus ūkininkavimo gražėja kraštovaizdis... [toliau žr. visą tekstą] / Master‘s final work consists of 48 pages, including 2 tables, 20 pictures, 54 literature sources and 1 appendix. It was written in Lithuanian language. The object of the research – organic and other farmers‘ farms in Kaunas district. The aim of the research – to analyze and evaluate the significance of sustainable farming on the landscape. Tasks that were solved: 1. Features of the sustainable farming were analyzed and summarized; 2. The influence of the landscape upon sustainable farming was showed; 3. The research of the significance of the sustainable farming of organic and other farmers‘ farms of Kaunas district was carried out. In the work scientific researches related with the sustainable farming development processes were summarized, which stimulate organic farming and protect the landscape itself. Due to the EU's assistance to the agricultural sector liabilities occur to make farms attractive, to reduce the negative impact on the environment and manage in the way that sustainable farming naturally spilled into the landscape, as with the farmers’ farms getting bigger landscape is partially affected. The survey results show the significantly increasing number of farms of organic farming in the transition period of 2010-2013. Although the number of organic farms began to decline, the certified organic area continues to grow. The study revealed that farmers would like to receive larger motivating benefits for the efficient organic production. They also recognize that... [to full text]

Dans le contexte politique (réduction 50% de l’utilisation des pesticides à échéance de 2018 -Plan Ecophyto) et social actuel (mise en place de modes de production plus respectueux pour l'environnement), la sévérité des dommages causés par le puceron cendré du pommier, Dysaphis plantaginea Passerini (Hemiptera : Aphididae), surtout en agriculture biologique, rend nécessaire la mise au point de solutions alternatives s’appuyant sur le rôle des ennemis naturels. Nous avons donc essayé d’apporter des éléments nouveaux sur la connaissance des relations entre le puceron cendré et ses ennemis naturels et sur les conditions à même de favoriser leur action. Des suivis hebdomadaires des arthropodes présents sur les rameaux infestés par D. plantaginea, ont mis en évidence l’effet négatif des auxiliaires sur les populations de D. plantaginea, sans pour autant atteindre une véritable régulation à même d’éviter les dégâts économiques. Nous avons également montré l’action favorisante des fourmis sur la dynamique du puceron cendré et négative sur celle des auxiliaires. Nous avons pu identifier trois groupes d’auxiliaires dominants avec une arrivée séquentielle marquée : les syrphes, dont l’installation coïncide avec le début de l’infestation de D. plantaginea, puis les coccinelles et les forficules qui arrivent plus tardivement. Pour que les auxiliaires jouent un rôle plus important contre D. plantaginea, il faut d’autres pratiques permettant d’abaisser significativement le nombre de traitements pesticides. Une innovation très récente permet la réduction drastique des traitements insecticides : les filets Alt’Carpo. Malgré son influence négative sur l’abondance et la richesse du cortège des auxiliaires présents dans les colonies de D. plantaginea, surtout les coccinelles, cette technique freine le développement des populations de D. plantaginea à l’échelle du rameau ou de l’arbre lorsque les filets sont fermés après la floraison (en conformité avec les préconisations contre le carpocapse). Cependant, la réduction des populations de D. plantaginea sous les filets requiert la présence d’au moins un stade actif d’auxiliaire par rameau, ce qui interroge sur la réalité de la régulation de ce ravageur par le simple usage des filets. Sur la base de leur précocité, pour Episyrphus balteatus De Geer (Diptera : Syrphidae) et de leur abondance dans les colonies de D. plantaginea, pour Forficula auricularia Linnaeus (Dermaptera : Forficulidae) et E. balteatus, ces deux espèces apparaissent comme de bons candidats pour la régulation de D. plantaginea. Nos études en conditions contrôlées ont démontré leur potentiel régulateur sur D. plantaginea, en particulier aux stades les plus âgés. L’efficacité optimale intervient à 20°C pour les deux prédateurs, pour lesquels nous n’observons par ailleurs pas d’interaction négative lorsqu’ils sont associés en présence de fortes densités de D. plantaginea. Sur la base de ces résultats