Lemon Orchards Research Articles

Assessment of thrips species diversity and their impact on lemon orchards in the Eastern Mediterranean Region of Türkiye

Thrips are polyphagous, and some species cause serious damage to citrus fruits worldwide including Türkiye. This study was conducted to determine thrips species on different lemon varieties in the Eastern Mediterranean Region in Türkiye. Surveys were conducted on lemon orchards in 2017, 2018 and 2019. Thrips species and damage on lemon varieties in the Eastern Mediterranean Region is not fully examined therefore this study helped to understand the biodiversity and damage of thrips species on lemon orchards in this region. Eight thrips species were determined. Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) was found to be the most common species on Kütdiken, Interdonate and Mayer lemon varieties in Adana and Hatay. Thrips hawaiiensis (Morgan) (Thysanoptera: Thripidae) was detected as the most common thrips species in Mersin on Kütdiken and Interdonate. T. hawaiensis was first detected in Türkiye in 2015, and it has become the dominant species in lemon orchards in Mersin province. Moreover, the Shannon-Wiener values (H=0,99525, EH=0,478614), and the Simpson Biodiversity values (D=0,44972, Sd=0,5502) were calculated to determine thrips species diversity in the Eastern Mediterranean Region in this study. During the late flowering period, Thrips hawaiiensis had a higher population density in Kütdiken, Interdonate and Mayer varieties. This resulted severe damage to fruit. It is important to note that F. occidentalis does not cause any damage to lemon fruits. In this study, the distribution and biodiversity of thrips species based on lemon varieties were studied in Türkiye, with a focus on their distribution across provinces.

Soil Microbial Communities in Lemon Orchards Affected by Citrus Mal Secco Disease.

Mal secco is a vascular disease of citrus caused by the mitosporic fungus Plenodomus tracheiphilus. Soil containing infected plant material constitutes an inoculum source for root infections. In this study, the soil bacterial and fungal communities of five lemon orchards located in Syracuse Province (Sicily, Italy) affected by mal secco were analyzed. Soil samples were collected under lemon tree canopies and subjected to total genomic DNA extraction. The fungal DNA was detected through qPCR in all orchards, with variable concentrations. Bacterial and fungal communities were profiled using 16S and ITS amplicon-based high-throughput sequencing, respectively. According to our results, the relative abundances of the most represented bacterial phyla (e.g., Proteobacteria, Actinobacteriota, Acidobacteriota) changed across the orchards, while in the fungal community, the phylum Ascomycota was dominant, with Basidiomycota and Mortierellomycota abundances fluctuating. On the whole, β diversity analysis showed significant variation in the composition of the soil microbial communities across the orchards. This result was confirmed by the analysis of the core community (taxa present at ≥ 75% of total samples), where putative beneficial bacteria resulted in significantly enriched fungus-infected soil samples, suggesting complex microbial interactions. Our findings shed light on the composition and diversity of the soil microbiome in lemon orchards with the occurrence of mal secco infections.

Environmental Impacts Associated with the Production and Packing of Persian Lemon in Mexico through Life-Cycle Assessment

In this study, the environmental impacts associated with the intensive production of Persian lemons are assessed, including the agricultural and packing phases of the fresh fruit. A life-cycle assessment (LCA) tool was used in accordance with the ISO 14040 and 14044 standards and implemented in SimaPro PhD (9.2) software. The life-cycle inventory database was primarily composed of data collected during field visits to local lemon orchards and the main packing company in the region. The functional unit was defined as 1 kg of packed fresh Persian lemons. The selected impact categories were the carbon footprint, water footprint, and energy footprint, and the results obtained for the defined functional unit were 405.8 g CO2 eq, 40.3 L of water, and 5.9 MJ, respectively. The industrial packing phase of the fruits had a greater impact on the carbon and energy footprints, mostly due to the manufacturing of packaging materials and cardboard boxes, followed by the transportation of supplies. Regarding the water footprint, the agricultural phase was identified as the most significant contributor to water consumption, primarily attributed to maintenance operations and the application of agrochemicals.

