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The effect of deficit irrigation and in situ moisture conservation in kiwifruit cv. Allison vines was studied during the years 2011 and 2012 in the Department of Fruit Science, Dr. Y. S. Parmar University of Horticulture and Forestry, Solan, HP, India. Soil moisture content and frequency of irrigation were investigated in kiwifruit in response to deficit irrigation and in situ moisture conservation techniques. Seven treatments viz., irrigation at 80 per cent Field Capacity (T1), 60 per cent Field Capacity (T2) and 40 per cent Field Capacity (T3), 60 per cent Field Capacity (FC) plus grass mulch (T4) or black polythene (T5) and 40 per cent FC plus grass mulch (T6) or black polythene (T7) were applied from March to October with three replications in Randomized Block Design (RBD). During the year 2011, the soil moisture content under kiwifruit vines was highest under the treatment T1 (15.3, 16.9), followed by T5 (15.2, 16.8) and T4 (14.9, 16.6) at 30 cm and at 60 cm soil depth, respectively. Whereas, during the year 2012, the soil moisture content under kiwifruit vines was highest under the treatment T1 (14.9, 16.4), followed by T5 (15.0, 16.3) and T4 (14.6, 16.1) at 30 cm and at 60 cm soil depth, respectively. However, the least soil moisture content was, however, observed under T3 (11.0, 12.8) at 30 cm and 60 cm soil depth, respectively, during the year 2011, similarly, during the year 2012, the least soil moisture content was also observed under T3 (10.6, 12.7) at 30 cm and 60 cm soil depth, respectively. The frequency of irrigation was highest under T1 (16 irrigations) followed T2 (10 irrigations) while the least was recorded under T6 and T7 (7irrigations). Total numbers of irrigations applied were reduced from 16 (under T1) to 8 (under T5). The use of black plastic mulch may be beneficial as it helped to conserve moisture under DI regime which is comparable to those in well irrigated vines. It may also reduce the high irrigation requirement of kiwifruit in areas where sufficient water is not available. [ABSTRACT FROM AUTHOR]

A field study was undertaken to extrapolate the impact of foliar application of potash and its spray schedule on yield and physical and chemical parameters of sweet orange cv. Jaffa at experimental orchard, Department of Horticulture, CCS Haryana Agricultural University, Hisar. The results revealed that foliar application of KNO3 at both the doses (2 and 4%) was found significantly or marginally better than K2SO4 (1.5 and 3.0%) and control (water spray) in increasing the juice content. Peel content, peel thickness and rag content was found to be influenced significantly due to different treatments on K and its spray schedule. Minimum rag content (38.11%) was recorded with foliar application of KNO3 at the rate of 4% and maximum with control. Ascorbic acid and acidity were found maximum with two foliar applications of KNO3 at the rate of 4% in the last week of April and August. Foliar application of KNO3 at the rate of 4% was found most effective in increasing yield of sweet orange over control and other K treatments. Spray of K in the last week of April, May and August was found superior in increasing yield closely followed by two sprays in the last week of April and August. The findings signify the importance of K spray in enhancing yield and quality of sweet orange under semi-arid north western conditions of India. [ABSTRACT FROM AUTHOR]

Knowledge and monitoring of the grapevine phenology during the season are important requirements for characterization of productive regions, climate change studies and planning of various production activities at the vine field scale. This work aims at studying the spatial variability of grapevine phenology at the within field scale. It was conducted on two fields, one of cv Cabernet Sauvignon of 1.56 ha and the other of cv Chardonnay of 1.66 ha, both located in Maule Valley, Chile. Within each vine field, a regular sampling grid was designed, to carry out weekly measurements of phenology and maturation. The main results show that there is a significant spatial variability in the phenological development and maturation at the within field scale for both fields. This variability is spatially organised and temporally stable from the beginning of the season (post-budburst) to harvest and over the years. A cluster analysis allowed us to define two clearly contrasted zones in terms of phenology and maturation in both fields, explained by the microclimate. The magnitude of difference between zones varied from 4 to 9 days depending on phenological stages and from 5 to 43 days for maturation. These differences are similar and comparable to that observed at larger scales or under scenarios of climate change. These results highlight the necessity to better take into account this variability to improve sampling and to base decisions of production activities (spraying, harvest, pruning, etc.) application on more relevant information. Further investigations should determine the environmental factors that determine the observed spatial variability. [ABSTRACT FROM AUTHOR]

