Fruit Production Systems Research Articles

Integrated and Organic Fruit Production Systems for ‘Liberty’ Apple in the Northeast United States: A Systems-based Evaluation

A systems-based approach was used to evaluate integrated (IFP) and organic fruit production (OFP) (during and after the transition period) in an established high-density commercial orchard of disease-resistant ‘Liberty’ apples (Malus ×domestica Borkh.). Agroecological and economic evaluations included: yields, tree growth, leaf nutrient levels, arthropod and cosmetic fruit damage, environmental impacts, variable costs of production, and potential crop value using both direct market and wholesale market prices. Cumulative yields (2004–2007) of both harvested and total (harvested + dropped) fruit were not different between the two systems. Tree size (trunk cross-sectional area) was not consistently different between the production systems. The IFP-grown apples had between 3% and 6% insect damage (within normal percentages for this region) and between 3% and 17% total damage (either internal or cosmetic). The OFP-grown apples had between 3% and 25% insect damage and 3% to 75% total damage, varying greatly from year to year. In 2006, superficial blemishes, caused by diseases and scarfskin, were extensive on OFP-grown fruit. Using the Environmental Impact Quotient, the potential negative environmental impacts were estimated to be six times greater in the OFP system, largely as a result of the use of lime sulfur and fish oil for thinning and the large quantity of kaolin clay used for pest control. Partial budgets of both systems estimated variable production expenses to be 9% greater for OFP. Sales value was estimated to be 6% greater for OFP than IFP using direct market prices (e.g., farm stand or farmers' market) and 11% greater for IFP than OFP using wholesale market prices. A 56% premium was used to calculate the OFP crop value in the third and fourth years (fruit could have been sold with an organic label after 36 months from the last organically prohibited material). Four years of evaluation suggested that IFP could be widely implemented in the northeastern United States, but the lack of market incentives might impede its adoption. Producing disease-resistant apples under an OFP system also showed potential for success, but a price premium would be needed to offset the reduced profitability incurred from arthropod pests, poor fruit finish, and small fruit size.

Potential for controlling codling moth Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) in Argentina using the sterile insect technique and egg parasitoids

AbstractCodling moth is the main pest affecting apples and pears worldwide. Most pest control strategies used against this insect have relied on the use of broad‐spectrum insecticides which have led to non‐desirable effects like pesticide resistance, residues in the environment, human health concerns and the reduction of access to international markets. Therefore, alternative pest control strategies that would result in sustainable fruit production systems while taking care of the environment are strongly promoted. The use of the sterile insect technique has proven to be a valuable pest control tactic within area‐wide integrated pest management strategies, and its synergistic effect for Lepidoptera pests when combined with other biological control tactics such as parasitoids has been documented. The purposes of this research were to evaluate the response of an Argentinean codling moth strain to a sub‐sterilizing radiation dose of 100 Gy and to assess the acceptability and suitability of sterile codling moth eggs by the egg parasitoids, Trichogramma cacoeciae (Marchal) and Trichogramma nerudai (Pintureau and Gerding). Irradiated female moths survived better than irradiated male moths and non‐irradiated male and female moths. Also, the fecundity of irradiated female moths was reduced by more than 30% as compared to non‐irradiated ones whereas their fertility was close to zero. The F1 generation was male biased with a lower fertility (inherited sterility) than the parental generation. Trichogramma cacoeciae and T. nerudai parasitized both fertile and sterile eggs. However, there was a significant reduction in acceptability for sterile eggs. Trichogramma nerudai parasitized more eggs than T. cacoeciae, but egg acceptability for this species was proportionally lower than for T. cacoeciae especially on eggs oviposited by irradiated females. Development to adult of both parasitoids species was not substantially affected by the origin of the eggs and the wasps had acceptable levels of adult emergence, survival and fecundity. These results provided useful information on the potential for controlling the codling moth using egg parasitoids and the sterile insect technique in Argentina.

