ISSN 1021-4437, Russian Journal of Plant Physiology, 2009, Vol. 56, No. 5, pp. 647–653. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © I.N. Tret’yakova, A.C. Ivanitskaya, A.N. Ivanova, A.V. Barsukova, 2009, published in Fiziologiya Rastenii, 2009, Vol. 56, No. 5, pp. 718–725.
Androgenesis in vitro is a phenomenon of cultured
sporogenic cell switching from the gametophytic path-
way of development to sporophytic one. This is one of
the very promising directions for production of haploid
and dihaploid regenerants in current biotechnological
studies. This phenomenon is actively examined in vari-
ous angiosperms [1–6], whereas such investigations are
only started for gymnosperms [7, 8].
Siberian larch (
Ledeb.) is one of prin-
cipal forest-forming trees in Siberia. Its stands are fre-
quently destroyed by various pest insects, the larch gall
Mam. et Nik.) in particular.
Female larch midges lay eggs in the bases of brachy-
blasts (shortened shoots) that begin to produce needles
; thereafter, the bud is transformed into a large scaly
cone-shaped teratic gall (pest-induced modiﬁcation of
organ structure) [10, 11]. Heavily infested trees did not
essentially have buds older that two years, and micro-
and macrostrobiles (respectively male and female stro-
biles, i.e., modiﬁed shortened shoots carrying special-
ized leaves, sporophylls producing sporangia, i.e., gen-
erative organs) did not arise .
In each natural larch stands, up to 1–3% of trees are
genetically resistant to larch gall midge . Some
researchers believe that this is related to difference in
the content of phytohormones in trees resistant and sen-
sitive to the pest .
Propagation of trees resistant to entomopathogens is
especially important. Elaboration and application of
modern biotechnologies, such as somatic embryogene-
sis and androgenesis in vitro, permits a production of
Siberian larch pure lines resistant to larch gall midge
and their mass propagation.
Many plant species are known to be hormone-
dependent during their in vitro culturing and induction
of androgenesis in vitro [13, 14]. Since it is a rather
This paper is devoted to the memory
of famous plant physiologists
Dr. Elena Grigor’evna Minina
Phytohormone Content in Microstrobiles
and Androgenic Callus of Siberian Larch
I. N. Tret’yakova
, A. C. Ivanitskaya
, A. N. Ivanova
, and A. V. Barsukova
Sukachev Institute of Forestry, Siberian Division, Russian Academy of Sciences,
Akademgorodok, Krasnoyarsk, 660036 Russia;
Siberian Federal University, Krasnoyarsk
Received April 9, 2008
—Androgenesis in vitro in plants is a phenomenon of developmental switching of male generative
cells, microspores, from their normal gametophytic to sporophytic pathway. We obtained androgenic callus and
embryoids (embryo-like structures derived from microspores) of the conifer plant, Siberian larch (
Ledeb.) in the in vitro culture. The immune-enzyme analysis of the hormonal balance of larch androgenic cul-
tures showed a substantial increase in the content of all phytohormones, especially cytokinins and ABA, as
compared with initial explants (microstrobiles). This was evidently related to active cell divisions and embryoid
formation. A comparison of androgenic cultures derived from trees nonifested and infested with larch gall
Mam. et Nik.) revealed a cytokinin content increase (by two times) and an ABA
content decrease (by two times), which indicates more intense growth of cultures derived from healthy trees.
Phytohormone content in the androgenic callus was compared with their accumulation in the embryos of larch
seeds harvested from noninfested trees. We concluded that successful growth of androgenic cultures and embry-
oid formation demand an additional medium supplement with auxins (not more than 0.5 mg/l).
Key words: Larix sibirica - immune-enzyme analysis - zygotic embryo - endosperm - androgenesis in vitro -
morphogenic callus - embryoid
: MS—Murashige and Skoog nutrient medium.