RESUMO
Date palm (Phoenix dactylifera L.) is cultivated in arid and semiarid regions worldwide. Given the dioecious nature of this plant, gender identification is very important at the seedling stage. Molecular markers are very effective tools that help in gender identification at this stage. A sequence characterized amplified region (SCAR) marker linked to sex-specific regions in the genome of date palm was developed. Of the 300 tested randomly amplified polymorphic DNA (RAPD) primers, only one primer (OPC-06) produced reproducible band (294 bp) in male plants. The PCR product of this primer was cloned and sequenced. The specific primers were synthesized for amplification of a 186 bp fragment in male date palm plants. These primers were validated in male and female date palm plants, wherein the designed SCAR marker was reported only in male plants and no amplification was observed in female plants. The developed SCAR marker was used with seedlings of date palm and proved very effective in identification of gender.
RESUMO
Reseda pentagyna is the only endemic species among the seven species of the genera Reseda found in Saudi Arabia. Probably no information is available on regeneration by conventional method of regeneration through seeds or cuttings. Therefore, alternative method of tissue culture was attempted to regenerate and multiply the plant. High shoot regeneration (14.44 shoots/explant) was obtained after four weeks, when shoot cuttings cultured on MS containing BA at 1.0 µM. Other cytokinins e.g., Kn, 2iP and TDZ found to be less effective in bud induction and shoot multiplication. Individual shoots were rooted on MS medium supplemented with various auxins at 0.5-5.0 µM concentrations. The IBA (1.5 µM) supplemented MS media induced maximum (83.3%) rooting. The plantlets were acclimatized and hardened under greenhouse conditions in plastic pots containing soil and farm yard manure with 95.0% success. The protocol developed would help to multiply the plant as well as conserve them in natural habitat. This can also be utilized to obtain active constituents for pharmaceutics and genetic manipulations.
RESUMO
Early sex identification of Date Palm (Phoenix dactylifera L.) at seedling stage is an economically desirable objective, which will significantly increase the profits of seed based cultivation. The utilization of molecular markers at this stage for early and rapid identification of sex is important due to the lack of morphological markers. In this study, a total of two hundred Inter Simple Sequence Repeat (ISSR) primers were screened among male and female Date palm plants to identify putative sex-specific marker, out of which only two primers (IS_A02 and IS_A71) were found to be associated with sex. The primer IS_A02 produced a unique band of size 390 bp and was found clearly in all female plants, while it was absent in all male plants. Contrary to this, the primer IS_A71 produced a unique band of size 380 bp and was clearly found in all male plants, whereas it was absent in all the female plants. Subsequently, these specific fragments were excised, purified, and sequenced for the development of sequence specific markers further in future for the implementation on dioecious Date Palm for sex determination. These markers are efficient, highly reliable, and reproducible for sex identification at the early stage of seedling.
