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The cereal cyst nematode (Heterodera latipons) is becoming an economically important species in global cereal production as it is being identified in many new cereal cultivated areas and causes significant losses. Consequently, understanding its biology becomes crucial for researchers in identifying its vulnerabilities and implementing effective control measures. In the current study, different morphological and biochemical changes of H. latipons cysts containing eggs with infective juveniles from a barley field in Jordan were studied during the summer of 2021, at two sample dates. The first, at the harvest of the cereal crop (June 2021), when the infective second-stage juveniles (J2s) were initiating diapause, and the second, before planting the sequent cereal crop (late October 2021), when the J2s were ending diapause. The studied population was characterized morphologically and molecularly, showing 98.4% molecular similarity to both JOD from Jordan and Syrian "300" isolates of H. latipons. The obtained results and observations revealed that there were dramatic changes in all the investigated features of the cysts and eggs they contained. Morphological changes such as cyst color, sub-crystalline layer, and thickness of the rigid eggshell wall were observed. A slight change in the emergence time of J2s from cysts was observed without any difference in the number of emerged J2s. The results of biochemical changes showed that the total contents of carbohydrates, glycogen, trehalose, glycerol, and protein were higher in cysts collected in October when compared to those cysts collected in June. The SDS-PAGE pattern indicated the presence of a protein with the size of ca. 100 kDa in both sampling dates, whereas another protein (ca. 20 kDa) was present only in the cysts of October. Furthermore, the expression of trehalase (tre) gene was detected only in H. latipons collected in October. The outcomes of this study provide new helpful information that elucidates diapause in H. latipons and may be used for the implementation of new management strategies of cyst nematodes. [ABSTRACT FROM AUTHOR]

Production of common fig in Jordan has dropped more than 20-folds during the last five decades, due to several challenges, including biotic and abiotic stresses. The present study was conducted to asses a new protocol of shoot and callus development from fig apical buds. Explants of three local genotypes (Khdari, Mwazi and Zraki) were collected and grown in three culture establishment media: Murashige and Skoog (MS), Olive Medium (OM) and Woody Plant Medium (WPM). Two months later, shoot growth and callus development were measured, followed by transplanting into subculturing medium in test tubes with MS media. After additional two months, the same parameters were measured again. The results of the culture establishment showed that the highest shoot growth was obtained with OM and the highest callus development was obtained with WPM. On the other hand, the subculturing in MS medium showed prominent carryover effect of the first inoculation media, where the highest shoot growth was obtained in cultures transplanted from OM and the highest callus development was obtained in cultures transplanted from WPM. The present study delivers an improved protocol for establishment of common fig by tissue culture. [ABSTRACT FROM AUTHOR]

The availability of molecular markers in camels is limited. The aim of this study was to develop new simple sequence repeat (SSR) markers. Four breeds of pooled dromedary genome were sequenced at low coverage utilizing Roche and Illumina platforms. A total of 65,746 contigs, covering approximately 52 Mb (2316 contigs > 2 kb), were assembled. The partial genome revealed 613 SSR loci with a minimum number of 5 repeat units. Comparative chromosomal location for 60 camel loci was predicted against bovine genome assembly Baylor Btau_4.6.1/bosTau7. Ten markers (16.7%) returned matches with a >100 score and >80% identity. SSR abundance was 1 in every 84.3 kb of contigs. The SSR loci mainly comprised di- (80.8%), tri- (10.8%), tetra- (7.6%), and pentamer (0.8%) motifs. (TA)n and (AC)n were the most abundant (58.6%) dimers. Thirty SSR loci were experimentally characterized for both dromedary (16 animals) and Bactrian camels. The number of alleles ranged from 1 to 3, and the average number of fragments scored per animal ranged from 0.81 to 2. Polymorphic information content ranged from 0 to 0.66 with a mean value of 0.38. These SSR markers will be a valuable resource for further genetic studies of camels and related species. [ABSTRACT FROM AUTHOR]

Background: Cucumber (Cucumis sativus) belongs to the Cucurbitaceae family that includes more than 800 species. The cucumber genome has been recently sequenced and annotated. Transcriptomics and genome sequencing of many plant genomes are providing information on candidate genes potentially related to agronomically important traits. To accelerate functional characterization of these genes in cucumber we have generated an EMS mutant population that can be used as a TILLinG platform for reverse genetics. Principal Findings: A population of 3,331 M2 mutant seed families was generated using two EMS concentrations (0.5% and 0.75%). Genomic DNA was extracted from M2 families and eight-fold pooled for mutation detection by ENDO1 nuclease. To assess the quality of the mutant collection, we screened for induced mutations in five genes and identified 26 mutations. The average mutation rate was calculated as 1/1147 Kb giving rise to approximately 320 mutations per genome. We focused our characterization on three missense mutations, G33C, S238F and S249F identified in the CsACS2 sex determination gene. Protein modeling and crystallography studies predicted that mutation at G33 may affect the protein function, whereas mutations at S238 and S249 may not impair the protein function. As predicted, detailed phenotypic evaluation showed that the S238F and the S249F mutant lines had no sexual phenotype. In contrast, plants homozygous for the G33C mutation showed a complete sexual transition from monoecy to andromonoecy. This result demonstrates that TILLinG is a valuable tool for functional validation of gene function in crops recalcitrant to transgenic transformation. Conclusions: We have developed a cucumber mutant population that can be used as an efficient reverse genetics tool. The cucumber TILLinG collection as well as the previously described melon TILLinG collection will prove to be a valuable resource for both fundamental research and the identification of agronomically-important genes for crop improvement in cucurbits in general. [ABSTRACT FROM AUTHOR]

Plants respond to environmental stresses by altering transcription of genes involved in the response. The chromatin modifier ATX1 regulates expression of a large number of genes; consequently, factors that affect ATX1 activity would also influence expression from ATX1-regulated genes. Here, we demonstrate that dehydration is such a factor implicating ATX1 in the plant's response to drought. In addition, we report that a hitherto unknown Arabidopsis gene, At3g10550, encodes a phosphoinositide 3'-phosphatase related to the animal myotubularins (AtMTM1). Myotubularin activities in plants have not been described and herein, we identify an overlapping set of genes co-regulated by ATX1 and AtMTM under drought conditions. We propose that these shared genes represent the ultimate targets of partially overlapping branches of the pathways of the nuclear ATX1 and the cytoplasmic AtMTM1. Our analyses offer first genome-wide insights into the relationship of an epigenetic factor and a lipid phosphatase from the other end of a shared drought responding pathway in Arabidopsis.