Managing Cuscuta gronovii (Swamp Dodder) in Cranberry Requires an Integrated Approach

Dodders (Cuscuta spp.) are parasitic plants that threaten the sustainability of many crops. Because this parasite is very adept and successful from biological and ecological perspectives, a single control strategy is unlikely to provide sufficient economic control. Dodder (C. gronovii) is a particularly serious pest in commercial cranberry (Vaccinium macrocarpon) production. Multiple viable strategies must be integrated and tailored into a weed management plan to provide acceptable control. The key to sustainable management of this serious pest will require a combination of chemical and cultural approaches, supported by understanding the complicated nature of dodder biology. Research from small fruit production systems like cranberry into the biology of dodder (e.g., germination patterns, host preference, use of plant growth regulators) may provide insights that could ultimately be useful for other crop system management plans. This paper will present the current knowledge base for integrated management of dodder in cranberry as well as highlight relevant research from other crops and potential topics for future research.

Soil Organic Carbon and Nitrogen Stocks under Tropical Organic and Conventional Cropping Systems in Northeastern Brazil

Soil organic matter (SOM) is an essential ecosystem component whose dynamics are affected by soil management practices. To evaluate the impact of two agricultural systems (organic and conventional) on soil organic carbon (C) and nitrogen (N) stocks in a sandy soil, samples were collected from the Amway Nutrilite Brazil farm and from the Central Pivot Horticultural Farmers Association farm, both situated in the Chapada da Ibiapaba region, Ceará State, Brazil. The first area has a large‐scale Caribbean Cherry fruit production system under organic management, whereas the second represented a conventional soil cultivation condition, characterized by the use of chisel plow and disc plow, mineral fertilization, and herbicides application. Plots with and without green manure fertilization were compared in the organically cultivated systems by using soil samples collected in the rows and between the rows. Areas under native forest were also sampled to determine the steady‐state condition. Total organic C and N contents in the soil (SOC, TN) and in the humic substances were determined at the 0‐ to 5‐, 5‐ to 15‐, 15‐ to 30‐, and 30‐ to 50‐cm soil layers. In addition, oxidizible organic C fractions were measured to calculate the carbon management index (CMI). In general, total SOC levels were low, ranging from 2.5 to 12.6 g kg−1 in the whole soil profile among the organic systems. In the upper soil layer, SOC and TN stocks were greater in the rows in response to organic fertilization. The conventional system presented lower variation on the SOC contents throughout soil layers when compared to the native forest area, indicating the direct effect of plowing on the downward SOC distribution. The CMI data confirmed the reestablishment of SOM levels in the rows of the organic managed systems in relation to the reference area, whereas the reduction of the CMI in the conventional system suggests a decline in the soil quality and greater potential for increased C losses to the atmosphere.

Emergy and economic evaluations of four fruit production systems on reclaimed wetlands surrounding the Pearl River Estuary, China

Emergy and economic methods were used to evaluate and compare a traditional tropical fruit cultivation system, for bananas, and three newly introduced fruit cultivation systems, for papaya, guava and wampee, on reclaimed wetlands of the Pearl River Estuary, China. The goal of this study was to apply ecological engineering principles to fruit production system designs to maximize total emergy benefits and sustainability. The evaluations considered input structure, production efficiency, environmental impacts, economic viability and sustainability. The market effects on emergy exchange were assessed both for purchasing the inputs to production and for selling the fruit. These market effects were also considered in the evaluation of sustainability by using the Emergy Index for Sustainable Development (EISD), which was evaluated with and without taking the change in natural capital (i.e., soil organic matter) into consideration. The results showed that all three of the newly introduced systems are much more sustainable than the traditional banana production system. The guava production system had the highest value of the Emergy Sustainability Index (ESI = 0.40). The high price of wampee gave it the highest economic yield/cost ratio (4.87) and EISD (0.73). Emergy and economic evaluations are complementary methods, with emergy analysis shedding more light on environmental support and impacts of the production systems not considered in the market value, and economic analysis focusing on the effects of markets on fruit production. The Emergy Exchange Ratio (EER) was proposed as a bridge between emergy and economic evaluations for specific systems and/or processes.

