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Today, the livestock sector accounts for 18 % of greenhouse gas emissions. To prevent negative environmental effects, dietary changes are required. Locally cultivated legumes with high protein content can be used in order to produce plant-based protein, which can replace animal-based protein. In Sweden, pea (Pisum sativum L.) has been cultivated for centuries and been a valuable protein source for both human consumption and animal feed. VicJ, a gene in pea, has previously been associated with variation in protein content. In the present study, a primarily Swedish material of 31 accessions from different improvement stages were analysed for differences in protein content. It was also tested if genetic variation of VicJ was associated with variation in protein content. The result showed no differences in protein content between various improvement stages, which indicated that selection on the trait has not occurred. No genetic variation associated with variation in protein content in VicJ was detected either. However a stop codon in VicJ, known to be associated with reduced protein content was missing in the material, suggesting that the accessions studied may be suitable for breeding to increase protein content in pea.

Submitted by Jaine Aparecida de Camargo Dias Dias (inecamargo_agr@hotmail.com) on 2017-04-11T19:52:39Z No. of bitstreams: 1 jaine - Tese corrigida 03-04-2017prontoooo.pdf: 1143866 bytes, checksum: 9fa67396aff6d567d35e24c7086142ad (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-04-17T19:31:57Z (GMT) No. of bitstreams: 1 dias_jac_dr_ilha.pdf: 1143866 bytes, checksum: 9fa67396aff6d567d35e24c7086142ad (MD5) / Made available in DSpace on 2017-04-17T19:31:57Z (GMT). No. of bitstreams: 1 dias_jac_dr_ilha.pdf: 1143866 bytes, checksum: 9fa67396aff6d567d35e24c7086142ad (MD5) Previous issue date: 2017-03-02 / A utilização de sementes ricas em molibdênio se constitui numa técnica promissora para sanar as deficiências desse micronutriente, o qual é importante para a fixação biológica do nitrogênio e metabolismo vegetal. O objetivo desse trabalho foi avaliar a produtividade das plantas, o teor de molibdênio e a qualidade fisiológica das sementes em resposta às fontes, doses e épocas de aplicação foliar de molibdênio, bem como, o grau de nodulação das plantas originadas de sementes enriquecidas com molibdênio. Para tanto, foi conduzido um experimento na área experimental da Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia/UNESP – Campus de Ilha Solteira, situada no município de Selvíria - MS, no período de outono e inverno de 2015 e de 2016. O delineamento experimental utilizado nessa fase foi em blocos casualizados com os tratamentos distribuídos no arranjo fatorial 2 x 5 x 2 (duas fontes de molibdênio (molibdato de amônio com 81% de Mo e produto Geoclean com 15 % de Mo), cinco doses de Mo (0, 300, 600, 900 e 1.500 g ha-1) e duas épocas de aplicação (V4.6 e R1)), totalizando 20 tratamentos com quatro repetições. Foram avaliadas o número de vagens por planta, número de sementes por planta, número de sementes por vagem, massa de 100 sementes e a produtividade de grãos. Posteriormente, foram avaliados a qualidade fisiológica (germinação e vigor) e nutricional (teor de proteínas e molibdênio) das sementes colhidas, assim como, o potencial de formação de nódulos das plantas originadas por sementes, enriquecidas por molibdênio na fase de campo. Para averiguar a qualidade fisiológica, o delineamento foi o inteiramente casualizado, com os mesmos 20 tratamentos e 4 repetições. Ainda, foram avaliados o teor de molibdênio nas sementes, qualidade nutricional e teores de macronutrientes. Na investigação do potencial de nodulação, o experimento foi conduzido sob condições de casa de vegetação, em delineamento inteiramente casualizado com os 20 tratamentos, com as sementes obtidas da fase de campo, sendo inoculadas e semeadas em caixas plásticas contendo composto orgânico, semeando-se 20 sementes por caixa. Concluiu-se que as doses crescentes de molibdênio proporcionaram o enriquecimento do nutriente nas sementes de ervilha. A aplicação de molibdênio em ervilha deve ser efetuada no estádio R1. O produto Geoclean proporcionou maior acúmulo do nutriente, assim como, interferiu de forma positiva para a maioria dos atributos referentes à qualidade fisiológica das sementes de ervilha. A aplicação de molibdênio não promoveu aumento na produtividade de sementes de ervilha. O uso de sementes enriquecidas com Mo não favoreceu o processo de nodulação da ervilha. / The use of molybdenum-rich seeds constitutes a promising technique to remedy the deficiencies of this micronutrient, which is important for biological nitrogen fixation and plant metabolism. The objective of this work was to evaluate the plant productivity, molybdenum