Volodymyr Vitenko*, Volodymyr Shlapak, Iryna Kozachenko, Volodymyr
Kulbitskyi, Svitlana Maslovata, Sergiy Koval, and Oleh Lazariev

Department of Forestry, Uman National University of Horticulture, 1 Instytutska Str., 20305
Uman, Ukraine. *E-mail: uman.vitenko@ukr.net

Based on the processing of literary sources and our own research, we studied the features of
grafting ornamental forms of Morus alba: ′Pendula′, ′Globosa′, ′Pyramidalis′, ′Contorta′, ′Macrophylla′
and ′Tatarica′. It is proposed to distribute these ornamental forms according to the grafting
and budding dates: winter – the second or the third decade of February – the first decade of
March; spring: early spring (the second or the third decade of March); spring the average (the
first – the second decade of April); late spring (the third decade of April – the first to the second
decade of May); summer – the end of the first decade of July is the first decade of August. It is investigated
that the best period for its holding is the first and the second decade of April. It is determined
that the most effective method of winter grafting is improved copulation, which was carried
out in early March – the highest average splicing of various components after grafting of these
plants was observed in forms ′Tatarica′ (70 %) and ′Macrophylla′ (60 %). When grafting plants by
splitting in these forms, the highest average splicing is also noted – compared 61 % and 54 %.
The highest splicing results of grafted plants during their spring grafting were also obtained by
applying the improved copulation method in forms ˊTataricaˊ – (88–92 %), ˊPendulaˊ – (78–84 %)
and ˊMacrophyllaˊ – compared 65–75 %. The largest number of splices of grafted plants during
grafting by applying the method for behind the barkis noted in form ˊTataricaˊ (87–91 %, a little
lower – in ˊPendulaˊ (73–77 %) and ˊMacrophyllaˊ – compared 64–72 %. It was investigated that
the wild plant (M. alba) and its studied ornamental forms resemble their internal structure and the
grafting sites are quickly spliced and are completely covered with a protective fabric before the
onset of the rest period.

Stoyan Stoyanov

Wildlife Management Department, University of Forestry, 10 St. Kliment Ohridski Blvd., 1797
Sofia, Bulgaria. E-mail: stoyans@abv.bg

Craniometric characteristics and sexual dimorphism have been described for many carnivore
species in Europe. However, very few studies have focused on cranial variability of golden jackal
(Canis aureus Linnaeus, 1758) in Europe, despite its expanding distribution in recent decades.
Although numerous works have addressed sexual dimorphism in carnivore skull size, only few
studies have attempted to study dimorphism in overall cranial shape. The present study proposes
the first comprehensive analysis of golden jackal skull morphometry in Bulgaria, trying to clarify
shape and size related cranial variability and differentiation. Extensive morphometric data of jackal
skulls were analysed by applying recently developed statistical tools to answer the following
questions: (i) is there a geographic variation in skull size and shape among golden jackal population
in Bulgaria, (ii) are there age-related cranial differences, and (iii) how pronounced is the sexual
dimorphism in skull shape and size? A total of 176 skulls of golden jackals, collected all over the
country, were analysed by univariate and multivariate statistical methods. Principal component
analysis and linear discriminant analysis were applied on the standardized and log-transformed
ratios of the original measurements to clearly separate specimens by shape and size. Skulls of
golden jackal in Bulgaria show considerable individual variability but weak intrapopulation differentiation.
The differences in shape and size of the jackal skulls, as far as they exist, are age-related,
but only juveniles younger than 11 months could be easily distinguished. Subadult and
adult jackals largely overlap in skull size and shape. Sexual dimorphism in jackal skulls is weakly
pronounced, with older males a little bit larger than females. The results of the present research
are consistent with recent genetic and morphological studies and give new insights on patterns in
cranial variability and population structure of golden jackal in Bulgaria.

Vasil Kolev (1)* and Galerida Raikova (2)

1. University of Forestry, Faculty of Forestry, Wildlife Management Department, 10 Kliment
Ohridski Blvd., 1797 Sofia, Bulgaria. *E-mail: vassilkolev@ltu.bg
2. ‘St. Kl. Ohridski’ Sofia University, Faculty of Biology, Department of General and Applied
Hydrobiology, 8 Dragan Tzankov Str., 1164 Sofia, Bulgaria. E-mail: galerida@abv.bg

The set of reproductive parameter estimates, determined by this study, gives the first quantitative
estimates for this population. The study was conducted in the autumn during the period of
years 2010–2011. A total of 97 fish specimens were caught by electrofishing. The study found that
both sexes mature sexually in the second year. The females become sexually mature, once they
reach a length of 122 mm and 25 g weight. The males become sexually mature once they reach
a length of 90mm and 7 g weight. The fecundity of barbel population from the Chepinska River
ranges from 2000 to 17,969 eggs. The average fecundity was 5246 eggs. The absolute fecundity
was positively correlated with the growth of the length and mass of the fish. Consequently, the
five years old Maritsa barbels had the highest fecundity rate. The average values of the relative
fecundity were 115 eggs per kg.

Margarita Georgieva*, Gergana Zaemdzhikova, Plamen Mirchev,
and Georgi Georgiev

Forest Research Institute, Bulgarian Academy of Sciences, 1756 Sofia, 132 St. Kliment Ohridski
Blvd., *E-mail: margaritageorgiev@gmail.com

The hatching dynamics of larvae of early developing phenological form of pine processionary
moth (Thaumetopoea pityocampa) based on 93 egg batches was monitored under laboratory
conditions. The egg batches were collected on July 12, 2018 in a 30-year-old Pinus nigra plantation,
at an altitude of 450 m in the region of Fotinovo village, Kirkovo State Forestry, Eastern
Rhodopes. Newly hatched larvae started appearing at the beginning of July 2018, and continued
for a month, until August 8, 2018. The peak lasted for 13 days, from the 19th to 31th of July, during
which 80.6 % of the larvae hatched. Field observations conducted in parallel, showed that the
larval development in the studied habitat lasted for about three months.