Mating type and microsatellite genotyping indicate that the Tunisian population of Phyllosticta citricarpa is clonal and thrives only asexually

Citrus black spot (CBS) caused by Phyllosticta citricarpa was reported for the first time in Tunisia in 2019. This was also the first reported occurrence of the disease in a Mediterranean climate. In Tunisia, CBS is mainly found in lemon (Citrus limon) orchards, and is seldom observed on sweet orange (Citrus × sinensis). This recent finding in North Africa raises questions about how the disease has been able to spread under Mediterranean climatic conditions. In this work, 216 Phyllosticta strains collected from lemon orchards in 2021, 2022 and 2023 throughout the country's main citrus-growing provinces were characterised by species morphological and molecular identification, mating type and Simple Sequence Repeats (SSR) microsatellite genotyping (MLG). P. citricarpa was the only species found to be associated with CBS in Tunisia. Although P. citricarpa is a heterothallic fungal species, potentially able to reproduce both sexually and asexually, a single mating type (MAT 1-1-1) idiomorph was found in the population. In addition, three MLGs were observed, across ten microsatellite loci, one of which was massively represented (93 %), indicating a clonal population. The clonality observed suggests a single recent introduction of the pathogen into the country. These findings support the idea that in Tunisia, P. citricarpa only reproduces asexually by pycniospores, with a relatively limited dispersal potential. This is consistent with the absence of pseudothecia on the leaf litter. These results show that CBS is able to thrive under Mediterranean conditions, even in the absence of sexual reproduction. This should be taken into consideration for CBS risk assessment and management.

Spatial distribution pattern of male adults of Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) in lemon orchards in Northern Portugal

AbstractPhyllocnistis citrella Stainton, commonly known as the citrus leafminer, threatens global citrus production. This study focuses on elucidating the population dynamics and spatial distribution of P. citrella in lemon orchards located in Northern Portugal. From May to December, using delta traps with sexual pheromones, the levels of the adult population were monitored, and aggregation indices were calculated. Five distinct density peaks are observed, with the highest recorded in late July to early August. Spatial distribution consistently indicated an aggregated pattern. However, temporal variation in distribution was observed on specific dates. According to our results, it is suggested deploying two or three traps per hectare during peak density periods. This study significantly advances our understanding of P. citrella dynamics, emphasizing the need to consider spatial and temporal patterns for effective pest management. The outcomes underscore the importance of further exploration into factors influencing distribution patterns to refine control strategies. These insights are crucial for devising targeted and efficient measures to mitigate the impact of P. citrella on citrus orchards globally.

Evaluating Soil Fertility and Plant Nutrient Status of Lemon (Citrus Limon L.) Orchards in the North-Eastern Region of Bangladesh

Soil (0 to 15 cm and 15 to 30 cm depth), leaf and fruit samples were collected from seventeen orchards of lemon (Citrus limon L.) from different locations of Habiganj district to evaluate the physicochemical properties, nutrient status of soil, and nutrient concentrations in lemon leaves and fruits. The soil was found to vary pH from extreme to medium acidic (3.9 to 6.0), organic matter content 0.63 to 1.71% at 0 to 15 cm and 0.16 to 1.42% at 15 to 30 cm depth. Electrical Conductivity was found non-saline in nature which was 37.9 to 100.1 μS/cm at 0 to 15 cm and 25.1 to 69.0 μS/cm at 15 to 30 cm depth. The dominant soil textural class was sandy clay loam. The total N, P, K and S in soils were found 0.038 to 0.085%, 0.024 to 0.071%, 0.022 to 0.144%, and 0.040 to 0.294% at 0 to 15 cm depth, respectively and 0.012 to 0.076%, 0.024 to 0.056%, 0.012 to 0.139%, and 0.016 to 0.333% at 15 to 30 cm depth, respectively. Available N was found 20.37 to 67.90 mg/kg at 0 to 15 cm and 20.37 to 74.69 mg/kg at 15 to 30 cm depth. Major soil samples were found low in available phosphorous, 0.35 to 66.95 mg/kg at 0 to 15 cm and 0.83 to 29.19 mg/kg at 15 to 30 cm depth. Available sulphur was also found low in concentration, 4.62 to 68.48 mg/kg at 0 to 15 cm and 2.10 to 15.54 mg/kg at 15 to 30 cm depth. The exchangeable K+, Ca2+ and Mg2+ in soils at 0 to 15 cm depth were found 0.040 to 0.221 meq/100g, 0.002 to 0.046 meq/100g and 0.017 to 0.042 meq/100g, respectively and at 15 to 30 cm depth these were found from 0.025 to 0.097 meq/100g, 0.003 to 0.054 meq/100g, and 0.016 to 0.050 meq/100g, respectively. The concentrations of total N, P, K and S in leaf were 1.198 to 2.659%, 0.500 to 0.778%, 0.112 to 0.246% and 0.010 to 0.133%, respectively. The concentrations of total N, P, K and S in fruit were 0.760 to 1.549%, 0.250 to 0.611%, 0.107 to 0.190% and 0.005 to 0.031%, respectively. The present findings illustrated the low to medium soil fertility status under the lemon plantation in the north-eastern region of Bangladesh and growers could be recommended to plant lemons after applying soil amendments to improve the physico-chemical properties of soils in the north-eastern region of Bangladesh. J. Biodivers. Conserv. Bioresour. Manag. 2023, 9(1): 69-78