de laboratoire nous avons analysé les possibilités de lâchers printaniers de ces deux prédateurs sur de jeunes colonies de D. plantaginea. Dans nos conditions expérimentales en vergers de pommiers, des lâchers précoces de larves du 3ème stade de F. auricularia n’ont pas permis de limiter les populations de D. plantaginea, confirmant la difficulté des lâchers de prédateurs en cultures de plein champ. De la même manière, des lâchers précoces d’E. balteatus pourtant réalisés sous filets Alt’Carpo restent sans effet sur l’infestation par D. plantaginea. Cette thèse, en s’appuyant sur des essais en conditions contrôlées, semi contrôlées et de plein champ, constitue une étape dans un processus d’élaboration d’un modèle dynamique du développement de D. plantaginea à l’échelle du rameau, prenant en compte le rôle des fourmis et des auxiliaires et l’influence des pratiques de protection (par exemple, les filets Alt’Carpo et les lâchers d’auxiliaires). Elle confirme, si besoin en était, la complexité des phénomènes de régulation, des pucerons en particulier, et la nécessité d’études complémentaires pour définir les conditions d’application de la lutte biologique contre D. plantaginea / In the current political and social context (reduced use of pesticides), there is a need for the development of alternative solutions to control the rosy apple aphid, Dysaphis plantaginea Passerini (Hemiptera : Aphididae), especially in organic farming. One of these alternatives is the increased and improved use of natural enemies against this pest. In this thesis, we provided some elements of responses regarding this problem in term of research study and technical application. Based on weekly observations of arthropods in marked shoots infested by D. plantaginea, we demonstrated the negative effects of the natural enemies on the development of D. plantaginea but this effect was unsufficient to provide an effective regulation avoiding economic damages. We also showed the possible and positive influence of ant presence on the infestation dynamics and thei rnegative effect on natural enemies. Among the natural enemy groups, three were the most abundant and appeared in a temporary sequence : syrphids arrived first, at the beginning of the infestation,followed by coccinellids and earwigs that arrived later.To enhance the role of the natural enemies against D. plantaginea, we also need other practices that enable to reduce significantly the number of pesticide applied. This is the case of a very recent innovation : the Alt'Carpo nets. Despite its negative influence on the abundance and richness of the natural enemies, especially the coccinellids, present in the colonies of D. plantaginea, there was a negative influence of these nets on the development of D. plantaginea populations (both at the shootand tree levels) especially when the nets were closed in mid-April (coinciding with classical netting trees for controlling populations of codling moth). We additionally showed that the highest reductionin D. plantaginea population was observed in the presence of at least one active natural enemy in the marked shoot. This gives support to the combination of these methods of control, one biological and the other physical, to regulate D. plantaginea populations. Based on their precocity for Episyrphus balteatus De Geer (Diptera : Syrphidae) and their abundance for both Forficula auricularia Linnaeus (Dermaptera : Forficulidae) and E.balteatus observed under field conditions, the syrphids and earwigs appear as good candidates for controlling the D. plantaginea populations. We first demonstrated under laboratory conditions using detached plantain leaves in Petri dishes conditions the potency of these two predators, especially a tolder stages, against D plantaginea. The optimal predation occurred at 20°C for both predators. Using young apple trees, we further studied the possible interactions between these predators and showed a small and positive interaction when the D. plantaginea density was not limiting. But at low densities of aphids, the results suggested a possible negative interaction (a sign of intraguild predation) between these two predators. These results from laboratory studies have led us to study the augmentative release of these two predators, under field conditions, in early spring for controlling D. plantaginea populations. The releases of F. auricularia (third instar nymph) did not result in lower D. plantaginea populations. This confirmed the difficulty of successful