Resumo: Com o intuito de agregar valor a frutas nacionais desidratadas, os efeitos de pré-tratamentos sobre a secagem de mamão Formosa foram avaliados. Para tanto, foram utilizados previamente à secagem convectiva o branqueamento, a desidratação osmótica (DO) e a aplicação de coberturas comestíveis na superfície das frutas frescas e osmoticamente desidratadas. Com base em um planejamento fatorial, verificou-se que a DO das fatias de mamão frescas e branqueadas em solução de sacarose a 50% p/p adicionadas de 1% p/p de lactato de cálcio e 0,1 M de ácido lático por 120 min e 105 min, respectivamente, foram as condições que ocasionaram redução na atividade de água das amostras e pequenas variações em sua cor. A cinética de DO das frutas frescas e branqueadas mostrou que o branqueamento resultou em maiores coeficientes de difusão da água e dos solutos. Melhores ajustes para as difusividades das fatias de fruta foram verificados considerando-as como placas infinitas. Os resultados evidenciaram grande atividade de invertase no mamão, o qual se apresentou como uma fonte potencial para a extração da referida enzima. As isotermas de sorção de fatias frescas, branqueadas e desidratadas osmoticamente de mamão Formosa mostraram que mais energia foi necessária para a remoção da água das amostras osmoticamente tratadas e que a dessorção das frutas branqueadas exigiu menor quantidade de energia. O branqueamento danificou a estrutura celular dos mamões resultando em maiores coeficientes de difusão da água que as frutas frescas durante a secagem. A desidratação osmótica dos mamões e a cobertura aplicada na superfície das frutas também resultaram em maiores coeficientes de difusão da água em relação às amostras frescas. A cobertura exerceu efeito protetor... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Aiming to add value to national dehydrated fruits, the effects of pre-treatments on convective drying of papaya of Formosa cultivar were investigated. Blanching, osmotic dehydration (OD) and edible coating application at the surface of fresh and osmotically dehydrated fruits were evaluated. Based on a factorial design, it was verified that OD of fresh and blanched papayas sucrose solutions at 50% w/w added with 1% w/w of calcium lactate and 0,1 M of lactic acid for 120 and 105 min, respectively, were the conditions resulting in decreased water activity and small color changes. OD kinetics of fresh and blanched fruits showed that blanching resulted in higher water and solutes diffusion coefficients. The best adjustments for the fruit diffusivities were obtained considering them as infinite slabs. The results revealed the great invertase activity in papaya which presented as a potential source for the referred enzyme extraction. Sorption isotherms of fresh, blanched and osmo-treated papayas showed that more energy was necessary to remove water from osmotically dehydrated samples and the dessorption of blanched fruits needed lower quantity of energy. Blanching damaged the cellular structure of papaya resulting in higher moisture diffusivities than the fresh fruits during drying. Osmotic dehydration and the coating applied at the surface of the fruits also resulted in higher moisture diffusion coefficients in relation to the fresh samples. Coating presented a protective effect on carotenoids content of the samples when applied at fresh fruits surface. Retention of vitamin C of fresh coated fruits was higher than the non-coated fresh and blanched papayas. Osmotic treatment did not have a protective effect on nutritional compounds of papayas, resulting in dried fruits with reduced vitamin C content / Orientador: Maria Aparecida Mauro / Coorientador: Mieko Kimura / Banca: Vânia Regina Nicoletti Telis / Banca: Roger Darros-Barbosa / Banca: Celso Costa Lopes / Banca: Joel Fernando Nicoleti / Doutor