BIOLOGICAL CONTROL AND ANTAGONISTIC ACTIVITY OF NATURAL ENEMIES AGAINST, PAPILIO DEMOLEUS AT SAHATI REGION OF SINDH - PAKISTAN

The swallowtail butterfly is the widespread vigorous destructive pest of new growing green leaves of Citrus limon, the different species of predators and parasitoids on major pests were observed field and laboratory conditions during, 2022. The overall population of LBF was recorded (26.23±5.12) on C. limon leaves and the natural enemies were also observed namely; Peucetia viridans consequent to Cheiracanthium punctorium, Halyomorpha halys, Agelenopsis sp., Delta pyriforme (0.13±0.36), Geocoris punctipes (0.14±0.37), Aculepeira ceropegia (0.10±0.31), Menochilus sexmaculatus (0.12±0.34), Coccinella septempunctata (0.17±0.40), Brumus sp., (0.12±0.34), and ectoparasitiods; Tamarixia radiata (0.28±0.52), Tetrastichus sp., (0.30±0.54). The overall parasitiods population of eggs (11.44±2.00), larvae (6.98±1.22), and pupae (4.27±0.80), hence; the egg parasitoids; Telenomus sp., (0.11±0.33), and Ooencyrtus papilions (0.10±0.32), the larvae parasitoids, Distatrix papilionis (0.13±0.36), Apanteles papilions (0.09±0.30), and pupae parasitoids, Pteromalus puparum (0.10±0.32) were reported and found with differences in population occurrences. Thus; it is further recommended to keep toxic insecticides free lemon orchards and enhance the activity of natural enemies to reduce the pest population under field conditions.

Cicadomorpha community (Hemiptera: Auchenorrhyncha) in different agroecosystems in the north of Portugal

Abstract The infraorder Cicadomorpha is a diverse group comprising several species considered important pests of economic crops and species that may act as vectors of plant pathogens. In Europe, the gram‐negative bacterium Xylella fastidiosa is one of the most important and severe insect‐borne plant pathogens associated with the infraorder Cicadomorpha. Therefore, the knowledge of the abundance and diversity of native Cicadomorpha insect vectors related to the different agroecosystems is essential to design and implementing specific measures to control insect‐borne plant pathogens. In this work, in two consecutive years (2018 and 2019), five almond orchards, five vineyards, five olive orchards, and five scrublands distributed in the North of Portugal were sampled in three different periods (early summer, summer and autumn) to investigate species composition, richness, and diversity of the Cicadomorpha community. Also, in 2019, five lemon orchards were sampled. A total of 6056 individuals were collected (2322 in 2018 and 3734 in 2019), belonging to 71 species of three families. Observing several considered pests or vectors of vicious pathogens within these species was possible. The confirmed vectors of X. fastidiosa (Philaenus spumarius (Linnaeus, 1758) and Neophilaenus campestris (Fallen, 1805)) were captured in all agroecosystems and, in general, with more abundance in autumn. The highest abundance, richness, and diversity of Cicadomorpha were observed in vineyards. However, these parameters (abundance, richness and diversity) significantly differed between the agroecosystem and sampling period. Further research on how the composition of the vegetation cover shapes the Cicadomorpha community is essential to implement strategies to reduce the spread of insect‐borne pathogens if they are introduced into agroecosystems.

