Dioecism has always been an issue in many plant species with its numerous disadvantages, especially in woody trees such as date palms. As one of the most important crops in the Middle Eastern countries, researchers are having problems identifying of sex of the plant in its early stages of development. Hence, proper population stands in the male: female ratio for maintenance is almost impossible in the field for better production. In this study, sex determination of date palm (Phoenix dactilyfera L.) were identified in regions of the Y chromosome (Date-SRY) gene, the pivotal gene that initiates sex determination, using a new technique and thus an economically desirable objective, which will significantly impact profits in seed based cultivations. Partial sequences of the Date-SRY were taken and amplified by nested polymerase chain reaction (PCR). According to the results, the exact sex of date palm was identified in all the tested plants, while amplified regions of the Date-SRY gene closely matched with the human and papaya sequences. In addition, a primer pair was designed to amplify the sequences of the SRY-date gene with confidence that it will identify male date palms. These primer sequences include SRY-date Forward 5'- cggccctctaagtatctgtgcgcaacg-3' (SRY-date F) and the SRY-date Reverse 5'- gtttgcacttcgaagcagag-3' (SRY-date R). The complete sequence of the DNA has been registered and deposited in GenBank (BankIt1598036 DPSRY1 KC577225 thenKJ873056).

Plant response to salt stress and the mechanism of salt tolerance have received major focus by plant biology researchers. Biotic stresses cause extensive losses in agricultural production globally, but abiotic stress causes significant increase in the methylglyoxal (MG) level of GlyoxalaseI (Gly I). Identification of salt-tolerant genes when characterizing their phenotypes will help to identify novel genes using polymerase chain reaction (PCR) to amplify the DNA coding region for glyoxalase I. This method is specific, requiring only genomic DNA and two pairs of PCR primers, and involving two successive PCR reactions. This method was used rapidly and easily identified glyoxalase I sequences as salt-tolerant genes from Jojoba (Simmondsia chinensis (Link) Schneider). In the present study, the glyoxalase I gene was isolated, amplified by PCR using gene-specific primers and sequenced from the jojoba plant, then compared with other glyoxalase I sequences in other plants and glyoxalase I genes like in Brassica napus, ID: KT720495.1; Brassica juncea ID: Y13239.1, Arachis hypogaea; ID: DQ989209.2; and Arabidopsis thaliana L, ID: AAL84986. The structural gene of glyoxalase I, when sequenced and analyzed, revealed that the uninterrupted open reading frame (ORF) of jojoba Gly I (Jojo-Gly I) spans 775 bp, corresponding to 185 amino acid residues, and shares 45.2% amino acid sequence identity to jojoba (Jojo-Gly I). The cloned ORF, in a multicopy constitutive expression plasmid, complemented the Jojo-Gly I, confirming that the encoded Jojo-Gly I in jojoba showed some homology with other known glyoxalase I sequences of plants.

The present study aimed to identify some metabolites products obtained from different jojoba callus tissue extracts using gas chromatography/mass spectrometry analysis (GC-MS). It is known that Jojoba, a medicinal and oil-yielding, has multi-purpose uses. In addition, it produces toxins, fatty acids, phenolic compounds and other secondary metabolites from callus identified using GC-MS. Despite the direct effect of 2,4-D on directing the explant towards callus induction, it has interaction effect with Kin and achieves hormonal balance inside the explant. There is a significant interaction effect between Kin and 2,4-D. The increased concentration of both Kin and 2,4-D raises the extent of nodal segments response towards proliferation, development, and callus induction. Our results showed that the interaction effect between Kin and 2,4-D is the best results for phytochemical active constituents formation achieved from callus cultured. Qualitative results revealed that increasing cytokinins Kin concentration leads to slightly double increase in active constituents from the explants for Triodecanoic and Methoxyacetic acids. While, the gradual increase of 2,4-D to 2.0 mg l-1 caused a single increase in active constituents for Triodecanoic, Methoxyacetic and Octadecanoic acid, respectively. On the other hand, Decanoic acid has no effect by adding both hormones (Kin and 2,4-D) and also Octadecanoic acid when kin is added. Also, there is a direct relation between the development of callus and reproduction of active phytochemical constituents, which increase qualitatively by increasing callus development and 2,4-D hormone concentration at 2 mg l-1 for 1-Hexadecanol, Nonadecatriene, Aristolene and Tricosene, respectively compared to free hormone treatment. Key words: Active constituents, callus, fatty acids, jojoba, Simmondsia chinensis.

BackgroundJojoba (Simmondsia Chinensis L.) is a dioecious perennial evergreen shrub native to the south-western desert of North America and has now been introduced to Middles East. Currently, there is low production of jojoba globally, mainly due to the high male to female ratio in the plantations since they are mainly established from seed. Hence, a proper population stand in terms of the male: female ratio is almost impossible to maintain in the field, leading to reduced production. We report a breakthrough in the methodology for determining the sex of jojoba plants. Our research revealed that the jojoba genome contains the sequence of SRY gene, which encodes a protein similar to that found in the human Sex-Determining Region (SRY) gene. This region was amplified and matched with sequences found in papaya and human. ResultsThe jojoba-SRY regions (SRY gene) was amplified, and we closely matched with sequences of SRY in the papaya and human. The complete sequence of the DNA was deposited in GenBank (BankIt MK991776,3 60pb). Our newly-developed method is rapid and straightforward, representing a breakthrough for sex determination strategies of jojoba plants to identify sex at early developmental stages. ConclusionThe uniqueness of this approach is that it targets specific sequences in SRY, a region extensively studied in human genetics but also apparently recognizable in plants. This useful molecular diagnostic tool is vital in agronomical breeding programs for sex determination in long-lived jojoba crops.

Potato is one of the major food crops and considered the fourth most important food crops worldwide. The insect and fungal infections are the significant constraints for potato production in the Arab countries, causing yield losses reaching more than 20%. Polymerase chain reaction (PCR) was used to amplify a single copy of Bacillus thuringiensis Crystal Protein Cry1Ca (cry1Ca) gene from extracted DNA to screen for the presence or absence of this gene. Potato fruits slices were agroinjected with plasmid pRI201-AN-GUS DNA for transient assay of β-glucuronidase gene (GUS). The transformation was performed using the disarmed A. tumefaciens strain LBA4404 harboring a binary vector pRI201-AN-GUS- Cry1Ca. Genetically modified potato plants were selected on Kanamycin-containing Murashige and Skoog medium (MS-media) and subcultured later to MS-media supplemented with 1.0 mg L -1 6-Benzylaminopurine (BA (and 1.5 mg L -1 ∞-Naphthaleneacetic acid )NAA(. A. tumefaciens strain LBA4404 carried out the plant binary vector pRI201-AN-GUS, and pRI201-AN-GUS- Cry1Ca were used for transient expression assay. The Synthetic Cry1Ca (cry1Ca) gene, under the control of a CaMV 35S and the caste, also contained β-glucuronidase (GUS) gene. Agroinjection is an efficient transient uidA expression assay for reporter gene and analysis of candidate genes in plants. The successful transformation of Cry1Ca gene potato plants will contribute to increasing yield and food security in the future. Finally we describe her a protocol for the genetic transformation of potato based on agroinjection using A. tumefaciens carrying a plasmid (pRI201-AN-GUS- Cry1Ca) expressing a reporter uidA gene in addition to describing transient expression evidence based on histological and molecular assays.