• Authors:
    • Mulas, M.
    • Deidda, B.
    • Zurru, R.
  • Source: Acta Horticulturae
  • Issue: 928
  • Year: 2012
  • Summary: Pruning of Clementine requires a lot of time: more than 50 days of work per hectare in the traditional forms of orchard management. Because of the high cost and the lack of specialised workers, we observe a general tendency to delay the frequency of pruning in the citrus orchards. On the other hand regular pruning is of fundamental importance to have good fruit quality, to maintain health status of the orchard, and to store their regular productivity. In order to optimise the Clementine pruning technique, reduce the time of execution and maintain a good level of yield of better quality a field experiment was designed. In 1996 a commercial orchard of 'SRA 63' Clementine located in Southern East Sardinia was selected for the experiment. Plants were grafted on 'Troyer' Citrange, twenty-year-old, spaced 7*5 m, shaped to globe, over 4 m in height, and showed an excessive number of main branches (about 7-8 per tree) with a dense canopy. The entire orchard was preliminarily submitted to a gradual shape pruning during the first four years. In 2000 two main plots of 72 plants each were designed: (A) pruning every year; and (B) pruning every two years. The orchard was observed for a further period of four years for the following characters: trunk section area; canopy size, working time for pruning; pruned wood weight; fruit yield; fruit size. In both pruning applications (A and B) the canopy was more open and green than in the past, with a improvement of the plant heath status, a reduction of the number of treatments, water for irrigation and fertilizers, less working time for harvest, and with a significant better fruit size and increase of the production value.
  • Authors:
    • Armentano, G.
  • Source: L'Informatore Agrario
  • Volume: 68
  • Issue: 1
  • Year: 2012
  • Authors:
    • Valboa, G.
    • Favilli, F.
    • L'Abate, G.
    • Papini, R.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 140
  • Issue: 1-2
  • Year: 2011
  • Summary: Land use strongly influences soil properties and unsuitable practices lead to degradation of soil and environmental quality. The aim of this study was to assess the impact of different land uses on some chemical properties of soils developed from Pliocene clays, within hilly environments of central and southern Italy. The areas investigated are located in Vicarello di Volterra (Pisa, Tuscany), S. Quirico d'Orcia (Siena, Tuscany) and Soveria Simeri (Catanzaro, Calabria). Within each area different land uses were compared, including a natural ecosystem (Mediterranean bush), a perennial grass or pasture and an intensive crop (wheat, as monoculture or in rotation). The soils were sampled at 0.0-0.1, 0.1-0.2 and 0.2-0.4 m depth and analysed for particle size, pH, bulk density, cation exchange capacity and exchangeable cations, total organic carbon (TOC) and humified carbon (HC) concentrations, organic carbon stock and total N. The stratification ratio of soil organic carbon was calculated to characterize soil organic carbon distribution with depth. At all sites, soil under Mediterranean bush contained the largest amounts of TOC (as both concentration and stock), HC, total N and exchangeable K, together with the highest cation exchange capacity and the lowest pH values. The decrease in soil OC stock with land use change from natural to agricultural ecosystem was 65-85% to 0.1 m depth, 55-82% to 0.2 m depth and 44-76% to 0.4 m depth, with the lowest decrements for perennial grass from S. Quirico and the highest decrement for continuous wheat from Soveria Simeri. Continuous wheat cropping, based on conventional tillage, proved to be the least sustainable land use. At Soveria Simeri, the organic carbon content under pasture was not significantly larger than under wheat cultivation, probably because of grazing mismanagement; however, organic carbon under pasture was more humified. At S. Quirico, the perennial grass resulted in a significant increase in soil organic carbon at the soil surface relative to the wheat cultivation, while at Vicarello no differences were observed between alfalfa/wheat rotation and perennial grass. Our results lead to the questioning of sustainability of intensive cereal farming and uncontrolled grazing in the considered environments, emphasizing the need for greater attention to conservative land managements.
  • Authors:
    • Radicetti, E.
    • Mancinelli, R.
    • Campiglia, E.
