Effects of different fertilization levels on Iberis semperflorens pot culture

The genus Iberis (family Brassicaceae) includes 30 species of annual and perennial herbs and subshrubs that grow in a wide area from western and central Europe to the Mediterranean Basin. IberissemperflorensL. is a perennial evergreen subshrub (30-60 cm high) endemic to southern Italy and Sicily. Due to its abundance of white flowers and extensive flowering period occurring during the winter months, the species has good potential for pot cultivation and outdoor ornamental use in Mediterranean-type climates. Reliable and efficient propagation methods for I. semperflorens nursery production have been determined. However, there are limited information on cultural techniques of this winter flowering species. The aim of this research was to compile fertilizer pot culture recommendations for this unexploited Mediterranean species. Plug plants bearing 10-12 leaves were transplanted into plastic pots (16 cm in diameter ) containing a 3 peat:1 perlite growing medium fertilized with various levels of Osmocote 16 N – 8 P – 10 K. (0.75, 1.5, 3.5 g l-1 ). Plant height, number of leaves per plant and number of inflorescences per plant were monitored during the growing cycle. Our results suggest a good adaptation of I. semperflorens to pot cultivation and significant relation between fertilization levels and flowering response

Risposta vegeto-produttiva di Nerium oleander L. alla concimazione con formulati a lenta cessione e a cessione controllata

L'utilizzo dei concimi a lento effetto è ormai molto diffuso in agricoltura. Il vantaggio di questi formulati, rispetto a quelli tradizionali, è dato dalla loro capacità di alimentare continuamente la pianta, grazie alla particolare struttura dei granuli, e di limitare le perdite di azoto nel substrato di coltura. La solubilizzazione dei concimi a lento rilascio o la liberazione dei principi attivi dei formulati a cessione controllata sono strettamente correlate all'attività microbica ed alle temperature del mezzo di coltura, per cui le piante possono reperire dal substrato quantitativi diversi in funzione delle condizioni ambientali. La ricerca è stata condotta al fine di valutare la risposta di Nerium oleander L., largamente diffuso in ambiente mediterraneo e molto apprezzato come specie da parchi e giardini, alla concimazione con Ornamental (18:6:12; 18 S; 1 Fe) e Osmocote (18:9:10; 2 MgO), concimi rispettivamente a lento effetto e a cessione controllata, somministrati in copertura o incorporati nel substrato in fase di pre-impianto. Lo schema sperimentale adottato è stato la parcella suddivisa. L'impianto è stato realizzato nel febbraio 2006, le piante sono state collocate in vasi del diametro di 18 cm con capacità di 4 l. Il substrato è stato preparato miscelando torba bionda (33%) e bruna (33%) con agriperlite (34%). Ad ogni pianta sono stati somministrati 2,5 kg di concime ogni m3 di substrato (3,75 g pianta-1), indipendentemente dal formulato e dalla modalità di apporto. L’approvvigionamento idrico è stato garantito tramite un impianto di erogazione a microportata con ali gocciolanti dotate di fori posti a 20 cm l’uno dall’altro (uno per pianta). Nel mese di settembre le piante sono state potate in modo da lasciare 3 gemme pianta-1. L'oleandro ha risposto bene all'impiego di entrambi i formulati e le modalità di somministrazione. Le piante hanno fatto osservare un ritmo di accrescimento analogo per tutte le tesi messe a confronto. Il numero di ramificazioni differenziate da ogni pianta non è stato influenzato dai trattamenti nel periodo primaverile-estivo, successivamente, a seguito della potatura a 3 gemme, si sono registrate lievi differenze a favore delle piante in cui il fertilizzante veniva incorporato al substrato. Più significative sono risultate le differenze relative all’interazione dei fattori esaminati, a favore della tesi che prevedeva l’uso del fertilizzante a cessione controllata, incorporato prima dell’impianto. La fioritura è cominciata contemporaneamente in tutte le piante. Le infiorescenze hanno differenziato un maggior numero di fiori nel mese di luglio mentre ad agosto, probabilmente a causa delle alte temperature, la produzione si è ridotta; anche in questo caso non sono state registrate delle differenze statisticamente significative sugli effetti semplici dovuti ai diversi trattamenti. La ricerca ha messo in evidenza la possibilità di adottare, per questa specie, concimi a lento effetto apportandoli in fase di preparazione del substrato o anche successivamente in copertura. La fertilizzazione con questi formulati si è dimostrata capace di provvedere correttamente alla nutrizione minerale delle piante, consentendo al contempo notevoli risparmi di manodopera e per gli impianti di preparazione e distribuzione delle soluzioni nutritive

Effetti delle epoche e modalità di concimazione su produzione e qualità del finocchio. Effects of time and method of fertilizer application on yield and quality of fennel.