Effect of reduced spray programmes on incidences of apple scab, powdery mildew and codling moth damage in environmentally freindly apple production systems

Still a large amount of pesticides and spary applications are used in environmentally friendly fruit production systems; therefore, the aim of our study was first to test the in vitro effeicacy of some fungicides against a key apple disease (apple scab), and secondly to evaulate the effectiveness of reduced spray programmes against apple scab, powdery mildew and coding moth in integrated and organic apple orchards. In vitro efficacy of 7 fungicides (Champion 50 WP, Kocide 2000, Nordox 75 WG, Olajos rézkén, Kumulus S, Rézkén, Rézoxiklorid) and another 6 fungicides (Score 25 EC, Efuzin 500 SC, Systane, Folicur Solo, Zato Plusz, Rovral) approved in organic and integrated production systems, respectively, were tested against apple scab. Altogether four spray programmes were performed i) standard integrated: sprays followed by forecasting systems during the season, ii) reduced integrated: sprays followed by forecasting systems but only 75% of the spray numbers used during the season-long spray programme, iii) standard oragnic: sprays applied every 7–14 days during the season and iv) reduced organic: 60% of the spray numbers used during the season-long spray programme. In vitro results showed that fungicides (with active ingredients of copper and sulphur) applied in organic production showed relatively high percent growth capacity of the apple scab fungus. Rézkén showed the highest and Kumilus S the lowest efficacy against apple scab. Fungicides applied in integrated production showed relatively low percent growth capacity of the apple scab fungus. Score 25 EC showed the highest and Rovral the lowest efficacy against apple scab. Field study showed that reduced spray programmes did not increase significantly scab incidence in the integrated field. However, scab incidence increased significanly (above 30%) in the reduced spray programme for the organic orchard.Mildew incidence was low (below 5%) in both integrated and organic spray programmes. Mildew incidence on both shoots and fruits increased significanly in the reduced spray programme for the organic orchard. Incidence of codling moth damage was affected the most by standard vs. reduced spray programmes. Though incidence remained below 10% in the integrated plots, the incidence was significantly higher in the reduced spray programme compared to the standard programme. Similar results were obtained for organic spary programmes, but the incidence was 10 times higher and the differences among the two programmes were larger.,

Maturity and Quality of ‘Liberty’ Apple Fruit Under Integrated and Organic Fruit Production Systems Are Similar

Maturity and quality of fruit harvested from an orchard of disease-resistant ‘Liberty’ apple (Malus ×domestica Borkh.) trees was investigated during and after the transition from conventional to integrated (IFP) and organic fruit production (OFP) systems. Over 4 years, internal ethylene concentration, starch pattern index, flesh firmness, soluble solids concentration (SSC), titratable acidity (TA), and percent of surface blush of fruit at harvest were not consistently different between fruit from IFP and OFP systems. Total phenolic content and antioxidant capacity of the fruit were also similar between treatments. IFP-grown fruit contained more potassium during the first 2 years and more calcium in all years than OFP-grown fruit. After fruit were stored in air at 0.5 °C for 9 weeks in 2007, OFP-grown apples were firmer and had higher SSC, TA, and SSC:TA ratios. In double-blind triangle taste tests, consumer panelists were able to discriminate between the fruit from each treatment, but in double-blind hedonic and intensity tests, panelists did not consistently rate one treatment more highly than the other. Overall, consumer panelists favorably rated internal quality of fruit grown under both IFP and OFP systems. In 2006, when weather and disease caused a high percentage of OFP-grown fruit to have cosmetic defects, the panelists rated the appearance of OFP-grown apples as less acceptable than the cleaner-looking IFP-grown apples. Our study of ‘Liberty’ apple fruit maturity and quality during a 4-year transition period from conventional to IFP and OFP systems showed that differences were small if present, whereas internal fruit quality was rarely different between systems.

