Pertanika 1(2), 70-81 (1978)

Observations on Growth and early Production of some Durian(Durio zibethinus Murr) Clones at Universiti Pertanian

Malaysia Orchard

OTHMAN YAACOB, MOHD. NOOR ISMAIL1 and AWALUDDIN HAJI TALIB2

Department of Soil Science, Faculty of Agriculture, Universiti Pertanian Malaysia

Key words: Durian growth, Early yield, Research needs.

RINGKASAN

Penyata mengenai tanaman durian diatas kawasan tanah bekas getah tua seluas 22 ekar adalah di-bentangkan bersama dengan rekod-rekod sukatan hujan, kadar membaja dan Iain-lain kawalan antali yangdibuat dalam kawasan itu semenjak 1969.

Kadar tumbohsaran semua jenis klon durian yang ditanam, keadaan membunga dan membuah sertadengan sebab-sebab kekurangan buah-buah bagi klon D2 dan D96 juga di bincangkan. Dengan adanya ke-adaan saperti itu, penyelidikan untuk mengatasi setengah daripada masalah masalah tertentu telah pun di-cadangkan untuk masa hadapan.

SUMMARY

The establishment of a 22 acre durian orchard on an oxisol soil formerly under old rubber is recordedoutlining the nature of the environment and the cultural practices adopted since 1969.

The growth pattern of all clones planted, early flowering and fruiting patterns are also discussed togetherwith possible causes of poor fruiting habits of D2 and D96. Some possible areas for research are suggested forfuture work based on these observations.

INTRODUCTION

The object of this paper is to provide back-ground information which may be required forany future detailed study on durian at Serdang.

The 22-acre site under study was at one timea part of the Air Hitam Forest Reserve. It wascleared for planting with rubber probably in the1940's by Serdang Estate which at that timeowned most of the land on which the UniversityFarm is now situated. The area was purchasedwith other land by the University in 1966; andin late 1968 it was mechanically cleared. Thetrees were felled and the trunks were sawn upfor wood and removed from the site. The remain-ing roots and stumps were collected into largeheaps and burnt after which the area was ploughedand rotovated three times. Remaining rootswere hand removed and burnt; and after a shortperiod of dry weather, planting holes measuring2' X 2' X 2' and spaced 40' x 40' apart were

prepared. This spacing allowed for 27 trees tobe planted per acre. In each planting hole about20 pounds of rotted cattle and poultry manurewere placed three weeks prior to planting.

In July 1969, during the wet season, therecommended durian clones were planted. Duringthe first four years, watering was carried outduring dry periods, or as and when necessary.

The general maintenance consisted of regularweeding and spraying against pests and diseases,carried out by the Farm Division and by thePlant Protection Department respectively.

DURIAN CLONES PLANTED ANDFERTILIZER PROGRAMME USED

Durian clones

The known clones planted were D2, D7,D8, D10, D24, D66, D84, D88, D96, and anunidentified clone designated as DR. The num-

1 Farm Director, Universiti Pertanian Malaysia.2 Senior Field Assistant, Universiti Pertanian Malaysia.

70

OTHMAN YAACOB, MOHD. NOOR ISMAIL AND AWALUDD1N HAJI TALIB

ber of trees planted for each clone and the per-centage composition of each clone in the area isgiven in Table 1. The actual distribution onthe ground is shown in Fig. 1. From the timeplanting began in 1969 until 1973, virtually allclones were replaced at various growth stages,mainly because of disease.

TABLE 1

Durian clones planted at the UniversitiPertanian Malaysia Orchard, Serdang.

Clone Number of treesplanted

Percentage oftotal stand

D2

D7

D8

D10

D24

D66

D84

D88

D96

DR

36

9

274

2

105

26

18

26

41

41

6.2

1.6

47.4

0.3

18.1

4.5

3.1

4.5

7.1

7.1

Total 578 100.0

Fertiliser programme

The fertiliser programme followed the'standard' practice recommended by Whitehead(1959). The rates of application over the yearsare shown in Table 2.

NATURE OF SOILS ANDTHE ENVIRONMENT

Topography and soils

The orchard can be divided into two broadsites based on the general topography of the areaand these are conveniently designated as theValley' and the (hiH\ A rise resulting in a slopeof more than 10° is designated the 'hill1 and aslope below this angle is designated the 'vallev'(Fig. 2).

The mechanical and chemical compositionof the two soil types found in the designated sitesare given in Table 3.

