Species in the genus Phoenix are dioecious, requiring 5–10 yr for sex determination of individuals raised from seeds. Date palm (Phoenix dactylifera L.), an important member of the genus, is grown for food in Middle East, whereas Khejur palm [Phoenix sylvestris (L.) Roxb.] is widely used as a source of sugar in India and also as an ornamental plant in China. Availability of an accurate method for sex determination of male and female individuals at the nursery stage is highly desirable. We designed polymerase chain reaction (PCR) primers flanking simple sequence repeats (SSRs) found on the whole‐genome shotgun sequences of Phoenix. Also, three previously reported sex‐linked markers were included. Markers mPdIRDP52 and DPM4 proved to be sex linked, as they were 100% accurate and efficient for sex determination. Marker DPM4, unlike the previous markers, showed distinct bands for both “X” and “Y” alleles and proved to be very efficient in sex determination. Validation of the marker using F1 population (192 palms) revealed accurate conformity with phenotype data. The predicted protein sequence of the amplification product of primer DPM4 revealed four open reading frames (ORFs). Basic local alignment search tool (BLAST) analyses showed similarity with some regions in organisms known to exhibit gender genes. Male palms showed a single melt peak in quantitative PCR (qPCR), as opposed to the female palms that showed two closely related melt peaks. Marker DPM4 has been validated with 192 full‐sib palms of known phenotype for the sex gene and proven efficient for marker‐assisted selection of male and female palms in seedling propagation and popularization in Phoenix spp.

Somaclonal variation refers to any phenotypic or genotypic modifications that arise from in vitro culture. In the oil palm, it is characterized by fruit mantling and abnormal vegetative growth. Tissue culture remains the only means of micro propagation of oil palm as its biological characteristics do not allow for vegetative propagation by conventional means. The early success of plantlets production inspired many oil palm organizations to explore in vitro propagation technique. Though oil palm tissue culture is already well established, it is still faced with many challenges. Prominent among them is somaclonal variation which was first reported in 1986. They are only detectable when the palms start flowering; that is, after two to three years in the field. It has not been possible to fully eliminate or circumvent floral abnormality in the oil palm. However, the adoption of several measures such as reducing hormone level, avoiding fast growing callus and, reducing culture period, have reduced the problem to manageable levels of < 5%. Possible causes and factors influencing somaclonal variation in the oil palm are discussed.

The RAP2.6L is a member of the ERF (ethylene response factor) subfamily β‐4 of the ERF/APETALA2 transcription factor gene family. These preliminary studies seek to investigate the mRNA level of RAP2.6L gene in oil palm (Elaeis guineensis) leaf, inflorescence explants and the calli produced from them, with a view to understanding the molecular basis of direct and indirect organogenesis. Callus was induced and proliferated from non‐chlorophyllous leaf and immature inflorescence tissues using Murashige and Skoog medium. This was supplemented with different concentrations of auxins: 2,4‐D and NAA, ranging from 100‐120 mg/l and 170‐200 mg/l respectively. The times taken for callus induction, percentage callusing explants and weight of fresh callus after 20 weeks of culture initiation were recorded. Callus production was seen to vary in time of initial response and quantity produced for both 2,4‐D and NAA treatments. The leaf tissues yielded more callus in less time than the inflorescence tissues. Treatment 100mg/l 2,4‐D was effective in producing callus in 11 % of leaf explants, while 185 mg/l NAA was more effective in producing callus in 8 % of same. The level of RAP2.6L mRNA was measured with reverse transcription polymerase chain reaction (RT‐PCR). The results obtained indicated that there was no significant difference in the RAP2.6L mRNA level among the explants and associated calli, suggesting that both explants were equally amenable to indirect organogenesis.