Wild blueberry ( Vaccinium angustifolium Ait.) fields in the north east Canada are naturally grown in a course textured thin layer of soil and below this layer is a soilless layer of gravel. The root zone depth of this crop varies from 10 to 15 cm. Investigating the depth to the gravel layer below the course textured soil is advantageous, as it affects the water holding capacity of the root zone. Water and nutrient management are the two primary determinants of crop yield and the amount of leaching. The objective of this study was to estimate the depth to the gravel layer using DualEM-2 instrument. A C++ program written in Visual Studio 2010 was used to develop mathematical models for estimating the depth to the gravel layer from the outputs of DualEM-2 sensor. Two wild blueberry fields were selected in central Nova Scotia, Canada to evaluate the performance of DualEM-2 instrument in estimating the rootzone depth above the gravel layer. The mid points of squares created by grid lines were used as the sampling points at each experimental site. The actual depth to the interface was measured manually at selected grid points ( n = 50). The apparent ground conductivity (EC) values of DualEM-2 were recorded and the depth to the interface was estimated for the same sampling points within the selected fields. The fruit yield samples were also collected from the same grid points to identify the impact of the depth to the gravel layer on crop yield. After calibrations, comprehensive surveys were conducted and the actual and estimated depths to the interface were established. The interpolated maps of fruit yield, and the actual (z) and estimated ( $$ {\text{z}}_{\text{in}}^{*} $$ ) depths to the interface were created in ArcGIS 10 software. Results indicated that the z was significantly correlated with $$ {\text{z}}_{\text{in}}^{*} $$ for the North River ( R = 0.73; RMSE = 0.27 m) and the Carmel ( R = 0.45; RMSE = 0.20 m) sites. Results revealed that the areas with shallow depth to the gravel layer were low yielding, indicating that the variation in the depth to the gravel layer can have an impact on crop productivity. Non-destructive estimations of the depth to the gravel layer can be used to develop erosion control strategies, which will result in an increased crop production. [ABSTRACT FROM AUTHOR]

This study aims to discuss and explain how to deal with the analysis of experiments conducted in completely randomized design (CRD) and subdivided into double factorial with additional treatment in the plot. In addition it was illustrate the discussion by analyzing data from an experiment on post-harvest of Niagara grapes. The sums of squares for each source of variation are presented, while discussing how the additional treatment affects the whole variation. Niagara grapes were treated in the pre-harvest with three preservatives (calcium chloride, calcium nitrate and calcium lactate) at 0%, 0.5%, 1% and 2% and stored for 0, 10, 20 and 30 days. All the preservatives evaluated at 0% represented the control (additional) treatment. [ABSTRACT FROM AUTHOR]

Background and Aims Interactions are the main causes of complexity in field experiments; however, no studies have combined water and temperature regimes in field-growing vines. Here we assessed grape and wine attributes from a field trial where these factors were directly manipulated. Methods and Results The experiment consisted of Shiraz vines grown in a 22 factorial experiment with two temperature (control and heated) and two water regimes (deficit and irrigated) during two seasons (2010/11 and 2011/12). The sensory and compositional characteristics of grapes and wines were assessed in both seasons, whereas a detailed profile of the phenolic substances was determined by spectrophotometry in 2011/12. We found additive effects (i.e. lack of interaction) between temperature and water for berry mass and components, fruit composition (titratable acidity and pH), grape phenolic substances (12.5% ethanol-extracted and most of the 70% acetone-extracted), wine phenolic substances (chemical age 2), and wine sensory traits (floral aromas and berry flavours). Significantly, previously unrecorded interactions between temperature and water were found for grape phenolic substances (70% acetone-extracted skin and seed tannins and total phenolic substances per berry), wine phenolic substances (colour density, tannins and phenolic substances) and wine sensory traits (floral aromas, cooked fruit flavours and tannin structure). Conclusion The effect of water deficit leading to colourful and flavoursome wines rich in phenolic substances may not be held under high temperature. Significance of the Study Our study anticipates the drier and hotter climate of the Barossa Valley, and provides industry with indications of a shift in wine profiles that would require technological innovation to maintain the identity of Barossa Shiraz. [ABSTRACT FROM AUTHOR]