A portion of the valley is made up of collovialsoil while the hill is almost entirely of Malaccasoil with a varying depth of lateritic layers, the

nutrient content decreasing with depth. At theintermediate site, however, the nutrient contentis high in the upper layer 60 cm deep, wheremost of the feeding roots are located. In thevalley site the soil is relatively lighter in texturewith nutrient contents comparable to the hill site(Table 3). This is somewhat unexpected as soilson the lower sites normally have high nutrientcontents. It is probable that during the eightyear period, (1969-1978), the nutrients appliedmay have leached down the slope as suggestedby the high nutrient contents of soil at the inter-mediate site. Details of this possibility occurringare being studied as part of the current researchon durian.

Rainfall

The monthly and annual rainfall at Serdangfrom 1968 to 1977 are given in Table 4.

The average rainfall for the 10 year period(1969-1977) was 2131 mm although the annualrainfall for 1974 and 1975 was below average.The two dry years adversely affected the generalyield of durian throughout the country (Anon1976). *

AGRONOMIC OBSERVATIONS

Growth pattern

There are several parameters by which growthcan be measured. In this study, growth wasmeasured by taking the height of the tree fromthe base of the trunk at ground level to the topof the canopy, and the total spread of the canopyfrom left to right. A specially constructed lightalluminium frame was used for this purpose(Plate 1).

The growth shape of durian trees appearedto differ slightly among clones. The averagerange of height of trees varied from 5.5 for D88to 7.8 m for the unidentified (DR) clone. Thespread of the canopy was narrow in D88, being1.8 to 1.9 m, and wider in D24, from 3.1 to 3.0 m.The average height of the remainder of the clonesranged between 5.8 to 7.5 m for height; and 2.3to 2.4 or 2.9 to 2.8 for canopy spread (Table 5).At Serdang the growth shape characteristics ofeach clone remain constant (Plates 2a - 2e) butthese characteristics vary slightly in other partsof the country because of different environmentalconditions. However, no information on thisvariable characteristic is available at the present.

Flowering pattern

First flowering of certain clones was observedin September 1974. Flowering from all trees

71

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*—• • {

i

<X̂

R L i E A R C H

( • L O T

1 • . " \ \

\

V

• •Trac

• • • • • • .J o ? c Z:a Co ^5 " ? .7.2 :

tor -hath

. -•* ^ ^ [.^, ^d u 0 38 Od D8 D3 ^ 8 8 D84 D66 /9 6

•

D8

a70

o

>0m>

r

7ODC

O

o

DC2

nrOm

Fig. 1 Distribution of durian clones planted on the Universiti Pertanian orchard.

OTHMAN YAACOB, MOHD. NOOR ISMAIL AND AWALUDDIN HAJI TALIB

TABLE 2

Fertiliser programme and rate (oz/tree) for durian at the Universiti Pertanian Malaysia: 1969-1978.

Year Season/monthof application

Fertiliser type*/grade

Amount/rate(oz/tree)

1969

1970

1971

1972

1973

1974

1975

1976

1977

1978

JulySeptemberDecember

JanuaryMarchJuneJulySeptemberDecember

JanuaryMarchJuneSeptemberDecember

JanuaryJuneDecember

AprilSeptember

AprilSeptemberDecember

AprilSeptemberDecember

September

JulyOctober

CCM 12CCM 12CCM 12

Nitro 26 %NCCM 24CCM 22Nitro 26%NCCM 22CCM 22

Nitro 26°/oNCCM 44CCM 22CQM 22CCM 66

Nitro 26%NCCM 66CCM 25

CCM 22CCM 22

CCM 25CCM 25CCM 25

CCM 25CCM 25CCM 25

CCM 44

Muriate of PotashCIRP

February CCM 44

4.04.04.0

4.010.012.04.0

14.016.0

8.020.022.024.024.0

8.032.040.0

80.080.0

96.096.096.0

112.0112.0112.0

80.00

80.0080.00

88.00

* The range of compound formulations in

Fertiliser compound no.

CCM 12

CCM 22

CCM 24

CCM 25

CCM 44

CCM 66

Nitro-26

Christmas Is. (CIRP) Rock Phosphatem

Muriate of Potash

the ferilisers

% N

11

10

11

14

12

14

25

-

used is given

% P2O5

18

16

18

13

6

14

-

—

below:

% K2O

4

9

11

9

22

14

-

46

% MgO

3

2£

4

2*

3

-

-

—

Total nutrients

36

37£

39

38J

43

42

-

—

73

Collovium, good drainage,laterite > 50cm

°o°o0

Malacca soil - laterite >50cm- laterite 25-50cm- laterite 0-25cm

Pond/stream

- Building

OoHX

Dm

7

OD

n

DC

nOm

Fig. 2 Soil map of the orchard.

