production of honey bee colonies

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SU M MARY. Fofty colonies of Apis mellifera macedonica ... (Nolan, 1925; Braun, 1942; Woyke, '1984), but only a few included queens 3- or 4-years old in theirĀ ...
01995IBRA

Journal of Apicultural Research 34(1):9-14 (1995)

Brood and honey production of honey bee colonies requeened at vanous frequencies MaRtn Kosranetou-Dervttnrutoou' ; t; Aruonels Txnaswoutou'' Dtnittrntos Tsettos' ; Korustaurtnos BLnoENopoutoso

'National Agricultural Research Foundation, Agricultural Research Station of Halkidiki, N Moudania 632 00, Greece 'Laboratory of Apiculture-Sericu lture, School of Agriculture, Aristotle University of Thessaloniki, Greece oNational

Agricultural Research Foundation, Cereal Institute, 570 01 Thermi, Thessaloniki, Greece

(Received 28 SePtember 1993, accepted subject to revision 30 December 1993, accepted for publication 9 November 1994)

"Author for correspondence

SU M MARY Fofty colonies of Apis mellifera macedonica were established in Greece with naturally-mated sister queens, two frames of sealed brood and 2 kg of bees, and requeened either every year (A), every two years (B), every three years (C), or left to replace their queens through supersedure (D). All colonies were managed in the same way during the seven-year experiment. Brood area was significantly higher in groups A and B than in C or D, except for the first two years, During the first three years there were no significant differences in honey production between any of the

groups, but group D subsequently produced significantly less honey than all other groups. There were generally no significant differences in

each year's honey production between colonies in groups A, B or C, suggesting that requeening every two or three years is adequate.

Keywords: queen honey bees, Apis mellifera macedonica, requeening, age, brood rearing, honey production, Greece

Kostarelou-Damianidou; Thrasyvoulou; Tselios; Bladenopoulos

10

INTRODUCTION It is

commonly accepted that the age of a queen honey

bee determines her performance, and bee colonies that are not requeened annually seldom produce good honey crops. Howeve[ few objective data exist to sup-

full-depth hive bodies, and four frames for those with one. Protein supplements were not provided since bees collected and stored plenty of pollen during spnng. All colonies were treated alike. They were all opened

port this contention. Most studies of the effects of

on the same day and were examined every three

older oueens have been based on comoarisons

weeks for queen replacement, brood diseases, avarr-

between colonies headed by queens 1- to 2-years old (Nolan, 1925; Braun, 1942; Woyke, '1984), but only a few included queens 3- or 4-years old in their experiments (Szabo & Lefkovitch, 1989; Diehnelt, 1986; Cavojsky, 1 982). There have been no studies comparing supersedure and younger queens. More surprisingly, the data do not fully support the conventional

wisdom on the poor performance of colonies with aged queens. Szabo and Lefkovitch (1989) did not show differences in honey or brood production among colonies headed by 1-,2- or3-year-old queens. Similarly, Cavojsky (1982) found no differences in 4-year-

old and younger queens. The alternative view, that sometimes young queens are poor while some older

queens lay well for several seasons in succession (Cale et al., 1978), is not supporled by enough research data.

We conducted a study on the performance of 40 colonies that were requeened at various frequencies for seven consecutive years, and recorded their brood and honey production in order to determine the effects of queen replacement frequency on brood and honey

ability of space for brood rearing and food storage. Combs with foundation were given to colonies which needed more space. During April and May all colonies were checked for swarm cells every week. Swarming was prevented by the removal of any occupied queen cell during the swarming season, but despite these efforts two colonies swarmed. The swarms were captured and rejoined with their parental colonies. Strengthening and removal of brood and population were not undedaken. All colonies, healthy or diseased, were treated at the

same time. Varroa was controlled with malathion (1985-1989) and fluvalinate (1989-1991) during autumn of each year. Chalkbrood was prevented by the destruction of affected combs, by good ventilation of hives, and by often removing the mummies from the floorboard. No chemotherapeutic agent was used against nosema disease, tracheal mite disease, American or European foulbrood, since these diseases were never found in the exoerimental colonies.

oroduction.