Organic fruit production in British Columbia

British Columbia has climatic conditions suitable for the production of a wide range of high-value fruit crops, and has the highest rate of increase of organic production in Canada. This review assesses the current status of organic fruit production using a case study of the three most valuable fruit crops currently grown: apple (Malus × domestica Borkh.), grape (Vitis vinifera L.) and high bush blueberry (Vaccinium corybosum L.). The review emphasizes the current status of organically acceptable management of crop resources and crop protection from insects and diseases. Central to organic production are soil management strategies designed to maintain soil fertility and increase soil biological activity and biodiversity by increasing soil organic matter content. Composts and organic amendments that require vigilant testing of their variable and often lower nutrient content are substituted for the chemical fertilizers of conventional production. Increased effort to manage vegetation within and between planting rows is necessitated by an inability to use herbicides. Thus, techniques such as mulching, cultivation and cover cropping are important. Management of insects and diseases requires detailed information of the agro-ecosystem and the unique interactions between pests and specific crops. Organic approaches to minimize pest damage include altered production practices or applications of organically approved control products. Some aspects of organic production systems have received little or no research. In irrigated areas, there is little information available on water management that supports conservation and the specific needs of organic production systems. Historically, research on organic production systems has not received the financial support allocated to conventional system research. Many research needs are identified in this review both applicable to all three fruit crops studied, but also specific to the individual crop. It is argued that future consumer demand calls for an acceleration of research on organic fruit production systems. Key words: Malus × domestica Borkh., organic soil, insect and disease management, Vaccinium corybosum L., Vitis vinifera L.

Climate change effects on winter chill for tree crops with chilling requirements on the Arabian Peninsula

Fruit production systems that rely on winter chill for breaking of dormancy might be vulnerable to climatic change. We investigated decreases in the number of winter chilling hours (0–7.2°C) in four mountain oases of Oman, a marginal area for the production of fruit trees with chilling requirements. Winter chill was calculated from long-term hourly temperature records. These were generated based on the correlation of hourly temperature measurements in the oases with daylength and daily minimum and maximum temperatures recorded at a nearby weather station. Winter chill was estimated for historic temperature records between 1983 and 2008, as well as for three sets of synthetic 100-year weather records, generated to represent historic conditions, and climatic changes likely to occur within the next 30 years (temperatures elevated by 1°C and 2°C). Our analysis detected a decrease in the numbers of chilling hours in high-elevation oases by an average of 1.2–9.5 h/year between 1983 and 2008, a period during which, according to the scenario analysis, winter chill was sufficient for most important species in most years in the highest oasis. In the two climate change scenarios, pomegranates, the most important tree crop, received insufficient chilling in 13% and 75% of years, respectively. While production of most traditional fruit trees is marginal today, with trees barely fulfilling their chilling requirements, such production might become impossible in the near future. Similar developments are likely to affect other fruit production regions around the world.

Efeito do extrato de alho na quebra de dormência de gemas de videiras e no controle in vitro do agente causal da antracnose (Elsinoe ampelina Shear)

Considerando a redução ou eliminação do uso de substâncias sintéticas que preconizam os sistemas sustentáveis de produção de frutas, este trabalho teve como objetivo a busca de novas alternativas para a quebra de dormência e o controle de doenças em videiras. Estacas de videira contendo uma gema foram pulverizadas com os seguintes tratamentos: 1) testemunha; 2) OV (óleo vegetal) 1%; 3) extrato de alho (EA) 3%; 4) EA 3% + OV 1%. Posteriormente, as estacas foram mantidas em câmara de crescimento (25±2.5ºC) por 56 dias. O único tratamento que estimulou a brotação das estacas de videira cv. Isabel Precoce foi o EA 3% + OV 1%, que atingiu 35% de brotação, diferindo estatisticamente dos tratamentos- testemunha (12,5%), OV 1% (17,5%) e EA 3% (15,0%). Provavelmente, o estádio de endodormência profunda das gemas, após apenas 90 horas de frio ( < 7,0ºC), impediu melhores resultados dos tratamentos para quebra de dormência. Três experimentos, foram conduzidos in vitro, com diferentes doses de extrato de alho, com o objetivo de avaliar o controle do fungo Elsinoe ampelina. Em todos os experimentos, houve efeito quadrático no crescimento micelial, sem ter havido diferenças entre os tratamentos com extrato de alho, evidenciando o seu efeito fungicida, mesmo na dose mais baixa de EA (0,0615%).

