Hormonal Basis of ‘Shees’ Fruit Abnormality in Tissue Culture Derived Plants of Date Palm

Shees' fruit abnormality manifested as cluster of small fruit-like structures on a single peduncle occurs at a high frequency in tissue culture derived plants of date palm. The abnormality is akin to parthenocarpy, which is known to be caused by altered hormone profile of flowers/fruits in many species. This study was conducted to elucidate the hormonal profile of date palm flowers and early fruits and to identify the hormones associated with shees' fruit formation. Hormone levels in young flowers/fruits of normal and shees'-bearing plants of cultivars Barhy' and Nabtet-Saif' were studied with HPLC at the time of pollination and subsequently after 10 and 20 days. In all these samples, out of seven hormones detected by HPLC, levels of indole-3-acetic acid (IAA) and gebberellic acid (GA3) were significantly higher, while that of a kinetin-like' compound and an unknown compound were significantly lower in shees' flowers/fruits as compared to the normal counterparts. Other three unknown compounds did not show significant variations between normal and shees' fruits. Kinetin-like compound showed the same elution properties as kinetin standard during HPLC procedures. The compound was purified and an attempt was made to characterize the molecule with gas chromatography-mass spectrometry (GC-MS). On the basis of Wiley-229 library hit (entry 101383) the compound was identified as Benzeldehyde, 2-hydroxy-[(2-hydroxyphenyl) methylene] hydrazone with formula: C14H12N2O2 and Mol weight: 240. We have tentatively designated the compound as BHH and are reporting the occurrence of this compound for the first time in date palm. Copyright 2015 Friends Science Publishers