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The clonal rootstocks allows preservation of mother tree genetic characteristics, such as vigor and produce a fasciculated root system, with an abundant thin roots. The objective of this research was to determine the effect of fifteen clonal genotypes as rootstocks on the agronomic performance of ‘BRS Kampai’ peach, as well as the technical feasibility of own-rooted trees (without rootstock) in a no-irrigated field condictions, in Pelotas-RS, Brazil. Bagged nursery trees were planted at the field in August, 2014, under a randomized block design with four replications of one tree per plot, and evaluations of trunk diameter, trunk cross-sectional area (TCSA), yield efficiency, annual and accumulated fruit yield per tree and per hectare were carried out until 2019. In the adopted experimental conditions, we conclude that ‘Barrier’ (P. persica x P. davidiana), ‘Cadaman’ (P. persica x P. davidiana), G x N.9 (P. persica x P. dulcis), ‘Ishtara’ [(P. cerasifera x P. salicina) x (P. cerasifera x P. persica)] and ‘Santa Rosa’ (P. salicina) do not have potential as a rootstock of ‘BRS Kampai’ peach due irregular bud breaking of scion, small fruits and/or low fruit yield. Clone 15 (P. mume) stands out for increasing fruit weight and maintaining satisfactory fruit yield per tree. ‘Flordaguard’ (P. persica) is the best rootstock tested, which is vigorous, do not present any undesirable agronomic characteristics and induce the highest yields per tree and per hectare, exceeding 50 t ha-1 in accumulated yield. Own-rooted trees of ‘BRS-Kampai’ peach have technical feasibility, as long as pruning is properly carried out. Resumo Os porta-enxertos clonais permitem a preservação das características genéticas da plantamatriz, tais como o vigor, e produzem um sistema radicular fasciculado, com abundante quantidade de radicelas. O objetivo do presente trabalho foi determinar o efeito de quinze porta-enxertos clonais na performance agronômica de pessegueiros ‘BRS Kampai’, bem como a viabilidade técnica do uso de plantas autoenraizadas (sem porta-enxerto) em condição de campo sem irrigação, em Pelotas-RS, Brasil. Mudas produzidas em sacos plásticos foram plantadas no campo, em agosto de 2014, sob delineamento de blocos casualizados, com quatro repetições, de uma planta por parcela, e avaliações de diâmetro do tronco, área da secção transversal do tronco, eficiência produtiva, produção de frutos por planta e por hectare anual e acumulada foram realizadas até 2019. Nas condições experimentais adotadas, conclui-se que ‘Barrier’ (P. persica x P. davidiana), ‘Cadaman’ (P. persica x P. davidiana), G x N.9 (P. persica x P. dulcis), ‘Ishtara’ [(P. cerasifera x P. salicina) x (P. cerasifera x P. persica)] e ‘Santa Rosa’ (P. salicina) não apresentam potencial como portaenxerto do pessegueiro ‘BRS Kampai’ devido à irregular quebra de dormência das gemas da copa, frutos pequenos e/ou baixa produção. O Clone 15 (P. mume) destaca-se por aumentar o peso do fruto, mantendo satisfatória produção por planta. O ‘Flordaguard’ (P. persica) é o melhor portaenxerto testado, que é vigoroso, não apresenta nenhuma característica agronômica indesejável e induz as maiores produções por planta e por hectare, superando 50 t ha-1 na produção acumulada. Pessegueiros autoenraizados de ‘BRS-Kampai’ apresentam viabilidade técnica de cultivo, desde que as podas sejam adequadamente realizadas.

Strawberry guava (Psidium cattleyanumm Sabine) is a species native to southern Brazil which exhibits significant potential for economic exploitation. The objective of this study was to evaluate the growth response of strawberry guava subjected to liming and phosphate fertilizer in pre-planting. The treatments consisted of four lime levels: 0; 33.3; 66.6 and 100 % of the dose needed to increase the pH in water to 6.0, and four phosphorus (P) doses: 0; 83.3; 166.6 and 250 kg ha–1 of P2O5. Plant growth parameters were evaluated for three years. In the years 2018 and 2019, the mineral composition of leaves, photosynthethic pigment indices and mycorrhizal colonization on strawberry guava roots were measured. Liming and phosphate fertilizer altered neither plant growth nor the photosynthetic pigment indices and there was no interaction between the factors studied and the remaining variables evaluated. However, liming promoted increases in the Ca and Mg shoot content, and the phosphate fertilizer increased the levels of shoot P in the third year of growth. Mycorrhizal colonization was stronger when the P soil levels were low, which could explain the absence of response to phosphate fertilization on plant growth for the first three years after planting.

