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The recent introduction of new pest species in Morocco and other Mediterranean countries has caused serious problems for many crops. Among the newly introduced pests in Morocco, we have found the scale insects Dactylopius opuntiae (Cockerell) (Hemiptera: Dactylopiidae), Phenacoccus solenopsis (Tinsley), and Phenacoccus peruvianus (Granara de Willink & Szumik) (Hemiptera: Pseudococcidae). To control these scale pests, the parasitism potential of four parasitoid species: Aprostocetus mymaridis (Eulophidae: Hymenoptera), Anagyrus aligarhensis, Anagyrus sp., and Leptomastix epona (Encyrtidae: Hymenoptera) were investigated under laboratory (at 26 ± 2 °C, 60 ± 10% RH) and field conditions. Under laboratory conditions, the experiments were conducted in no choice feeding tests (only third nymphal instars or pre-ovipositing adult females of each scale pest were offered at a time) and choice feeding tests (third nymphal instars and pre-ovipositing adult females were offered simultaneously). We observed that none of the parasitoids tested parasitized D. opuntiae. In both laboratory experimental tests (no choice and free choice tests), A. mymaridis parasitized the highest mean number of third instar nymph and adult female of P. solenopsis (16.90–25.10, and 27.70–29.60, respectively), and L. epona found parasitized the highest mean number of P. peruvianus third instar nymph and adult female (17.70–19.90, and 20.10–24.10, respectively). Aprostocetus mymaridis was found practically suitable for the biological control program of P. solenopsis as they showed a higher level of parasitization under laboratory under field conditions (63.34%). Leptomastix epona seems to be the most successful parasitoid against P. peruvianus under field conditions (67.00%) compared to the other parasitoids tested. [ABSTRACT FROM AUTHOR]

Background: Waste disposal is an activity that pollutes the environment. The European Union has developed different legislative measures which are based on the circular economy (CE) to avoid this negative externality. The management of agricultural packaging (fertilizers and phytosanitary products) is carried out through Collective Deposit, Return, and Refund Systems (CDRRS). New regulations on waste tax the consumption of non-recyclable plastic in packaging, but also reward the use of plastic by-products from packaging. The administrations recommend using biodegradable plastic in the means of production, as well as establishing a traceability system (TS) to control the proper management of all the generated waste. The proposed measures can affect producer cost accounts. This work aimed to identify and evaluate the existing agricultural packaging management system in Spain. It also studied the influence of the price of a barrel of oil, crop surface, irrigation regime, and the type of subsectors on CDRRS, and quantified the impact of the latest fiscal measures and initiatives proposed by Spanish administrations. Results: The generation of agricultural packaging is influenced by variables including the cultivated area, irrigation regime, and agricultural subsector. The price of a barrel of oil directly influences the current by-product utilization system. Using biodegradable plastic or implementing a TS can increase production costs by up to 9.80%. The current system of subsidies to producers can soften the economic impact caused by the additional cost of biodegradable plastic (4.03%), but no subsidies have been foreseen to encourage the use of environmentally friendly alternatives. Conclusions: Findings indicate that public administrations should be guided by the specific characteristics of the different agricultural systems when defining regulations on agricultural waste management. The fixed rate in the current system of subsidies for using plastic by-products obtained from packaging should be substituted for a variable rate. Transferring powers to autonomous communities to define by-products may lead to heterogeneity in the Spanish territory. New measures derived from the recent environmental agreements to comply with the 2030 Agenda will increase production costs even after considering the current aid scheme. The subsidy coefficient should be increased to 80% of the purchase invoice. [ABSTRACT FROM AUTHOR]