releases of natural enemies under theconditions of open orchards, and demonstrated the need for improving or creating conditions that canpromote the success of the released natural enemies. However, despite closed conditions, the early release of E. balteatus under Alt'Carpo nets was also not efficient against D. plantaginea.This thesis, through several studies under different conditions (controlled, semi-field and field), represented an important first step that should ideally lead to the development of a dynamic model of the development of D. plantaginea at the shoot level, taking into account the presence of ants and therole of natural enemies and the influence of some agricultural practices (for example Alt'Carpo nets and natural enemy releases). Further studies are also needed to validate our results (effects of Alt'Carpo nets) and to optimise the releases of natural enemies

A crescente necessidade de alimentos objetivando a satisfação da nutrição animal em sistemas orgânicos, aliado ao recente mercado mundial desse tipo de produtos, tem suscitado a elevada preocupação com o aperfeiçoamento de sistemas orgânicos, incluindo a produção de milho. Assim, neste contexto, foi realizado no município de Piracicaba, SP, Brasil, em área pertencente à Escola Superior de Agricultura Luiz de Queiroz/Universidade de São Paulo, um experimento de campo objetivando a avaliação do desempenho e produtividade de milho consorciado a adubos verdes, em sistema orgânico de produção. Para tanto, foram utilizados dois genótipos, um híbrido (Pioneer 30P70) e uma variedade (BRS4157 Sol-da-manhã), consorciados a duas espécies de adubos verdes (Crotalaria juncea e Canavalia ensiformis) e submetidos a doses crescentes de nitrogênio, mediante o uso de farinha de chifre, perfazendo o total de 18 tratamentos e 3 repetições. O delineamento adotado foi o esquema fatorial 3X9, em blocos ao acaso, envolvendo a interação de genótipos, adubos verdes e doses de nitrogênio. A análise dos resultados, permitiu concluir que: a)o híbrido Pioneer 30P70 é mais produtivo e apropriado para sistemas orgânicos de produção, com o uso de fontes de nitrogênio, em comparação à variedade Sol-da-manhã; b)A variedade Sol-da-manhã não responde satisfatoriamente ao emprego de doses crescentes de nitrogênio, representadas pelo uso de farinha de chifre;c)A farinha de chifre não contribui, de forma imediata, para a elevação dos teores de nitrogênio nas plantas de milho, até os níveis considerados adequados para a espécie; d)Sistemas consorciados de milho com crotalaria (Crotalaria juncea) ou feijão-de-porco (Canavalia ensiformis) não afetam a produtividade do mencionado cereal e e) As espécies de adubos verdes avaliadas não contribuem significativamente para o aporte de nitrogênio às plantas de milho a eles associadas, durante o ciclo vital do referido cereal. / The increasing need for feed to fulfill animal nutritional requirements in organic systems, besides the increasing world demand for organic products, has raised a concern about the improvement of organic systems, including maize production. Within this context, an experiment aiming at evaluating the performance and yield of corn intercropped with green manures in an organic production system was carried out in Piracicaba, SP, Brazil at the Escola Superior de Agricultura Luiz de Queiroz / University of Sao Paulo. Two maize genotypes were tested, a hybrid (Pioneer 30P70) and a variety (BRS4157 Sol-da-manhã), both intercropped with two green manure species (Crotalaria juncea and Canavalia ensiformis) and submitted to increasing N doses by horn meal, adding up to 18 treatments and 3 replicates. The plot design was factorial 3x9, in randomized blocks involving the genotypes interaction, the green manures and nitrogen doses. The results analysis allowed the following conclusions: a) When fertilized with N sources, the hybrid Pioneer 30P70 is more productive and more suitable for organic systems compared to the variety Sol-da-manhã; b) the variety Sol-da-manhã does not have a response to increasing N fertilization; c) the horn meal does not contributes immediately to the increasing amount of N in maize plants up to the nutritional level suitable for the species; d) the intercropping systems between maize and sun hemp (Crotalaria juncea) or jack bean (Canavalia ensiformis) do not affect the cereal yield and e) the evaluated green manures species do not significantly contribute with the N supply of the associated maize plants during its life cycle.