An Investigation on the Relationship Between Mineral Nutrition of Lemon and Rumple

This study investigated the relationship between Rumple and tree crown parts regarding direction, fruit development stages and fruit rind nutrient content. A Lemon orchard on which Rumple disorders have shown severely were chosen among Erdemli and Silifke region where the majority of grown lemon cultivar is Kütdiken. In this orchard, from healthy and contaminated trees samples were taken from the South and West half parts of crown and the North and East parts of the crown separately. Also, fruit samples were taken at four fruit development stages which were hazelnut-sized fruit, end of fruit enlargement, the beginning of maturation and fully mature fruit stages. The rind of samples fruit was analyzed, and their content of N, P, K, Ca, Mg, S, Mn, Fe, Zn, B, Cl and Na was determined. PCA was used to analyze these data. Biplot scheme of the 2nd Sampling from the part one-half of the trees which includes the South and West directions, that is, from the Healthy (G2S) and Rumple signed trees (G2B) taken were examined. The increase in K, Zn, Fe, Ca, and Mg is associated with Na, P and Cl concentration reduction. Besides this, in this period, it was observed that fruit rind has higher N, S, Mn and B content which were taken from part one, that is, the South and West sides, of healthy plants. The relationship identified here is important because Rumple’s symptoms become visible after this stage.

BIOTROP Taps Into Digital Learning Inovation to Strengthen Student’s Engagement on Merdeka Belajar Program

The COVID-19 pandemic has suddenly forced the world of education to carry out a more massive digital transformation that should meet student’s requirements and strengthen their knowledge, skills and competencies. The digital media developed should facilitate student’s self-learning and freedom to learn (Merdeka Belajar) amidst physical and social interaction limitations. Vocational high school students have special requirements compared to upper secondary school students in terms of soft skills and hard skills education. It is very interesting to provide digital educational media which fits their needs. This study aims to develop an online digital platform in responding to the demand of vocational schools that have joined the SEAMEO BIOTROP SMARTS-BE program since 2015 in applied tropical biology. Since 2015, SEAMEO BIOTROP has provided face-to-face mentoring to vocational high schools spread across 10 provinces in Indonesia. The Expert System for Identifying Pest and Disease on lemon orchard is a digital transformation in the mentoring method while demonstrating a new learning experience educational materials into a web-based digital platform and Android application. This expert system demonstrates the implementation of problem base learning (ProBL) concepts to enrich online learning materials for vocational schools in the age of digital science and education.

Quality of cold stored lemon fruit from orchards consociated to ancient olive trees

In the hilly area of Gioia Tauro (Calabria, Southern Italy), lemon orchards are grown in consociation with centuries-old olive trees. Lemons are partially shaded by olive canopies and the microclimate at the level of their canopies is suitable for plants growth and quality productions. Under these conditions, lemon trees are grown even without irrigation, providing, despite this limitation, a quality product. This study aimed to i) investigate the qualitative characterisation of two clonal selections of the lemon cultivar Femminello, F. Siracusano (S) and F. Zagara bianca (ZB), from the described intercropping, on irrigated (I) and non-irrigated (NI) crops; ii) assess the quality preservation during cold storage, in order to evaluate the availability of lemons for marketing in a period of shortage such as the summer season. Fruits were harvested at commercial maturity, and cold stored at 10±1°C and RH 85-90%, for 60 days. Decay incidence, physiological disorders, weight loss, and the main physical-chemical parameters were assessed at harvest (T0) and every 15 days (T15, T30, T45, T60). The absence of decay and physiological disorders was observed throughout the 60-day storage period, in both clonal selections under the two management conditions. The weight loss was greater in fruits from irrigated lemon groves of both S and ZB. S_I showed significantly lower fruits weight and higher titratable acidity than S_NI. Total soluble solids and titratable acidity were statistically lower for ZB_I than for NI fruits.

