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Amaranthus palmeri (Palmer Amaranth) is a dioecious annual weed species, originating from the Southern USA, spreading rapidly beyond its original range into Europe and the Mediterranean region. In Israel, A. palmeri distribution has expanded quickly in recent years, with farmers reporting on weed control failure using acetolactate synthase (ALS) inhibitors. Furthermore, recent studies have documented glyphosate‐resistant cases from other countries in the region, such as Spain, Greece and Turkey. We conducted a survey in order to understand A. palmeri distribution and study the occurrence of herbicide resistance to both glyphosate and trifloxysulfuron in different fields across the country. According to our data, A. palmeri population locations are aligned with the major agricultural areas for summer field crops, including the Hula Valley, Jezreel Valley and the Southern Coastal Plain. Regarding herbicide responses, while several populations showed a reduced response to glyphosate, dose–response assays did not show resistance to the recommended labelled field rate. For the ALS inhibitor trifloxysulfuron, the survival percentage was very high, especially in the southern coastline region (77%). Four populations used for dose–response studies were highly resistant, surviving at four times the recommended labelled field rate of trifloxysulfuron (30 g a.i. ha−1). Sequencing of the ALS gene, Trp574 to Leu alteration in resistant populations was recorded in all populations. The high level of resistance observed in this study, alongside the target‐site mutation found in populations of A. palmeri, endangers the future use of ALS inhibitors in corn, cotton, and other summer crops grown in Israel. [ABSTRACT FROM AUTHOR]

Invasive weeds cause significant crop yield and economic losses in agriculture. The highest indirect impact may be attributed to the role of invasive weeds as virus reservoirs within commercial growing areas. The new tobamovirus tomato brown rugose fruit virus (ToBRFV), first identified in the Middle East, overcame the Tm-22 resistance allele of cultivated tomato varieties and caused severe damage to crops. In this study, we determined the role of invasive weed species as potential hosts of ToBRFV and a mild strain of pepino mosaic virus (PepMV-IL). Of newly tested weed species, only the invasive species Solanum elaeagnifolium and S. rostratum, sap inoculated with ToBRFV, were susceptible to ToBRFV infection. S. rostratum was also susceptible to PepMV-IL infection. No phenotype was observed on ToBRFV-infected S. elaeagnifolium grown in the wild or following ToBRFV sap inoculation. S. rostratum plants inoculated with ToBRFV contained a high ToBRFV titer compared to ToBRFV-infected S. elaeagnifolium plants. Mixed infection with ToBRFV and PepMV-IL of S. rostratum plants, as well as S. nigrum plants (a known host of ToBRFV and PepMV), displayed synergism between the two viruses, manifested by increasing PepMV-IL levels. Additionally, when inoculated with either ToBRFV or PepMV-IL, disease symptoms were apparent in S. rostratum plants and the symptoms were exacerbated upon mixed infections with both viruses. In a bioassay, ToBRFV-inoculated S. elaeagnifolium, S. rostratum and S. nigrum plants infected tomato plants harboring the Tm-22 resistant allele with ToBRFV. The distribution and abundance of these Solanaceae species increase the risks of virus transmission between species. [ABSTRACT FROM AUTHOR]

Solanum rostratum Dunal is an aggressive invasive weed invading many countries worldwide. Our previous study indicated differences in herbicide response between young and mature plants. In this study, we explore the functional leaf surface anatomy of S. rostratum. Leaf area surface characterisation was performed by counting stomata, stellate and glandular trichomes on upper and lower leaf sides on scanning electron microscopy (SEM) micrographs. Total cuticular waxes were extracted and weighed in young and mature leaves. Young and mature leaves were tested for water permeability of the epidermal surfaces using the apoplastic tracer Calcofluor. S. rostratum plants were sprayed with luminous trace colour solution with and without 1% surfactant, droplet number and area were calculated. In young S. rostratum leaves, the leaf surface was densely covered with stellate trichomes on both leaf sides; however, in the mature leaf, stellate trichomes density became low, and prickle rigid increased in mature leaves. Wax amount was significantly higher in mature leaves, while number of stomata was higher in young leaves. Young leaves showed high leaf permeability, with the fluorescent dye permeating the leaf staining the vascular bundles. In young and mature leaves treated with a spraying solution with the addition of surfactant, low droplet number alongside higher coverage area was recorded. Our data highlight the notable differences in leaf epidermal structure of young versus mature plants. We conclude that differences in herbicide permeability, water loss and herbivory in young versus mature leaves of S. rostratum are governed by variation in leaf functional anatomy. [ABSTRACT FROM AUTHOR]