Two field trials were carried out in Sicily during fall-winter and spring season to determine the influence of 9 fertilization treatments, obtained by changing the time (pre-plant and/or post-plant fertilization), and method (broadcast fertilization and/or fertigation) of fertilizer application and the type of fertilizer (mineral, organic, slow release fertilizers) on yield and quality of fennel. An unfertilized treatment (control) was also included. In all fertilized treatments, macronutrients were applied at the following total rates (kg ha-1): N (350), P2O5 (100), K2O (208). In both trials the highest yield and mean bulb weight was obtained by pre-planting application of all mineral fertilizers (51,5 and 78,4 t ha-1 in fall-winter and spring growing cycle, respectively). The lowest nitrate content have been recorded in pre-plant fertilized fennels and in those fertilized with a slow release fertilizer, while the highest value has been observed in fertigated fennels

Influence of greenhouse volume/area ratio on soil solarization efficiency.

Soil temperature under plastic cover is function of incoming radiation and thermal characteristics of the mulching material and the soil, but it could be also affected by greenhouse characteristics (structure, cover, Volume/Area ratio). The aim of this research was to evaluate the effects of different greenhouse unitary volumes and different plastic mulching on soil temperature and soil solarization efficiency. The experiment was carried out in nonheated greenhouses covered with low density transparent polyethilene (PE), located at the experimental field of AAT Department of Palermo University, Italy (138° 7' N, 13° 22' E). Four Volume/Area (V/A) ratios were tested: 1.5 - 2.0 - 2.5 - 3.0. Individual plots were covered with transparent or black PE film from the end of July till the end of August (30 days) in 2003, 2004 and 2005. Results showed a good efficiency of soil solarizzation under closed greenhouses and confirmed other studies. Maximum soil temperatures were increased solarizing under greenhouse with V/A 2.5 ratio. Plots mulched with transparent PE film reached higher soil temperatures than those mulched with black PE. Nevertheless black PE mulching under high V/A ratio greenhouses allowed to keep soil temperature over threshold values lethal for soilborne pathogens and seeds. Black PE film could be used and left on the soil even after solarization as crop mulching, saving money for mulching replacement and reducing plastic waste

Control of powdery mildew in cut roses using natural products in the greenhouse.

Roses grown under greenhouse cultivation are commonly affected by diseases and regular fungicide applications are commonly used. The aim of this research was to identify natural products that can substitute and reduce the health and environmental impacts of typical chemical treatments in the control of powdery mildew [(Podosphaera pannosa (Wallr. Fr.) de Bary] and grey mould (Botrytis cinerea Pers.). Treatments were applied in the greenhouse on the cut rose cultivars Sunluck (Gold Strike®) and Nirpbredy (New Fashion®) growing in a soilless system. Oregano and clove essential oil at 0.5 ml/l (an emulsifier was added) and sodium bicarbonate (NaHCO3) at 4 g/l were sprayed on rose plants to runoff. The controls were untreated roses and a standard chemical control (the fungicides Dinocap, Triadimenol, Dimethomorph+Sulphur, Bupirimate, Dithianon, Iprodione and Thiram) was applied in rotation. Sprays were applied every 7-10 days after the first symptoms of disease appeared. Disease incidence was checked on 100 leaflets and symptoms were evaluated using a scale from 0 (no disease) to 7 (76-100% infection). At three different times (June and November 2005 and January 2006) biometric data (stem height, stem diameter, stem flexibility, flower diameter, number of petals/flower and thorniness) and colorimetric analysis of the leaves were evaluated in order to determine the effect of treatments on cut rose quality. Treatment with essential oils and NaHCO3 was able to control the incidence and the severity of powdery mildew on roses. Ambient infection of grey mould was low and comparisons between treatments were not possible. Significant differences among the chemical and natural product treatments were found for all traits examined. Although NaHCO3 treatment controlled powdery mildew to a greater extent than essential oils, it resulted in slight phytotoxicity. These results indicate the potential use of natural products to control powdery mildew of roses and could be a good alternative to chemical fungicides. However, differences in response to powdery mildew depend on the cultivar susceptibility, period of treatments and level of control needed

Evaluation of quality parameters of strawberry fruits in modified atmosphere packaging during storage

The objective of the present study is to evaluate the effect of modified atmosphere packaging (MAP) during storage on some quality parameters of strawberries. Strawberries (cv. Camarosa) were harvested when mature, forced air cooled and divided into two groups as fruits in MAP and control. After packaging, fruits were stored at 0°C, 90 - 95% RH for 10 days plus 1 day at 20°C and 50 - 55% RH for the evaluation of shelf life. Changes in fruit quality, mass loss, decay, color, firmness, total soluble solids (TSS), acidity, glucose, fructose, saccharose and color were investigated. The mass loss and decay were lower in MAP than observed in the control whereas firmness, TSS, acidity and color did not change during storage and shelf life. The results suggested that MAP can be beneficial for reducing mass loss and decay after 10 days storage plus one day shelf life under these conditions in Camarosa strawberry variety