Among the factors that affect peach productivity is the proper nutrition of plants, being nitrogen (N) one of the main nutrients for the crop. Thus, the objective of the current study was to evaluate the effect of nitrogen fertilization on macronutrient leaf contents, plant development and production of different genotypes of peach trees cultivated at high planting density, seeking to recommend the most appropriate concentration. The experiment was conducted between 2016 and 2018 using peach selections ‘Cascata 1513’ and ‘Cascata 1067’ and with nitrogen fertilization concentrations (0, 60, 120 and 180 kg ha-1 of N). Pruning mass, trunk diameter, number of fruits per plant, average fruit mass, yield per plant, yield per hectare and leaf macronutrients were evaluated. The increase of N concentration increases the N content in leaves. For the conditions of this experiment the maximum production per plant was obtained for the highest dose of 180 Kg ha of N.

The application of rest breaking agents to overcome the lack of chilling is a common practice in apple orchards in southern Brazil. However, its necessity in areas of greater chilling accumulation, like in the city São Joaquim, Santa Catarina State (SC), has been questioned over the years. The aim of this study was to evaluate the effect of different budbreak promoters, on the performance of ‘Fuji Suprema’ apple trees, in the region of São Joaquim/SC. The study was performed at the Experimental Station of São Joaquim - Santa Catarina Agricultural Research and Extension Agency (EPAGRI), in the growing seasons of 2013/2014, 2014/2015, and 2015/2016. Plant material consisted of 10-year-old ‘Fuji Suprema apple trees grafted on the rootstock ‘M.9’ and arranged in a randomized complete block design with five replicates. Treatments consisted of a nutrient solution containing soluble nitrogen and calcium (NCaS), combined with either calcium nitrate or mineral oil, at different rates; and hydrogen cyanamide combined with mineral oil. The time of application was when buds were between the stages A (dormant bud) and B (swollen bud; silver tip). The influence of treatments on flowering, budbreak, yield components, and fruit quality was assessed. Flowering and fruit quality were little affected by treatments. In the other hand, the budbreak promoters consistently improved axillary budbreak in two out of three seasons. Resumo A aplicação de indutores de brotação para superar o baixo acúmulo de frio é uma prática comum em pomares de macieira na região Sul do Brasil. No entanto, sua necessidade em áreas com maior acúmulo de frio, como na cidade de São Joaquim, do Estado de Santa Catarina (SC), tem sido questionada ao longo dos anos. O objetivo deste trabalho foi avaliar o efeito de diferentes indutores de brotação no desempenho de macieiras ‘Fuji Suprema’ na região de São Joaquim-SC. O estudo foi desenvolvido na Estação Experimental de São Joaquim – Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina, nas safras de 2013/2014, 2014/2015 e 2015/2016. Foram utilizadas plantas da cultivar ‘Fuji Suprema’, com 10 anos de idade, enxertadas no porta-enxerto ‘M.9’. O delineamento experimental foi de casualização por blocos, com cinco repetições. Os tratamentos consistiram em solução nutritiva contendo nitrogênio solúvel e cálcio (SNCa), combinado com nitrato de cálcio ou óleo mineral, em diferentes concentrações e cianamida hidrogenada combinada com óleo mineral. A aplicação foi realizada quando as gemas estavam entre os estádios A (gema dormente) e B (gema inchada; ponta prateada). Foi avaliada a influência dos tratamentos na floração, brotação, produção e qualidade do fruto. A floração e a qualidade do fruto foram pouco influenciadas pelos tratamentos. Por outro lado, a brotação de gemas laterais foi consistentemente aumentada pelos produtos testados em duas das três safras em que o estudo foi realizado.