Mechanical

Site Depth (cm)

'Hill' 0-30

30-60

60-90

90-120

'Intermediate* 0-30

30-60

'Valley' 0-30

30-60

60-90

90-120

120-150

and

CS

11

10

16

19

12

15

21

19

20

20

20

chemical composition of soils at

Mechanical

FS

28

23

24

22

24

21

39

36

32

30

33

S

18

21

17

19

10

10

7

7

6

7

6

analysis

C

43

46

43

40

54

54

33

38

42

43

41

TABLE :

three sites located on the

pH

4,5

4.3

4.4

4.6

5.1

5.2

5.0

4.9

5.0

5.1

5.3

P

10.6

7.6

2.2

0.3

4.0

23.1

3.1

1.3

0.5

0.4

0.2

22-acre orchard at the

NutrientsAvailable (ppm)

K

47.0

32.0

33.0

38.0

142.0

105.0

36.0

34.0

27.0

24.0

16.0

Ca

6.8

6.4

4.0

6.4

31.4

20.4

9.6

4.6

6.0

5.2

6.2

University Orchard

Mg

28.4

24.8

21.6

20.8

49.6

40.6

31.2

23.4

22.0

19.8

20.8

N

0.15

0.23

0.12

0.11

0.24

0.19

0.15

0.15

0.12

0.12

0.12

Total (%)

C

1.4

1.0

0.7

0.

52.1

1.4

1.1

0.9

0.7

0.5

0.4

OM

2.6

1.9

1.3

1.0

3.9

2.7

2.1

1.7

1.4

0.9

0.8

OT

HM

AN

>

CO

B, M

O

pZQo73

IAIL A

ND

i

s>

rCDDN

HA

JIT

AL

IB

GROWTH AND EARLY PRODUCTION OF DURIAN CLONES

TABLE 4

The monthly and annual rainfall: (mm) at Serdang: 1968-1977.

Year

1968

1969

1970

1971

1972

1973

1974

1975

1976

1977

10 yr. average

J

114

98

200

422

56

172

102

95

-

283

171

F

161

129

60

124

186

212

150

126

112

113

137

M

241

304

277

244

135

211

151

156

341

106

217

A

272

166

163

316

363

555

284

183

382

176

286

M

234

-

283

38

169

423

183

48

130

104

179

J J(mm)

167

219

112

80

145

30

9

62

203

195

122

169

106

117

180

55

116

83

166

58

81

113

A

137

106

145

352

99

177

10

124

214

170

153

s

114

133

247

92

141

191

90

18

170

160

137

O

353

386

130

109

266

282

40

98

371

372

241

N

278

289

279

144

263

232

20

166

287

245

220

D

171

234

177

244

172

230

152

119

247

165

191

Total

2411

2170

2190

2345

2050

2831

1274

1361

2525

2170

2131

TABLE 5

Growth pattern of durian clones at the Universiti Pertanian Malaysia Orchard

Clone

D 2

D 8

D 24

D 66

D 88

D 96

DR

No. of treesmeasured

13

74

20

10

9

11

15

Height

5.2-7.0

3.7-6.3

6.3-8.3

6.0-8.9

4.1-6.6

6.0-7.8

6.3-8.4

Range forCanopy

Left Right

1.8-3.3

1.1-4.0

2.7-4.1

2.2-2.8

1.4-2.3

1.9-3.0

2.5-3.3

1.9-3.1

1.5-4.0

2.7-4.1

3.0-2.8

1.3 -2.4

1.8-3.1

2.6-3.0

Height

6.1

5.8

7.5

7.3

5.5

6.5

7.8

Mean

Left

3.8

2.9

3.1

2.5

1.9

2.3

2.9

Canopy* Right

2.7

2,8

3.0

2.4

1.8

2.4

2.8

Other clones were not measured as they formed only a small percentage of the total (Table 1).

beginning in February 1977 was subsequentlyrecorded and expressed as a percentage of thetotal number of trees for each clone. Numbersof fruits obtained were also recorded (Table 6).

It is clear that under the environmentalconditions recorded and the cultural and manualpractices adopted at Serdang, virtually all clonesderived from budded planting materials floweredfive years after planting. Except for D2 and D88,the number of clones flowering later than fiveyears of age was less than fifteen per cent for thefirst four seasons in 1974 and 1975 (Table 6).