DEVELOPMENT AND EVALUATION OF UNMANNED GROUND VEHICLE FOR AUTOMATED ENVIRONMENTAL MONITORING OF LOW-HEIGHT TUNNEL FARMS

Agricultural machinery is an essential tool for improving agricultural production per unit area. It helps farmers to grow more crops in less time and with greater efficiency to meet food security for exponentially growing population. Tunnel farming is an agriculture technique in which the crop is grown in a long row, covered with plastic sheets to maintain favorable environment for crop growth while minimizing environmental and biological hazards. Tunnel farms are divided into low height tunnel, high tunnel, and walk-in tunnel. It is important to monitor tunnels for temperature and relative humidity because these two factors promote disease and pest attack. In low height tunnels, it becomes difficult to physically monitor temperature variations, humidity variation and pest or disease attack. Therefore, it is required to develop suitable solution to this problem which can be provided in the form of small, unmanned ground vehicle (UGV) equipped with necessary sensing devices. In this study, a small UGV having camera, temperature and humidity sensors was developed and evaluated at four different sites. These sites included lemon orchard, research farms, main boulevard and field farm. The temperature and humidity reading were recorded at 8:00, 11:00, 14:00 and 16:00 a day on 10, 20, 30, 40, and 50 ft. length from field boundary. In lemon orchard temperature is minimum (240C) and humidity is maximum (69%) at 8:00 AM. In the evening at 2:00 PM temperature was maximum (390C) and humidity was minimum (45%). In research farm temperature was minimum (280C) and humidity was maximum (65%) at 8:00AM. In the evening at 2:00PM temperature was maximum (430C) and humidity was minimum (40%). In Kfueit boulevard temperature was minimum (250C) and humidity was maximum (69%) at 8:00AM. In the evening at 2:00PM temperature was maximum (400C) and humidity was minimum (46%). In Progressive farmer farm temperature was minimum (300C) and humidity was maximum (69%) at 8:00AM. In the evening at 2:00PM temperature was maximum (430C) and humidity was minimum (46%).

Effectiveness of various insecticides and predatory bug, Orius laevigatus (Fieber, 1860) (Hemiptera: Anthocoridae) releases on Thrips hawaiiensis (Morgan, 1913) (Thysanoptera: Thripidae) in lemon, Citrus limon (L.) (Rutales: Rutaceae), orchard in Mersin (Türkiye)

The important invasive thrips species Hawaiian flower thrips, Thrips hawaiiensis (Morgan, 1913) (Thysanoptera: Thripidae) was first reported in Türkiye in 2015. Since then, it has been causing damage in lemon orchards. This study was conducted to reveal the most effective insecticides, the most effective spraying time and the efficacy of biological control. For this purpose, the effectiveness of five insecticides (480 g/l spinosad, 25% spinetoram, 100 g/l spirotetramat, 50% flonicamid, 240 g/l tau-fluvalinate), effect of three spray programs and effectiveness of predatory bug Orius laevigatus (Fieber, 1860) (Hemiptera: Anthocoridae) were tested in a lemon orchard [Citrus limon (L.) (Rutales: Rutaceae)] in Erdemli district of Mersin province in 2018 and 2019. In order to determine the most effective spraying time, three spray programs were tested. In Program 1, two sprays during the flowering period were applied. In Program 2, two sprays were applied, one at petal fall and the other at the small fruiting stage. In Program 3, one spray at petal fall and two sprays in the fruiting stages were applied. According to the results, 240 g/l tau-fluvalinate and 50% flonicamid showed the lowest efficacy of the insecticides in the three programs. Spinetoram was found the most effective of the others. Insecticide applications to control T. hawaiiensis during the flowering period (Program 1) had low efficacy. Program 3 was found to be the most effective. Predatory bug O. laevigatus, as a biological control agent was found to have a potential efficacy for suppressing T. hawaiiensis populations.

Ant community diversity in two agrosystems in Bejaia wilaya (Northern Algeria)

The present work studied the diversity of Formicidae in two agrosystems of Bejaia, a lemon orchard located at INRAA and an orange orchard located at Amizour. We used the transect method by combining three (3) sampling methods: Barber Pots or Pitfall, Bait, and manual capture. We identified 18 ant species representing 11 genera and three subfamilies: Dolichoderinae (Tapinoma magnum), Formicinae (Cataglyphis, Camponotus, Lasius, and Plagiolepis), and Myrmicinae (Messor, Aphaenogaster, Crematogaster, Pheidole, Tetramorium, and Temnothorax). The species richness was 13 species in the Oued Ghir’s site and 12 species in Amizour’s site. At INRAA, Dolichoderinae and Myrmicinae have the same proportions (43.95 and 43.17%, respectively) followed by Formicinae (12.88%). In Amizour, Formicinae showed the higher frequency (40.28%), followed by Dolichoderinae and Myrmicinae (30.47 and 29.25%, respectively). In the INRAA lemon orchard Tapinoma magnum was the dominant species with a relative abundance of 43.95%, whereas in Amizour the predominance is attributed to the Cataglyphis viatica with a relative abundance of 39.05%.