Exploring options for farm-level strategic and tactical decision-making in fruit production systems of South Patagonia, Argentina

In South Patagonia, Argentina, sweet cherry is the main fruit-tree crop grown for export, resulting in a highly seasonal labour demand. Managers of deciduous perennial fruit orchards must consider both biological and economic relationships in selecting crop species and orchard design. This makes decisions at the farm-level extremely complex, as especially in such perennial crops, strategic (‘what to plant’, ‘with which technology’ and ‘how much area of each activity’, i.e. the final design) and tactical (‘when, what and how to plant in time’, the pathway to the planned farm) decisions have a long-term effect. The objective of this study was to explore the consequences of different strategic and tactical decisions at farm scale in fruit production systems of South Patagonia, considering the variation in interests and aims of different stakeholders, and using a sensitivity analysis to evaluate the consequences of possible changes in external conditions. A dynamic farm-scale optimization model called OPTIFROP was developed to generate alternative farm development plans, by allocating, in the course of the time horizon of the run, production activities to different land units, while optimising different objective functions, subject to several constraints. Although time-dependent, dynamic, mathematical programming models for analysing farming systems have been described in literature, the dynamic aspects of long-term decision-making in orchard design and their impact on the sequential (annual) nature of orchards in different growth phases (i.e. medium-term decision-making), need a higher time-staged dynamic approach with a staircase matrix structure. The model includes two objective functions at farm level: (1) maximization of the present value of cumulative financial result, which is the main objective for growers, and (2) maximization of cumulative farm labour, which is an objective often mentioned by policy makers. The inter-months deviation for labour demand (during the period of high labour demand, November–April) was included as an upper-bound. Input and output coefficients for the land use options considered in OPTIFROP were quantified using the Technical Coefficient Generator FRUPAT. Model results indicated that the present value of cumulative financial result and the cumulative farm labour are conflicting to a very limited extent. Timing and feasibility of implementing certain combinations of production technologies are affected by resource endowments and initial conditions, but these factors do not influence land use selection in the long term. Land use selection is driven by the objectives of the stakeholders. OPTIFROP showed that, through introduction of alternative crops, substantial reductions in labour peaks in the period November–April could be achieved with a relatively small reduction in farm income. The sensitivity of the model solution to the cherry price suggests that the fruit production sector of South Patagonia should pay more attention to the robustness of their land use plans and take preventive measures to avoid being caught by a possible crisis due to changes in the context.

Influência de sistemas de produção sobre a ocorrência de inimigos naturais de afídeos em pomares de pessegueiros em Araucária-PR

A pressão da sociedade tem forçado a adoção de sistemas de produção de frutas mais sustentáveis e de menor impacto ambiental. O objetivo deste trabalho foi verificar a influência dos sistemas de produção de Boas Práticas Agrícolas (BPA) e Convencional (PC) sobre a diversidade de inimigos naturais de afídeos presentes em seis pomares de pessegueiros no município de Araucária-PR, de julho de 2005 a setembro de 2006. O levantamento do número de inimigos naturais foi realizado por meio de cinco métodos de amostragens: visual em plantas de pessegueiros e em plantas invasoras; armadilhas Möericke; funil e adesivas. No sistema BPA, foram coletados mais espécimes de inimigos naturais (53%), em relação aos pomares PCs (46%), havendo a ocorrência, em ambos, de predadores das famílias Syrphidae, Coccinellidae e Chrysopidae e parasitóides da ordem Hymenoptera. Do total de inimigos naturais coletados, verificou-se a ocorrência de maior quantidade de predadores de afídeos.