The area of brood was measured monthly from May to November every year by means of a clear acrylic plastic (Plexiglas) grid(4x4 cm), estimating that 4.28 cells

MATERIALS AND METHODS

occupy 1 cm'of comb surface. The amount of honey extracted from each colony was calculated annually from the difference in comb weioht before and after

This investigation was conducted at the Agriculture Research Station of Halkidiki. Greece, between June 1985 and May 1992. Forly colonies of Aprs mellifera macedonica were used. They all received newly emerged and naturally-mated sister queens. Each colony began with two frames of sealed brood and 2 kg of bees (about 20 000 bees per colony). Colonies were grouped in four treatments of 10 each, designated as A, B, C and D. Colonies of group A were requeened every year (1 985-1 991 ), group B every second year (1 985, 1 987, 1 989, 1 991 ), group C every third

year (1985, 1988, 1991), and group D were left to

requeen themselves (supersedure). All requeening was done in May. Numbered plastic discs were glued on to the thoraces of the queens to ensure proper identification and to determine if the queen was replaced by the bees of the colony.

Experimental colonies were located in the same apiary but were simultaneously moved to three or four areas in each year for food. In seasons when the quantity of honey was insufficient for wintering, colonies were fed with heavy syrup made of two pads sugar to one of water (2 : 1). Each was given enough syrup so that they stored adequate amounts of carbohydrate for winter:

eight frames of sealed food for colonies with two

extraction.

Statistical analysis was performed using separate ANOVA analyses for each year. Differences among treatments were assessed by Duncan's Multiple Range Test. Correlation coefficients between brood production and honey yield were calculated for each group ano year.

RESULTS Brood production in consecutive years Our experimental period began in June and ended in May of the following year, with the exception of the seventh year which lasted from June to November. Five colonies of group D became weak and died in 1 988-1 989, two in 1 989-1 990 and one in 1 990-1 991 . The other groups did not lose any colony throughout the experiment. Averages and statistical analysis were calculated using the surviving colonies for group D.

Colonies had the highest amount of brood in May (table 1). The process of requeening that was carried out after the May measurement affected brood production in June. Colonies regained the losses in July, and extended their brood rearing until August when

Kostarelou-Damianidou; Thrasyvoulou; Tselios; Bladenopoulos

12

the brood area began to decrease. The brood area was least in November and February. During October of 1986, 1987, and 1989 brood area increased in all groups, due to the flowering of the shrubs Erlca yertrcillata and E. carnea. During the first two years, no significant differences were obseryed among groups in total brood production (table 1). The differences began from the third year

when groups A and B produced significantly more brood than groups C and D. From then, the superiority

of younger queens was apparent in their greater amount of brood production. No significant differences were found among colonies with queens 1- or 2-years old in any one year in either environmentally favourable (1989-1990) adverse (1990-1991) years.

or

Colonies with 3-year-old queens or supersedure

Honey production in consecutive years During the first three years of the experiment no signif-

icant differences in total honey production were observed between the four groups (table 2). Group D produced about half of the honey produced by the other groups in 1 988, and every year after 1 989 group D continued to produce significantly less honey than the other groups. Dead colonies of D group were eliminated from the study.

During 1989 colonies of group C with 2-year-old queens gave the highest amount of honey, approximately 24 times more than that produced by colonies of group D in 1991 . With the exception of 1989, no sig-

nificant differences were found among colonies headed by 1 -, 2- or 3-year-old queens.

queens produced significantly less brood than groups A or B in all comparable years (table

1):35.5% less during autumn (September-November), 35.8% less during February, and 46.2% less during spring (March-May).

Thus, colonies with younger queens were more populous and had more bees for the winter cluster. This larger working force resulted in an earlier production of brood in February and a greater increase in spring.

Goefficient of variability and correlations Colonies were more or less homogeneous during the first three years but after that the coefficient of variation (CV) of all groups increased significantly (table 3). The unfavourable conditions of the fourth year seemed

to affect the brood rearing among groups differently,

TABLE 2. Honey production (kg) of colonies requeened at different frequencies (i t s.e.), Colonies in each group were requeened as follows: A, annually; B, every 2 years; C, every 3 years; D, left to natural supersedure.

Year

Group A

Group B

985 1 986 1987 1 988 1 989 1 990

27.4 + 1.6 a

27.2 r1.5 a 33.1 + 1.4 a

991

57.9+4.6a

31.4 t 0.9 a 20.2 + 1.3 a 51.8 t 7.0 a 21.6+1.7 a 57.0 + 4.4 a

Total

236.6

242.5

250.6

120.1

Means'