Effect of Treated Wastewater Irrigation on the Accumulation and Transfer of Heavy Metals in Lemon Trees Cultivated in Arid Environment

The Middle East is considered as one of the driest regions of the world and the use of municipal-treated wastewater (TWW) for agricultural purposes is needed. The aim of this study was to evaluate the effect of continuous irrigation of TWW in lemon orchards on the accumulation of heavy metals (HMs) in the soil, as well as their uptake and translocation to aerial parts of the trees. For this purpose, two lemon orchards were selected to be irrigated from two different water sources: TWW from a tertiary treatment plant and freshwater (SW) from Moses springs in Jordan. Continuous irrigation with TWW resulted in higher concentrations of nutrients and HM accumulation in the soil as compared to SW. However, HM accumulation in the soil was found to be within the acceptable range according to the standards of the WHO. On the contrary, the continuous irrigation with TWW resulted in the accumulation of HMs in plant parts when compared to SW irrigation; the fruits were clearly affected by the accumulation of high levels of Cd and Pb that exceed the maximum limits for the presence of HMs in plant tissues. The irrigation of lemon trees with TWW had a significant effect on the bioaccumulation factor and translocation factors (TF) of HMs into different lemon tree parts. Heavy metal accumulation coincided with high translocation rates to different tree parts, and this is considered to be a main challenge for long-term irrigation with TWW in arid environments.

Adoption and Cost-benefit Analysis of Drip Irrigation for Production of High-Value Crops in Pakistan

Drip irrigation is regarded as one of the highly efficient methods that allow limited water resources to be properly utilized. The study has been conducted to perform the economic analysis of low and high head drip irrigation systems throughout the country based on data from 100 adopters of drip irrigation through a research & development project funded by the International Center for Agricultural Research in the Dry Areas (ICARDA-Pakistan)/United States Department of Agriculture (USDA). A field survey for the study was conducted in the year 2018 in all the provinces of Pakistan. The study revealed that technology is generally adopted by the farmers having diversified income sources and medium-sized land holdings i.e. ranging from 12.5 to 25 acres. System installation cost-shared 11 percent in low-head drip system of the annual production cost of fruits. While, it shared 29, 32, and 27 percent in case of a high-head system for grapes orchards, vegetables in tunnels, and open fields, respectively. Low-head drip irrigation is profitable for dates/ lemon orchards in Khyber Pakhtunkhwa with a benefit-cost ratio (BCR) of 1.27:1.00. It results in considerable profitability for grapes orchards with BCR of 1.73:1.00 and 1.32:100 in Punjab and Balochistan provinces, respectively. The low-head system is also beneficial for mixed fruit orchards in rain-fed Punjab with a BCR of 1.24:1.00. Similarly, for high-head systems, the benefit-cost ratio was the highest for grapes produced in rain-fed Punjab (2.62:1.00), followed by squash-gourd in irrigated Sindh (2.17:1.00) bitter-gourd in rain-fed Punjab (1.50:1.00) and okra in Sindh (1.22:1.00). However, low and high-head systems could not result in considerable returns for farmers in the case of mixed fruits in Balochistan and cucumber production in tunnels in Punjab province during the study year.