Made available in DSpace on 2014-06-11T19:29:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-30Bitstream added on 2014-06-13T20:39:10Z : No. of bitstreams: 1 ciocchi_eb_me_ilha.pdf: 478816 bytes, checksum: dedf03f7d5d4b3902e9ba7d3dba394e1 (MD5) / O molibdênio é essencial no processo de fixação simbiótica do nitrogênio por ser constituinte da enzima nitrogenase. O uso de sementes enriquecidas com molibdênio é uma das formas práticas de fornecimento do nutriente às plantas de soja. Neste contexto, desenvolveu-se o presente trabalho objetivando determinar em diferentes cultivares de soja, a dose de molibdênio a aplicar nos estádios reprodutivos para elevar o teor do mesmo na semente (sementes enriquecidas), bem como possíveis alterações na produtividade e massa das sementes e qualidade fisiológicas destas. O trabalho foi desenvolvido no ano agrícola 2005/06, na Fazenda de Ensino, Pesquisa e Extensão/UNESP - Campus de Ilha Solteira, localizada no município de Selvíria – MS (51º22’W, 20º22’S e altitude 335 m aproximadamente), em um Latossolo Vermelho distrófico típico argiloso. O delineamento experimental utilizado foi o em blocos casualizados, com os tratamentos dispostos em um esquema fatorial 6x2x2 com quatro repetições, ou seja, seis doses de molibdênio (0, 200, 400, 600, 800, 1000 g/ha) aplicadas através de pulverização foliar (dose única aplicada no estádio R5.4 ou parcelada, sendo metade em R3 e metade em R5.4), em dois cultivares de soja (MSOY 7901 e MG/BR 46). As avaliações constaram de: características agronômicas, produtividade, massa de 100 sementes, teor de molibdênio nas sementes, germinação e condutividade elétrica. Pelos resultados obtidos, verificou-se que a produtividade de grãos não é influenciada pela aplicação foliar de doses de molibdênio, em estádios reprodutivos da soja; a massa de 100 sementes responde de forma linear a aplicação de doses crescentes de Mo quando aplicadas em dose única; a cultivar MSOY 7901 apresenta sementes com maior teor de Mo e sendo recomendado a aplicação em dose única; o teor de molibdênio nas sementes tem comportamento... / Molybdenum is essential in the symbiotic fixation process of nitrogen due to its participation on nitrogenase enzyme. The use of seeds enriched with molybdenum is one of the practical forms of supplying the nutrient to the soybean plants. In this context, the present study was developed to determine in different cultivars of soybean, doses of molybdenum applied in the reproductive stage for elevating the Mo seed content (seeds enriched), as well the possible alterations in the productivity, on mass and physiological seed quality. The experiment was conducted in the agricultural year 2005/06, at experimental area belonging to UNESP – Ilha Solteira Campus, located in Selvíria county – MS (51º22’W, 20º22’S and altitude 335 m approximately), in a clayey dystrophic Red Latosol. A randomized block design was used, in a factorial scheme 6x2x2 with four repetitions, or be, six doses of molybdenum (0, 200, 400, 600, 800, 1000 g/ha) applied on the leaves through spraying (unique dose applied in the stadium R5.4 or divided in two applications, being half in R3 and other half in R5.4 stadium), in two cultivars of soybean (MSOY 7901 and MG/BR 46). The evaluations were: agronomic characteristics, productivity, mass of 100 seeds, content of molybdenum in the seeds, germination and electrical conductivity. Through the results obtained, it was verified that the productivity of seeds was not influenced by leaf application of Mo doses, in reproductive stage of the soybean; the mass of 100 seeds fitted to a lineal equation to doses of Mo application when applied in unique dose; the MSOY 7901 cultivar presented seeds with higher Mo content and being recommended the application in unique dose; the Mo content on seeds fitted a quadratic equation as a function... (Complete abstract click electronic access below)

O presente experimento foi conduzido na Unidade Experimental de Plantas Forrageiras (UEPF) em área do Departamento de Produção Animal da ESALQ/USP, em Piracicaba (SP), entre 01/07/98 e 31/12/98. Os tratamentos consistiram de combinações entre três cultivares de Cynodon spp. (Tifton-85, Florakirk e Coastcross) e quatro intensidades de pastejo (5, 10, 15 e 20 cm) estabelecidas por ovinos em regime de lotação contínua. O delineamento experimental foi o de blocos completos casualizados com quatro repetições e parcelas sub-divididas, onde na parcela foram alocados os cultivares e na sub-parcela as intensidades de pastejo. Foram analisadas as seguintes variáveis: índice de área foliar, interceptação luminosa, acúmulo de matéria seca e composição botânica/morfológica dos pastos. Tifton 85 mostrou os maiores valores de IAF para qualquer das intensidades de pastejo estudadas. As taxas de acúmulo de matéria seca foram semelhantes em todos os tratamentos. Tifton 85 apresentou como faixa ótima de uso condições de pasto que variaram de 5 a 15 cm. Já para Florakirk essa faixa foi até 20 cm e para Coastcross o limite superior deve ser maior que 20 