In 1975, the year following the drought when theannual rainfall recorded for 1974 and 1975 wasbelow the ten years average, three floweringseasons were recorded. The first was in February,the second in May and the third in November.Except for D88, all other clones showed a lowpercentage of trees flowering in the Februaryfruit season. Clone D2, for example, showed16% of trees flowering as compared to the 23%recorded for D88 in the May season. In theNovember season all clones except D88 showeda low percentage of trees flowering with no fruitsbeing recorded at all. Premature dropping and

76

OTHMAN YAACOB. MOHD. NOOR ISMAIL AND AWALUDDIN HAJI TALIB

Plate 1. Technique for measuring the height and canopy spread of a mature durian tree.

77

GROWTH AND EARLY PRODUCTION OF DURIAN CLONES

a

Plate^2a-2e Clonal characteristics of some durian trees at the Universiti Pertanian Malaysia Orchard.

78

OTHMAN YAACOB, MOHD- NOOR ISMAIL AND AWALUDDIN HAJl TALTB

theft accounted for the poor fruit recordings.In the following dry year (annual rainfall for 1975was 1361 mm), all clones snowed a high percentageof trees flowering in February and July of 1976and some fruits were recorded (Table 6).

Observations and recordings indicated thatthe dry years of 1974 and 1975 stimulated theproduction of a large number of fruits throughoutthe country. It has been suggested that durian

It is possible that during a peak period, the deve-loping fruits use up a great deal of stored nutrients;and before another large quantity of fruits canbe produced, time is needed to replace the storedmaterials; this results in high yields occurringin alternate years. The preliminary data on theflowering pattern of the clones appear to supportthis contention, although it is a too early as yetto confirm this theory.

TABLE 6

Relationship between the percentage flowered and number of fruits harvested.

Yearand

season D2 D8

°o Flowered

D24 D66 D88 D96 D2 D8

No. of fruits

D24 D66 D84 D88 D96

1974 Sept

1975 Feb)

1975 May)

1975 Nov)

1976 Feb)

1976 Jul)

1977 Feb)

1977 Jul)

22

-

16

-

64

-

61

-

0.4

1

1

0.5

25

3

25

-

7

10

4

4

39

2

19

-

8

11

-

8

-

63

42

-

30

23

23

3

50

3

7

-

8

14

-

9

73

4

9

-

—

-

-

-

72

67

37

35

—

-

-

-

-

-

57

58

—

-

-

-

-

30

58

27

—

-

-

-

-

-

-

10

— —

-

-

-

-

81

98

83

trees bear fruit biannually; the 1975/1976 seasonswere peak years for the crop (Anon., 1976). Thepeak periods may have coincided with the dryweather as was the case for 1975/1976 seasons.

Clones D2 and D96 did not retain fruits atall under Serdang conditions, although they didwell during the early years (1948-1968) at theFederal Experimental Station Serdang (Lee and

79

GROWTH AND EARLY PRODUCTION OF DURIAN CLONES

Loh, 1966). Fruit drop is also common amongvarious clones. Generally, fruit of the size ofgolf balls dropped prematurely suggesting thatsome kind of physiological disorder may havebeen prevalent to cause premature fruit drop.During the two seasons when flowers and fruityields were recorded, only D88, which bearslarge-size fruits weighing between 2.4-3.6 kg,indicated good fruit numbers. The other clonesdid not give high yields (Table 6). The pheno-menon of flower and fruit drop at various stagesis being investigated in conjunction with verypoor fruiting habits of clones D2 and D96.

RESEARCH CONSIDERATIONS

Our observations of the performance ofdurian clones in the Serdang environment suggestthat it would be worthwhile undertaking similarstudies of other fruit trees grown in the Univer-sity Farm. Such studies should incorporate:

Clonal characteristics and crown shape

Although in this study the characteristics ofall clones were measured and pictorally recorded(Plates 2a - 2e), it would be desirable to extendthe research to incorporate a study of the geneticsources of the clones and a detailed morphologicalstudy of their differences. Furthermore, researchshould also include a comparative study of theperformance of the same clones in differentenvironments. A comparison of crown shape bythe techniques outlined earlier in this paper mayrequire further verification and possible modifi-cation for wider use.

Furthermore, there is a need for charac-terisation of individual clones giving details onfruit and vegetative description, supported bypictorial illustration. Other descriptions usefulfor identification would include enzyme essays,etc.