content and physiological quality of seeds in response to molybdenum foliar application, doses and times, as well as the degree of nodulation of the plants originated from seeds enriched with molybdenum. For that, an experiment was carried out in the experimental area of the Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia/UNESP – Campus de Ilha Solteira, located in the country de Selvíria, MS, during the autumn and winter of 2015 and 2016. The experimental design used in this phase was randomized blocks with treatments distributed in the factorial arrangement 2 x 5 x 2 (two sources of molybdenum (ammonium molybdate with 81% Mo and Geoclean product with 15% Mo), five doses of Mo (0, 300, 600, 900 and 1,500 g ha-1) and two application times (V4.6 and R1), totaling 20 treatments with four replicates. The number of pods per plant, number of seeds per plant, number of seeds per pod, mass of 100 seeds and grain yield were evaluated. Afterwards, the physiological (germination and vigor) and nutritional quality (protein and molybdenum content) of the harvested seeds were evaluated, as well as the potential for nodule formation of seedlings enriched by molybdenum in the field phase. To determine the physiological quality, the design was completely randomized, with the same 20 treatments and 4 replicates. Also, the molybdenum content in the seeds, nutritional quality and macronutrient contents were evaluated. In the investigation of nodulation potential, the experiment was conducted under greenhouse conditions, in a completely randomized design with the 20 treatments, with the seeds obtained from the field phase, being inoculated and seeded in plastic boxes containing organic compound, 20 seeds per carton. It was concluded that increasing doses of molybdenum provided nutrient enrichment in pea seeds. The application of molybdenum to pea must be carried out at stage R1. The product Geoclean provided greater accumulation of the nutrient, as well as, it interfered in a positive way for most of the attributes related to the physiological quality of the pea seeds. The application of molybdenum did not promote increase in pea seed productivity. The use of seeds enriched with Mo did not favor the process of nodulation of the pea.

Orientador: Cibele Chalita Martins / Banca: João Nakagawa / Banca: Marco Eustáqui de Sá / Banca: Leila Martins / Banca: Denise Garcia de Santana / Resumo: A qualidade da semente na produção agrícola é um dos principais fatores a ser considerado na implantação da cultura, havendo consenso sobre a importância da germinação, do vigor das sementes e da necessidade de avaliá-los. O trabalho teve como objetivo estabelecer metodologias para os testes de germinação e vigor com ênfase no teste de condutividade elétrica para a avaliação da qualidade fisiológica de sementes de ervilha forrageira (Pisum sativum subsp. arvense). Para estabelecer a metodologia do teste de germinação utilizou-se quatro lotes sendo dois da cultivar IAPAR 83 e dois da BRS Forrageira. Foram testadas cinco temperaturas (15ºC, 20ºC, 25ºC, 20-30ºC e 15-25ºC) e dois substratos (areia e papel). Para a metodologia para o teste de condutividade elétrica foram utilizados dez lotes da cultivar IAPAR 83. Foram realizados os testes de germinação, primeira contagem de germinação, emergência de plântulas em casa de vegetação para caracterização dos lotes e estudos específicos para os testes de condutividade elétrica (temperaturas de 20ºC e 25ºC, volumes de 75mL e 250mL de água, 50 sementes, e períodos de 8, 16, 20, 24 e 28 horas). Concluiu-se que o teste de germinação para ervilha forrageira deve ser conduzido a 20ºC em rolo de papel com primeira contagem e contagem final ao 4º e 7º dia, respectivamente. O teste de condutividade elétrica utilizando 50 sementes embebidas em 250 mL de água, na temperatura de 25ºC por 24 horas mostrou-se promissor para a diferenciação de lotes de sementes de ervilha forrageira / Abstract: Seed quality is an important role in the establishment of crops. It is consensual that seed germination and vigor are important tools for the production process and must be evaluated. The present research had as objective to establish methodologies for the germination and electrical conductivity tests to evaluate physiological quality of forage pea seeds (Pisum sativum subsp. arvense). Two lots of the cultivar „IAPAR 83‟ and two lots of the cultivar „BRS Forrageira‟ were used to establish the methods for the germination test. Five temperatures (15ºC, 20ºC, 25ºC, 20-30ºC and 15-25ºC) and two substrates (between sand and rolled paper towel) were tested. Ten lots of the cultivar „IAPAR 83‟ were studied to establish the methodology for the electrical conductivity test. Germination, first count of germination and seedling emergence in greenhouse were studied. For the electrical conductivity test, different temperatures (20ºC and 25ºC), water volumes (75 mL and 250 mL) and imbibition periods (8, 16, 20, 24 and 28 hours) were evaluated. It was concluded that the germination test for forage pea seeds must be carried out under 20ºC and in rolled paper towels with first counting and final counting to the 4 and 10 days after sowing, respectively. The electrical conductivity test is sensitive to differentiate seedlots of forage pea whenever conducted with 50 seeds imbibed in 250 mL of water under 25ºC for 24 hours / Doutor

