NECTAR SECRETION AND HONEY POTENTIAL OF HONEY

Vol. 48 No. 1 2004
Journal of Apicultural Science
5
NECTAR SECRETION AND HONEY POTENTIAL
OF HONEY-PLANTS GROWING UNDER POLAND’S
CONDITIONS - Part XIV
Boles³aw
Jab³oñski,
Zbigniew
Ko³towski
Institute of Pomology and Floriculture, ul. Kazimierska 2, 24-100 Pu³awy
Received 20 November 2003; accepted 27 December 2003
S u m m a r y
The beekeeping value of 11 tree and bush species growing on a podzolic soil at the Apiculture
Division, Institute of Pomology and Floriculture in Pu³awy was studied in the years 1999-2003.
Those plants were found to yield nectar and pollen to bee-related insects and to be eagerly
visited from the morning until the evening especially by the honeybee. The amount of sugars
supplied by 10 flowers of Sorbus aucuparia averaged 1.3 mg with the honey output from the
stand of 1 ha of those trees being estimated at 14 kg. The respective values for other species
were 2.0 mg (and 68 kg) for Amorpha fruticosa, 4.2 mg (and 27 kg) for Crataegus pediculata,
4.3 mg (and 36 kg) for Acer campestre, 4.6 mg (and 13 kg) for Eleagnus angustifolia, 5.2 mg
(and 65 kg) for Physocarpus opulifolius, 5.3 mg (and 22 kg) for Prunus divaricata, 6.0 mg (and
42 kg) for Ailanthus altissima, 8.6 mg (and 6 kg) for Catalpa ovata, 15.8 mg (and 7 kg) for
Persica vulgaris, 16.3 mg (and 11 kg) for Armeniaca vulgaris. All the mentioned species
including those with lower nectar efficiency are a valuable component of our melliferous flora.
Keywords: honey plants, blooming, nectar secretion, bee foraging.
INTRODUCTION
14th
Here is reported the
part of the
study on nectar secretion by plants under
Poland’s conditions. The study contains
data collected for further 11 tree and bush
species. Persica vulgaris and Armeniaca
vulgaris are grown on a small scale in this
country as fruit trees. The remaining species are grown in parks and in public green
areas and some (Sorbus aucuparia, Acer
campestre, Prunus divaricata) also occur
in the wild. In the beekeeping literature
(Gluchov 1955, Lipiñski 1982 among
others) they are regarded as good or fairly
good melliferous plants. With the exception of Sorbus aucuparia (Szklanowska
1978) no detailed assessment has been
made in this country with regard to their
nectar output so this study is an endeavour
to this effect.
MATERIAL AND METHODS
The study was performed in the years
1999-2003 on trees and bushes 3 to 45
years old from their planting date. They
grew singly in the park, in apiary stands
and in garden plots located at the site of
the Apiculture Division in Pu³awy. The
soil was podzolic essentially not fertilized.
The management of the trees was limited
to indispensary pruning or to the cutting of
redundant branches and shoots. The records of blooming and of insect visitation
were taken using methods currently used
in beekeeping botany (inter alia Demianowicz and H³yñ 1960, Demianowicz
et al. 1963). Abundance of nectar secretion
was measured using the pipette method
(Jab³oñski 2002).
6
Vol. 48 No. 1 2004
Journal of Apicultural Science
7
8
RESULTS
Blooming. The blooming time of
Armeniaca vulgaris, Prunus divaricata and
Persica vulgaris occurred in April, that of
Acer campestre, Crataegus pediculata and
Sorbus aucuparia in May, that of
Physocarpus
opulifolius,
Amorpha
fruticosa, Eleagnus angustifolia and Ailanthus altissima in June and Catalpa ovata
bloomed from approximately mid-June to
the end of July (Table 1). The duration of
the blooming period of the majority of the
plants was 8-12 (15) days. Only
Physocarpus opulifolius and Amorpha
fruticosa bloomed for ca. 20 days and the
blooming period of Catalpa ovata lasted as
long as 40 days.
The number of flowers produced on a
plant ranged extensively from 2(10) thousand (Persica vulgaris, Armeniaca
vulgaris, Catalpa ovata) through 20(100)
thousand (Prunus divaricata, Eleagnus
angustifolia) to as many as 200-500(900)
thousand (the remaining species). The differences over the years of the study within
a species ranged from 20(80)% to
200(300)%. The majority of the trees and
of the bushes flowered most profusely in
the exceptionally warm year of 2003, (Armeniaca vulgaris, Persica vulgaris and
Prunus divaricata were pruned).
Foraging by insects. The trees and bushes
under the study were visited mainly by the
honeybee. Although rare, there were also
bumblebees and wild solitary bees among
the visitors. The weather being favourable,
the visitation lasted the whole day with the
peak intensity in the noon. Nectar and pollen foragers were always eager visitors of
Armeniaca vulgaris, Prunus divaricata,
Persica vulgaris, Crataegus pediculata,
Physocarpus
opulifolius,
Amorpha
fruticosa, Eleagnus angustifolia and Catalpa ovata. Sorbus aucuparia was also visited in great numbers provided the weather
was warm and humid. Not many bees were
seen on Acer campestre or Ailanthus
altissima, though.