    • Marinari, S.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 89
  • Issue: 3
  • Year: 2011
  • Summary: There is not sufficient knowledge concerning the risks involved in NO 3-N leaching in relation to the use of cover crops and mulches. A 2 year field experiment was carried out in a pepper ( Capsicum annuum L.) crop transplanted into different soil management treatments which involved the addition of mulch of three different types of winter cover crops (CC) [hairy vetch ( Vicia villosa Roth.), subclover ( Trifolium subterraneum L.), and a mixture of hairy vetch/oat ( Avena sativa L.)], and an un-mulched plot. At the time of CC conversion into mulch, the hairy vetch/oat mixture accumulated the highest aboveground biomass (5.30 t ha -1 of DM), while hairy vetch in pure stand accumulated the highest quantity of N (177 kg ha -1) and showed the lowest C/N ratio (12). The marketable pepper yield was higher in mulched than in conventional (on average 33.5, 28.9, 27.7 and 22.2 t ha -1 of FM for hairy vetch, subclover, hairy vetch/oat mixture, and conventional, respectively). Generally, the NO 3-N content of the soil was minimum at CC sowing, slightly higher at pepper transplanting and maximum at pepper harvesting (on average 15.2, 16.8, and 23.3 mg NO 3-N kg -1 of dry soil, respectively). The cumulative leachate was higher during the CC period (from October to April) than the pepper crop period (from April to September), on average 102.1 vs 66.1 mm over the years, respectively. The cumulative NO 3-N leached greatly depended on the type of mulch and it was 102.3, 95.3, 94.7, and 48.2 kg ha -1 in hairy vetch, subclover, hairy vetch/oat mixture, and conventional, respectively. A positive linear correlation was found between the N accumulated in the CC aboveground biomass and the NO 3-N leached during pepper cultivation ( R2=0.87). This research shows that winter legume cover crops, especially hairy vetch in pure stand, converted into dead mulch in spring could be used successfully for adding N to the soil and increasing the yield of the following pepper crop although the risks of N losses via leaching could be increased compared to an un-mulched soil. Therefore when leguminous mulches are used in the cultivation of a summer crop, appropriate management practices of the system, such as a better control of the amount of irrigation water and the cultivation of a graminaceous or a cruciferous catch crop after the harvesting of the summer crop, should be adopted in order to avoid an increase in NO 3-N leaching.
  • Authors:
    • Scicolone, B.
    • Consoli, S.
    • Capra, A.
  • Source: Acta Horticulturae
  • Issue: 922
  • Year: 2011
  • Summary: Citrus orchards are economically one of the most important crops in South Italy, where climate is semi-arid with scarce rain and high evaporative demand. One way to optimize water resources in this region is to adopt deficit irrigation (DI) strategies, such as regulated deficit irrigation (RDI). In Mediterranean regions, DI criteria have been widely applied and crop physiological responses to water deficit application have been studied in depth, but the profitability of these strategies in commercial orchards is still largely unknown. The objective of this study was to determine the economic feasibility of DI treatment on orange orchards in Sicily (South Italy), by estimating optimum levels of applied water which provide maximum profit under limited resource availability (e.g. land or water). The applied methodology follows the economic analysis on DI suggested by English in 1990. The analysis of the profit/total costs ratio showed that Deficit Irrigation strategies would increase the generated income, thus being more profitable (up to a maximum of 100%) than the current irrigation water supply management in the area.
  • Authors:
    • Lo Giudice, V.
  • Volume: 67
  • Issue: 4
  • Year: 2011
  • Summary: This paper provides information on the behaviour of Clemenrubi, a new clementine selection introduced from Spain, based on field experiences (including the experiments conducted in 2008-10 in Sicily, Italy, on Carrizo citrange rootstock) and existing literatures. Clemenrubi may be a valid selection for the Italian citrus due to its precocious maturation as early as September, but the sunburn and splitting of its fruits must be controlled. Studies in the coming years will be necessary to determine the behaviour of Clemenrubi in different growing conditions. Some suggestions are given to prevent sunburn and splitting of the fruits, including foliar application of calcium nitrate at 2% in June and July, as well as careful management of irrigation and fertilizer application.
  • Authors:
    • Mennone, C.
  • Source: Informatore Agrario
  • Volume: 67
  • Issue: 27
  • Year: 2011
  • Summary: Techniques to increase fruits size of clementine are mentioned, which include fruit thinning and use of plant growth regulators. The developmental stages of clementine fruits are described. Factors affecting fruit size, including genetic factors, variety, fruit number, competition among developing organs (flowers and fruits), external factors (climatic, edaphic (soil) and cultural practices such as pruning, fertilization, irrigation) and application of growth regulators are discussed. Results are presented of trials conducted in Metaponto, Italy, to investigate the efficacy of some plant growth regulators (triclopyr+MCPA and gibberellic acid (ester)) in increasing size and improving colour and quality of clementine fruits.
  • Authors:
    • Bene, C. di
    • Tavarini, S.
    • Mazzoncini, M.
    • Angelini, L. G.