As global meat consumption is rising, the negative impact the animal husbandry sector has on the environment will increase. Greenhouse gas emissions have increased by 40 % during the last 200 years, and the animal husbandry sector is today responsible for 18 % of the total greenhouse gas emissions from food production. More environmentally friendly protein sources, such as soy and pea, must therefore be developed. Pisum sativum can (unlike the most popular meat alternative – soy) be grown all over Europe and might thus be a good alternative that allows for locally sourced alternatives to meat protein. Identifying genes with important agricultural properties might aid the development of pea cultivars with a more reliable protein content. One such gene was hypothesised to be the OMT gene, which is strongly expressed during the embryonic development of P. sativum and seems involved in functions such as seed storage and protein synthesis. Thirty-one accessions of P. sativum were tested to see if different improvement types differed from each other regarding protein content and seed weight, but no such differences were found. DNA was extracted from all accessions, sequenced, and successful sequences were tested to determine if variation in the gene correlated with protein content. Two haplotypes were identified, but there was no correlation between them and protein content found. Based on the results of this study, there is little evidence that the OMT gene correlates with protein content in the studied accessions.

Green garden peas (Pisum sativum L.) are a popular vegetable used in meal preparation worldwide. Green peas are commonly available in their frozen form due to their short growing season. Green peas are easily susceptible to changes in the field, immediately after harvest, during processing and storage, and thereforerequire careful handling to maintain good quality. The acceptability of frozen green peas is greatly dependent on the sensory quality. Descriptive sensory profiles and physico-chemical properties of frozen green peas can be investigated and used to assess and explain product quality. Six brands of frozen green peas representing product sold for retail and caterer's markets were purchased and subjected to descriptive sensory evaluation, physico-chemical analyses and quality grading. Four batches with different best before dates were purchased for each brand. Quality grading was done using statutory standards and a selected company protocol. Dry matter content, alcohol insoluble solids content, starch content, °Brix, residual peroxidase activity, size sorting, hardness using texture analysis and colour measurements were carried out for physico-chemical analyses. Generally, retail class peas were of superior sensory quality to caterer's peas although one caterer's brand had quality traits that were more comparable with the retail brands than the other caterer's brands. Quality grading revealed that frozen green peas can be downgraded due to poor colour, presence of extraneous vegetable matter, presence of sandy grits and soil stains, poor flavour and poor texture. Downgrading of peas can be due to one reason or due to a combination of two or more poor quality characteristics. Good quality peas were described as sweeter, smaller, greener, more moist and more tender than the poorer quality peas usingdescriptive sensory evaluation. Good peas also had high °Brix content, more intense green colour, low starch, alcohol insoluble solids, dry matter contents and texture hardness measured. Quality grading revealed that flavour problems were the major cause for low graded samples. Sensory evaluation and the methods used for instrumental analyses however, showed more easily the variations in texture attributes than flavour attributes of peas. Poor flavour was probably caused by ineffective blanching, low soluble solids content which enhanced the perception of bitterness and the presence of acetone notes. Poorly coloured peas were also either underblanched or had low moisture contents. Mealiness and hardness in peas were explained by high starch, alcohol insoluble solids and dry matter contents. Instrumental texture analysis showed indications that the harder peas also had tougher skins in addition to harder cotyledons. Lower peas also displayed characteristics typical of delayed harvesting and post-processing temperature abuse such as dehydration and pale green/white colouration. The sensory quality of frozen green peas can be predicted from the physico-chemical methods of analysis used in this study. Some of the frozen peas on sale are below the acceptable standards of quality. To achieve good frozen pea quality it is important to put emphasis on maturity at harvest and post processing storage conditions (store at -18 °C or lower and avoidfluctuatingtemperatures). The use of a strict quality grading scheme has been shownto result in good quality frozen peas. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Food Science / unrestricted