The developmental time, adult longevity, survival, and fecundity of Ascogaster quadridentata reared on Cydia pomonella were studied at 25 ± 2 ºC and natural lighting. Longevity was measured in different conditions: water; water and honey; and water, honey and host. Developmental time from egg to adult was 43.67 ± 0.75 days. Honey had a significant effect on the longevity of female adults. The longevity of females with water was 3 days, whereas females fed with honey had longevity values greater than 6 days. The survival curves of adults fed with honey and adults starved were different. All males with water died before 5 days; while in honey-fed males, the last adult died on days 16 and 22, with and without a host, respectively. The female began ovipositing eggs during the first days following emergence. A female produced on average, 22.3 ± 4.7 eggs/day, and more than 10% of host eggs were superparasitized. The parasitism rate was on average 17.53 ± 2.88 hosts/day, whereas the total mean parasitism was 202.75 ± 59.24 hosts/female. This study addressed new basic biological information about A. quadridentata and contribute to a better understanding of its potential as a biological control agent of codling moth. [ABSTRACT FROM AUTHOR]

In the face of the global decline in pollinator populations, studies that serve as a basis for the conservation and management of crop pollinators are crucial. The eggplant (Solanum melongena) is a widely cultivated autogamous crop, whose production is favoured by pollination by vibrating (buzz pollinating bees). To our knowledge, thus far, no studies have tested for the pollination efficiency of non-vibrating bees, nor have any been conducted in semi-arid regions, or evaluated the influence of pollination on the chemical characteristics of the fruits. Here, we evaluated the influence of pollination by vibrating and non-vibrating pollinators on eggplant fruit set and fruit traits in two plantations within the semi-arid region of NE Brazil. We conducted 120 h of focal observations and compared the fruit set and size (weight, length, and basal and apical diameters) under different pollination treatments (open pollination, spontaneous self-pollination, hand-cross pollination and single visits by different species of pollinating bees). Nine visiting bee species were recorded, which differed in visiting frequency and behaviour, as well as in pollination efficiency. Although being autogamous, plants visited by the vibrating bee Xylocopa sp. set more fruits than open, spontaneous self- and cross-pollination. However, the fruits produced by Xylocopa sp. were lighter and smaller than those obtained through open pollination, highlighting the importance of multiple pollinator visits or pollinator diversity. Non-vibrating pollinators contributed to fruit production quantity and quality. Fruits resulting from open, hand cross-pollination and both vibrating (Euglossa sp. 1) and non-vibrating bees (Paratrigona sp.) were larger than those resulting from spontaneous self-pollination. Pollination treatments had no influence on fruit chemical properties. Our results highlight the importance of pollination to eggplant production and the benefits of both vibrating and non-vibrating pollinators. [ABSTRACT FROM AUTHOR]

Marigolds (Tagetes erecta L.) suppress nematodes and are attractive companion plants, but their role in biological control is unknown. We evaluated how exposure to marigold blooms impacts the aphid parasitoid, Aphidius platensis Brethes. Female wasps previously exposed to marigold spent more time walking and parasitizing Myzus percisae Sulzer or Schizaphis graminum Rodani aphids, and subsequently had higher parasitism rates. Meanwhile, completely starved wasps spent more time stationary and marginally more time grooming. Time spent probing, emergence rate, and sex ratio were not affected. Wasp survival was best on honey, followed by marigold, and lowest on non-blooming marigolds. Nutrient reserves of wasps given honey, aphid-infested marigold, or marigold alone were compared to newly-emerged unfed wasps. Their resulting lipid, glycogen and sugar levels were similar, suggesting that these foods helped wasps maintain reserves similar to emergence levels. These results suggest that marigold may improve biological control of aphids by A. platensis. [ABSTRACT FROM AUTHOR]

An irrigation performance analysis has been carried out in a horticultural greenhouse area located in the 'Campo de Níjar' (Southern Spain) in order to assess its irrigation productivity. Irrigation water productivity indicators were calculated for a wide sample of crops over the course of two different study periods. These productivity indices were similar in average to those reported in other nearby greenhouse irrigation districts although their variability was very high. The overall productivity ratio ( CYR) was 73.9 %. The low values for CYR were expected as irrigation water in this area has high salinity levels and low irrigation leaching fractions were applied. The influence of type of crop, greenhouse technology and agricultural season in the CYR values was analyzed. None of these factors had a statistically significant influence. A multivariate regression analysis was performed to model the crop yield as a function of several quantitative variables. The results showed that the most significant variable was the relative irrigation supply ( RIS). Other variables that had an influence of the productivity were the length of the growing cycle in the case of tomato and the number of greenhouses per farm in the case of watermelon. Results of this work are useful as they highlight the weaknesses of the system and suggest possible measures in order to improve its productivity and sustainability. [ABSTRACT FROM AUTHOR]

