Gilberto Nava

Produção de tubérculos de batata-semente em função das adubações nitrogenada, fosfatada e potássica

This work was carried out in Sao 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.

Cultivable bacteria isolated from apple trees cultivated under different crop systems: Diversity and antagonistic activity against Colletotrichum gloeosporioides

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.

Soil composition and nutritional status of apple as affected by long-term application of gypsum

Gypsum does not affect the soil negative charges and maintains sulfate in the soil solution, making it one of the cheapest products to increase Ca activity in soil solution, especially in the deeper soil layers. Higher Ca levels in the soil solution can increase the uptake of this nutrient by apple trees, reducing the risk of physiological disorders caused by Ca deficiency. This study assessed the effect of long-term gypsum application on some soil properties and on the chemical composition of leaves and fruits of an apple cultivar susceptible to fruit disorders associated with low Ca. The experiment was conducted in Sao Joaquim, in the South of Brazil, from 2001 to 2009. Gypsum rates of 0, 1.0, 2.0 and 3.0 t ha-1 were annually broadcast over the soil surface, without incorporation, in an apple orchard with cultivar ´Catarina´, planted in 1997. Gypsum application over eight consecutive years had no effect on soil exchangeable K and Al to a depth of 80 cm, but increased exchangeable Ca in the sampled layers (0-10, 10-20, 40-60 and 60-80 cm), while exchangeable Mg decreased only in the surface layer (0-20 cm). Gypsum did not affect the concentration of any nutrient in the fruits, including Ca. The same was verified in the leaves, except for Mg which decreased with increased gypsum rate. Despite increasing the availability of Ca in the soil profile to a depth of 80 cm, gypsum was not effective to increase the Ca content in leaves and fruits of an apple cultivar susceptible to Ca deficiency grown in an appropriately limed soil.

Adubação de crescimento de macieira Cv. Catarina sobre porta-enxerto marubakaido em São Joaquim-SC

ABSTRACT - The vegetative vigor and the yield potential of the apple trees primarily depend on the initial soil fertilization (growingor plant formation fertilization), which is based mainly on nitrogen application. The “Catarina” apple cultivar selected as sca b resistant,seems to be a promising cultivar for higher altitude areas in Southern Brazil. As a new cultivar, fertilizer recommendations fo r the initialplant formation have not been available yet. For this reason, an experiment was carried out to establish the nitrogen requirement tobalance both vegetative vigor and the plant yield potential. The orchard was planted in August 1998 in a shallow soil originated fromacid magmatic rocks, in Sao Joaquim – SC, Brazil. The cultivar studied was Catarina grafted onto Marubakaido rootstock. The ar ea hadbeen limed to elevate the soil pH; phosphorous and potassium were supplied according to fertilizer recommendations. The N ratestested were: 0, 25, 50 and 100 kg ha -1 (sum of three annual applications beginning from the subsequent year to the plantation), placedon the projection of the tree canopy. Eight plants organized in randomized blocks design with eight replications formed the plots. Thebranches growth of the year and the number of spurs were not affected by any N rates. However, it was supposed that the nitrogenfertilization from previous years had affected the fruit buds nutrition, considering the significant increasing of the number o f fruits andthe yield of the trees on first year of production.Index terms : nitrogen, apple trees, young tree fertilization.

THE PEAR TREE RESPONSE TO PHOSPHORUS AND POTASSIUM FERTILIZATION

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 Sao 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.

Organic fertilization and weed control effects on yield and growth of 'Fuji' apple

Organic fertilization and soil management can interfere directly on yield and growth of apple trees, especially in shallow soils. This study evaluates the influence of poultry litter rates and methods of weed control on yield and growth of apple trees. The experiment was carried out on an Inceptisol, cultivated with apple for 13 years, cv. Fuji on rootstock Marubakaido, located in Sao Joaquim, SC. Since 1998, two methods of weed control were used, one with herbicide and other with mowing both associated with four poultry litter rates (0, 5, 10 and 20 t ha-1) applied annually to soil. The experimental design was complete randomized blocks, with split-plot arrangement and four replications. The yield of apple trees was increased by addition of poultry litter and it was dependent on the method of weed control. Regarding the mowing method, it was necessary to apply a higher rate of organic fertilizer to achieve the same yield observed for the herbicide method. The application of litter poultry promoted the recovery of plant growth and in a more efficient way when herbicide was used as weed control.

‘FUJI’ APPLE TREE RESPONSE TO PHOSPHORUS FERTILIZATION

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.