  • Source: European Journal of Agronomy
  • Volume: 35
  • Issue: 3
  • Year: 2011
  • Summary: The introduction of perennials in the Mediterranean crop rotations can have a positive effect on soil organic matter (SOM) concentration, thus improving the long-term sustainability of cropping systems, affected by the progressive degradation in soil fertility. Ramie [ Boehmeria nivea (L.) Gaud.], a perennial herbaceous species used for its high quality bast fibre, has recently received renewed attention for production in Europe due to the increasing natural fibre demand globally. Little attention has been focused on the ramie cultivation management and on its effect on soil chemical characteristics. A long-term field experiment was carried out in Pisa (Central Italy, 43 degrees 40′N; 10 degrees 19′E) since 1996, with the aim to assess the long-term environmental sustainability of ramie in terms of productivity, nutrient balance, soil fertility and SOM pool. The fertiliser management of ramie consisted of 150-100-100 kg N-P-K ha -1 in the establishment year and 150-65-165 kg N-P-K ha -1 year -1 from the second year onwards. Plant nutrient uptake was analysed to optimise the crop mineral nutrition and to evaluate the nutrient balance and the efficiency of fertiliser management. The SOM dynamic was evaluated using the actual investigated data and Henin-Dupuis's equation in order to estimate the organic requirements for SOM equilibrium. Over the 13-year cultivation period, a mean value of 14 Mg ha -1 year -1 of total above-ground dry biomass was obtained. In the 0-30 cm soil depth, SOM, total nitrogen (N), available phosphorus (P), exchangeable potassium (K) and pH varied significantly throughout the cultivation period. SOM increased significantly, from 13.4 g kg -1 to 25.3 g kg -1. A significant correlation between the measured SOM and the cumulative organic matter (OM) inputs ( r2=0.908; P=0.012) was found. The average annual N and P balances were positive (equal to 14 kg ha -1 and 38 kg ha -1, respectively), while the K balance was negative (-57 kg ha -1). The results show that ramie crop has a positive effect on SOM pool, thus representing an interesting sustainable fibre crop for the Mediterranean area.
  • Authors:
    • Ortega-Farias, S.
    • Selles, G.
  • Source: ISHS Acta Horticulturae
  • Issue: 889
  • Year: 2011
  • Summary: These proceedings contain 79 papers on irrigation systems for horticultural crops. Specific topics covered include the following: improvement of water use for agriculture at catchment level under drought conditions; impact of climatic change on irrigated fruit tree production; effects of the irrigation regime and partial root zone drying on grape cv. Vermentino in Sardinia, Italy; effects of canopy exposure changes on plant water status in grape cv. Syrah; water use by drip-irrigated early-season peach trees; soil water content variations as water stress indicator in peach trees; reduction in the number of fruits in peach (T204) due to postharvest deficit irrigation; effects of irrigation management and N fertilizer on the yield and quality of apple cv. Gala; canopy temperature as an indicator of water status in citrus trees; effects of root anatomy on sap flow rate in avocado trees; influence of rootstock on the response of avocado cv. Hass to flooding stress; methods of selection for drought tolerance in potato; and drip irrigation for the establishment of strawberry transplants in southern California.
  • Authors:
    • Ventrella, D.
    • Giorgio, D.
    • Bovera, F.
    • Lestingi, A.
    • Tateo, A.
  • Source: Journal of Food Agriculture & Environment
  • Volume: 9
  • Issue: 1
  • Year: 2011
  • Summary: A field trial was conducted to evaluate the effects of tillage system and fertilizer N applied to the preceding gramineous rotational crop on horse bean ( Vicia faba L. minor) yield and N uptake, chemical composition and nutritive value. The study took place during the periods 2002-2003 and 2004-2005 within the framework of a long-term experiment started in 1990 and involving a 2-year rotation including triticale and horse bean. The experimental layout was a split-plot design with three replicates and four tillage systems in the main plots. Tillage treatments included conventional tillage (CT), two-layer tillage (TT), surface tillage (ST) and minimum tillage (MT). In the subplots, the three N fertilization rates, applied to the preceding triticale crop, were 0 kg ha -1 (N 0), 50 kg ha -1 (N 50) and 100 kg ha -1 (N 100). Over the whole experimental period, tillage system did not significantly influence horse bean seed yield, N uptake, crude protein content and 48-h in vitro true dry matter digestibility. In spite of many significant interactions among experimental variables, there were comparable results under the different tillage systems, in both the less favourable and more productive years. N fertilization, applied to the preceding gramineous crop, did not exert noteworthy effects on horse bean seed quantiqualitative parameters studied. Continuous reduced tillage management, such as two-layer, surface and minimum tillage, would represent a viable alternative to conventional tillage for horse bean production, under rainfed Mediterranean conditions. In addition to their nutritional significance, these results are of economic and environmental importance, given the interest in adopting reduced tillage systems to limit the risk of soil erosion and degradation. The rate of fertilizer N should be optimized as a function of the production and quality of the preceding cereal crop.