EnglishCover crops may have direct or indirect effects on the physical and chemicalsoil attributes; these cropsplay a key role in the cycling of nutrients in the soil and add labile organic carbon, bringing economic and environmental benefits to the system. To study the effect of cover crops on the physical and chemical properties of an Oxisol, a three-year experiment was conducted in a commercial vineyard located at Epagri’s Experimental Station in Videira, SC, Brazil. Different winter species (white clover, red clover, common vetch, turnip, corn spurrey, black oat, rye, and ryegrass) were sown in addition to treatments with manual weeding or mechanical mowing. Certain chemical and physical attributes of soil were determined in samples collected fromlayers 0-0.1 and 0.1-0.2m deep on the vinerows and between rows, as well as the dry mass of winter cover crops. Few chemical and physical attributes of the soil changed among winter cover crops and did not differ from the crops managed with mechanical mowing or hand weeding of spontaneous vegetation. Vine rows provided more adequate values of most physical and chemical soil attributes. Key words: organic matter; nutrients; bulk density; soil porosity; Vitis spp portuguesAs plantas de cobertura podem apresentar efeitos diretos ou indiretos sobre os atributos fisicos e quimicos do solo, desempenhando papel fundamental na ciclagem dos nutrientes e na adicao de carbono orgânico labil ao solo, trazendo beneficios economicos e ecologicos ao sistema. Para estudar o efeito de plantas de cobertura sobre os atributos fisicos e quimicos de um Nitossolo Vermelho, foi conduzido por tres anos um experimento com semeadura de diferentes especies de inverno (trevo-branco, trevo-vermelho, ervilhaca-comum, nabo-forrageiro, espergula, aveia-preta, centeio e azevem), alem dos tratamentos com capina manual e rocada mecânica, em um vinhedo comercial localizado na Estacao Experimental da Epagri em Videira, SC. Foram determinados alguns atributos quimicos e fisicos do solo em amostras coletadas nas camadas de 0-0,1 e 0,1-0,2m de profundidade na linha e na entrelinha da cultura, alem da massa seca das plantas de cobertura de inverno. As plantas de cobertura do solo alteram poucos atributos quimicos e fisicos do solo e nao se diferenciam do manejo da vegetacao espontânea com capinas manuais ou com rocadas mecânicas. A linha da cultura apresenta valores mais adequados da maioria dos atributos fisicos e quimicos do solo. Palavras-chave: materia orgânica; nutrientes; densidade do solo; porosidade do solo; Vitissp

O trabalho foi realizado no município de São Joaquim, Santa Catarina, durante o ciclo de cultivo 2009/2010, com o objetivo de avaliar a utilização fosfato natural Gafsa combinado com cama de aviário sobre a produtividade de tubérculos e a composição mineral das folhas em um sistema orgânico de produção de batata consumo. O delineamento experimental foi o de blocos ao acaso com cinco repetições e foram testadas quatro doses de fosfato natural Gafsa (0, 1333, 2666 e 4000 kg ha-1) combinadas à dose única de 8 t ha-1 de cama de aviário. Independentemente da dose utilizada, não houve incremento na produção de tubérculos de batata com a adição de fosfato natural Gafsa. A produtividade obtida mesmo com a dose máxima do fosfato natural foi igual em relação a quando se adubou somente com cama de aviário, indicando que a solubilização do fosfato natural Gafsa foi baixa durante um único ciclo de produção da batata. A dose de 8 t ha-1 de cama de aviário propiciou concentrações adequadas dos nutrientes nas folhas, exceto para P e Ca. Devido à baixa concentração de P encontrada nas folhas, presume-se que este nutriente foi o que mais limitou o rendimento de tubérculos.

