Storage of nematode-infected soil, roots and nematode suspensions is important in nematological research. The available storage methods are based on potato cyst nematodes, where cysts with viable eggs can be stored for long periods at 4 degrees C. When dealing with other nematode species, understanding the effect of storage temperature is crucial. This study was designed to investigate the decline rate and survival of four root-knot and a lesion nematode of both temperate and tropical origin, when stored at 4 degrees C in three substrates: water, soil and roots. The starting density (P-i ) for each substrate was determined at t = 0 and survival of all nematode species was estimated at 10-day intervals for 100 days. During storage, population densities of all species declined in all substrates exponentially. A slower decline rate (r(d) = 0.988-0.999) was observed for juveniles of Meloidogyne fallax in water, soil and roots compared to juveniles of M. hapla and Pratylenchus penetrans. Meloidogyne incognita was seriously affected by cold storage with the highest decline rate (r(d) = 0.919-0.977) observed in all substrates. Only data on the root substrate were obtained for M. javanica with a decline rate of (r(d) = 0.977) predicting zero survival at t > 100 days. Notable is the higher fraction of surviving P. penetrans (P-i = 0.238-0.545) in all substrates during the storage period, compared with all other species. Based on the results, it is recommended to process nematode samples in the three substrates as quickly as possible, as underestimation of the actual population densities is likely. Consequences of cold storage in handling and processing of samples from different substrates are discussed.

The initial outbreak of Xylella fastidiosa subsp. pauca (Xfp) on olive groves in Salento (Apulia, Italy) dates back to the years 2008 and 2009 when extensive twig and branch diebacks were observed in the area of Gallipoli area (province of Lecce). Subsequently, the bacterium also spread northwards to other areas of Apulia. In many cases, entire olive groves, also including the centennial ones, died. After the crown collapse, in many cases, it has been observed that the suckers are resprouting at the base of the trunk. After two to three years, such suckers usually died as well. However, during the last four to five years, in the first Xfp outbreak area, a complete restoration of the crown of the Xfp-susceptible cultivars Ogliarola salentina and Cellina di Nard & ograve; has been noticed. Such trees or olive groves also started to yield again. To monitor this tree resilience phenomenon, together with local non-profit organizations, a survey in the province of Lecce has been carried out to find olive groves for which any curative or agronomical practices have been applied since the bacterium outbreak. Resilient olive groves are scattered in many municipalities all over the province of Lecce. The phenomenon regards both young and adult olive groves and also includes some centennial trees. In many cases, the trees are yielding fruits, and farmers started to cultivate them again. Olive resilience in Salento is already being studied and can represent a significant opportunity to restore the local and valuable olive germplasm.

Urban forest trees are vital components of urban ecosystems, offering a range of benefits that are essential for improving the livability and sustainability of cities, providing numerous advantages for both the environment and public health. They enhance air quality by filtering pollutants, assist in regulating urban temperatures, and alleviate the urban heat island effect, which can result in substantial energy savings. Trees are often vulnerable to pathogens and pests that can cause significant damage. A survey of different trees in five provinces of Iran revealed a severe decline and dieback disease on woody plants. The affected trees included ailanthus, cedrus, cypress, ash, haloxylon, walnut, magnolia, black mulberry, paulownia, pine, oriental plane, apricot, wild pear, and elm trees. Samples of symptomatic branches and trunks were collected, and the causal fungal pathogen was isolated on potato dextrose agar (PDA) media. A total of 90 fungal isolates were obtained from trees (60 isolates) and insects (30 isolates) and then morphological investigations were done for all isolates. Molecular identification was confirmed through sequencing of the ITS and tub2 regions. This study reports 14 new hosts for Paecilomyces formosus in Iran and worldwide. Pathogenicity tests were conducted on detached branches of apricot, ailanthus, cypress, pine, sycamore, and walnut trees. The study showed that most isolates were pathogenic to six woody plants, and some isolates were associated with disease for eight woody plant species. Additionally, potential vectors and reservoirs for P. formosus were assessed in different beetles, including Aeolesthes sarta, Scolytus kirschii, and Orthotomicus erusus in Tehran, Alborz, Qazvin, Lorestan, and Zanjan Provinces. The results confirmed the potential of beetles for the transmission and maintenance of P. formosus.

Seagrass meadows are globally recognized as critical natural carbon sinks, commonly known as 'blue carbon'. However, seagrass decline attributed to escalating human activities and climate change, significantly influences their carbon sequestration capacity. A key aspect in comprehending the impact of seagrass decline on carbon sequestration is understanding how degradation affects the stored blue carbon, primarily consisting of sediment organic carbon (SOC). While it is widely acknowledged that seagrass decline affects the input of organic carbon, little is known about its impact on SOC pool stability. To address this knowledge, we examined variations in total SOC and recalcitrant SOC (RSOC) at a depth of 15 cm in nine seagrass meadows located on the coast of Southern China. Our findings revealed that the ratio of RSOC to SOC (RSOC/SOC) ranged from 27 % to 91 % in the seagrass meadows, and the RSOC/SOC increased slightly with depth. Comparing different seagrass species, we observed that SOC and RSOC stocks were 1.94 and 3.19-fold higher under Halophila beccarii and Halophila ovalis meadows compared to Thalassia hemprichii and Enhalus acoroides meadows. Redundancy and correlation analyses indicated that SOC and RSOC content and stock, as well as the RSOC/SOC ratio, decreased with declining seagrass shoot density, biomass, and coverage. This implies that the loss of seagrass, caused by human activities and climate change, results in a reduction in carbon sequestration stability. Further, the RSOC decreased by 15 %, 29 %, and 40 % under unvegetated areas compared to adjacent Halophila spp., T. hemprichii and E. acoroides meadows, respectively. Given the anticipated acceleration of seagrass decline due to climate change and increasing coastal development, our study provides timely information for developing coastal carbon protection strategies. These strategies should focus on preserving seagrass and restoring damaged seagrass meadows, to maximize their carbon sequestration capacity.

In Saudi Arabia, tree mortality has abnormally increased over the past ten years, exceeding regulatory standards without clear interpretation. The present study aimed to investigate three attacked tree populations in different biogeographic regions of Saudi Arabia. For this purpose, climatic data from the last thirty years, forest densities, soil cover, pest search, and insect damage to trees have been reported. The results of this study show a distinct climate change manifested by an increase of 2 degrees C in temperature accompanied by a decrease in precipitation and the extension of drought periods during the last 30 years. Analysis of satellite images and the computation by quadrat methods revealed a decline in forest density and soil tree cover caused by dieback associated with an increase in the rate of tree pest attacks. Furthermore, tree investigations show attacks of the xylophagous beetles Steraspis speciosa and Paropta paradoxus on Acacia population in the north and centre of the country. In addition, many strains of termites are attacking the Dobera glabra population in the south of the Kingdom. This study shows that tree dieback, as a response to long periods of drought, when associated with pest attacks, provokes a dramatic decline in forest tree heritage. Climate change is the principal precursor to forest decline and pest invasion in Saudi Arabia.