33.8 a

34.6a

35.8 a

17.1 b

1

1

28.6 +2.3 a 32.6 x 1.3 a 21.O +2.6 a 49.5t5.7 a 19.4 x 1.4 a

' Means with different letters are significantly different from each other

Group C 27.7 +1.3a 31.8 + 1.1 a 23.8 t 1.3 a 21.8 + 1.6 a 73.2 x.10b 17.4 t2.2 a

54.2x.5.1a

Group D

t

28.5 1.1 a 32.6 + 1.2 a 23.5 r 1.4 a

11.5+1.3b 14.3 6.7

t 10.1 c t 0.3 b

elrATh

(P < 0.05)according to Duncan's Multiple Range Test

Comparisons were made within years

TABLE 3. Coefficient of variation (CV) of brood production of colonies requeened at different

frequencies. Colonies in each group were requeened as follows: A, annuallyl B, every 2 years; C, every 3 years; D, left to natural supersedure Group A

Years 985-1 986-1 1 987-1 1 988-1 1 989-1 1 990-1 1 1

986 987 988 989 990 991

19.5 17.9 15.5

Group B 20.1 17.1

18.0

27.1

17.2 19.6

18.7 19.6

Group G

/.c

Group D

to.o

16.6 17.9

20.6

21.7

|

zc.l

48.1

27.5 36.5

53.9 34.7

Requeening frequency and brood and honey production

11

TABLE 1. Brood area in cm' (x * s.e.) of colonies reqeened at different frequencies (1 cm'= 4.28 cells). Colonies in each group were requeened as follows: A, annually; B, every 2 years; C, every 3 years; D, left to natural supersedure, The ages of queens in each group are shown.

Month

198S1986 Group A 1-yr-old

Jun Jul Aug Sep Oct Nov Feb Mar Apr May

752t1og 645t195 1 517 r2og 1 072!168

1

1986-1987

B Group C 1-yr-old 1-yr-old

Group

771

Month

!114

1473+171

078r188

1 365 x.172

1 081

1

1

Group C

Group D

2-yr-old

2-yr-old

2-yr-old

513r92

754 + 1O4 1 570

165

Group B

-yr-old

1

x122

22OO x.221

1465+186

1 573

r131

925

t

190

1 757

t25O

2057 1249

1349t113

r137

1

446t156

1175 1 363a132 1 757

595 a 90

603

1

572+154

1 928

*182

1 275 +

t74

577

118

t65

t

t69

427 +86

5Og + 72

487

t36

1 187

r

115

142+26

149 + 21

141

r22

259

t

43

172 +26

160

t22

165

t25

'128

13

123 + 21

125

r25

533

523 x 46

478

t24 t64

126

692+91

668

t

560 + 49

497 +76

492

r.86

1 409+168 2597t'191

198&1987 Group A -yr-old

Jun 602t82 Jul 2245t216 Aug 1 568t 119 Sep 977 t 138 Oct 1 292+105 Nov 282+32 Feb 154t30 Mar 731 t60 Apr 1 373t 139 May 24721197 Means'

-yr-old

Group A

146+23 168+30

441

1

763

1

570+142 1 5O4 r'177

1 653

1

1 171

t

65

107t180

2 586

Means' 1044a

Month

r118

r

Group D

198$1990 1-yr-old

Jun 1 093t105 Jul 2381 *24 Aug 2264t80 Sep 629 t 109 Oct 27841287 Nov 430 t 85 Feb 509 + 70 Mar 2459t296 Apr 3346t343 May 31 7 +251 Means'1909a

t

145

1115t134

50

i

'1 438 137 2 493 +220

t133

1 195

187 x.34

1 081

t

t117

2084 x.258

174

1

t127 r24

059t94

2 198

!