The aim of this work was to evaluate the effects of orchard fertilization with increasing rates of phosphorus (P) on yield and critical levels of P in the soil and in the leaf of ‘Fuji’ apple trees. The experiment was conducted in São Joaquim, state of Santa Catarina, southern Brazil, from 2010 to 2015, in an Inceptisol soil. The three apple orchards were planted in 2004 with the Fuji cultivar grafted on Marubakaido/ M9 rootstock and grown under a high-plant-density system (1984 trees ha-1). Annual fertilizer levels of 0, 40, 80, 120 and 160 kg ha-1 of P2O5 (as triple superphosphate) were applied to the soil surface, without incorporation, in a randomized block design with five replicates. In the first and last years (2011 and 2015), soil samples were collected from 0-10, 10-20 and 0-20 cm layers and the available P content was analyzed. Annually, whole leaves were collected and analyzed for P content. The number and weight of fruits per tree and hfruit yield were also evaluated. Application of P increased the content of available P in the soil, but this increase was not accompanied by increased leaf P content nor by increased fruit yield. This suggests that, in soils with medium to high content of organic matter and well fertilized with P before planting, there is no response of apple trees for P reapplication in the 10 subsequent years.

The objective of this work was to investigate the effect of liming and phosphorus fertilization on the growth, mineral composition of the leaves, fruit yield, and mycorrhizal colonization of young feijoa (Acca sellowiana) plants. Treatments consisted of four liming levels - 0, 25, 50, and 100% of the dose required to raise the soil pH to 6.5 - and of five levels of P - 0, 60, 120, 180, and 240 kg ha-1 P2O5 -, placed in a randomized complete block design, in a split-plot arrangement, with three replicates. The orchard was established in 2010 with the Helena cultivar. In 2012, 2013, and 2014, plant growth was evaluated by measuring trunk perimeter, plant height, and tree canopy width. Mineral composition of the leaves, regarding P, N, K, Ca, and Mg contents, was assessed annually. Mycorrhizal colonization was evaluated in 2012, and fruit yield was determined in 2014. No interaction was observed between the studied factors. P contents had no effect on the evaluated variables. Liming, however, increases plant growth, mycorrhizal colonization, fruit yield, and Ca and Mg leaf contents, besides reducing K leaf contents. Resumo: O objetivo deste trabalho foi avaliar o efeito da calagem e da adubação fosfatada no crescimento, na composição mineral das folhas, na produção de frutos e na colonização micorrízica de plantas jovens de goiabeira serrana (Acca sellowiana). Os tratamentos consistiram de quatro níveis de calagem - 0, 25, 50 e 100% da dose necessária para elevar o pH do solo a 6,5 - e de cinco níveis de fósforo - 0, 60, 120, 180 e 240 kg ha-1 de P2O5 -, dispostos em delineamento de blocos ao acaso, em arranjo de parcelas subdivididas, com três repetições. O pomar foi implantado em 2010 com a cultivar Helena. Em 2012, 2013 e 2014, o crescimento das plantas foi avaliado por meio da medição do perímetro do tronco, da altura das plantas e do diâmetro das copas. A composição mineral das folhas, quanto aos teores de P, N, K, Ca e Mg, foi avaliada anualmente. A colonização micorrízica foi avaliada em 2012, e a produção de frutos foi determinada em 2014. Não houve interação entre os fatores estudados. Os níveis de P não tiveram efeito sobre as variáveis avaliadas. A calagem, no entanto, aumenta o crescimento das plantas, a colonização micorrízica, a produção de frutos e os teores foliares de Ca e Mg, além de ter reduzido o teor foliar de K.

The application of rest breaking agents to compensate the lack of chilling is a common practice in apple orchards in Southern Brazil. However, its necessity in areas of greater chilling accumulation has been questioned over the years. The aim of this study was to investigate the performance of ‘Maxi Gala’ apple in response to different budbreak promoters in São Joaquim, SC. The study was performed in the growing seasons of 2013/2014, 2014/2015, and 2015/2016. Plant material consisted of 10-year-old ‘Maxi Gala’ apple trees grafted on the rootstock ‘M.9’, arranged in a randomized complete block design with five replicates in the 2013/2014 and 2014/2015 growing seasons and six replicates in the 2015/2016 season. Treatments consisted of Erger®, combined with either calcium nitrate or mineral oil, at different rates; and hydrogen cyanamide combined with mineral oil. Treatments were applied when buds were between the stages A (dormant bud) and B (swollen bud; silver tip). The influence of treatments on flowering, budbreak, yield components, and fruit quality was assessed. Flowering was little affected by treatments, while axillary budbreak was consistently improved in the year of insufficient chilling accumulation. Besides, the combination Erger® (2% and 3%) + calcium nitrate (2% and 3%) and Erger® (1%) + mineral oil (3%) induced similar axillary budbreak as hydrogen cyanamide + mineral oil. Fruit quality attributes were not affected by treatments.

