"Zafar Iqbal completed National College of Business Administration & Economics,in Statistics in the year 2013.He was a Visiting Professor University of Sargodha, Gujranwala Campus, Pakistan October 2013 to present .His intrest in teaching as Applied Statistics to M.Phil Management Sciences and data Analysis through SPSS and EVIEWS to M.Phil Management Sciences. "


The present studies were undertaken to study the variability amongst isolates of Penicillium digitatum and P. italicum collected from Western Australia. The effect of different concentrations of Nitric oxide (NO), salicylic acid (SA) and Methyl jasmonate (MeJ) on P. digitatum causing green mould on Washington navel orange was also investigated. Four isolates of P. digitatum and P. italicum prefixed as PD-1, PD-2, PI-3 and PI-4 were tested on three different media including citrus peel agar (CPA), Potato dextrose agar (PDA) and Malt extract agar (MEA). PI-4 proved to be fast growing showing 56.15 mm radial growth as compared to PD-1, PD-2 and PI-3 which exhibited 44.07, 40.48 and 52.85 mm, respectively. CPA proved to be the best medium for the growth of P. digitatum and P. italicum showing overall radial growth of 59.25 mm in contrast to PDA (48.33 mm) and MEA (37.58 mm). Treatment of Washington Navel fruit with SA (0.1, 1.0, 2.0 mM), MeJ (0.1, 1.0, 2.0 mM) and NO (5, 25, 50 µl) revealed that NO 50 µl inhibited the colony growth of P. digitatum on artificially inoculated Washington navel fruit by 43.90% compared to SA 2.0 mM (34.08%) and MeJ 2.0 mM (27.57%). NO 50 µl also proved successful to inhibit the wound rotting incidence by 63.56%. The present study suggests that the control of green mould of citrus is possible by use of NO or natural elicitors.
Keywords: Washington navel, Penicillium digitatum, P. italicum, isolates, elicitors, Nitric oxide.