The work attempts to assess the effects of global warming on the efficacy of current greenhouse cooling methods following a methodology previously proved for other agricultural buildings. The cooling potential of four greenhouse cooling techniques (natural ventilation, forced ventilation, fogging and shading) were simulated by computer modelling for five European locations, calculating the greenhouse internal air temperature from measured external climate data. Four 2080s scenarios were analysed in these five locations. They were constructed as a combination of General Circulation Models (Had CM3 and ECHAM4) downscaled for Europe with the HIRHAM and RCA3 regional models and driven by the A2 and B2 socio-economic scenarios. The crop considered as reference was tomato. The results showed that, in locations in southern Europe, adding evaporative cooling methods to ventilation and/or shading will be indispensable. In some areas of northern Europe, natural ventilation will no longer be sufficient, and shading or fogging will also be necessary. The economic consequences will be important, over all in the southern locations where water consumption, investment and working costs will be higher and necessary to ensure the crop production. [ABSTRACT FROM AUTHOR]

Compost teas (CT) are fermented watery extracts of composted materials that are used to control plant diseases and on crop fertilization. In this work, aerated (ACT) and non-aerated compost teas (NCT) were obtained from four different composts: spent mushroom substrate compost, grape marc compost, greenhouse horticultural crop residues compost, and vermicompost. Physico-chemical and microbiological analysis were carried out to determine their properties. In vitro assays were performed to assess their suppressive effect on the mycelial growth of eight fungal phytopathogens. In vivo trials aimed to assess their effect on gummy stem blight ( Didymella bryonae) and powdery mildew ( Podosphaera fusca) in melon plants. Results showed that ACT and NCT filtrates inhibited the in vitro growth of all tested pathogens while autoclaved CT did not completely lose their inhibitory effect, and CT sterilized by microfiltration had no effect on the pathogen growth. The severity of powdery mildew was highly reduced by ACT and NCT from all sources, though in gummy stem blight assay only a delay in disease development was observed. In general, all compost teas showed a high level of microbial populations and nutrients. Results suggest that the efficacy of ACT and NCT firstly depend on the microbiota present in them. We consider compost teas from the four tested sources as a viable way to manage plant diseases and crop fertilization, throughout its integration in pest management programs and fertirrigation systems under different dilution rates. [ABSTRACT FROM AUTHOR]

Phenacoccus peruvianus Granara de Willink (Hemiptera: Pseudococcidae) is a new invasive mealybug that causes important damages in ornamental plants in urban landscapes and nurseries in Southern Europe. Recently, a new species of genus Acerophagus Smith (Hymenoptera: Encyrtidae) has been recorded as the main parasitoid of P. peruvianus in Spain, displacing the native parasitoid Leptomastix epona Walker (Hymenoptera: Encyrtidae). In this work, we have determined some traits of the reproductive and feeding strategies of Acerophagus sp.: fecundity, immature developmental time, host instar suitability, and preference when parasitizing P. peruvianus, and the effect of natural occurring sugar sources on adult longevity. Acerophagus sp. egg load reached its maximum when it was 5 days old. Second and third nymphal instars and adults were suitable for parasitism and immature development (efficient encapsulation was low). Immature development lasted between 20 and 22 days. Acerophagus sp. developed as a solitary parasitoid in the second instar and as a gregarious parasitoid in older instars (2-4 parasitoids per host). All the emerged offspring were females. Acerophagus sp. always preferred older instars when different host instars were available. Finally, adults lived more than 20 days when fed on honey, but they lived fewer than 3 days when fed on naturally occurring sugar sources (host honeydew and host plant flowers, Bougainvillea glabra). The consequences of these characteristics on biological control and parasitoid rearing are discussed. [ABSTRACT FROM AUTHOR]