BACKGROUND Flowers, flowering and fruit set are key determinants of grapevine yield. Currently, practical methods to assess the flower number per inflorescence, necessary for fruit set estimation, are time and labour demanding. This work aims at developing a simple, cheap, fast, accurate and robust machine vision methodology to be applied to RGB images taken under field conditions, to estimate the number of flowers per inflorescence automatically. RESULTS Ninety images of individual inflorescences of Vitis vinifera L. cultivars Tempranillo, Graciano and Carignan were acquired in the vineyard with a pocket RGB camera prior to flowering, and used to develop and test the 'flower counting' algorithm. Strong and significant relationships, with R2 above 80% for the three cultivars were observed between actual and automated estimation of inflorescence flower numbers, with a precision exceeding 90% for all cultivars. CONCLUSION The developed algorithm proved that the analysis of digital images captured by pocket cameras under uncontrolled outdoors conditions was able to automatically provide a useful estimation of the number of flowers per inflorescence of grapevines at early stages of flowering. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND The aim of this study was to determine the effect of three factors directly related to the amino acid content of grapes and their interaction. These three factors were vintage, maturity degree and irrigation. The evolution of amino acid was also assessed during the winemaking along with the effect of maturity and irrigation on the biogenic amine formation. The grapes used for this study were of the Verdejo variety. RESULTS The results indicated that there was a strong vintage effect on amino acid content in grapes, which seemed to be clearly related to climatic conditions. The effect of maturity on amino acid content depended on vintage, irrigation and the amino acid itself although it was observed that irrigation caused the increase of most amino acids present in the berry. Irrigation did not affect the evolution of nitrogen compounds during the alcoholic fermentation process but the maturity degree in some of the amino acids tested did so. No direct relationship could be established between irrigation or maturity degree and biogenic amines. However, it should be noted that the biogenic amine content was very low. CONCLUSIONS Vintage has a strong effect on the amino acid content in grapes which appears to be related to weather conditions. No direct relationship has been found between irrigation or maturity degree and biogenic amines content. Furthermore, it is noted that biogenic amine content found in final wines was very low. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Dissipation behavior and hazard assessment of the fungicide fenhexamid applied to grapes were investigated under climatic conditions in Egypt. Fenhexamid residues were extracted from grape samples with ethyl acetate. The extract was cleaned up by QuEChERS (quick, easy, cheap, effective, rugged, and safe) method, and determined by gas chromatographic method (GC-μECD). The average recoveries ranged between 94.2% and 99.4% with associated relative standard deviation not exceeding 12%. The estimated limit of quantification for fenhexamid was 0.1 mg/kg. The field results showed that fenhexamid dissipated rapidly from grapes and had a half-life of approximately 4.21 days. Hazard assessment was evaluated by using the hazard quotient (HQ). Data showed that the HQ value was significantly less than HQ = 1. Results indicate that hazard of fenhexamid use in grape even at 1.5-fold higher than recommended dosage was negligible to humans. This study could provide guidance for safe and reasonable use of fenhexamid in grapes and prevent health problems to consumers. However, further hazard assessment studies are needed to ascertain the hazard of fenhexamid residues on grape to vulnerable groups, including children, pregnant women, and elderly consumers. [ABSTRACT FROM AUTHOR]

The dissipation of diazinon (O,O-diethyl O-2-isopropyl-6-methylpyrimidin-4-yl phosphorothioate) in grapes was investigated to determine its pre-harvest interval (PHI). Diazinon was applied to grapes at the recommended dosage (0.9 g a.i. L−1) and twice the recommended dosage (1.8 g a.i. L−1) three times, at the fruit formation stage, the sour stage, and the ripening stage, in a field trial with three replications. Samples were taken at 0, 1, 2, 4, 7, 11, 15, 20, 26 and 32 days after spraying. The residue was extracted using a water/methanol/acetonitrile (1:1:1, v/v/v) solvent and solid phase extraction was employed for cleanup. Quantitative analysis was performed using a gas chromatograph equipped with a nitrogen-phosphorus detector. The dissipation trend for the recommended dosage and twice the recommend dosage followed the simple first-order kinetic model (SFOK) (DT50= 3.29 days, DT90= 11 days, PHI = 13.5 days) and first-order double-exponential decay (FODED) model (DT50= 1.08 days, DT90= 5.82 days, PHI = 15.29 days), respectively. The average initial deposit of diazinon at the recommended dosage was 9.04 mg kg−1and for twice the recommended dosage was 27.38 mg kg−1and it dissipated rapidly within days of spraying. [ABSTRACT FROM PUBLISHER]

Abstract: Practices that enhance abundance and diversity of generalist predators are often employed with the objective of improving biological control of insect pests. Ground beetles and other predators can prey on blueberry maggot, an important pest of blueberries, when mature larvae pupate in the ground. We conducted mesocosm and field experiments to determine if Pterostichus melanarius, a common predatory ground beetle, lowers maggot numbers in compost mulch or when predator and alternative prey abundances are manipulated. At background (field) densities of alternative prey, increasing densities of P. melanarius did not significantly reduce pest numbers in mesocosms containing compost or soil. When alternative prey were removed from compost, beetles reduced pest numbers by up to 35%. In field experiments, maggot numbers were higher when beetles and other predators were excluded from soil plots, but beetle exclusion had no effect in compost plots where both predator and alternative prey numbers were high. Our results indicate that there can be some reduction of blueberry maggot by P. melanarius and other potential predators when there are few alternative prey. However, despite attracting large numbers of predators compost mulch did not lead to a significant reduction in blueberry maggot; in fact, the high abundance of alternative food associated with compost appeared to interfere with beetle predation on blueberry maggot. [Copyright &y& Elsevier]