Fertiliser requirements

The basic fertilizer requirements of durian,originally a jungle tree, need to be determinedif optimum results are to be obtained. Such astudy should be extended to include the require-ments of other fruit trees. Although in the 22-acre orchard a general fertilizer programmeexists (Table 2), a portion of the orchard has beenfenced off for detailed experimental research(Fig. 1).

The type and amount of fertilizers exert astrong influence on the production of fruits.Information on fertiliser effect on durians islimited. Future research should focus on soil

fertility, fertilizer recommendation, suitablemethods of fertilizer placement, time of appli-cation, relationship between fertilizer amount andwater regimes on yield and more efficient meansof fertilizer application.

Flower and fruit drop

Despite the high percentage recorded oftrees having flowered (Table 6), the fruit retainingability of almost all clones, particularly D2 andD96, is generally poor. A close look at the plant-ing pattern of durian clones (Figure 1) maysuggest certain lines of investigation. For example,a large tract of D8, clustered in one area mayinduce self-incompatibly within the clone and adetailed study on the pollen viability is required.Over and above these, the conspicious absenceof arboreal life, so characteristic of a 'dusun' atflowering times, may be a limiting factor in thepollination of durian flowers. For example, batswhich pollinate the flowers are virtually absenteven at midnight. Bees, another group of efficientpollinators, are also absent as there are no alter-native hosts during the durian off-seasons. Inthe absence of such natural pollinating agents,it may be desirable to carry out hand-pollinationsimilar to that done with oil palm using a fewselected trees of all clones; but the economicaspects of adopting this practice need furtherstudy.

Weeding

Under the natural 'dusun' ecosystem, weed-ing is not carried out except during the fruitingseason when the base around each tree is clearedto facilitate easy collection of fruits. However,under an orchard system, weeding with imple-ments driven by heavy tractors is carried outregularly, eventually causing heavy compactionof the top 15 cm soil where the most active feedingroot system is located (Othman Yaacob et al.y1977). These procedures affect the surface soilas well as the entire microclimate under eachtree.

Accordingly, a part of this 22 acre was fencedand used as a research plot (Figure 1) wherebasic quantitive recordings were carried out.Some areas of investigation using this fencedarea include: (a) reduction of fertilizer appli-cation; (b) reduction of weeding.

The effects of these practices on the relativehumidity and air temperature in weeded andunweeded plots, with and without fertilizer, arebeing monitored. As the trees of all clones arenow fully developed at seven years of age, andtheir vegetative growth is satisfactory, fertilizersmay not be needed in large quantities. Further-

80

OTHMAN YAACOB. MOHD. NOOR ISMAIL AND AWALUDDIN HAJI TALIB

more, as the amount required for fruit productionis relatively small (Ng and Thamboo, 1967) andpruning is minimal, any fertilizer applied wouldonly be for 'fruiting' and not for 'growth'. Theeffect of fertilizer on young durian trees with andwithout weeding to approximate 'natural' con-ditions commonly found in the 'dusun' wouldbe a part of this programme. The effects of thesecombinations of treatment on the floweringpercentage and fruit set are being studied as partof the basic research on durian at the UniversityFarm.

ACKNOWLEDGEMENTS

We would like to thank all field and labora-tory personnel in the Soil Science Departmentfor their technical assistance during the courseof this study and Prof. I.C. Enoch for his valuablecomments in the preparation of this paper.

REFERENCES

ANON., (1976): "A Feast of Durian - Thanks to theWeather/' Malay Mail, 13th July, 1976.

LEE, C.S. and LOH, C-L. (1966): Durian varietal trial.Information paper No. 52 Dept. Conf. Min. Agric.Co-op. Kuala Lumpur, (cyclostyled memograph).

NG, S.K. and THAMBOO, S. (1967): Nutrient removalstudies on Malaysian fruits: Durian and rambutan.Malay. Agric. J. 46: 164-183.

OTHMAN YAACOB, KHANIF YUSOF and MOKHTARUDDINMANAN (1977): Rainfall pattern and food- cropproduction on old-rubber soils at Serdang. In"Proceedings on Food-Agriculture Malaysia 2000".(Ed) H.F. Chin, I.C Enoch and Wan "MohamadOthman pp. 101-111. Faculty of Agriculture,Universiti Pertanian Malaysia.

WHITEHEAD, C. (1958): The establishment and main-tenance of fruit trees. Malay. Agric. J. 42: 163-184.

(Received 19 July 1978)

81