Monitoring and study of bio-ecological aspects of the citrus borer, Diploschema rotundicolle (Coleoptera:Cerambycidae), in southern-Uruguay lemon orchards

The citrus borer, Diploschema rotundicolle, is a South American cerambycid beetle considered a primary citrus pest in Uruguay. Serious focalized population explosions have been registered in recent years, particularly in lemon orchards. The larvae feed on the woody tissue, causing tree deterioration and reducing grove productivity and value. Current management relies on cultural control, which is expensive and ineffective partially because of imprecise timing of interventions. Monitoring tools for adults or information of their flight periods in Uruguay are not available thus far. Working in lemon groves in southern Uruguay throughout four flight seasons (2015-2020), we used cross-vane traps coupled with white light devices to capture night-flying adults, and mesh covers around infested trees to study adult emergence. Visual observation of larval activity and oviposition damage were also performed throughout the year. Finally, Eucalyptus globulus windbreaks were checked underneath loosen barks for hidden adults. Throughout all four seasons, adult flight occurred between late January and early April, with a maximum around mid-February. Emergence from mesh-covered trees was observed in the same period. In general, oviposition damage was observed closely after the peak of adult catches. Mostly females were both trapped in light traps and emerged from infested trees. Larval activity was registered all year long. Adults were found sheltered under E. globulus barks; in this case, mostly individual males or couples were found. This study provides a monitoring tool for D. rotundicolle adult flight and information on bio-ecological aspects of this pest in southern Uruguay.

A Selective Medium for the Recovery and Enumeration of Fomitopsis meliae, Causing Lemon Canker and Brown Wood Rot

A selective medium was developed for the isolation and quantification of Fomitopsis meliae (FMS medium), the causal agent of lemon canker and brown wood rot, from plants, soil, and air. The optimal concentration and combination of fungicides and antibiotics was evaluated to determine the most selective condition for growing F. meliae. The resultant composition of the FMS medium per liter (pH 3.5) was 16 mg of thiophanate-methyl, 8 mg of dichloran, 5 mg of 2-phenylphenol, 100 mg of fluopyram, 0.5 mg of fludioxonil, 100 mg of chloramphenicol, 100 mg of streptomycin, 15 g of malt extract, 2.5 g of mycological peptone, and 15 g of agar. The fungus was successfully isolated and enumerated from air, soil, and plant tissues using FMS medium. Furthermore, FMS medium almost completely inhibited the growth of other plant-pathogenic fungi and soil and air saprophytes. This selectivity was high enough to estimate spore inoculum of F. meliae in an air sample or as a spore-trapping device in commercial lemon orchards. FMS medium will be useful for studying epidemiology and management of F. meliae.

Canker and wood rot pathogens present in young lemon orchards in south‐west Arizona

AbstractCanker and wood rots are economically important preharvest diseases of lemons in south‐western Arizona, where commercial lemon production is concentrated. However, the aetiology and epidemiology of canker and wood rots are not well understood. This study comprised a large survey of canker and wood rot incidence and severity in Arizona and the characterization of fungal species associated with the disease. A total of 5431 trees with ages ranging from 1 to 20 years old in 10 lemon orchards were surveyed from 2018 to 2020. Our survey results revealed that canker and wood rot occurred in all 10 lemon orchards studied. Canker and brown rots of twigs, branches, and trunks were the most prevalent symptoms of affected trees ranging from 1 to 20 years old. In contrast, canker and white rots of twigs and branches were observed mostly on 1‐ to 5‐year‐old trees. Disease incidence for both diseases was less than 2% on 1‐ and 2‐year‐old trees. Brown rot increased significantly in older trees, ranging from 62.9% to 100%. Fungi were isolated from canker and wood rot samples and identified based on morphological characters and DNA sequences. Fomitopsis meliae and Hypoxylon macrocarpum were the primary canker and wood rot pathogens isolated from the surveyed orchards, at frequencies of 89% and 11%, respectively. In pathogenicity tests, both fungi were capable of causing canker and wood rots on lemon cv. Lisbon branches and the necrotic length caused by F. meliae was twofold greater than that caused by H. macrocarpum.

Synchronous Worlds

In the Mediterranean basin, the archaeological presence is extremely relevant and diffuse. Together with this is a difficult intertwining with contemporary urban settlements, which archaeology, by tradition, has to be protected from. If conservation is the goal of restoration, the problem of the cohabitation between past and present use is still an issue. This paper will focus on the project of enhancement of the archaeological park of the Greek colony of Naxos, near Messina, in Sicily, led by the Department of Architecture of the University of Palermo in cooperation with the administrative head of the park. At the crossroads between the sea, the highway, a lemon orchard and the city of Giardini Naxos, the ancient Greek settlement could be an example of coexistence of the different layers composing the landscape, with the aim of making history and archaeology come to life as synchronous components of the contemporary fruition of the place.