Phosphorus is part of several organic compounds in plant metabolism such as nucleotides and phosphoproteins, in addition to participating in metabolism and energy storage. This study aimed to evaluate the response of peach trees cv. Sensação to phosphate fertilization and establish the critical level of this nutrient in soil and leaves. The experiment was conducted in the 2016 and 2017 cycles in a commercial orchard located in Morro Redondo, RS, Brazil. The experimental design was a randomized block design with four replications. Peach trees were fertilized with increasing doses of phosphorus (P) of 0, 20, 40, 60, and 80 kg ha?1 of P2O5 as triple superphosphate. In the two evaluated cycles, samples of soil at a depth of 0–20 cm and leaves were collected to determine mineral contents. The data were submitted to analysis of variance by the F test (P < 0.05), and when the effects were significant, regression equations were adjusted. P application increased the contents of this nutrient in the soil. Leaf P contents were not affected by fertilization, as well as productivity and yield components. Thus, the critical level of P in soil and peach leaves could not be established. In soils where P contents are classified as medium and high, there is no need to apply this nutrient.

Nitrogen (N) and potassium (K) are usually found in higher concentrations than other macronutrients in apple (Malus x domestica Borkh) fruits and are most frequently associated with changes in fruit quality. The aim of this article was to evaluate the effects of N and K fertilization on some fruit quality attributes of Fuji apple. The experiment was conducted at Sao Joaquim, State of Santa Catarina, Brazil, during 2004 and 2005. A factorial design was used with N and K annual fertilizer rates (0, 50, 100, and 200 kg ha−1 of N and K2O) replicated in three orchards. Fifteen days prior to harvest, three fruit samples were collected from each treatment and site. One sample was used for total soluble solid content (TSS), titratable acidity, pulp firmness, and fruit color parameter analyses, and the other samples were refrigerated in a conventional atmosphere for 3 and 6 months for subsequent determination of fruit quality. Nitrogen fertilization negatively affected fruit color, flesh firmness, and TSS...

The aim of this study was to evaluate the response to phosphorus (P) and potassium (K) fertilization and to establish the critical levels of P and K in the soil and in the plant tissue in pear trees. Two experiments were conducted in São Joaquim (SC), Brazil. In experiment 1, the plants received annually the application of increasing rates of phosphate fertilizer (0, 40, 80, 120 and 160 kg P2O5 ha-1), while in experiment 2, increasing rates of potassium fertilizer (0, 40, 80, 120 and 160 kg K2O ha-1) were applied annually. In the two experiments, soil was collected annually from the 0-10, 10-20 and 0-20 cm layers, and the available P (experiment 1) and exchangeable K (experiment 2) content was analyzed. Whole leaves were collected annually, which were subjected to analysis of total P (experiment 1) and total K (experiment 2) content. The number and weight of the fruits per plant and fruit yield were evaluated. Application of P on the soil planted with pear trees increased the nutrient content in the soil and, in most crop seasons, in the whole leaf, but it did not affect the yield components and fruit yield. The application of K on the soil with pear trees increased the nutrient content in the soil and, in most of the crop seasons, in the whole leaf, but the potassium content in the whole leaf decreased in the crop season with greater fruit yield. The yield components and fruit yield were not affected by K fertilization. O trabalho objetivou avaliar a resposta à adubação com fósforo (P) e potássio (K) e estabelecer o nível crítico no solo e no tecido de P e K em pereira. Dois experimentos foram conduzidos em São Joaquim (SC). No experimento 1 as plantas receberam anualmente a aplicação de doses crescentes de fertilizante fosfatado (0; 40; 80; 120 e 160 kg de PO5 h2a-1), enquanto no experimento 2 foram aplicadas anualmente doses crescentes de fertilizante potássico (0; 40; 80; 120 e 160 kg de K2O ha-1). Nos dois experimentos foi coletado anualmente solo nas camadas de 0-10; 10-20 e 0-20 cm, onde foi analisado o teor de P disponível (experimento 1) e K trocável (experimento 2). Anualmente foram coletadas folhas completas que foram submetidas à análise do teor total de P (experimento 1) e K (experimento 2). Avaliaram-se o número e a massa dos frutos por planta e a produção de frutos. A aplicação de P no solo cultivado com pereira incrementou o teor do nutriente no solo e, na maioria das safras, na folha completa. Porém, o incremento do teor de P disponível no solo e na folha não foi acompanhado de aumentos nos componentes de produção e na produção de frutos, impossibilitando o estabelecimento do nível crítico de P no solo e no tecido. A aplicação de K no solo aumentou o teor do nutriente no solo e, na maioria das safras, na folha completa da pereira, mas o teor de K na folha completa diminuiu na safra com maior produção de frutos. O incremento de K trocável no solo e na folha não foi acompanhado de aumentos nos componentes de produção e na produção de frutos, não permitindo o estabelecimento do nível crítico de K no solo e no tecido.

