Effect of Seasons, Gender and Agrobacterium rhizogenes Strains on Adventitious Root Induction of Male and Female Juniperus communis L.

Scrutinizing of different aspects in vegetative propagation of Iranian J. communis L. is of prime importance in order to prevent extinction of such valuable conifer. In this research, the effects of different seasons, gender, different chemical compounds (IBA, PBZ, putrescine and sodium nitroprusside) and three strains of Agrobacterium rhizogenes on ex-vitro rooting capacity of male and female J. communis L. were evaluated. Rooting of semi-hard wood J. communis L.cuttings in autumn were notably successful either in female or male plants. Research results indicated that cutting gained in September provides the highest rooting percentage in female plants while no significant differences in rooting ability were found in male plants which were collected in December and September. There were a female-biased root induction trends between genders. Treatment of female cuttings with IBA declined rooting to the half, even in male cuttings it completely suppress root induction ability compared to control plants. Our empirical evidence on presence of genetic difference in random amplified loci of male and female plants to some extent can explain the difference in rooting competency which can be influenced by difference in genetic make up. A4 strain of A. rhizogenes managed to yield 53.5% rooting compared to the other strains in male plants. The gender-mediated adventitious root formation of J. communis L. which has supported with some genetic evidence will pave the way for further fundamental studies to delineate the missing molecular key of rooting mechanisms.