Mineral composition of leaves and fruits of apple ‘Fuji’ on different rootstocks in the region of São Joaquim-SC

This work evaluated the mineral composition of leaves and fruits of apple (Malus domestica Borkh) ‘Fuji’ on different rootstocks. The experiment was conducted from 2008 to 2011 in the municipality of São Joaquim (SC). The treatments evaluated rootstocks: CG.008, CG.24, CG.56, CG.058, CG.210, CG.213, CG.757, CG.814 and CG.969 of the American series Cornell Geneva (CG); JM.2 and JM.7 of the Japanese series Japan, Morioka (JM); and M.7, M.9 and M.26 of the English series, EMLA (M). The experimental design was randomized blocks with four repetitions. Annually, the leaves were collected for the chemical analysis. Only in the years 2009 and 2010, the fruit samples were collected to determine nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg). The leaf Ca content differed between rootstocks, especially for CG.213 and CG.969, which presented a higher content of the nutrient. However, there were no differences between rootstocks in terms of Ca content in the fruit, which confirms the low ratio between the contents in leaves and fruits. Ratios between nutrients, mainly (K+Mg)/ Ca, are more sensitive to the Ca content to discriminate groups of rootstocks about possible risk of physiological disorders in the fruits. Indexation terms: Malus domestica, mineral nutrition, physiological disorders, fruit quality. Composição mineral de folhas e frutos da macieira ‘Fuji’ em diferentes porta-enxertos na região de São Joaquim-SC Resumo – O trabalho objetivou avaliar a composição mineral de folhas e frutos de macieira (Malus domestica Borkh) ‘Fuji’ sobre diferentes porta-enxertos. O experimento foi conduzido durante o período de 2008 a 2011, no município de São Joaquim (SC). Os tratamentos consistiram na avaliação de 14 porta-enxertos: CG.008, CG.24, CG.56, CG.058, CG.210, CG.213, CG.757, CG.814 e CG.969 da série americana Cornell Geneva (CG); JM.2 e JM.7 da série japonesa Japan, Morioka (JM); e M.7, M.9 e M.26 da série inglesa, EMLA (M). O delineamento experimental foi em blocos ao acaso, com quatro repetições. Anualmente, foram coletadas as folhas para a análise química. Apenas nos anos de 2009 e 2010, as amostras de frutos foram coletadas para determinação de nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca) e magnésio (Mg). O teor foliar de Ca diferiu entre porta-enxertos, com destaque para CG.213 e CG.969, os quais apresentaram maior teor do nutriente. Entretanto, não houve diferenças entre porta-enxertos em relação ao teor de Ca no fruto, o que confirma a baixa relação entre os teores nas folhas e nos frutos. As relações entre os nutrientes, principalmente de (K+Mg)/Ca, são mais sensíveis que o teor individual de Ca para discriminar grupos de porta-enxertos quanto ao possível risco de apresentar distúrbios fisiológicos nos frutos. Termos para indexação: Malus domestica, nutrição mineral, distúrbios fisiológicos, qualidade de frutos. 1Agronomist, Doctor in Soil Science and Plant Nutrition, Embrapa Clima Temperado , Pelotas, RS-Brasil, E-mail: gilberto.nava@embrapa.br 2Agronomist, Doctor in Soil Science, Researcher of the Estação Experimental de São Joaquim/ São Joaquim,SC-Brasil, E-mail: marlise@epagri.sc.gov.br 3Assistant Professor, Department of Horticulture, Oregon State University, Mid-Columbia Agricultural Research and Extension Center, 3005 Experiment Station Drive, Hood River, OR 97031, E-mail: mateus.pasa@gmail.com 4Agronomist, Master in phytopathology, Researcher of the Empresa Fito Desenvolvimento e Produção, São Joaquim-SC-Brasil. E-mail: fito.boneti@gmail.com

Performance of ‘Fuji Suprema’ apple trees treated with budbreak promoters, in São Joaquim-SC

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.

Leaf nutrient content on seven plum cultivars with grafted by budding or own-rooted trees.

1Agricultural Engineer Dr., Embrapa Clima Temperado, BR 392, km 78, Caixa Postal 403, CEP 96010-971, Pelotas, Rio Grande do Sul State, Brazil. E-mail: alex.mayer@embrapa.br; bernardo.ueno@embrapa.br; gilberto.nava@embrapa.br 2Environmental management student and scolarship at Embrapa Clima Temperado, BR 392, km 78, Caixa Postal 403, CEP 96010-971, Pelotas, Rio Grande do Sul State, Brazil. E-mail: taina4919@hotmail.com Abstract Several studies have been conducted in Brazil with rooting of plum scion cultivars, however, it is not known the performance and benefits of own-rooted trees at field. This study aimed to evaluate the leaf nutrient content (N, P, K, Ca, Mg, Fe, Mn, Zn, Cu and B) in seven Japanese plum cultivars (Prunus salicina) on the 2nd and 3rd year after field planting, whose nursery trees were produced by “T-inverted” budding method over ‘Capdeboscq’ peach (P. persica) or by own-rooted hardwood cuttings. The experimental design was in randomized blocks, factorial 7 x 2 (cultivars x nursery tree types), with five replicates of one tree per plot. We conclude that leaf nutrient content of Japanese plums varies among cultivars; however there is no cultivar that stands out in all macro and micronutrients evaluated. K, Ca and Mn leaf contents, when affected by nursery tree types tested, were always higher in own-rooted trees. However, Mg leaf contents, when affected by nursery tree types tested, were always higher in budded trees on ‘Capdeboscq’ peach. Own-rooted plum trees of ‘Amarelinha’, ‘Blood Plum’, ‘Pluma-7’ and ‘Reubennel’ presented higher Mn leaf contents, in relation to budded trees of these cultivars on ‘Capdeboscq’. Own-rooted ‘Cerejinha’ plum trees have highest K leaf content and also increase the agronomic interpretation class in relation to the budded trees of this cultivar on ‘Capdeboscq’.