cm. De maneira geral os diferentes cultivares devem possuir requerimentos variados de manejo de desfolha quando o objetivo é o uso eficiente da luz e demais fatores de crescimento associado a elevados índices de utilização da forragem produzida. / The present trial was carried out at the Pasture and Grazing Studies Unit, Animal Production Department, ESALQ/USP, Piracicaba, State of São Paulo, from July 1 until December 31, 1998. Treatments comprised the possible combinations between three Cynodon spp. cultivars (Tifton-85, Florakirk and Coastcross) and four grazing intensities (5, 10, 15 and 20 cm) imposed by sheep under a continuous stocking management. Treatments allocation to experimental units followed a completely randomised block design with four replications and a split-plot arrangement. Grass cultivars were allocated to plots and grazing intensities to sub-plots. The responses studied were leaf area index (LAI), light interception, herbage dry matter accumulation and swards' botanical composition. Tifton-85 showed the highest LAI for any of the grazing intensities used. Herbage dry matter accumulation rates were similar for all treatments. Tifton-85 presented a narrower range of sward conditions for grazing management (5 to 15 cm) when compared to Florakirk (5 to 20 cm) and Coastcross (5 to > 20 cm). Overall, different grass cultivars presented different grazing management requirements in situations where efficient use of light and high levels of herbage utilisation are targeted.

Made available in DSpace on 2014-08-20T13:44:39Z (GMT). No. of bitstreams: 1 dissertacao_jacson_zuchi.pdf: 293310 bytes, checksum: e34d732288d3fcfbddf307f0984f9fff (MD5) Previous issue date: 2008-02-18 / The sowing season definition is an important operation step in a crop. The sowing season can also play a great effect on the yield and castor bean seed quality (Ricinus communis L.). Thus the objective of this study was to evaluate the yield and the seed quality of four castor bean cultivars on two sowing season and in two cropping systems. The cultivars were used in this study, that are IAC 226, IAC 80, Al Guarany 2002 and BRS 188 Paraguaçu, where, the first sowing was November and the other was December, each season was settle in 12 experimental units in each crop system. The experimental design was randomized complete blocks with 3 replications. The following evaluations were done: emergence, insertion height of the central spike, plant height, number of spikes per plant, number of spikes per bloom, flowering period, harvest period, yield, hull percentage, weight of seed thousand, seed vigor, germination and dormancy degree. Based on the results, the following conclusions were taken: 1 - The sowing season played a role on castor cultivars behavior, but did not affect the seed yield. 2 - The BRS Paraguaçu 188, IAC 226 and Al Guarany 2002 cultivars produced seeds with higher quality in the first sowing season, while the IAC 80 cultivar produced seeds with higher quality in the second sowing season. / A definição da época de semeadura é uma etapa importante na exploração de uma cultura agrícola. A época de semeadura também pode exercer grande influência quanto ao rendimento e qualidade das sementes de mamona (Ricinus communis L.). Assim, o objetivo do presente estudo foi avaliar a produtividade e a qualidade de sementes de quatro cultivares de mamona em duas épocas de semeadura sob dois sistemas de cultivo. As quatro cultivares utilizadas foram, IAC 226, IAC 80, Al Guarany 2002 e BRS 188 Paraguaçu, semeadas no início de novembro e início de dezembro, em que cada época constitui-se de 12 unidades experimentais, em cada sistema de cultivo. O delineamento experimental foi de blocos casualizados com três repetições. Foram realizadas avaliações de emergência, altura de inserção do primeiro cacho, altura de planta, número de cachos por planta, número de cachos por floração, período de floração, período de colheita, produtividade, percentagem de casca, peso de 1000 sementes, vigor, germinação e grau de dormência nas sementes. Com base nos resultados obtiveram-se as seguintes conclusões: 1 - A época de semeadura influencia o comportamento das cultivares de mamona, porém não influencia a produtividade de sementes; 2 - As cultivares BRS 188 Paraguaçu, IAC 226 e Al Guarany 2002 apresentam sementes de maior qualidade na 1ª época de semeadura, enquanto que a cultivar IAC 80 apresenta na 2ª época de semeadura.