Submitted by Amauri Alves (amauri.alves@ufv.br) on 2015-11-05T15:19:50Z No. of bitstreams: 1 texto completo.pdf: 1256591 bytes, checksum: 7fb1f90875c23ff0319fba481041b6af (MD5) / Made available in DSpace on 2015-11-05T15:19:50Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1256591 bytes, checksum: 7fb1f90875c23ff0319fba481041b6af (MD5) Previous issue date: 2013-08-21 / A aplicação de ON em sementes tem se mostrado promissora, uma vez que as sementes em contato com a solução de nitroprussiato de sódio (SNP), doador de ON, em geral, germinam mais e com maior velocidade, tolerando melhor tanto estresses abióticos como a deterioração natural ocasionada pelo armazenamento. Assim, na presente pesquisa, teve-se como objetivo avaliar as principais alterações que ocorrem na durante a germinação de sementes de ervilha devido à aplicação do ON. Para tanto, foram conduzidos dois experimentos. No primeiro experimento, três lotes de sementes de ervilha com diferentes níveis de qualidade fisiológica foram semeados em substrato umedecido com água (controle) ou com solução de SNP (50 μM). Adotou-se o delineamento inteiramente casualizado, com quatro repetições. Os dados foram submetidos à análise de variância e as médias foram analisadas pelo teste F a 5% de probabilidade. No segundo experimento, sementes de ervilha foram semeadas em substrato umedecido com água (controle), solução de polietilenoglicol [PEG 6000 (-0,15 MPa)] e solução de PEG 6000 + SNP (-0,15 MPa; 50 μM). O delineamento estatístico adotado foi inteiramente casualizado com quatro repetições. Os dados foram submetidos a análise de variância e as médias foram analisadas pelo teste Tukey a 5% de probabilidade. Conclui-se que o ON não aumenta a germinação das sementes de ervilha, entretanto há aumento no vigor. Sementes com menor potencial fisiológico respondem melhor à aplicação do ON. O estresse hídrico diminui a germinação e o vigor das sementes de ervilha e causa desbalanço das espécies reativas de oxigênio. A aplicação do SNP promoveu maior germinação e maior velocidade de germinação em sementes sob estresse hídrico. Houve maior atividade das amilases, das enzimas antioxidativas e menor conteúdo de H 2 O 2 , menor liberação de O 2- e menor peroxidação de lipídeos em sementes tratadas com doadores de ON. / The NO application in seeds has shown promising, because the seeds in contact with the sodium nitroprusside (SNP) solution, NO donor, usually germinates more and faster and are more tolerant to abiotic stresses such as natural deterioration caused by storage. Thus, it is interesting to know how the NO acts on the seeds germination to improve the early seedling development. Therefore, the research aimed to evaluate the main changes that occur during the germination of pea seeds due the NO application. Therefore, two experiments were conducted. In the first one, three lots of pea seeds with different physiological potential levels were sown in a substrate with water (control) or with SNP solution (50 μM). It was adopted the completely randomized design with four replications. The data were subjected to variance analysis and the means were analyzed by F test at 5% of probability. In the second experiment, pea seeds were sown in a substrate with water (control), polietilenoglicol [PEG 6000 solution (-0,15 MPa)] and PEG 6000 + SNP solution (-0,15 MPa; 50 μM). It was adopted the completely randomized design with four replications. The data were subjected to variance analysis and the means were analyzed by Tukey test at 5% of probability. To conclude, the NO does not increase the germination of pea seeds, but increase the seeds vigor. Seeds with lower physiological potential gives a better response to the NO application. Water stress decrease the germination and vigor of pea seeds and cause reactive oxygen species imbalance. The SNP application promoted a higher and faster germination in seeds under water stress. There were higher activity of the amylases, higher activity of the antioxidative enzymes, less H 2 O 2 content, less O 2- liberation and consequently less lipid peroxidation in seeds treated with NO.

