KARYOTYPIC AND CYTOGENETIC ANALYSIS FOR JOJOBA PLANTS AND EARLY DIAGNOSIS OF SEX IN JOJOBA BY AMPLIFICATIONS OF SRY GENE AS DIRECT LINK TO SEX DETERMINATION CHROMOSOME
MOHEI EL-DIN SOLLIMAN *
Department of Plant Biotechnology, College of Agricultural and Food Sciences, King Faisal University, P.O.Box 400, Al-Ahsa 31982, Kingdom of Saudi Arabia and Department of Plant Biotechnology, National Research Centre, Dokki-Egypt, Cairo, P.O.Box. 12622, Egypt.
HEBA ALLAH ADEL MOHASSEB
Department of Plant Biotechnology, College of Agricultural and Food Sciences, King Faisal University, P.O.Box 400, Al-Ahsa 31982, Kingdom of Saudi Arabia and Department of Plant Biotechnology, National Research Centre, Dokki-Egypt, Cairo, P.O.Box. 12622, Egypt.
IBRAHIM SAKER AL-MSSALLEM
Department of Plant Biotechnology, College of Agricultural and Food Sciences, King Faisal University, P.O.Box 400, Al-Ahsa 31982, Kingdom of Saudi Arabia.
AHMED SAUD ALSAQUFI
Department of Animal Production, College of Agricultural and Food Sciences, King Faisal University, P.O.Box 400, Al-Ahsa 31982, Kingdom of Saudi Arabia
*Author to whom correspondence should be addressed.
Abstract
Dioecism, which is associated with sexual dimorphism, has always been a problem with cultivating plant species, especially in woody trees. In dioecious plants, the sex of the plant is usually difficult to identify, especially before flowering and during the very early stages of development. In jojoba plants the sex can only be identified when it blooms. Hence, a proper population standard in terms of the male: female ratio is almost impossible to maintain in the field, leading to a reduced production. Jojoba is considered as an industrial and medical plant, with chromosome number 2n =52 and the half number of chromosomes in jojoba is 1x=13. It is knowns somatic cells of jojoba are tetraploid the root tips of germinated seeds of jojoba and Karyotypes imaged by digital camera and probably represents the taxon adapted to desert areas by polyploidization in the order. In this work we describe a cytological method based on evaluating the data on the chromosome number and karyotype studies of the jojoba and relative length (RL), and centromeric index (CI) and area of chromosome are evaluated. The chromosome complement consists of six metacentric chromosomes, sub-metacentric chromosomes, acrocentric chromosomes. From the results, average length of chromosomes varies in the jojoba plant ranging from 0.61 μm to 2.84 μm. Results indicated that jojoba plant has symmetric karyotype with 6 m + 3 sm+ 4 acro. Therefore, jojoba represented the advanced karyotype by showing the maximum number of the metacentric chromosome. The amplified regions of the jojoba-SRY genes closely matched with sequences of SRY (Sex-Determining Region) in the papaya and human. We designed two sets of primers that we're able to amplify a fragment of approximately 330 pb and 470 bp, respectively, only in dioecious, male plants and human male samples. The complete sequence of the DNA was deposited in GenBank (BankIt MK991776,3 60 pb).
Keywords: Jojoba, cytological analysis, karyotype, chromosomes