Tomato chlorosis virus (ToCV, genus Crinivirus, family Closteroviridae) causes yellowing of tomatoes in many countries worldwide. Symptoms of ToCV infections in tomatoes include inter-veinal yellow chlorotic areas that develop first on lower leaves and then advance towards the upper part of the plant. ToCV is transmitted in nature by the whiteflies Bemisia tabaci, Trialeurodes vaporariorum, and Trialeurodes abutilonea in a semi-persistent manner. In the summer of 2006, a few potato ( Solanum tuberosum) volunteer plants heavily infested with the whitefly B. tabaci were found growing within a pepper crop in the province of Málaga, southern Spain. Leaf samples from volunteer plants were tested for the presence of ToCV by molecular hybridization and RT-PCR, and were shown to be infected. Furthermore, potato plants were readily infected by ToCV after experimental transmission using B. tabaci biotype Q as vector. ToCV was also detected in the tubers from infected plants that subsequently produced infected plants. Potato also served as virus source for tomato infection via B. tabaci transmission. [ABSTRACT FROM AUTHOR]

The standard FAO methodology for the determination of crop water requirements uses the product of reference evapotranspiration (ETo) and crop coefficient values. This methodology can be also applied to soil-grown plastic greenhouse crops, which occupy extended areas in the Mediterranean basin, but there are few data assessing methodologies for estimating ETo in plastic greenhouses. Free-drainage lysimeters were used between 1993 and 2004 to measure ETo inside a plastic greenhouse with a perennial grass in Almería, south-eastern Spain. Mean daily measured greenhouse ETo ranged from values slightly less than 1 mm day−1 during winter to values of approximately 4 mm day−1 during summer in July. When the greenhouse surface was whitened from March to September (a common practice to control temperature), measured ETo was reduced by an average of 21.4%. Different methodologies to calculate ETo were checked against the measurements in the greenhouse without and with whitening. The methods that performed best in terms of accuracy and statistics were: FAO56 Penman–Monteith with a fixed aerodynamic resistance of 150 s m−1, FAO24 Pan Evaporation with a constant Kp of 0.79, a locally-calibrated radiation method and Hargreaves. Given the data requirements of the different methods, the Hargreaves and the radiation methods are recommended for the calculation of greenhouse ETo because of their simplicity. [ABSTRACT FROM AUTHOR]

The monoculture of melon in Guatemala has caused the massive appearance of plants with an analogous syndrome for the well-known disease commonly called melon collapse, or vine decline, causing significant losses in crops. Methyl bromide is commonly used to sterilize soil prior to planting in Guatemala, but it must be phased out by 2015. The objective of this study was to evaluate the technique of grafting melon onto hybrids of Cucurbita ( Cucurbita maxima × Cucurbita moschata), as an alternative to using soil disinfectants (such as Metam sodium, 1,3-dichloropropene, and methyl bromide) for the control of collapse. The results suggested that both soil disinfection and grafting were not necessary in these locations, since there were no statistical differences in terms of yields between the treatments and the untreated control. Furthermore, these results demonstrate that decisions to disinfect the soil must be based on the firm identification of the causal agents, in addition to preliminary assessments of yield losses. [ABSTRACT FROM AUTHOR]