Determination of optimum rates of potassium (K) for high citrus production with great qualitative traits is of both agricultural and economical significance, particularly when performing long-term experiments. A five-year field experiment was conducted in the Citrus Research Center of Tonekabon, Iran in a silty clay loam. The objectives were to: 1) to apply different rates of K fertilizer and determine the optimum rates for citrus high production, and 2) to evaluate the effects of K fertilization on the fruit quantitative and qualitative traits for the production of tasty and great quality fruits for fresh or long consumption. Fifteen-year citrus trees were fertilized with five rates of potassium at control, 750, 1500, 2250 and 3000 g tree-1 on the basis of a completely randomized block design in five replicates. Fruit parameters were determined. Potassium significantly increased fruit yield and qualitative traits at the optimum amount of 1500 g tree-1. [ABSTRACT FROM AUTHOR]

The article presents the European Prospective Investigation unto the medical prevalence of fruits and vegetables to prevent the development of colorectal cancer. The prospective investigation examines the self-reported usual consumption of fruit and vegetables among women and men and uses a Cox proportional hazard model to estimated the adjusted hazard ratios (HRs). It suggests that high consumption of fruit and vegetables reduces the risk for colon cancer.

Some important olive cultivars (Kilis yağlık, Halhalı, Karamani, Haşebi, Nizip yağlık) in East Mediterranean Area were studied. Olive fruits were processed on a low-scale mill equipped with a basket centrifuge. Basic quality parameters, the content of total polyphenols, o-diphenols, oxidation stability (Rancimat) and antiradical activity [1,1-diphenyl-2-picrylhydrazyl (DPPH)] were determined in oil samples. The highest induction period (IP) was 36.42 h, found in the Halhalı cultivar (from Gaziantep province), which also had strong radical scavenging activity (RSA) (96.72% in methanol:water extract and 94.91% in total oil) in all samples. The total phenol and o-diphenol content for this cultivar were 495.42 and 76.89 mg caffeic acid/kg oil, respectively. The oxidation stability and antiradical activity of the Kilis yağlık cultivar (from Kilis province) was very poor when compared to other cultivar (IP; 10.40 h, RSA in methanol: water extract; 30.94%, RSA in total oil; 52.31%). In addition total phenol and o-diphenol content for this cultivar were 38.31 and 5.03 mg caffeic acid/kg oil, respectively. [ABSTRACT FROM AUTHOR]

A non-contact, non-destructive, and rapid method of detecting freeze-damaged oranges based on ultraviolet (UV) fluorescence of the peel oil constituents visible on the peel surface was investigated. The visual appearance is different from oleocellosis in that freeze-damaged oranges exhibit a fine pattern of 1–2mm bright yellow dots on the peel when viewed under longwave UV light. Visual and machine vision-based methods were evaluated to determine their ability to detect freeze damage in Californian navel oranges (Citrus sinensis L. Osbeck) subjected to laboratory simulated freeze conditions of −7°C for 0, 8, or 16h periods. The study focused on the period within the first few days (i.e., prior to fruit dehydration) after a freeze event has occurred because there are currently no rapid, objective, and non-destructive methods of freeze damage detection available for use during that time period. Using the USDA segment cut method to determine the presence of internal freeze damage, the classification rates for both UV fluorescence methods varied with the level of freeze damage. Using machine vision, a classification accuracy of 87.9% was obtained for unfrozen and moderately or severely frozen fruit, dropping to 64.4% for fruit with low levels of freeze damage. UV fluorescence shows promise for both visual inspection using existing black light inspection rooms or for automation using on-line machine vision techniques for separating freeze-damaged fruit subjected to moderate or severe freeze conditions. [Copyright &y& Elsevier]

A survey of blueberry growers determined the extent of rain-related splitting fruit on blueberry production in Mississippi and Louisiana. Growers were asked to approximate (1) the number of acres or plants of each cultivar on their farm (2) the severity rating (1 = No splitting-5 = Severe splitting) of each cultivar, and (3) the percent of berries lost to rain-related splitting. Among the 3 most widely planted cultivars, 'Premier' exhibited the least splitting (1.2 rating) followed by 'Climax' (2.2) and 'Tifblue' (3.1) had the most split fruit. [ABSTRACT FROM AUTHOR]