Les anthocyanes constituent une composante importante de la qualité des fruits rouges, particulièrement pour le raisin noir, et pour la couleur des vins qui en dérivent. La biosynthèse des anthocyanes est déterminée par des facteurs génétiques et affectée par des facteurs environnementaux, notamment la lumière. Pour la plupart des cépages, la pellicule des baies est le tissu principal ou exclusif accumulant les anthocyanes. Notre travail analyse les effets de la lumière et du génotype sur la biosynthèse des anthocyanes. Le matériel végétal que nous avons utilisé était constitué de cépages teinturiers, qui accumulent des anthocyanes dans la pellicule et dans la pulpe, et de populations hybrides. Dix-neuf anthocyanes mono-glycosylées ont été identifiés dans sept tissus colorés du cépage teinturier Yan-73 (V. vinifera). La composition et la concentration en anthocyanes varient selon les organes et le stade de développement. Les anthocyanes de la pellicule incluent principalement les dérivés de la malvidine, alors que les dérivés de la péonidine sont les plus abondants dans la pulpe. Les dérivés de malvidine et de péonidine prédominent dans le rachis, les pédicelles des baies, les limbes foliaires, les nervures et les pétioles, et dans l‘écorce à la base du cep. Les concentrations des anthocyanes dans les pellicules, la pulpe, le rachis et les pédicelles augmentent rapidement à partir de la véraison, ou une semaine après la véraison. Elles sont élevées dans les limbes foliaires jeunes et sénescents, et faibles dans les feuilles en expansion et les feuilles adultes. Elles ne varient pas beaucoup au cours de la saison dans les nervures et les pétioles, ou dans l‘écorce. Les cépages ont pu être distingués selon leur réponse à des traitements d‘exclusion de la lumière imposés de la nouaison à la maturité en entourant les grappes par des boîtes opaques. Le cépage non teinturier ―Gamay‖ à peau rouge accumule très peu d‘anthocyanes dans la pellicule en absence de lumière. Au contraire, les cultivars teinturiers, ‗Yan-73‘ et ‗Gamay Fréaux‘ (mutant teinturier de ‘Gamay’) accumulent des anthocyanes aussi bien dans la pellicule que dans la pulpe et présentent une coloration sombre même en absence de lumière... / Anthocyanins are an important component of red fruit quality, especially for grape berries, and for the color of the wines made from these berries. Anthocyanin biosynthesis is determined by genetic factors and affected by environmental factors, especially sunlight. For most grape cultivars, the berry skin is the main or only tissue accumulating anthocyanins. The present work investigates the effects of light and grape genotype on anthocyanin biosynthesis. We used teinturier grape cultivars (also called dyers, which synthesize anthocyanins in both skin and pulp) and its hybrid population as plant materials. Nineteen monoglucoside anthocyanins were identified in seven colored tissues of the teinturier cultivar Yan-73 (V. vinifera). Anthocyanin composition and concentration varied among grape organs and with developmental stage. Skin anthocyanins were mainly composed of malvidin derivatives, while peonidin derivatives were the most abundant anthocyanins in the pulp. Both malvidin and peonidin derivatives were predominant in rachis, berry pedicels, leaf lamina, vein and petioles, and living bark at the base of the shoot. The concentration of anthocyanins in berry skin, pulp, rachis and pedicels rapidly increased starting from veraison on, or one week after veraison. Anthocyanin concentrations were high in young and senescing leaf lamina and low in expanding and mature lamina. They did not vary much throughout the growing season in the leaf veins and petiole tissues, or in the bark. Grape cultivars could be distinguished by their response to sunlight exclusion treatments imposed from fruit set to maturity by surrounding the clusters with opaque boxes. The red-skinned non-teinturier cultivar Gamay could barely accumulate anthocyanins in berry skin under sunlight exclusion. In contrast, teinturier cultivars, Yan-73 and Gamay Fréaux (teinturier mutant of Gamay) accumulated anthocyanins in both skin and pulp and showed dark color even under sunlight exclusion...