A area plantada com amora-preta (Rubus spp.) aumentou 100% nos ultimos anos no Brasil. Mas pelo fato de ser uma cultura de importância economica recente, ha pouca informacao sobre sua nutricao e efi ciencia da adubacao. O objetivo deste trabalho foi apresentar e discutir aspectos nutricionais desta cultura que vem crescendo em importância, especialmente entre pequenos produtores. Foram abordados, temas como teor de materia orgânica e pH do solo ideais para a cultura; alem do manejo da fertilidade atraves de adubacao mineral, com destaque para doses e fontes de nitrogenio, fosforo e potassio recomendadas, assim como, os principais sintomas de defi ciencia de macro e micronutrientes tipicos da cultura. Observou-se que ha, atualmente, uma grande discrepância na literatura sobre o teor de materia orgânica do solo e pH ideais e doses de fertilizantes minerais recomendadas.Verifi cou-se, tambem, a necessidade de mais estudos em diversos aspectos da nutricao desta cultura. Sendo importante a elaboracao de recomendacoes de adubacao baseadas em resultados de experimentos realizados a campo em diferentes locais e com diferentes cultivares ou grupos de cultivares. Podendo ser adotado o criterio do habito de crescimento ou a presenca de espinhos como carater de agrupamento das cultivares.

This study evaluated the diversity of cultivable plant growth-promoting (PGP) bacteria associated with apple trees cultivated under different crop management systems and their antagonistic ability against Colletotrichum gloeosporioides. Samples of roots and rhizospheric soil from apple trees cultivated in organic and conventional orchards in southern Brazil were collected, together with soil samples from an area never used for agriculture (native field). Bacteria were identified at the genus level by PCR-RFLP and partial sequencing of the 16S rRNA, and were evaluated for some PGP abilities. The most abundant bacterial genera identified were Enterobacter (27.7%), Pseudomonas (18.7%), Burkholderia (13.7%), and Rahnella (12.3%). Sixty-nine isolates presented some antagonist activity against C. gloeosporioides. In a greenhouse experiment, five days after exposure to C. gloeosporioides, an average of 30% of the leaf area of plants inoculated with isolate 89 (identified as Burkholderia sp.) were infected, whereas 60 to 73% of the leaf area of untreated plants was affected by fungal attack. Our results allowed us to infer how anthropogenic activity is affecting the bacterial communities in soil associated with apple tree crop systems, and to obtain an isolate that was able to delay the emergence of an important disease for this culture.

