Manual da safra e contra safra do olival

O manual da safra e contra safra do olival é dirigido de forma particular a agricultores e técnicos da região de Trás-os-Montes e de outras zonas do país onde se mantenha interesse no olival tradicional de sequeiro. A rega, contudo, não foi esquecida, sendo vista como uma das poucas alternativas à revitalização do sector. O olival de sequeiro encontra-se hoje no limiar da viabilidade técnica e económica. Devido às condições marginais em que é cultivado, e a uma técnica cultural normalmente de qualidade insatisfatória, é nestes olivais que o fenómeno da safra e contra safra se torna mais evidente. Trás-os-Montes é uma região economicamente deprimida onde as pequenas aldeias têm perdido população a ritmo acelerado. Poucas freguesias mantêm ainda escola primária, devido à reduzida natalidade. Poucos são os jovens que projectam o seu futuro e o das suas famílias baseado na actividade agrícola. O interior do país nunca desenvolveu actividade económica relevante fora do sector agrícola. A actividade industrial é ténue. As cidades de maior dimensão como Vila Real, Bragança, Chaves e Mirandela têm resistido à perda de população nas sedes de concelho devido a algum investimento público (ensino superior, saúde, …) que assegura poder de compra às populações e permite o aparecimento de pequenas empresas de dimensão regional (construção, restauração, serviços, …). As vias de comunicação que lentamente foram sendo construídas nunca foram estímulo suficiente para cativar investimento industrial significativo para a região. O olival de sequeiro mantém ainda hoje importância social e económica determinante na região, sendo a olivicultura das poucas actividades em meio rural com capacidade para gerar rendimento e contribuir para a fixação da população. Os decisores políticos e as autoridades locais devem ter presente que todos os esforços devem ser feitos para manter estes sistemas em produção. É necessário ter a noção de que não há condições realistas para, a curto prazo/ médio prazo, se modificar a estrutura produtiva do olival. Os sistemas de plantação que actualmente se utilizam noutras regiões, designadamente os olivais de alta densidade (494) a 865 árvores/ha) e os super-intensivos (1482 a 2223 árvores/ha), necessitam de parcelas de terreno com área e fertilidade adequadas. Necessitam também de água para rega e que as explorações estejam electrificadas. Em Trás-os-Montes não há, actualmente, água armazenada para regar áreas relevantes de olival e a electrificação é um problema adicional devido à dispersão das parcelas. O declive dos terrenos é ainda um constrangimento suplementar. Tudo indica que a estrutura fundiária da região, com a propriedade pulverizada em pequenas parcelas, associada a dificuldades na electrificação dessas parcelas, disponibilidade limitada de água para rega, inclinação dos terrenos e idade avançada dos olivicultores vá atrasar a reestruturação do olival. É nossa convicção que nos próximos 10 anos o cenário da olivicultura em Trás-os-Montes não apresentará modificações de monta, excepcionando-se provavelmente o incremento da colheita mecanizada e um provável, mas ligeiro, aumento da área de regadio. Esperemos que a maior modificação não consista no abandono da actividade por parte de muitos produtores. É necessário lutar pela viabilidade do olival actual, mantendo presente a necessidade de o modernizar com a urgência possível. É necessário criar pressão política para que surjam infra-estruturas de regadio e para que os programas de apoio ao sector se mantenham ou sejam reforçados. Olivicultores, técnicos, associações de produtores, autarquias e decisores políticos devem unir esforços em torno daquela que é a principal actividade económica de muitas freguesias da região