A busca por embalagens flexíveis rapidamente degradáveis tem sido intensa nos anos mais recentes. Amidos de variadas fontes têm sido avaliados para a produção de filmes, sendo que a maioria destes apresenta boas características mecânicas e de barreira ao oxigênio, entretanto, uma série de limitações é observada com relação às suas características hidrofílicas e permeabilidade ao vapor d´água. O amido de ervilha normalmente apresenta teores mais elevados de amilose, o que pode melhorar a obtenção da rede formadora de filmes. Além disto, as associações amido-goma podem modificar a gelatinização e retrogradação do amido, processos que interferem na formação de filmes. O acréscimo de plastificantes também tem se mostrado de importância para melhorar as propriedades mecânicas dos filmes. Assim, o objetivo do presente trabalho foi avaliar o efeito da adição de goma xantana e de glicerol ao amido de ervilha verde de alto teor de amilose (cv. Utrillo) na elaboração de filmes e em suas características. Soluções filmogênicas (SF) com diferentes teores de amido de ervilha (3, 4 e 5%), de goma xantana (0, 0,05 e 0,1%) e de glicerol (proporção glicerol-amido de 1:5 p/p) foram estudadas. As SF foram obtidas por ebulição (5 min.), seguida de autoclavagem por 1h. a 120°C. Os filmes foram prepa rados segundo a técnica de casting. O aumento da concentração de amido na solução filmogênica aumentou a espessura, fator de ruptura, resistência à perfuração e solubilidade dos filmes em água. O aumento da concentração da goma xantana interferiu apenas nas propriedades associadas à cor dos filmes, aumentando os valores da tonalidade e decrescendo o croma a* e a transparência. O aumento da concentração do glicerol interferiu nas propriedades mecânicas dos filmes, gerando redução dos valores de resistência máxima à tração, tensão na ruptura, resistência à perfuração e fator de ruptura. O plastificante também gerou aumento do alongamento na ruptura, redução da transparência e aumento da espessura e da solubilidade do filme em água. / In the past few years, the attempt to obtain degradable flexible packaging has increased considerably. In this sense, starches obtained from different botanical sources have been evaluated to produce films. Most of these films present good mechanical characteristics and provide a good barrier to oxygen. Nevertheless, some limitations have been observed in relation to their hydrophilic properties and permeability to water vapor. Studies using starch from green peas with high levels of amylose to produce films were not found in the literature. The higher levels of amylose can improve the achievement of the matrix that forms films. In addition, starch-gum associations can modify starch gelatinization and retrogradation, processes which interfere with film formation. The addition of plasticizers has also been considered important to improve the mechanical properties of films. The aim of this study was to evaluate the effect of the addition of xanthan gum and glycerol to the starch of green peas with high content of amylose (cv. Utrillo) in the preparation of films and in their features. Filmogenic solution (FS) with different levels of pea starch (3, 4 and 5%), xanthan gum (0, 0.05 and 0.1%) and glycerol (glycerol-starch ratio of 1:5 p/p) were tested. The FS was obtained by boiling (5 min.), followed by autoclaving for 1h. at 120°C. The films were prepared by casting. The increased concentration of starch in the solution increased the thickness, factor of rupture, puncture force and solubility of films in water. Increasing amounts of xanthan affected only the properties associated with the color of the films, increasing the values of hue angle and decreasing the chroma a* and transparency. The increased concentration of glycerol interfered in the mechanical properties of the films, causing reduction of the maximum values of tensile strength, strain at break, puncture force and factor of rupture. The plasticizer also caused an increase of elongation at break, reduced transparency and increased thickness of the film and the solubility in water.