Agricultores e técnicos envolvidos na citricultura orgânica procuram desenvolver sistemas de produção com maior atividade microbiana no solo. Dessa maneira, esperam obter benefícios dos processos que ocorrem no solo, entre eles, o controle natural de pragas e doenças. Porém, são poucos os estudos sobre a influência desse tipo de manejo sobre a microbiota do solo, em especial sobre os fungos micorrízicos arbusculares (FMAs) e o patógeno Phytophthora parasitica. Os objetivos dessa tese foram: avaliar a colonização micorrízica e conhecer a diversidade de FMAs nos sistemas de produção convencional e orgânico de citros; avaliar a aplicação de benomyl e da radiação &#947; na obtenção de testemunhas não micorrizadas para estudo de interação de comunidade de FMAs nativos e P. parasitica; verificar a capacidade indutora de resistência local e sistêmica dos FMAs nativos a P. parasitica; estudar atividade da quitinase no sistema radicular de limão 'Cravo' colonizado por fungos micorrízicos nativos. Foram realizadas amostragens em dois sistemas de produção de citros em São Paulo, um convencional e um orgânico. A riqueza e a diversidade de espécies de FMAs foram maiores no manejo orgânico. No entanto, a porcentagem de colonização micorrízica nas plantas no campo não variou com o tipo de manejo. Em casa de vegetação, experimentos com plantas de limão 'Cravo' (Citrus limonia) mostraram que a radiação &#947; foi mais adequada que a aplicação de benomyl na obtenção de testemunhas não micorrizadas para estudo de interação P. parasitica- FMAs nativos de agroecossistemas de produção de laranja. Também em casa de vegetação, foi realizado um experimento com raiz dividida de plantas de limão 'Cravo'. Não foi possível avaliar a capacidade indutora de resistência dos fungos micorrízicos arbusculares nativos porque não houve desenvolvimento da podridão de raízes nas plantas de limão 'Cravo' após a infestação com P. parasitica. Discute-se a interação de patógenos de raiz do solo natural e os FMAs nativos porque o solo natural dos sistemas de produção convencional e orgânico promoveram diferentes respostas de crescimento local e sistêmico das raízes das plantas micorrizadas. A atividade de quitinase foi igual nas raízes de plantas micorrizadas e não micorrrizadas cultivadas em solos dos sistemas de produção convencional e orgânico. Porém, a associação micorrízica aumentou localmente a proteína total nas raízes das plantas. / Farmers and technicians involved with organic citriculture try to develop systems with high microbial activity in soil. In this way, they expect to obtain benefits from processes that occur in soil, as natural control of pests and diseases. However, there are few studies about the influence of this type of management on soil microbiota, specially on the arbuscular mycorrhizal fungi (AMF) and the pathogen Phytophthora parasitica. The objectives of this thesis were: to evaluate mycorrhizal colonization and diversity of AMF in citrus conventional and organic farming; to evaluate benomyl application and &#947; radiation to obtain non-mycorrhizal controls for study of interaction between indigenous AMF and P. parasitica; to verify local and systemic capacity of indigenous AMF to induce resistance against P. parasitica; to study chitinase activity in roots of 'Rangpur' lime colonized by indigenous AMF. Samplings were carried out in two citrus systems in São Paulo, one conventional and one organic farming. The richness and the diversity of AMF species were higher in the organic farming. In greenhouse, experiments with 'Rangpur' lime (Citrus limonia) showed that &#947; radiation was better than benomyl to obtain non-mycorrhizal control for studies of interaction between P. parasitica-indigenous AMF from orange agroecosystems. In greenhouse also, a split root experiment with 'Rangpur' lime was carried out. It was not possible to evaluate the indigenous AMF capacity to induce resistance because no root rot developed in 'Rangpur' lime plants after inoculation with P. parasitica. We discuss the interaction between root pathogens in natural soil and indigenous AMF because natural soil from conventional e organic farming promoted different local and systemic root growth responses in mycorrhizal plants. Chitinase activity was similar in roots of mycorrhizal and non-mycorrhizal plants grown in conventional and organic farming soils. However, mycorhizal association increased local protein content in roots.