Long-term studies on ground management in rainfed olive orchards

Two decades of research on soil management in rainfed olive graves, encompassing four experimental ftelds, one of which took eighteen years of continuous assessment, allowed comparative evaluation of severa! treatments including conventional tillage, residual herbicides, post-emergence herbicides, covers of natural vegetation (fertilized and unfertilized), sown covers managed as green manures and incorporated into the soil, or shredded and kept in the ground as a mulch, and sown covers of self-reseeding pasture legumes. This series of studies allowed showing that a better contrai of the herbaceous vegetation improves olive growth and yield and a greater development of the herbaceous vegetation improves severa! indicators of the soil fertility, which creates a great ambiguity. However, a large set of advantages comes from the use of early-season self-reseeding annual legumes. These plants presenta very short growing cycle and develop asynchronously with the trees (in winter, during the resting period of olive), showing reduced competition for water, allowing high productivity even in rainfed conditions. Additionally, they protect the soil from erosion ali year round, with live vegetation during winter anda mulch of dead vegetation during the summer, improve soil fertility, including the increase of soil organic matter, and are able to ftx nitrogen improving the nitrogen nutritional state of the trees.info:eu-repo/semantics/publishedVersio

Phylogeny, distribution and pathogenicity of Lasiodiplodia species associated with dieback of table grape in the main Brazilian exporting region

[EN] Botryosphaeria dieback is an important disease of table grape in the Sao Francisco Valley, the main Brazilian exporting region. The objectives of this study were to identify species of Lasiodiplodia associated with botryosphaeria dieback of table grapes in the Sao Francisco Valley, investigate the prevalence and distribution of the species in the region, and evaluate their pathogenicity and virulence in green shoots of table grape. A total of 112 Lasiodiplodia isolates were obtained from 14 vineyards, located in Casa Nova, Juazeiro and Petrolina. Fungal identifications were made using phylogenetic analysis based on partial sequences of translation elongation factor 1-alpha (EF1-alpha) and internal transcribed spacer (ITS) sequences, in combination with morphometric characteristics of conidia. Eight species of Lasiodiplodia were identified: L. brasiliense, L. crassispora, L. egyptiacae, L. euphorbicola, L. hormozganensis, L. jatrophicola, L. pseudotheobromae and L. theobromae. Except for L. crassispora, L. pseudotheobromae and L. theobromae, all the other species are reported for the first time on grapevine worldwide. The distribution of Lasiodiplodia species differed between the three table grape populations of Sao Francisco Valley. All Lasiodiplodia species isolated in this study were present in the population of Casa Nova and Lasiodiplodia theobromae was the most prevalent. All species of Lasiodiplodia were pathogenic on detached green shoots of grapevine, with L. brasiliense being the most virulent.This study was financed by Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco (FACEPE APQ 137-5.01/12, IBPG-0674-5.01/09). M.P.S.C. and S.J.M. also acknowledge the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq research fellowship. A.J.L.P. thanks Fundacao para a Ciencia e a Tecnologia (Portugal) for financial support through grant PEst-OE/BIA/UI0457/2011.Correia, KC.; Silva, M.; De Morais, M.; Armengol Fortí, J.; Phillips, A.; Camara, M.; Michereff, S. (2016). Phylogeny, distribution and pathogenicity of Lasiodiplodia species associated with dieback of table grape in the main Brazilian exporting region. Plant Pathology. 65(1):92-103. doi:10.1111/ppa.12388S9210365

Alterações climáticas e degradação do solo no interior de Portugal: um cocktail explosivo para as culturas perenes

A agricultura é uma fonte importante de emissões de gases com efeito de estufa, contribuindo fortemente para as alterações climáticas e, ao mesmo tempo, é um dos setores económicos mais afetados, particularmente devido à modificação dos padrões de precipitação e temperatura. Sendo as regiões com clima mediterrânico "pontos quentes" das alterações climáticas, são esperados efeitos negativos nas culturas perenes no interior de Portugal, especialmente sob regime de sequeiro. Ao mesmo tempo, assistimos à degradação do solo, fenómeno que potencia as causas e as consequências das alterações climáticcas nas culturas. Neste artigo apresentamos uma visão crítica das duas grandes ameaças ambientais e socioeconómicas e deixamos em aberto possíveis soluções, de forma a minimizar os impactes da mudança no clima e a preservar para as gerações futuras este recurso natural, limitado e não renovável a curto prazo."Novas práticas em olivais de sequeiro: estratégias de mitigação e adaptação às alterações climáticas'; com a referência PDR2020-101-032119, e "EGIS: Estratégias para uma gestão integrada do solo e da água em espécies produtoras de frutos secos'; com a referência PDR2020-101-030994, financiados pelo Fundo Europeu Agrícola de Desenvolvimento Rural (FEADER) e pelo Estado Português no âmbito da Ação 1.1 >, integrada na Medida 1. <<Inovação» do PDR 2020 -Programa de Desenvolvimento Rural do Continente; Projeto INNOVINE&WINE (NORTE-01-0145-FEDER- 000038), cofinanciado pelo Fundo Europeu de Desenvolvimento Regional (FEDER) através do programa NORTE 2020.info:eu-repo/semantics/publishedVersio