Les pucerons sont parmi les principaux ravageurs des cultures dans les régions tempérées. Leur succès comme parasites de plantes repose sur leur fort potentiel reproductif dû à la parthénogénèse durant le printemps et l'été ainsi qu’à la symbiose avec Buchnera aphidicola. Cette bactérie symbiotique obligatoire fournit aux pucerons les acides aminés essentiels qui sont déficients dans leur alimentation déséquilibrée (la sève élaborée des plantes), et contribue ainsi à leur développement et reproduction. Le premier volet de ce travail de thèse a consisté à déterminer les besoins en acides aminés des différents stades embryonnaires, afin d’identifier des facteurs clé de l’association symbiotique au cours du développement du puceron du pois Acyrthosiphon pisum. Cette étude, conduite sur des embryons prélevés in vivo ou mis en culture in vitro, a révélé i) des exigences métaboliques évoluant au cours de développement du puceron, ii) une dépendance au compartiment maternel pour l’approvisionnement des embryons en acides aminés, et iii) de forts besoins en acides aminés aromatiques, notamment en tyrosine, pour les stades embryonnaires tardifs et le premier stade larvaire précoce. Le deuxième volet de cette thèse a alors eu pour objectif l’identification de gènes cibles à l’intérieur des voies révélées par l’approche métabolique. A l’aide d’une puce à ADN dédiée au génome du d’A. pisum, les profils d’expression des gènes du puceron ont été analysés au cours de son développement embryonnaire. L’analyse fonctionnelle des différents groupes de gènes montre que ceux liés au métabolisme des acides aminés présentent de hauts niveaux d’expression et des variations significatives entre les différents stades. La voie métabolique des acides aminés aromatiques et tout particulièrement les gènes menant à la synthèse de la tyrosine, ainsi que les gènes/voies liés à la formation et à la maturation de la cuticule, sont parmi les plus sollicités chez les embryons tardifs. L’ensemble des résultats obtenus par les approches métabolique et transcriptomique suggère une synthèse et une accumulation de tyrosine au cours du développement embryonnaire, en vue de son utilisation comme précurseur pour la sclérotisation et le tannage cuticulaire après la ponte. Le dernier volet de ce travail de thèse a consisté en une analyse fonctionnelle du rôle du gène ACYPI007803, codant l’enzyme catalysant la synthèse de la tyrosine à partir de la phénylalanine, par la technique d’ARN interférence (RNAi). Une augmentation de la mortalité des larves pondues par les femelles traitées est corrélée à la diminution de l’expression du gène cible dans les compartiments symbiotiques (les chaines embryonnaires et les bactériocytes maternels) et confirme le rôle clé du gène ACYPI007803 dans le développement des embryons chez le puceron du pois. / Aphids are among the main crop pests in temperate regions. Their success as parasites of plants is based on their strong reproductive output due to parthenogenetic reproduction during spring and summer and to their symbiosis with Buchnera aphidicola. This obligatory symbiotic bacterium supplies aphids with essential amino acids poorly available in their unbalanced food (the phloem sap of plants), and so contributes to their development and reproduction. The first part of this work consisted in determining amino acid needs of different embryonic stages, in order to identify key factors of the symbiotic association during the pea aphid development. This study, led on embryos taken in vivo or cultivated in vitro in culture media, allowed us to identify: i) the evolution of metabolic requirements of embryos during development, ii) a dependence of embryos from the maternal compartment for their supply in amino acids, and iii) strong needs in aromatic amino acids, particularly in tyrosine, of the late embryonic stages and the early first larval stage of the pea aphid. The second part of this thesis had for objective the identification of key genes inside pathways revealed by the metabolic approach. Using a dedicated oligonucleotides microarray, the gene expression profiles of the aphid were analysed during the development of the insect. The functional analysis of different gene groups showed that genes involved in amino acids metabolism are globally over-expressed, but they also showed significant transcriptional regulations in the switches between the different stages studied here. The metabolic pathway of aromatic amino acids and particularly the genes involved in the biosynthesis of tyrosine, as well as genes / pathways involved in the formation and the maturation of the cuticle, were among the most solicited in the late embryos. These transcriptomic results, taken together with those obtained by the metabolic approach, suggest that the amino acid tyrosine is synthesized and accumulated by the pea aphid during its embryonic development, in order to later be used as precursor for the sclerotization and the cuticular tanning, processes that occur after insect laying. The last part of this work consisted in a functional analysis of the gene ACYPI007803, coding the enzyme catalysing the tyrosine synthesis from the phenylalanine, by using the RNA interference (RNAi) technique. An increase of the mortality of larvae laid by the treated females was correlated with the decrease of the expression of the target gene in the symbiotic compartments (the embryonic fraction and the maternal bacteriocytes) so confirming the key role of the ACYPI007803 gene in the development of the pea aphid embryos.