Global population growth is creating severe pressure on wastewater treatment plants, and specifically on sludge management. Meanwhile, the global challenge of achieving food-security requires the development of green pest control practices that maximize crop productivity. The hydrothermal technology, using subcritical water as the conversion media has been intensively studied, mostly for energy recovery purposes. Here, we focused on the aqueous phase by-product of this process and studied the subcritical water extraction of sewage sludge to recover valuable agrochemicals, with high potential of pre-emergent herbicidal activity. Full characterization of hydrothermal extracts from different reaction temperatures (200–300 °C) and times (30–120 min) highlighted the formation of pyrazine derivatives. Seed germination bioassays with three different species suggested a positive correlation between reaction temperature and extract herbicidal activity. Moreover, differences in seed viability and final root elongation between the tested crop (Trriticum aestivum) and weeds (Lapidium sativum and Amaranthus palmeri) may indicate the competitive abilities that can play a key role in weed management. Our results suggest that subcritical water can be applied as a green solvent for extracting a valuable agrochemical from sewage sludge and improving the circular economy for wastewater treatment. [Display omitted] • Sewage sludge was hydrothermally treated at elevated temperatures and holding times. • Hydrothermal aqueous products were dominated by pyrazine and its derivatives. • Positive correlation was detected between reaction severity and herbicidal activity. • Different germination behavior of 3 tested species suggests a selectivity pattern. • Results suggest a new utilization pathway for hydrothermal aqueous products. [ABSTRACT FROM AUTHOR]

Coriander, Coriandrum sativum L., is globally cultivated for various purposes, including cooking, cosmetics and traditional medicine. Coriander has been cultivated for thousands of years and desiccated coriander fruits were found in various Mediterranean archaeological sites. The existence of wild coriander that is not a cultivation escapee is questioned. This work aimed to determine whether coriander growing wild in Israel significantly differs from cultivated genotypes and might be used for future breeding purposes. Nine coriander accessions originating from wild populations were evaluated for their fruit morphology, germination rates, growth rates, and fruit volatile content in comparison to those of nine cultivated genotypes. Wild accession fruits were found to have a harder and thicker coat and a low germination rate, that was recovered by seed rescue, suggesting stronger mechanical dormancy as compared to the cultivated varieties. Wild coriander fruits had a significantly lower essential oil content but a similar volatile profile in comparison to cultivated coriander. When grown under the same irrigation conditions, wild accessions had a much smaller vegetative appearance than cultivated coriander. This study documented the existence of wild coriander accessions that are markedly different from the cultivated genotypes. We illustrate two theories for their origin: 1) they are a separate subset or outliers in the C. sativum species that may have escaped domestication. 2) they represent the ancestor of the modern coriander crop. Future genomic studies will assist in judging which hypothesis holds. [ABSTRACT FROM AUTHOR]

Carotenogenesis has been intensively studied in carrot roots, and transcriptional regulation is thought to be the major factor in carotenoid accumulation in these organs. However, little is known about the transcriptional regulation of carotenoid biosynthetic genes concerning carotenoid accumulation during infestation by the obligate parasite Phelipanche aegyptiaca. HPLC analysis revealed a decrease in carotenoid levels of the different carrot cultivars when parasitized by P. aegyptiaca. Besides, we isolated and analyzed P. aegyptiaca tubercles parasitizing the various carrot root cultivars and show that they accumulate different carotenoids compared to those in non-infested carrot roots. Expression analysis of PHYTOENE SYNTHASE (PSY1) and CAROTENOID ISOMERASE (CRTISO) as well as the strigolactone apocarotenoid biosynthetic genes DWARF27 (D27), CAROTENOID CLEAVAGE DIOXYGENASE 7 (CCD7) and CCD8 revealed that their transcript levels showed significant variation in P. aegyptiaca infested carrot roots. After parasite infestation, the expression of these genes was strongly reduced, as were the carotenoid levels and this was more pronounced in the uncommon non-orange varieties. We also analyzed the parasite genes encoding D27, CCD7 and CCD8 and show that they are expressed in tubercles. This raises important questions of whether the parasite produces its carotenoids and apocarotenoids including strigolactones and whether the latter might have a role in tubercle development. [ABSTRACT FROM AUTHOR]