Olive response to potassium applications under different water regimes and cultivars

Although potassium (K) is a macronutrient few studies have evaluated the response of olive tree to K fertilization. In this work results of two field and two pot K fertilizer experiments are presented. One of the field trials was conducted in a commercial young olive grove. The second was conducted in a plantation purposely established for this study. In the two fieldand thefirst potexperiment,theK supply was the single variation factor. The second pot experiment was arranged as a factorial with two K rates, two water regimes and two cultivars (‘Arbequina’ and ‘Cobranc¸osa’). K supply did not increase olive tree growth or yield. Accumulated olive yield in the first field experiment, for instance, varied from 2.46 and 2.84 kg tree-1, respectively in K treated and untreated plants. K supply increased the shoot/root ratio (1.6–2.0 from the control to the most fertilized treatment) and the concentration of K in roots (2.9–11.2 g kg-1) to a greater extent than in leaves (7.0–11.9 g kg-1), suggesting that shoots are a priority sink for K and roots may store the nutrient as a reserve. Plant water status and chlorophyll a fluorescence were not significantly affected by K applications. Plants suffering from water stress yielded less phytomass (40.2–56.4 g pot-1, respectively in control and well-watered plants) and showed higher K concentrations in leaves (14.2–11.6 g kg-1) and lower in roots (4.9–6.8 g kg-1) which is probably due to the reduction of K uptake from the dry soil. ‘Cobranc¸osa’ appeared to be more tolerant to water stress than ‘Arbequina’. These experiments showed a poor response of olive tree to K fertilization. Considering that K is usually applied by farmers every year, it seems that further studies on K fertilizationin olive are needed in order to adjust K fertilizer rates to crop needs.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013). The work was also funded by the INTERACT Project—‘‘Integrative Research in Environment, Agro-Chains and Technology’’, No. NORTE- 01-0145-FEDER-000017, in its line of research entitled ISAC, co-financed by the European Regional Development Fund (ERDF) through NORTE 2020 (North Regional Operational Program 2014/2020). For authors integrated in the CITAB research centre, it was further financed by the FEDER/ COMPETE/POCI—Operational Competitiveness and Internationalization Programme, under Project POCI-01-0145- FEDER-006958, and by National Funds of FCT–Portuguese Foundation for Science and Technology, under the Project UID/ AGR/04033/2013.info:eu-repo/semantics/publishedVersio