184

1043a

976 a

1138a

Group D

Group A

Group B

S-yr-old

1-yr-old

2-yr-old

998 a

994 a

1 225

178

166t30

1

054r86

2 102 + 176 1052 a

1988-1988

B Group C 1-yr-old 3-yr-old

Group

1

680i135 t311

846

t

134

1 '111 + 333

963 r.247

2 029

1 965

t

248

1 454

x.135

1

1 352 +327

1 245

!217

858 1322

97

410t161 686+149

573t159

592

t

352 + 167

141

328 + 55

251 + 90

277

!30

+24

83t54

66t17

102r30 514 r147

608t156

x173

1

518t67

1 282

t145

1 270

i59

878 x.1O4

BB0

r

1 296 *.92

997r149

981

t

154

t25

797

r35

275

150t29 517t108

187 75

342

1 157

+43

t

r

131

80

152t56

50+8

18

r50

430 + 76

685

t

206

r

1 277

r

183

843 x.121

1 036 x.232

1 590

t227

1 021

2 696

t

504

2214 r2OG

2067t470

3 624

!604

3115t498

952 b

Group D

917 x.70

t

1 5O7

1

superseded

1

1 198

132

C 1-yr-old

Group

496r155

621 +71

2067 t2O9

a

Group A

1 154

!147 2289 t248 2504*196

1 297

184

1072 ab

952 b

1142 a

Group D

Group A

superseded

1-yr-old

998t1105 1370+1539 1 114+1 117

1

86

152

2992

t466

1001 b

t

598

64

40t14

tzt !zo

1342+442

t

314r189 352 * 185 896

t792

555 a

1990-1991

B Group C 1-yr-old 2-yr-old

Group

971

r

90

2322 +241 2 109 +267 710

2802

r

128

t315

1 829

t

339

2 672 x.306

2374 581

r398

t

138

2 416 r.343

515+99

419t116

526t82

522

t

129

2334t313

2294

!

421

3523 t47O 3 200

t

1901 a

300

1

t

'106

715 L72

t51

420 x.298

474

388t1 676

270 x41

187 1

008+85

1 482

t192

106+40

112 x 42

21O

109r912

528

371+1 156

2 941 a 561

1

2643 t481

225611

1869a

1032 b

147

r 40 r70

1 413 a 105

2925 1262 912 a

B Group D Group C 2-yr-old 3-yr-old superseded 1 382t108 1157t301 '1 1041310 1 723 x171 9791305 1 210+589 718 t102 436 r 133 635 t 773 507 r 56 299t102 320t235 291 r34 2OBt43 192+280 130t30 166166 160t0 144 t125 203 t 51 185 t 64 536+106 423176 555 t 191 1 434r109 987 1129 1 077 x.437 2758 t2O5 1 683 t 154 1 461 t945 Group

968 a

652 b

685 c

'Means with different letters are significantly different from each other (P < 0.05) according to Duncan's Multiple Range Test Comparisons were made separately each year

Requeening frequency and brood and honey production

IJ

TABLE 4. Correlation coefficients ftl between brood area and honey production for each group and year.

Group A

Years 1

0.44

1

985 986 1 987 1 988 1 989 1 990

0.35

1

Group G

-0.46

Group D

-U.UC

0.32

0.73*

o.32

u.4b

0.58

0.'13

0.71.

0.46 0.04

o.37

0.02

0.77*

0.84*

0.76* 0.89*

0.20

0.30

0.45

0.75*

o.21

-o.20

-u.52

991

Group B

. Significant at P 0.05

..SignificantatP0

01

contributing to a higher CV. This hypothesis is supporled by the data of 1989-1990, which shows the best

1988-1989 produced less brood than colonies that were requeened every year (group A) or every two

honey production during the experimental period. In

years (group B), but the differences were not significant. lt seems that the young queens in group C were

that year the CV of groups A and B dropped, while that of C and D remained high. The high CV of group D can be explained by the variability that existed among the fecundity of mother queens and those of supersedure daughters. The CVfor months, across years and groups, ranged from 6.1 % to 80.1 %o.For all groups, October, November and February were the months with ihe highest CV (52%,31%o and29%o respectively) and June, July and May the months with the lowest (20%, 21%o and 19o/o respectively). lt seemed that some queens continued laying eggs late into the autumn while others staded their brood production earlier in the following spring.

Factors other than the age of the queen, the food resources or the environmental conditions could contribute to that variation. Table 4 indicates that the correlation coefficients (r) are

highly variable, often being significant, weak or negative. The rvalues were not consistent in either good or bad years or in colonies with queens of either one, two or more years of age.

DISCUSSION Previous studies comparing colonies headed by '1 year-old and 2-year-old queens provided contradictory results. Nolan (1925), Braun (1942), and Woyke (1984) found that 1-year-old queens produced more brood and higher amounts of honey than colonies with 2-year-old queens. Szabo & Lefkovitch (1989) found no significant differences either in brood or honey production between such colonies. Brunnich (1922) and Diehnelt (1986) found higher rates of brood rearing in colonies headed by 2-year-old queens than in those with 1-year-old queens. We found no significant differences among 1-year- and 2-year-old queens in any combination of comparisons in 1986-1987, 1988-1989, 1989-1990 and 1990-1991 (table 1). The queens that replaced the 3-year-old ones of group C in

affected by the smaller colony population in their inherited colonies and consequently produced less brood, but subsequently managed to compensate and overcome ihe loss of the previous year. The decline of brood production in colonies headed by older queens was apparent only during their third year, when they produced significantly less brood than 1-

year-old (1987-1988, 1990-1991),

or

2-year-old

990-1 991) queens. Our results with older queens agree with those of Diehnelt (1986), but are contradictory to those of Szabo & Lefkovitch (1989) who found no significant differences among colonies headed by 1-, 2- or 3-year-old queens. The differences are (1

restricted to brood production, since we found that colonies with 3-year-old queens produced similar amounts of honey to colonies with 1- or 2-year-old queens (table 3). This result is not unexpected, since the correlation of honey production and brood area is variable and not always positive (table 4).

