Study of the different irrigation and fertilization levels effects on fruit set and yield of tissue cultured Barhee date palms

International Journal of Agriculture and Crop Sciences. Available online at www.ijagcs.com IJACS/2012/4-22/1666-1671 ISSN 2227-670X ©2012 IJACS Journa...
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International Journal of Agriculture and Crop Sciences. Available online at www.ijagcs.com IJACS/2012/4-22/1666-1671 ISSN 2227-670X ©2012 IJACS Journal

Study of the different irrigation and fertilization levels effects on fruit set and yield of tissue cultured Barhee date palms Abdol Amir Rahnama, Madjid Alihouri Abdol and Hamid Mohebi IRAN, Ahwaz, Date palm and tropical fruits research institute, P. O. Box: 61355-16. Corresponding Author email: [email protected] ABSTRACT: It is probably that to dominance of vegetative to reproductive growth can delay fruit set of date palm seedling (CV. Barhee) in early fruiting. Because with increasing age and growth balance, fruit set will be improved. This experiment with aim of increasing fruit set in the early fruiting was carried out in randomized complete block design with three replications, in split plot method with three irrigation intervals in main plots, and three fertilization levels in subplots during 2008-11. The irrigation intervals were equal 7 (control), 14 and 21 days from pollination stage to harvest stage and the fertilization levels were control (research recommendation), 30% less than control and 30% more than control. The results showed there was not significant effect of irrigation treatments on fruit set and yield, but fertilization treatments had significant effects. The interaction effects were significant on all characteristics. The highest fruit weight, fruit diameter and fruit volume was obtained in 7 days irrigation interval and control fertilization level. The highest bunch weight and yield was obtained in 7 days irrigation interval and 30% less than control fertilization level, that may be resulted from vegetative limiting and reproductive stimulating. Key words: Irrigation, Fertilizer, Fruit set, Yield, Date palm, Abnormality. INTRODUCTION Date palm (Phoeniu dactylifera L.) is one of the important and strategic fruits in Iran. Based on FAO reports (FAO, 2010) date palm area harvested and annually date palm production in Iran are 156618 ha and 1023130 tons, respectively. Among different date palm cultivars, Barhee date palm is one of the most commercial and popular date cultivars in the world. Khouzestan province in southwest of Iran is one of the main producing areas of this cultivar. The traditional method of date palm propagation is by off shoots. However this method presents many disadvantages. Offshoot is produced in limited number, the survival rate of offshoots is low, with high chance of spreading date palm diseases and pets. This technique is difficult and laborious. The most recent method for date palm propagation is tissue culture which presents many advantages such as the propagation of healthy selected female cultivars, production of genetically uniform plants and economic affordability when large production is needed. However one of the major weaknesses of mass tissue culture propagation techniques is the appearance of undesired off type plants caused by somaclonal variation (Zaid and Al-Kabbi, 2003; Al-Mazroui et al., 2007.). Such variations can be epigenetic or genetic. Morphological characteristics and fruit quantitative and qualitative characteristics of Barhee date palm propagated through tissue culture and offshoot were compared from 1999 to 2002 on a date palm germplasm collection in Iran (Hajian, 2007). The results showed significant differences in only 16 of the 97 characteristics of two groups. There were no important morphological changes related to genetic abnormalities in the trees by tissue culture technique. Such abnormalities were recorded in many orchards around the world, including Saudi Arabia, South Africa, Namibia and UAE (Al–Ghamdi, 1993; Mccubbin et al., 2000; Djerbi, 2000; Cohen et al., 2004). Sensitivity differences in the occurrence of abnormalities among date palm cultivars have been observed (Zaid and AlKabbi, 2003). They reported that Barhee cultivar was more susceptible to pollination failure and abnormal fruiting than Medjool, Khalas and Deglet Nour. They concluded that the frequency of abnormalities was generally about 5% with the exception of pollination failure in Barhee cultivar. Such incidence of abnormalities was acceptable to date palm growers. This phenomenon was reported by Al–Wassel (2000) on Barhee, Khalass, Sukkavi and Ajoua with fertilization failure between 60-86%. Tissue cultured Barhee date palm showed a high level of genetic variation when compared with offshoot derived and seedling derived male and