Nitrogen (N) and potassium (K) are closely related to orchard productivity, since they are usually found in higher concentrations than others macronutrients in apple (Malus × domestica Borkh) fruits. This research was carried out to assess the effect of eight years of soil additions of N and K on yield, fruit size and mineral composition of 'Fuji'/Marubakaido apple in São Joaquim, State of Santa Catarina, Southern Brazil. A factorial design was used with N and K annual fertilizer rates (0, 50, 100, 200 kg ha-1 of N and K2O) replicated in three orchards from 1998 to 2006. Yield was estimated by multiplying the total number of fruit per tree by the mean weight of 100 randomly sampled fruit. Fifteen days prior to harvest, 24 fruit pulps were analyzed for N, K, Ca and Mg contents. Increases in yields were noticed in five and four years, due to the N and K fertilizer additions, respectively. Fruit size was more affected by K than by N fertilization. Fruit mineral composition was affected by both N and K fertilization. N concentration and N:Ca ratios were enlarged by N fertilization. K concentration and K:Ca ratios were also enlarged by K fertilization. Ca fruit concentration was reduced by N fertilization and often by K. Ca-related fruit disorders were not observed even after 180 days storage. However, N and K fertilization affected Ca nutrition. Thus, when fertilizing with N and K, it is imperative to use combined practices in order to offset the detrimental effect that these nutrients may cause on Ca concentration in the fruit. O nitrogênio (N) e o potássio (K) são os nutrientes mais exportados pelas maçãs (Malus domestica Borkh) e por isso estão diretamente relacionados com a produtividade dos pomares. O objetivo desse trabalho foi avaliar a influência das adubações anuais com nitrogênio e potássio sobre o rendimento, tamanho e composição mineral de maçãs 'Fuji' enxertada sobre o Marubakaido. O experimento foi conduzido nos anos de 1998 a 2006, no município de São Joaquim-SC, Brasil. Consistiu de um fatorial com doses de N e K aplicadas anualmente ao solo (0, 50, 100 e 200 kg ha-1 de N e de K2O) e repetidas em três pomares comerciais. O rendimento foi estimado a partir da contagem do número total de frutos por planta e multiplicado pelo peso médio de 100 frutos amostrados aleatoriamente por parcela. Quinze dias antes da colheita, 24 frutos foram amostrados para fins de determinação das concentrações de N, K, Ca e Mg. As adubações nitrogenada e potássica aumentaram o rendimento da macieira em cinco e quatro dos oito anos avaliados, respectivamente. O tamanho dos frutos foi mais afetado pela adubação potássica que pela nitrogenada. As adições de N e K influenciaram a composição mineral dos frutos, incrementando suas concentrações e as relações N:Ca e K:Ca. A concentração de Ca nos frutos foi reduzida pela adubação nitrogenada e frequentemente pela potássica. Distúrbios fisiológicos relacionados com a deficiência de Ca não foram observados, mesmo após 180 dias de armazenagem. Entretanto, a nutrição do Ca foi influenciada pelas adubações nitrogenada e potássica. Por isso, ao aplicar-se N e K deve-se combinar práticas nutricionais que compensem a redução da concentração de Ca nos frutos que esses nutrientes promovem.

O trabalho foi realizado no município de São Joaquim, estado de Santa Catarina, em dois ciclos de cultivo (1999/00 e 2001/02), tendo como objetivo verificar o efeito da adubação nitrogenada, fosfatada e potássica na produtividade de tubérculos de batata-semente. O delineamento experimental foi de blocos ao acaso com quatro repetições. Foram testadas três doses de N e K(2)0 (0; 150 e 300 kg ha-1) e quatro doses de P2O5 (0; 350; 700 e 1050 kg ha-1). A produção de tubérculos foi afetada pela adubação nitrogenada e fosfatada e, dependendo do ciclo de cultivo, também pela potássica. O fósforo foi o nutriente que promoveu o maior incremento da produção de tubérculos. A batata respondeu a doses de 694 a 920 kg ha-1 de P2O5, dependendo do ano de cultivo e da dose de nitrogênio envolvida. Essas quantidades foram superiores àquelas recomendadas oficialmente para os estados do Rio Grande do Sul e de Santa Catarina. This work was carried out in São Joaquim, Santa Catarina State, Brazil, in two cultivation cycles (1999/00 and 2001/02), to evaluate the effect of the nitrogen, phosphorus and potassium fertilization on the tuber yield of potato-seed. The experiment had a randomized block design with four replicates. Three levels of N and K2O (0; 150 and 300 kg ha-1) and four rates of P2O5 (0; 350; 700 and 1050 kg ha-1) were tested. The tuber production was affected by the nitrogen and phosphorus fertilization and, depending on the cultivation cycle, also by the potassium one. The yield was increased by P2O5 rates from 694 to 920 kg ha-1 depending on the cultivation cycle and nitrogen rates. These amounts were higher than those recommended by the official institution for Santa Catarina and Rio Grande do Sul States.