Olive tree response to applied phosphorus in field and pot experiments

Phosphorus (P) application in olive orchards is very common in the Mediterranean basin although experimental evidence of crop response to applied P is practically non-existent. In this work soil P and tree P nutritional status of the olive groves of NE Portugal were assessed from a population of 1808 soil and 2252 leaf samples. Plant response to applied P was evaluated from two field and two pot experiments carried out with the cultivar ‘Cobrançosa’. The analyses of soil and leaf samples of the olive orchards of the region indicate that P fertilizer recommendations should be based on leaf rather than on soil analyzes, since the latter seems to overestimate the need for P. The field and pot experiments hardly showed any positive response to P applications, which is a sign that the use of P fertilizer in olive can be substantially reduced. Nonetheless, in one pot experiment, P application significantly increased total dry matter yield during three consecutive years, in a strict association with higher tissue P concentrations and enhanced photosynthetic activity, as revealed by gas exchange and chlorophyll fluorescence traits. The experimental results also showed that the roots can uptake and store P when available in the soil, which may buffer the levels of P in the shoots. The acid phosphate activity can provide useful information but deserves caution in the interpretation of results since it depends not only on the availability of inorganic P in the soil, but also on the available organic substrate and pH.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013). The work was also funded by the INTERACT project – “Integrative Research in Environment, Agro-Chains and Technology”, no. NORTE-01-0145- FEDER-000017, in its line of research entitled ISAC, co-financed by the European Regional Development Fund (ERDF) through NORTE 2020 (North Regional Operational Program 2014/2020). For authors integrated in the CITAB research centre, it was further financed by the FEDER/COMPETE/POCI – Operational Competitiveness and Internationalization Programme, under Project POCI-01-0145-FEDER- 006958, and by National Funds of FCT–Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2013.info:eu-repo/semantics/publishedVersio

The effect of nitrogen applications on the growth of young olive trees and nitrogen efficiency

Two field trials (FieldExp1 and FieldExp2) and a pot experiment (PotExp) were c0onducted over a period of 3 years to assess olive tree response to nitrogen (N) applications and to estimate apparent N recovery. FieldExp1 was installed in a 3-year-old olive grove. FieldExp2 consisted of a plantation of young rooted plants. Two treatments were applied in both experiments: N application and a nonfertilized control. In PotExp, 4 N rates were used. In FieldExp1, olive yield significantly increased with applied N in only 1 of the 3 growing seasons. In FieldExp2, aboveground dry matter yield significantly increased with N application. In PotExp, total dry matter yield displayed a typical saturation curve in response to N rates. The poor response of olive yield to N application might be due to the reduced amount of N removed in the crop, and also to the negative interaction found between N application and water deficit. Apparent N recovery reached values varying from 13.1% in FieldExp2 to ~100% in PotExp. The results indicate that the olive response to N and N use efficiency seem to be influenced more by the agroecological conditions defining target yield and N loss, rather than by plant species.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Program PT2020 for financial support to CIMO (UID/AGR/00690/2013). The work was also funded by the INTERACT project “Integrative Research in Environment, Agro-Chains and Technology”, no. NORTE-01-0145- FEDER-000017, in its line of research entitled ISAC, cofinanced by the European Regional Development Fund (ERDF) through NORTE 2020 (North Regional Operational Program 2014/2020).info:eu-repo/semantics/publishedVersio

Genomic Template Stability assessed in almond trees of cv. ‘Vairo’ treated with biostimulants and boron-based fertilizers

Almond is highly produced in the NE of Portugal, where late frosts during flowering, low precipitation, and high temperature in summer affect productivity and quality. In addition to late-flowering cultivars, plant biostimulants (PBs) and boron-based fertilizers have been used to improve cell division, vegetative growth, photoassimilates rate, and nutritional status of almond trees. Despite the wide use of PBs in multiple food crops, the scientific evaluation of their effects is scarce. Our team previously analyzed the effects of PBs and boron-based fertilizers in the mitotic cell cycle of almonds and verified the intensification of cell division without significant anomalies. This work focused on the molecular characterization of three-years-old almond trees of cv. ‘Vairo’ was treated with two PBs (based on seaweed extract and free amino acids) and two boron-based fertilizers (applied on soil and leaves) in a rainfed orchard (NE Portugal) using leaf samples collected through the summer of 2019 in treated trees. Three monthly applications of individual PBs based on seaweed extract (AN), amino acids (AA), and boron ethanolamine (BE) and a unique application of boron on the soil (BS) were made. The molecular stability was assayed by comparing with untreated trees using ISSR, RAPD, IRAP, REMAP, and iPBS markers. The molecular data achieved in ‘Vairo,’ under the edaphoclimatic conditions where it was studied, revealed that AA, BE, or BS treatments induced higher molecular stability, corroborating our previous cytogenetic results.This work was supported by National Funds by the FCT – Portuguese Foundation for Science and Technology under the project UIDB/04033/2020. Author AC thanks to the FCT and UTAD for her contract as a researcher under the scope of D.L. no. 57/2016 of 29 August and Law no. 57/2017 of 19 July.info:eu-repo/semantics/publishedVersio