Intl J Agri Crop Sci. Vol., 4 (22), 1666-1671, 2012

female Barhee date palm (Al–Khalifah and Askari, 2007). Award (2007) studied effect of five date palm pollinators with five different pollination densities of eight year tissue culture derived Nabt Saif palm trees. Generally neither the pollinators nor the pollination density resulted in a satisfactory level of fruit set. Also there were no significant differences between the different pollination densities on fruit set and fruit quality. Ruther and Crawford (1951) were evaluated irrigation deficit effect on Deglet Nour date palm in this experiment dry plots were irrigated very sparingly during the period June-October. The soil moisture was maintained at less than 40% of total storing capacity. The results showed with holding moisture during developing and ripening period markedly reduces the percentage of high grade fruit, as well as reducing fruit yield about 17.5% Sharples and Hilgman (1951) showed that Makhtoom date palm vegetative growth reduced significantly with 3-4 week compared 10-14 days irrigation interval. Furr and Armstrong (1955) studied effect of irrigation interval on 18 year old Khadrawy date palms. The treatments consisted of variations in time interval between applications of water as follows: 2, 4, 8 and 16 weeks. The results showed yield and leaf growth rate was not significantly reduced by water shortage, though there was a slight progressive decrease in leaf growth rate from the 2 weeds to the 8 weeks treatments. Allowing soil moisture in the principal root zone of the 16 weeks treatment to remain for several weeks in the witting range resulted in significant reductions in leaf growth rate and fresh weight of fruit and caused a delay in emergence of inflorescences in the following spring. The effect of water stress was investigated during flowering and fruit set stages of Barhee date palm (Alihouri, 2011). This study was carried out with five treatments of irrigation: namely 50, 100, 150, and 200 mm with irrigation depth equal to 100% net irrigation requirement and 200 mm with irrigation depth equal to 50% net irrigation requirement after reoperation from class A pan. The results showed that effect of irrigation treatments on fruit drop, fruit and stone weight, fruit diameter and yield were significant. The highest fruit weight, diameter and yield were obtained with irrigation after 50 mm evaporation from the class A pan. Uptake of nitrogen by date palm trees did not exceed 60% of that added in fast release N fertilizer (fatehy, 1989). Using slow release fertilizer was proved to be very favourable in improving growth, nutritional status of the trees, fruit set, yield and fruit quality date palms. Bamiftah (2000) recommend 2 or 3 kg of potassium sulfate/palm/year for increasing the vegetative growth, yield and fruit quality of date palms. Morsi (2009) reported organic fertilization combined with inorganic nitrogen fertilizer was very useful in improving growth nutritional status and increasing yield and fruit quality of Seewy date palm. The highest dry matter content was observed in Khalas and Khassab cultivars of date palm when mineral fertilizers (urea, triple super phosphate and potassium sulfate) were supplemented with organic peat and micronutrients (Al-Kharusi et al., 2009). The nutrient spray applications can also cause yield and fruit size improving, without thinning agents requirements (Khayyat et al., 2007). The objective of this study is to investigate the effect of irrigation water and nutrition different levels on increasing fruit set and fruit yield. MATERIAL AND METHODS This research was carried out in Barhee tissue culture date palm garden of date palm and tropical fruit research institute of Iran during 2 years 2008-2009. These trees were showed abnormality in fertility and fruit set during 3 years reproductively. The experimental was Randomized Complete Blocks Design (RCDB) whit three replication. Three irrigation intervals as 7 days interval (control), 14 and 21 days interval, were located in main plots. Total water volume needed for each irrigation treatment was compete based on follow equation (Allen et al, 1998). ET0=KP. EPan ETc= Kc.ET0 Tc=(Etc – Re)[Ps + 0.15(1-Ps)] Ig =Tc . E-1 G = Ig . Sp. Sr ET0= Reference crop evapotranspiration [mm.* d-1], Re= Effective rainfall (mm.) KP= Pan coefficient, EPan= Evaporation from pan, Etc= Crop evapotranspiration(mm.) Kc= Crop coefficient(dimensionless), Etc= Crop evapotranspiration [mm d-1] Re= Effective rainfall(mm), Ps= Plant shadow(canopy), Ig= Gross irrigation requirement mm day-1 requirment mm day-1 Tc= Crop transpiration, E= Efficiency irrigation, G= Gross irrigation volume Sp= Space between each plant, Sr= Space between each row Three fertilization levels as complete fertilization(1000 gr. N, 700 gr. P2O5, 1000 gr. K2O, 100 gr. FeSO4, 100 gr. ZnSO4, 50 gr. CuSO4, and 50 gr. MnSO4 as fertilization control treatment ), %30 fertilization less and more than control were located in sub plots based on soil sampling test(table1) .