Les changements de contexte économique, réglementaire et environnementaux auxquels la production agricole doit faire face nécessitent d'évaluer de nouvelles stratégies de gestion conjointe de l'irrigation et de la fertilisation pour blé dur. Le travail de thèse a suivi un double objectif : i) adapter le modèle de culture STICS à différents cultivars de blé dur, et ii) concevoir un modèle de décision des pratiques de fertilisation azotée et d'irrigation. Une base de données comportant 373 traitements expérimentaux issus de douze années climatiques a été constituée à partir d'expérimentations réalisées avant la thèse à l'INRA et ARVALIS puis mobilisée pour conduire le travail d'adaptation et d'évaluation du modèle de culture. L'adaptation du modèle de culture a consisté dans un premier temps en un travail d'estimation de paramètres par optimisation mathématique pour sept cultivars de blé dur. Une analyse comparative de trois démarches a permis de sélectionner la démarche pertinente pour obtenir un modèle précis et robuste pour la simulation du rendement, de la teneur en azote des grains et des variables intermédiaires (Biomasse aérienne, surface foliaire, quantité d'azote absorbée) dans différents contextes pédo-climatiques (large gamme de niveaux de nutrition hydrique et azotée). Cette étude fournit un cadre méthodologique pour l'estimation des paramètres des modèles de culture. Les résultats de ce travail ont de plus démontré que le modèle de culture, avec son formalisme initial, n'était pas sensible à l'effet du fractionnement de la fertilisation sur la quantité d'azote et la teneur en azote des grains. L'adaptation est appréhendée dans un deuxième temps par la modification du formalisme d'accumulation de l'azote dans les grains par l'introduction d'un formalisme inspiré du modèle AZODYN. La modification n'a pas amélioré suffisamment la sensibilité du modèle à l'effet du fractionnement sur la teneur en azote des grains. Le manque de données expérimentales en phase post-floraison et notamment la dynamique de la sénescence foliaire n'a pas permis d'améliorer la capacité du modèle de culture à simuler les processus d'absorption d'azote du sol après la floraison. A partir d'une enquête auprès de 29 irrigants de blé dur, les pratiques et les stratégies de fertilisation azotée et d'irrigation, ainsi que les décisions stratégiques et tactiques ont été identifiées et formalisées dans un modèle de décision. Une évaluation de stratégies conçues sur la base des résultats d'enquêtes est proposée comme illustration de l'utilisation du modèle STICS adapté au blé dur et du modèle de décision formalisé. Le couplage informatique du modèle de culture STICS au modèle de décision permettra de disposer d'un modèle bio-décisionnel et ainsi pourra être utilisé pour concevoir et évaluer des stratégies de gestion conjointe de l'irrigation et de la fertilisation azotée du blé dur adaptées au contexte des exploitations agricoles / Changes in economic, regulatory and environmental context of agricultural production raise the need for research to evaluate and propose new strategies for joint management of irrigation and fertilization for durum wheat. The thesis had two objectives: i) adapting the simulation crop model STICS to different durum wheat cultivars, and ii) designing a decision model for nitrogen fertilization and irrigation practices. A database containing 373 experimental treatments carried out by INRA and ARVALIS before this PhD work was established and mobilized to conduct the adaptation and the evaluation of crop model. The adaptation of the crop model was first conducted through durum wheat parameter estimation by mathematical optimization. A comparative analysis of three approaches was conducted to select an appropriate approach to obtain an accurate and robust crop model for the simulation of grain yield, grain nitrogen content and intermediate variables (biomass, leaf area, amount of nitrogen absorbed) in different soil and climatic conditions. This study provided a methodological framework for crop models parameters estimation. The results of this study showed that the crop model, with its original formalism, was not sensitive to the effect of splitting of fertilization on the grain nitrogen content and protein concentration. The adaptation was then conducted through the modification of the formalism of nitrogen accumulation in grains by introducing a formalism inspired the AZODYN crop model. The modification did not significantly improve the model's sensitivity