Qualidade de cajus-de-mesa obtidos nos sistemas de produção integrada e convencional

O cajueiro (Anacardium occidentale L.) é uma planta de grande importância econômica para o Nordeste brasileiro, pela diversidade de produtos proporcionados pelo fruto e pedúnculo e pela quantidade de empregos gerados. Apesar disso, inexiste uma padronização nos sistemas de produção empregados, com reflexos negativos na produção e qualidade da matéria-prima destinada ao consumo in natura e à indústria. A conversão dos sistemas de produção vigentes para o sistema de produção integrada poderá contribuir para atenuar esse quadro. O objetivo deste trabalho foi comparar os sistemas de produção integrada e convencional para cajueiro-anão precoce quanto à qualidade do pedúnculo. O experimento foi instalado em um pomar comercial, localizado no município de Beberibe (CE), numa área de aproximadamente 1,0 ha, onde foram desenvolvidos os sistemas de Produção Integrada (PI) e Convencional (PC). Cada um ocupou uma área de 0,5 ha, separados entre si por uma bordadura composta de cinco fileiras de plantas. No sistema PI, foram aplicadas as práticas recomendadas nas Normas Técnicas de Produção Integrada de Caju. No PC, foram aplicadas as práticas comumente utilizadas pelo produtor. Foram avaliados cor da película, firmeza de polpa, sólidos solúveis totais (SST), acidez total titulável (AT), teor de vitamina C e pH. Para essas variáveis, foram estimadas médias a partir das 12 amostras obtidas nos dois tratamentos, que foram comparadas, utilizando-se do teste t (P<0,05). Verificou-se, para as variáveis AT e teor de vitamina C, que as médias obtidas no sistema PI foram significativamente superiores às do PC. Quanto ao pH, observou-se diferença significativa entre as médias obtidas nos sistemas, sendo o valor obtido no PC superior ao do PI. Os cajus produzidos no sistema de produção integrada apresentaram melhor qualidade.

Organic Apple Production in Two Humid Regions: Comparing Progress in Pest Management Strategies in Iowa and New Zealand

By 2003, organic apple [Malus sylvestris (L.) Mill var. domestica (Borkh.) Mansf.] production had increased to 5626 ha in the United States and to 2964 ha in New Zealand by 2002. Common problems facing organic apple growers in the humid regions of New Zealand and the United States include effective management strategies for apple scab [Venturia inaequalis (Cooke)] and insect pests. Experiments conducted in Iowa in 2003–2004 demonstrated the effectiveness of a kaolin clay- and spinosad-based insecticide program in maintaining codling moth [Cydia pomonella (L.)] damage levels to less than 5% in the scab-resistant cultivars Enterprise, Liberty, Redfree, and Gold Rush. Similar pest management systems have been developed in New Zealand to comply with export standards and quarantines. The use of codling moth granulosis virus and a spinosad-based insecticide have led to reduced pest pressure and to an increase in organic exports with a 41% premium price over conventional apples. However, an association between spinosad use and woolly apple aphid [Eriosoma lanigerum (Hausmann)] population increase was observed in organic orchard surveys in 2006. An alternative to spinosad applications, insect disinfestation through controlled atmosphere (CA) treatment, was investigated to control quarantined pests and to extend the storage potential of scab-resistant cultivars. A CA treatment of 9 weeks of 2% O2 and 2% CO2 at 0.5 °C was determined to maintain firmness ratings to export standards in CA-stored, scab-resistant ‘Pinkie’ apples and to decrease internal ethylene concentration by 84% compared with apples stored in air. In addition, new scab-resistant cultivars with ‘Pinkie’ background under development in New Zealand show promise for organic production in humid regions. Few fruit quality differences were determined between ‘Pinkie’ fruits from integrated fruit production and organic production systems, although premium prices exist only for certified organic apples.

Integrated freshwater aquaculture, crop and livestock production in the Mekong delta, Vietnam: Determinants and the role of the pond