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Table 1 . soil physic and chemical for experimental site. Soil Dept (cm) 0-30 30 – 60 60 – 90

EC -1 (ds. m )

pH

O.C (%)

P ava. (ppm)

K ava. (ppm)

Cu ava. (ppm)

Mn ava. (ppm)

Fe (ppm)

Zn ava. (ppm)

5.8 4.0 4.8

7.8 7.9 7.8

0.73 0.47 0.33

22 16 24

270 141 150

1.26 1.2 1.07

5.2 4.4 5.0

7.1 4.2 4.32

0.42 0.22 0.2

Table 2 . chemical analysis for Irrigation water +

2+

2+

2-

-

3-

2-

Na -1 (meq. lit )

Mg -1 (meq. lit )

Ca -1 (meq. lit )

SO4 -1 (meq. lit )

Cl -1 (meq. lit )

HCO -1 (meq. lit )

CO3 -1 (meq. lit )

pH

EC -1 (ds. m )

(SAR)

9.9

12.0

4.0

4.0

7.6

3.4

3.0

8.0

3.5

2.3

The other practice so as pollination, pest, disease, and weed control, offshoots plants separation and leaf to bunch ratio were same for each treatment. Fruit set fertility percent, dropped fruit percent, each date palm tree fruit yield, and different fruit characteristic were compete every years, raw data were analysis by MSTATC software and different means compare with Duncan’s multiple Range Test. RESULTS Fruit set combined analysis of variance showed that irrigation interval treatments had no significant effects on fertile and no fertile fruit percent rate to initiation and total fruit and dropped fruit percent (Table 3). Average compare of traits fruit set showed that no significant effects by Duncan’s Multiple Range Test (Table 4), but Fertilization levels treatments had significant effects on fertile fruit set percent. The highest fertile fruit set percent rate to initiation and total fruit and dropped fruit percent were 34.9 and 74.8, respectively and the lowest were 11.9 and 25.4%, observed in treatment of 30% fertilization lesser than control. There were no significant differences between the other treatments (table 4). Analysis of variance showed that interaction of irrigation and fertilization have significant differences on the ratio of fertilized fruits to initiation, the ratio of unfertilized fruits to initiation, the ratio of fertilized fruits to total and the ratio of unfertilized fruits to total fruits. Comparison of means by Duncan test showed that the maximum ratio of fertilized fruits to initiation and total were 42.6 and 81.1% and the lowest were 9.2 and 19.2%, respectively. The minimum percent of dropped fruits (48.5%) observed in the treatment of 7 days interval irrigation and fertilization 30% lesser than control (table5). Table 3. combined analysis of variance for different traits of fruit set S.O.V

d.f. 2

% fertile fruit / initi. 1423.1 **

% unfertile fruit/initi. 4918.8 **

% Dropped fruit 1165.6 **

% unfertile fruit /total 15633.3 **

% Fertile fruity/total 15211.1 **

Year (Y) Replication (R)

6

132.7 n.s

22.5 n.s

72.6 n.s

157.5 n.s

151.3 n.s

Irrigation ( I )

2

67.6 n.s

13.5 n.s

34.3 n.s

77.8 n.s

69.3 n.s

Y*I

4

18.8 n.s

13.6 n.s

17.1 n.s

49.2 n.s

46.2 n.s

Error a

12

123.8

104.9

158.8

170.1

169.9

2

272.9 *

338.9 **

3.9 n.s

581.0 **

569.0 **

Y*F

4

264.8 *

615.2 **

261.8 *

1562.4 **

1560.2 **

I*F

4

196.3 *

110.5 *

130.2 n.s

271.4 *

275.0 *

8

32.9 n.s

79.8 n.s

88.4 n.s

177.9 n.s

169.4 n.s

Error b

36

74.4

37.6

94.2

92.0

90.3

C . V. ( % )

-

27.4

38.5

18.3

13.7

31.1

Fertilization ( F)