ln all comparisons and combinations, colonies with supersedure queens gave significantly less honey and brood than all the other groups. During the last years of the experiment (1 988-1 989, 1 989-1 990, 1 990-1 991 ) they produced 34.4%,20.9Vo and21 .4Vo of thetotal brood and 24.5o/o,36.2%o and 5% of the honey production of the other groups, respectively. Fudhermore, eight out of 10 colonies with supersedure queens were lost over the seven years of experiment.

The positive correlations indicate that honey yield increases with increasing amounts of brood. The correlation is variable since honey production depends upon factors such as the length of adult life, the individual productivity (Woyke, 1984), the time of the year (Szabo & Lefkovitch, 1989), and environmental factors (Bar-Cohen et a1.,1978; Louveaux, 1967; Genc & Aksoy, 1993) in addition to brood area. Negative correlations are attributed to the interaction between brood and environmental factors on honey production.

Kostarelou-Damianidou; Thrasyvoulou; Tselios; Bladenopoulos

14

Our correlations were estimated by the relationships

between the annual amount of brood and weight of honey that each group produced during the seven years of the experiment. The known differences in r values between the favourable and the adverse years (Bar-Cohen et a|.,1978; Genc & Aksoy, 1993) contributed further to variation of our coefficients. The

range of r values reported by several other authors (Woyke, 1984; Moeller, 1958; Soller & Bar-Cohen, 1967) concurs with our research.

The overall results of this research indicate that colonies with queens one or two years of age do not differ significantly in either brood or honey production. Colonies with queens three years of age produce less brood than colonies with queens aged one or two years, but not significantly less honey. Colonies that were left to supersede their queens produced significantly less brood, less honey and had difficulty in surviving adverse conditions. Requeening can be effective every two or three years. More research is needed with different races of bees, under different climatic conditions with different food resources to evaluate further this impor.tant aspect of bee husbandry.

REFERENCES The numbers given at the end of references denote entries in Aolcultural Abstracts. BAR-COHEN, R; ALPERN, G; BAR-ANAN, R (1 978) Progeny testing and selecting ltalian queens for brood area and honey pro1 003/79 duction Apidologie 9(2): 95-1 00 BRAUN, E

(1

942) One-year and two-year-old queens. A merican Bee

Journal 82i356-357 (1 922) The influence of the age of the queen on the honey crop. 8ee World 4(1):6-7.

BRUNNICH, K

CALE, G H; BANKER, R; POWERS, J (1978) Management for honey production. /n Dadant & Sons (ed) The hive and the honey bee Dadant & Sons; Hamilton, lllinois, USA; pp 355-412 CAVOJSKZ V (1 982) [Comparative pedormance of queen honey bees of various ages I Pol' nohospoddrstvo 28(8)i 7 37 -7 42.

1202/85 DIEHNELT, W (1 986) A queen's best age: when to requeen.Gleanings in Bee Culture 114(3): 143.

GENC, F; AKSOY A (1993) Some ofthe correlations between the colony development and honey production on the honeybee (Apis mellifera L.) colonies. Apracta 28:3341. LOUVEAUX, J (1967) Les probldmes pos6s par la g6n6tique et la s5lection de I'abeille. Annales de I' Abeille 10(4\:213-252. 74SLJ68 MOELLER, F E 0 958) Relation between egglaying capacity of queen

bees and populations and honey production of their

colonies Amerlcan Bee Journal 98fi0):

401-402.

177 /61

NOLAN, W J (1925\ The brood-rearing cycle of the honeybee. US Department Agriculture; Technical Bulletin No. 1349; 56 pp SOLLER, M; BAR-COHEN, R (1967) Some observations on the heri-

tability and genetic correlation between honey production and brood area in the honeybee. Journal of Apicultural 352/68

Research6(\:3743

SZABO, T l; LEFKOVITCH, L P (1 989) Effect of brood production and population size on honey production of honeybee colonies in Alberta, Canada. Apidologie 20(21: 157-163. 527 /9o

WOYKE, J (1984) Correlations and interactions between population, length of worker life and honey production by honeybees in a temperate region. Journal of Apicultural Research 23(3\: 1 48-1 56.