Promotion of integrated aquaculture with agriculture, including crops and livestock (IAA-farming), requires consideration of both bio-physical and socio-economic contexts. The major factors influencing the adoption of IAA-farming by households at three sites in the Mekong delta were identified. Special attention was given to the multiple roles ponds play in IAA-farming systems. Information was collected through semi-structured interviews and discussions with focus groups and key individuals. Data were analyzed using multivariate factor analysis, analysis of variance or participatory ranking methods. Three major IAA-systems were identified: (1) low-input fish farming integrated with intensive fruit production (system 1), (2) medium-input fish farming integrated with less intensive fruit production (system 2), and (3) high-input fish farming integrated with less intensive fruit production (system 3). System 1 was commonly practised in a rural fruit-dominated area with fertile soils, while systems 2 and 3 were more evident in peri-urban rice-dominated areas with less fertile soils. In the study area, only 6% of poor farmers adopted IAA-farming, while this was 42% for intermediate and 60% for rich households. Richer farmers tended to intensify fish farming and seek a more commercial orientation. The major factors why farmers did not start aquaculture were the inappropriateness of technology, insufficient land holding or poor access to extension services, limited farm management, and through a fear of conflicts associated with pesticide use on crops. The main motivations for practising IAA-farming included increased income and food for home consumption from the available farm resources while reducing environmental impacts. Further improvements to IAA-systems can be realized by strengthening nutrient recycling between different IAA-system components while enhancing farming output and safeguarding the environment.

Distribución espacio temporal y daño ocasionado por Pestalotia spp. en frutos de guayaba

A fin de determinar la distribución espacio-temporal del hongo Pestalotia spp., así como los grados de daño físico y alteración química que ocasiona en los frutos de guayaba (Psidium guajava L.) en la Hoya del Río Suárez (Colombia), se evaluaron frutos con síntomas de la enfermedad procedentes de 104 fincas productoras en las que se presentan pérdidas económicas a causa de las costras sobre el fruto. La distribución temporal se indagó en 16 fincas del municipio de Vélez (Santander) durante cuatro períodos climáticos anuales. El daño físico se estableció mediante el índice de severidad (%), teniendo en cuenta madurez, sistema de producción, altitud, densidad de siembra y edad de los árboles. Para detectar posibles alteraciones químicas en frutos maduros afectados se analizaron las variables sólidos solubles totales (%), azúcares reductores (%) y acidez titulable (% de ácido cítrico). La distribución espacial, evaluada en época de verano (enero y febrero), determinó la presencia del patógeno en 102 de las 104 fincas estudiadas. En los municipios de Puente Nacional, Jesús María y Guavatá se presentó la mayor incidencia en frutos (≥85%), mientras que en Oiba y Guadalupe fue la más baja (36,7%). En los períodos de transición invierno/verano (julio) y verano/invierno (marzo) ocurrieron las mayores incidencias con 93,1 y 90,6%, respectivamente. La severidad de la enfermedad fue mayor en frutos pintones y maduros, en el sistema guayaba x café, entre 1.901 y 1.960 m.s.n.m. y en densidades superiores a 490 árboles por hectárea. Se constató que Pestalotia spp. no causó alteraciones químicas en el fruto.

(162) Multi-level Comparisons of Organic (OFP) and Integrated Fruit Production (IFP) Systems for `Liberty' Apple in a New York Orchard

Apple growers in New York lack the tools to produce high quality fruit for the organic or IFP marketplace. We are systematically evaluating OFP and IFP systems for pest control efficacy, fruit and soil quality, environmental impacts, and economic sustainability, in an orchard of disease-resistant `Liberty' on M.9 rootstock. The OFP system follows USDA-NOP standards and the IFP system follows newly developed NY IFP standards. In the first year of this study (2004), both systems were equally productive, but variable costs for OFP were twice that of IFP, due to 11 kaolin applications, while returns were comparable. In 2005, OFP yields were 25% greater than IFP yields, but 30% of OFP fruit was unmarketable largely due to insect damage. This loss, plus small fruit size, resulted in OFP returns of $5432 per hectare, about half the IFP returns. With only four kaolin applications in 2005, OFP costs were $2437 per hectare, marginally greater than the $2083 per hectare costs for IFP apples. Harvest maturity indices were similar and peak fruit quality was attained in both systems in early Oct. In 2004, consumer panelists could not detect differences between fruit from the two systems, but in 2005 panelists rated OFP apples as sweeter, more tart, better flavored, and more acceptable overall. Antioxidant activity, total phenolics concentrations, and mineral content of apples were similar between systems in both years. Values for all essential plant nutrients, organic matter content, pH, and CEC were also equivalent in each system both years. Cultivation was likely responsible for lowering the bulk density, soil strength, and aggregate stability of the OFP top soil in 2005. While OFP remains very challenging, IFP can be implemented successfully in New York orchards.