Nectar secretion. The concentration of
sugars in nectar being always strongly dependent on the current relative air humidity
ranged widely, mostly from ca. 20(10-30)%
to ca. 50(40-70)%. The earlier blooming
species (in April and May) generally had a
lower concentration of sugars in nectar than
did the later flowering species (in June and
July).
The average amount of sugars secreted
in nectar by 10 flowers was ca. 1.3 mg in
Sorbus aucuparia ca. 2.0 mg in Amorpha
fruticosa, 4-5 mg in Crataegus pediculata,
Acer campestre, Eleagnus angustifolia,
Physocarpus opulifolius and Prunus
divaricata, 6-9 mg in Ailanthus altissima
and Catalpa ovata and 16-17 mg in
Persica vulgaris and Armeniaca vulgaris.
The differences in the abundance of
nectar secretion by the flowers of the trees
and bushes in the study between study
years were mostly 20-40 (80)%, and only
for Ailanthus altissima they exceeded
200% and for Crataegus pediculata 400%.
Obviously, those discrepancies were related to weather conditions prevailing at
blooming.
Sugar and honey potential. The output of
nectar sugars per single tree or bush and per
blooming period of the species studied
ranged from less than 10 to more than 350 g
(Table 1). Obviously, it depended on
blooming abundance of the plant and the
nectar secretion rate of its flowers.
When calculating the output of sugars
per blooming period and per unit area the
number of trees or bushes per 1 ha was assumed that would ensure good access of
sunlight to guarantee blooming abundance
and high nectar output. The calculated
sugar outputs (kg per 1 ha) varied substantially over the years: from 5 to 8 kg for Catalpa ovata, from 4 to 12 kg for Persica
vulgaris, from 7 to 14 kg for Armeniaca
vulgaris, from 8 to 21 kg for Eleagnus
Vol. 48 No. 1 2004
Journal of Apicultural Science
angustifolia, from 10 to 17 kg for Sorbus
aucuparia, from 10 to 31 kg for Prunus
divaricata, from 7 to 57 kg for Crataegus
pediculata, from 27 to 47 kg for Acer
campestre, from 26 to 71 kg for Ailanthus
altissima, from 62 to 67 kg for
Physocarpus opulifolius and from 50 to
91 kg for Amorpha fruticosa.
The sugar output increased by 25%, or
converted to the output of honey containing 20% of water (the water content of mature honey) is the so-called honey potential
of the plant. Of importance are also the
so-called daily honey potentials. They are
calculated by dividing the combined output
by the number of days equal to 75% of the
length of the blooming period of the plant.
The values thus obtained are a good representation of the daily outputs at full bloom.
The mean daily honey potential thus estimated was (kg per 1 ha) ca. 0.2 kg for Catalpa ovata, ca. 2 kg for Persica vulgaris,
Armeniaca vulgaris and Eleagnus
angustifolia, 3 kg for Sorbus aucuparia,
ca. 5 kg for Prunus divaricata, Ailanthus
altissima, Physocarpus opulifolius, Acer
campestre and Crataegus pediculata, and
12 kg for Amorpha fruticosa. The daily
amounts of nectar offered to insects (not
converted to honey containing 80% of sugars) are always much higher since nectar
usually contains much more than 20% of
water.
DISCUSSION
Some of the results obtained in this
study can be confronted with literature
data. When compared to the data reported
by Szklanowska (1978) our data on nectar secretion by the flowers of Sorbus
aucuparia turned out to be nearly 50%
lower. The reason for those discrepancies
may be a different plant material, different
environment and different years of study.
The results from this study on the honey
potential of Persica vulgaris and Amorpha
9
fruticosa do not depart from those reported
by Simidèev (cited after Petkov 1979)
and obtained under Bulgaria’s conditions.
Instead, the values of that trait for Acer
campestre can be regarded as being in full
agreement with the information supplied
by Drašar and Kodoñ (1975). They were
much lower, though, than the data reported
by Gluchov (1955) being only 5% of
Gluchov’s figures. A relatively low honey
potential of Persica vulgaris and Catalpa
ovata was mainly due to the small number
of flowers per unit area which was in turn
related to the pruning of the former and the
sparse flowering of the latter.
CONCLUSIONS
The tree and bush species investigated
in this study supply nectar and pollen to insects in the period from early spring to the
end of July. Their flowers are mainly visited by the honeybee and by wild bee-like
insects. The weather permitting, foraging
lasts from the morning till the evening.