to the effect of N splitting on the nitrogen content of grain. The results of this study call into question the ability of crop model to simulate the absorption process of nitrogen after flowering. Unfortunately the lack of data concerning post-flowering leaf area dynmaics did not allow improving the model. From a survey of 29 irrigators, practices and strategies of nitrogen fertilization and irrigation, as well as strategic and tactical decisions have been identified and formalized in a decision model. An evaluation of strategies based on survey results is given as an illustration of the potential use of the STICS soil-crop model and the decision rules identified and formalised. The coupling of the crop model to the model decision will allow proposing and evaluating strategies adapted to the farm context for joint management of irrigation and nitrogen fertilization of durum wheat

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21835号 / 農博第2348号 / 新制||農||1068(附属図書館) / 学位論文||H31||N5207(農学部図書室) / 京都大学大学院農学研究科農学専攻 / (主査)教授 白岩 立彦, 教授 稲村 達也, 准教授 田中 朋之 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

The low and varying protein content and high crude fibre content of sunflower oil cake produced from sunflower seed create problems for the South African oil expelling industry. This prompted research into factors that may affect the seed quality for processing purposes. The seed quality characteristics are the seed oil and protein contents and the hullability. Analysis of the kernel-rich fraction produced after dehulling gives an indication of the potential oil yield, oil cake yield and oil cake protein and crude fibre contents and thus the processed value. Seed hullability and potential losses of oil and protein were affected by seed moisture content and seed size. Drying seed resulted in increased hullability, and sifting it into size classes proved to be a mechanism for differentiating in terms of oil cake quality. The effects of cultivar, environment and selected environmental variables on seed yield and processing quality were investigated by means of field trials. Seed yield and quality were more affected by environment than by cultivar. Seed size and hullability, and as a result also the protein content of the potential oil cake, were affected by plant population, with lower populations associated with better quality. Increased nitrogen application improved seed yield and seed protein content but lowered seed oil content, with no effect on hullability. Boron fertilisation improved seed yield in one trial but suppressed yield in a second trial. Hullability declined in one trial due to boron fertilisation. A mild water stress during the grain-filling stage reduced seed yield by 23% and hullability by 14%. Optimising the seed oil:seed protein ration through breeding may be the most advisable option for improving seed quality for processing. Due to the need for a seed grading system based on seed quality, regression analyses between easily measurable seed characteristics and seed quality parameters were done. The relatively low mean deviation between measured and predicted values indicate that seed oil content, protein content and hullability can be estimated with reasonable accuracy. These relationships must still be validated. / Dissertation (PhD (Plant Production: Agronomy))--University of Pretoria, 2002. / Plant Production and Soil Science / unrestricted

Rhizoctonia solani inoculum can be present either as soil- or tuber-borne sclerotia or hyphae. Although both inoculum sources play a role in disease development, it is not clear which of the two is more important. Successive cultivation of potato crops increases R. solani soil inoculum load resulting in an escalation in disease incidence and severity. The use of tolerant cultivars, however, can effectively reduce inoculum levels thereby decreasing disease intensity. Four pot trials were conducted; the objective of the first two pot trials was to determine the effect of tuber and soil-borne inoculum and stolon inoculations on disease development in sandy and clay loam soils. The second two pot trials were aimed at determining susceptibility levels of five cultivars. Two field trials were planted over two growing seasons in the same soils, using three inoculum levels. Results from the pot trials showed that tubers harvested from inoculated sandy soils developed significantly more disease than those harvested from clay loam soils. Of the three inoculum sources, stolon inoculation and seed-borne