Liming and application of nitrogen, phosphorus, potassium, and boron on a young plantation of chestnut

European chestnut is the most important cash crop in the highlands of NE Portugal. However, limited data on cropping technique are available to help farmers make decisions. This work is motivated by the lack of data related to chestnut response to fertilizer application. It reports results from a field fertilization trial consisting of the application of a combination of lime (L), nitrogen (N), phosphorus (P), potassium (K), and boron (B), namely LNPKB, NPKB, –NPKB, N–PKB, NP–KB, and NPK–B. Seedlings of chestnut were planted in June 2013 and grown for four growing seasons. Plant height, trunk diameter, and pruning wood were assessed every year and used as indicators of tree crop growth. Elemental leaf analysis and other tools [SPAD-502 chlorophyll meter; Field Scout CM 1000 NDVI (normalized difference vegetation index) meter, and the OS-30p+ fluorometer] were used to assess plant nutritional stresses. In January 2017 soil samples were collected at three depths (0–5, 5–10, and 10–20 cm) to determine several soil fertility parameters. The nonapplication of K and B reduced the tree crop growth and pruning residues. Leaf analysis revealed leaf K and B concentrations respectively in the NP–KB and NPK–B treatments to be in the deficient range previously established for chestnut. SPAD readings and NDVI detected the reduced availability of N associated with the –NPKB treatment but not the reduced plant growth associated with NP–KB or NPK–B treatments. The dark adaptation protocols of FV/FM, FV/F0, and OJIP measurements performed with the OS-30p+ fluorometer failed to diagnose the nutrient stresses detected by leaf analysis or the reduction in plant growth.info:eu-repo/semantics/publishedVersio

Cytogenetic and molecular characterization of almond trees treated with plant biostimulants or boron-based fertilizers

Almond is highly produced in the NE of Portugal, where late frosts during flowering, low precipitation, and high tempera- ture in summer affect productivity and quality. Despite the use of late-flowering cultivars, plant biostimulants (PBs) and boron-based fertilizers can also be used to improve cell division, vegetative growth, photoassimilates rate, and nutritional status. PBs are widely used in some food crops, but the evaluation of their effects is still scarce. We treated three-year- old almond trees of cv. ‘Vairo,’ growing in a rainfed orchard in the NE of Portugal, with four individual treatments: two PBs (based on seaweed extract and free amino acids) and two boron-based fertilizers (applied on soil and leaves). Three monthly applications of seaweed extract (AN), free amino acids (AA), and boron ethanolamine (BE) were made. A single application of boron on the soil (BS) was made. Leaf samples were collected in treated and untreated (control) trees in cytogenetic and molecular analyses through the summer of 2019. The mitotic cell cycle analysis was performed to prepare mesophyll dividing cells stained with silver nitrate, and the molecular stability was assessed with five marker systems. This work aimed to extrapolate which individual treatment conferred higher mitotic cell cycle regularity and molecular stability. The cytogenetic and molecular data achieved in the cv. ‘Vairo,’ under the edaphoclimatic conditions studied, revealed that the individual treatments AA, BE, or BS induced higher leaf mitotic indexes, regular mitosis, and molecular stability, which might increase the photosynthetic area and production.This research was funded by national funds provided by the FCT/MCTES (“Fundação para a Ciência e a Tecnologia/ Ministério da Ciência, Tecnologia e Ensino Superior”) to the research units CIMO (UIDB/00690/2020) and CITAB (UIDB/04033/2020). The research was integrated in the activities of the Operational Group “EGIS: Estratégias para uma gestão integrada do solo e da água em espécies produtoras de frutos secos”, funded by PT2020 and EAFRD (European Agricultural Fund for Rural Development)info:eu-repo/semantics/publishedVersio