Ten flowers secreted the following average amounts of sugars during their lifetime: Sorbus aucuparia 1.3 mg, Amorpha
fruticosa 2.0 mg, Crataegus pediculata
and Acer campestre 4.3 mg, Eleagnus
angustifolia
4.6
mg,
Physocarpus
opulifolius 5.2 mg, Prunus divaricata 5.3
mg, Ailanthus altissima 6.0 mg, Catalpa
ovata 8.6 mg, Persica vulgaris 15.8 mg,
Armeniaca vulgaris 16.3 mg.
Based on the blooming abundance of
plants and nectar secretion rate of flowers
the average sugar efficiencies of Catalpa
ovata, Persica vulgaris, Armeniaca
vulgaris, Eleagnus angustifolia and Sorbus
aucuparia came within 6 to 14 mg/ha,
those of Prunus divaricata, Crataegus
pediculata, Acer campestre and Ailanthus
altissima ranged from 20 to 40 kg/ha and
those of Physocarpus opulifolius and
Amorpha fruticosa were from 60 to 70
kg/ha.
10
All the tree and bush species including
those with lower nectar efficiency are a
valuable component of our melliferous
flora. Some of them such as Amorpha
fruticosa or Prunus divaricata are suitable
for converting to beekeeping use of various
patches of idle land, very poor land including.
REFERENCES
Demianowicz Z., H³yñ M. (1960) Porównawcze badania nad nektarowaniem
17 gatunków lip. [Comparative study on the
nectar secretion in 17 linden species]
Pszczeln. Zesz. Nauk., 4(3-4):133-152.
Demianowicz Z., Jab³oñski B.,
Ostrowska W., Szybowski S. (1963)
- Wydajnoœæ miodowa wa¿niejszych roœlin
miododajnych w warunkach Polski. Cz. II.
[Honey
potential
of
the
major
honey-producing plants in Poland. Part II]
Pszczeln. Zesz. Nauk., 7(2):95-111.
Drašar J., Kodoñ S. (1975) - Vèeli pastva.
Statni Zemed. nakl., Praha.
Gluchov M.M. (1955) Waniejšyje
miedonosnyje rastienia i sposoby ich
razviedienia. Gosud. Izdat. Sielsk. Lit.
Moskva.
Jab³oñski B. (2002) - Notes on the
method to investigate nectar secretion rate
in flowers. J. Apic. Science, 46(2):117-125.
Lipiñski M. (1982) - Po¿ytki pszczele i
miododajnoœæ roœlin. [Honey pastures and
honey output of plants] Wyd. III. PWRiL,
Warszawa.
Petkov W.G. (1979) - Medonosni rastenia.
Zemizdat, Sofia.
Szklanowska K. (1978) - Nektarowanie
niektórych drzew i krzewów w warunkach
Polski [Nectar secretion of some trees and
bushes under Poland’s conditions].
Pszczeln. Zesz. Nauk., 22:117-128.
NEKTAROWANIE I WYDAJNOŒÆ MIODOWA ROŒLIN
MIODODAJNYCH W WARUNKACH POLSKI - Czêœæ XIV
Jab³oñski
B.,
Ko³towski
Z.
S t r e s z c z e n i e
W latach 1999-2003 badano wartoœæ pszczelarsk¹ 11 gatunków drzew i krzewów rosn¹cych
na glebie bielicowej w Oddziale Pszczelnictwa ISK w Pu³awach. Stwierdzono, ¿e roœliny te
dostarczaj¹ owadom pszczo³owatym nektaru i py³ku i s¹ chêtnie odwiedzane od rana do
wieczora, zw³aszcza przez pszczo³ê miodn¹. Iloœæ cukrów dostarczana przez 10 kwiatów
jarz¹bu pospolitego wynosi³a œrednio oko³o 1,3 mg (a wydajnoœæ cukrów z 1 ha powierzchni
zajêtej tymi drzewami oceniono na oko³o 14 kg), amorfy krzewiastej odpowiednio - 2,0 mg (i
68 kg), g³ogu szkar³atnego - 4,2 mg (i 27 kg), klonu polnego - 4,3 mg (i 36 kg), oliwnika
w¹skolistnego - 4,6 mg (i 13 kg), pêcherznicy kalinolistnej - 5,2 mg (i 65 kg), œliwy a³yczy - 5,3
mg (i 22 kg), bo¿odrzewu gruczo³owatego - 6,0 mg (i 42 kg), katalpy ¿ó³tokwiatowej - 8,6 mg (i
6 kg), brzoskwini pospolitej - 15,8 mg (i 7 kg), moreli zwyczajnej - 16,3 mg (i 11 kg).
Wszystkie wymienione gatunki, nawet te o ni¿szej wydajnoœci nektarowej, stanowi¹ cenny
sk³adnik naszej flory miododajnej. Niektóre z nich, jak amorfa krzewiasta czy œliwa a³ycza,
mog¹ byæ wykorzystywane do pszczelarskiego zagospodarowywania ró¿nych wolnych
skrawków gruntów.
S³owa kluczowe: roœliny miododajne, kwitnienie, nektarowanie, oblot przez pszczo³y.