Abstract  Compost suppression of soil-borne diseases in horticultural crops has been attributed to the activities of antagonistic microorganisms. A great diversity of microorganisms, capable of suppressing pathogens naturally colonize compost. A large number of microbes appeared in microbiological analyses of grape marc compost. Most microorganisms were bacteria. Average percentages were 31% mesophilic and 28% thermophylic bacteria, 16% mesophilic actinomycetes and 20% thermophylic actinomycetes. Only a few mould and yeast morphologies were obtained, 4% and 1% respectively. Antagonist in vitro assays were performed with 432 microbial morphologies isolated from grape marc compost. The microbes isolated were extremely effective antagonists in in vitro assays against all the fungal pathogens tested. Seven microorganisms were selected for further bioassay with Rhizoctonia solani in radish, Fusarium oxysporum f. sp. radicis-cucumerinum in melon, and Phytophthora parasitica in tomato and two microorganisms with Pythium aphanidermatum in cucumber. Those experiments indicate that grape marc compost reduces the severity of Pythium damping-off in cucumber, but does not reduce the severity of Phytophthora root rot in tomato, Fusarium oxysporum f. sp. radicis-cucumerinum in melon and Rhizoctonia solani in radish. Better suppressive effects were not demonstrated by either compost or vermiculite amended with microbes selected from grape marc compost. [ABSTRACT FROM AUTHOR]

The results of the monitoring of Thysanoptera species on cultivated plants in Slovenia (2000–2001), Croatia (1994–1996), and Serbia and Montenegro (1988–2003) are presented in this study. The aim of the investigation was to study the host plant distribution of the predator Aeolothrips intermedius Bagnall and its potential prey. Banded thrips were found on 30 different host plant species belonging to 16 botanical families, always in mixed populations with phytophagous or facultative phytophagous insects (including 18 Thysanoptera species). On the vegetative parts of the cultivated plants, banded thrips were found less numerous in spite of the massive population of some harmful thrips species. This indicates highly important role of pollen as alternative food for Aeolothrips intermedius. [ABSTRACT FROM AUTHOR]

The relative importance of sclerotia and mycelia of Botrytis cinerea Pers ex Fr. as structures of survival in southeastern Spanish greenhouses was investigated. Sclerotia were not found in the SE region, neither on plant debris nor on living plant material, suggesting it may serve only a minor role in epidemic development. B. cinerea survived mostly as mycelium. The percentage of artificially inoculated tomato stem pieces from which mycelium was recovered, was used to quantify its survival rate. Outside the greenhouses, mycelium survived in 33% and 5% of the tomato stem pieces 110 days after inoculation in 1995 and 1997, respectively. After the same number of days inside the greenhouses, no mycelium was recovered from stem pieces in 1995, and in 1997 only 7% of the stem pieces contained mycelium. Survival of mycelium outside and inside the greenhouses was significantly ( P < 0.05) different after 47, 83, and 110 days of exposure to field conditions in 1995, but they were not different in 1997. Under controlled conditions, mycelium of B. cinerea lost viability at 100% relative humidity at temperatures ranging from 5 to 40°C, suggesting that air temperature and relative humidity accounted for loss of viability of mycelium. [ABSTRACT FROM AUTHOR]

The south of the green belt of Buenos Aires is one of the most important producers of fresh vegetables in the province. Only few of the horticultural farmers receive professional agronomic advice. For this reason, an excess of supplies are being used, irrigation water quality is unknown and soils are not analyzed. The aim of this work was to evaluate chemical and physico-chemical characteristics of soils from Florencio Varela, Buenos Aires Argentina, which have not been cultivated for over 20 years (NC), under open-Fields Cultivation systems (FC) and under Greenhouses Cultivation systems (GC). The variables analyzed were: pH in water (pH), Electrical Conductivity (EC), Total Nitrogen (TN), Extractable Phosphorus (EP), Total Oxidizable Carbon (TOC), Oxidizable Carbon associated to Mineral fraction (MOC) and Particulate Oxidizable Carbon (POC). The results showed excess of EP, high pH and loss of oxidizable carbon for FC and GC with respect to NC. Furthermore, an incipient salinity was found in GC. Under FC, EC and TN were lower than GC, probably associated with leaching due to rain. Overfertilization is common in horticultural farming in the green belt, where the worst-case scenario is represented by phosphorus due to its low mobility and high residuality. The problems detected show the need for chemical analysis on soils and irrigation water. This will avoid imbalances due to overfertilization and the use of unsuitable water, thereby preventing soil degradation and aquifer contamination. [ABSTRACT FROM AUTHOR]