inoculum resulted in significantly more disease on progeny tubers than those from R. solani spiked soils. Although none of the cultivars proved to be tolerant to R. solani, BP1 was less susceptible to R. solani at temperatures between 21-26oC. More severe disease symptoms were observed under cooler temperatures on all cultivars. Results from the field trial showed the cultivation of potatoes in the same soil over two growing seasons resulted in an increase in diseased (black scurf) tubers. Furthermore, black scurf was most severe on tubers from soils infested with the highest concentration of inoculum. There were significant disease severity differences, with initial soil inoculum levels being directly proportional to final disease severity. Future studies in South Africa should focus on investigating the genetic composition of various cultivars; the effect of soil type and pH on the pathogenicity of R. solani and the use of molecular diagnostic tools to detect and quantify R. solani in soils. / Dissertation (MSc)--University of Pretoria, 2012. / Microbiology and Plant Pathology / unrestricted

Thesis (M. Agric. (Plant Protection)) -- University of Limpopo, 2019 / Damage and significant losses of potato cultivar due to Meloidogyne incognita has become a serious challenge, after the withdrawal of synthetic chemical nematicides due to their environment-unfriendliness. Various alternatives have been investigated each with a wide range of drawbacks. Most phytonematicides were highly phytotoxic to crops, while their effects on nematode suppression were highly variable. The use of Nemarioc-AG phytonematicide at pre- and post-emergence would help in determining the level that is effective in supressing M. incognita without being phytotoxic. The objective of this study was to determine whether Nemarioc-AG phytonematicide could serve as pre- and post-emergent phytonematicide without inducing phytotoxicity while suppressing population densities of M. incognita. For achieving this objective, treatments, namely, 0, 2, 4, 8 and 16 g of Nemarioc-AG phytonematicide, were arranged in a randomised complete block design (RCBD), with 7 replicates. Potato seed tubers were sown into 20 cm pots, Nemarioc-AG phytonematicide placed above the tubers and covered with soil, after initiation of treatments 5 000 eggs and second stage juveniles (J2) of M. incognita per plant were inoculated. For post-emergent, treatments, replications and design were the same as in pre-emergent. Potato seed tubers were sown and inoculated with 5000 eggs and second-stage juveniles (J2) of M. incognita per plant after 100% emergence. Nemarioc-AG phytonematicide were applied 7 days after inoculation. Trials were conducted in autumn (February-April) 2017 (Experiment 1) and repeated in autumn 2018 (Experiment 2). Plant growth variables and selected nutrient elements were collected and analysed using the Curve Fitting Allelochemical Response Data (CARD) model and lines of best fit, respectively. In pre-emergent application, Experiment 1, MCSP was established at 1.95 g, with the overall xii sensitivity (∑k) being equal to zero. Therefore, in Experiment 1 and Experiment 2, all nutrient elements to increasing concentration of Nemarioc-AG phytonematicide exhibited negative quadratic relations. In both Experiments, nematode variables over increasing concentration of Nemarioc-AG phytonematicide on potato exhibited negative quadratic relations, except in Experiment 1, where J2 in roots exhibited positive quadratic relations, with models ranging between 72 to 99%. In post emergent, Experiment 1, MCSP was established at 1.57 g, with the overall sensitivity (∑k) being equal to 2. In Experiment 1 and Experiment 2, nutrient elements over increasing concentration of Nemarioc-AG phytonematicide exhibited positive and negative quadratic relations, with models ranging from 89 to 97%. In Experiment 1, nematode variables over increasing concentration of Nemarioc-AG phytonematicide exhibited negative quadratic relations, with models ranging between 92 and 98%. Positive and negative relations suggested that the product stimulated and inhibited plant growth or accumulation of selected essential nutrient elements, respectively. Increasing concentration of Nemarioc-AG phytonematicide had stimulated certain plant variables and inhibited population densities of M. incognita in pre- and post emergent application; therefore, this product was suitable for use as pre- and post emergent in management of nematodes on the test crop.