FRUPAT: A TOOL TO QUANTIFY INPUTS AND OUTPUTS OF PATAGONIAN FRUIT PRODUCTION SYSTEMS

A software called FRUPAT was developed for calculating input and output coefficients (Technical Coefficients) of fruit production systems in South Patagonia. FRUPAT combined locations (Rio Chubut valley; Sarmiento valley; Los Antiguos valley; Rio Chico valley), edaphic environment (good quality soil with water-table depth exceeding 2 m; good quality soil with water-table depth between 1 and 2 m; low water holding capacity soil without water-table influence), fruit-tree crops (sweet cherry; plum; peach; apple; walnut), training systems (tatura; central leader; vase), irrigation systems (drip; furrow) and frost control systems (sprinkler irrigation; heating; passive) that provided 1080 multi-annual fruit production activities. Parameters have been identified as default values and most of those can be easily modified by the user. Relevant inputs and outputs can be estimated, such as gross value of product, expenditures, financial result, biocide use, N-fertiliser surplus and labour. As an example of how FRUPAT can be used, some results are presented for a single physical environment (good quality soil with water-table depth exceeding 2 m, in the Rio Chubut valley) using sprinkler irrigation as frost control method. First, 5 crops under a single production technique (vase with furrow irrigation) are compared in terms of their monetary technical coefficients. Subsequently, results of sweet cherry under different production techniques (3 training systems with 2 irrigation systems) are presented. Finally, the time course of gross value of product, total expenditures, financial result and cumulative financial result are analyzed for a single activity (sweet cherry, trained as tatura under drip irrigation). FRUPAT may be used as a stand-alone tool for simple analysis as demonstrated here or as an intermediate step for linear programming

Stoßdetektor zum Implantieren in empfindliche Früchte

Significant criteria for evaluating damage risks for perishable fruit are necessary to improve quality management. Currently used certification instruments for fruit production systems do not contain methods and means suited to satisfy the specific requirements for fruit quality and safety. A newly developed innovative impact detector for implantation into perishable fruit and for real-time data transmission and processing could be helpful in overcoming present difficulties in evaluating mechanical impacts according to specific fruit properties.

Effects of Organic and Plant Residue Quality and Orchard Management Practices on Decomposition Rates of Residues

In grassed-down fruit orchards, understorey plant residues have been shown to constitute an important source of soil organic matter and plant nutrients in biological and integrated fruit production systems. Under these systems, contrasting understorey plant residue types and different orchard treeline management practices may affect the decomposition rates and nutrient release from these residues. Although a recent field study has found these factors to be important, their detailed comparisons have not been conducted. In the present study, two incubation experiments were conducted concurrently in the laboratory at 25°C for 110 days. Experiment I examined the relationships between residue quality characteristics and decomposition rates of a range of six organic residues and three understorey plant residues from biological and integrated fruit orchard systems. A control treatment without added residue was also studied. All residues were analyzed for important biochemical quality factors. Experiment II evaluated the effects of simulated orchard treeline management practices, involving adding the above three orchard understorey plant residues to each of three different surfaces consisting of bare soil, pea straw mulch and pine bark mulch. Plots of cumulative CO2-C production of residues fitted an exponential relationship of C = C 0(1 − e− kt ) where k is the cumulative CO2-C decomposition rate constant and C 0 the asymptotic cumulative maximum C mineralized. This relationship accounted for 97 to 99% of the variations in CO2-C production in all residues except sawdust (78%) and pine bark (89%). No significant differences occurred in k and C 0 values of the three orchard understorey plant residues. These values were similar to those of the clover residue but were significantly higher than those of pea straw, barley straw, spent mushroom compost, pine bark and sawdust. Results of all residues were significantly correlated with cellulose, lignin, lignin + polyphenol contents, cellulose:N, lignin:N, (lignin + polyphenol):N, and C:N but not polyphenol content. Decomposition rates of understorey residues were most rapid on bare soil compared to mulched surfaces and were significantly lowest on pea straw surface.