Y*I*F

Table 4. Fertilization levels mean comparison of fruit set factor Treatments F

-%30 C F +%30

% Fertile fruity/initi. 34.9 a 28.7 b 30.7 ab

% unfertile fruit / initi. 11.9 b 18.9 a 16.9 a

% Dropped fruit 53.3 a 52.7 a 52.6 a

% fertile fruit / total 74.8 a 66.0 b 68.0 b

% unfertile fruit/total 25.4 b 34.2 a 32.1 a

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Means , in each colum , followed by at least one letter in common are not significantly different at the 5% probability levelusing Dancan.s multiple Rage Test. C= Fertilization control -%30 = Less than control +%30= More than control Table 5. Irrigation intervals and fertilization levels interaction of fruit set factor Treatments I 7 * F - % 30 FC F + % 30

% Fertile fruity/initi. 42.6 a 29.4 b 27.8 b

% unfertile fruit / initi. 9.2 d 17.1 abc 19.9 a

% Dropped fruit 48.5 b 53.9 ab 52.5 ab

% fertile fruit / total 81.1 a 67.4 bc 63.7 c

% unfertile fruit/total 19.2 c 32.8 ab 36.6 a

I 14 * F - % 30 FC F + % 30

30.2 b 28.5 b 32.1 b

11.6 cd 20.4 a 18.1 ab

58.2 a 51.3 ab 50.0 ab

73.6 ab 63.3 c 66.1 bc

26.5 bc 37.0 a 33.8 ab

32.0 b 28.2 b 32.61 b

15.1 abc 19.2 a 12.6 bcd

53.2 ab 52.9 ab 55.4 ab

69.9 bc 67.3 bc 74.2 ab

30.5 ab 32.9 ab 25.9 bc

I 21 * F - % 30 FC F + % 30

Means , in each Colum , followed by at least one letter in common are not significantly different at the 5% probability levelusing Duncan’s multiple Rage Test.

I = irrigation intervals,

N = fertilization levels -%30 = less than control +%30 = more than control

C = Control

Analysis of variance showed that interval irrigation don't have significant effects on weight, length, diameter and volume of fruit, bunch weight and yield (table 6). Comparison of means the mentioned traits by Duncan Test showed that all of treatments replaced in one class. The highest yield (40.1 kg/palm) and bunch weight (5.6 kg) observed in 7 days interval irrigation treatment. Analysis of variance showed that fertilization treatments have significant effects bunch weight and yield. The maximum fruit weight (11.4 g) observed in fertilization based on 30% more than control and minimum fruit weight (10.7 g) observed in fertilization based on 30% lesser than control. The maximum yield (40.0 kg/palm) and bunch weight (5.8 kg) observed in fertilization based on 30% lesser than control and minimum bunch weight (4.7 kg) and yield (29.9 kg/palm) observed in control treatment (table7). Analysis of variance showed that interaction of irrigation and fertilization have significant differences on the all of fruits traits expect bunch weight that it was no significant. Comparison of means by Duncan Test showed that the maximum weight , diameter and volume of fruits observed in 7 days interval irrigation treatment with control fertilization and the maximum of yield and bunch weight observed in 7 days interval irrigation with fertilization 30% lesser than control treatment (table 8). Table 6. combined analysis of variance for different traits of fruit characteristic S.O.V

d.f.

Fruit Weight

Year (Y)

2

48.92

Replication (R)

6

Irrigation ( I )

Fruit length

Fruit diameter

Fruit volume

Fruit yield

**

0.680

**

0.182

**

23.46

1.59

n.s

0.036

n.s

0.007

n.s

1.50

2

0.76

n.s

0.010

n.s

0.008

n.s

Y*I

4

0.14

n.s

0.010

n.s

0.009

n.s

Error a

12

1.88

Fertilization ( F )

2

2.83

n.s

0.008

n.s

0.037

n.s

2.06

n.s

8.12

*

743.4

Y*F

4

1.17

n.s

0.027

*

0.013

n.s

1.71

n.s

0.55

n.s

73.3

I*F

4

3.63

*

0.038

**

0.041

*

4.43

**

3.84

n.s

301.4

*

Y*I*F

8

0.49

n.s

0.007

n.s

0.007

n.s

0.55

n.s

1.43

n.s

108.8

n.s

Error b

36

1.15

0.009

0.011

1.11

2.46

113.2

C . V. ( % )

-

9.6

2.9

4.2

9.5

29.8

29.7

0.027

0.020

**

Bunch weight 4.41

n.s

244.8

n.s

2.88

n.s

94.9

0.92

n.s

2.32

n.s

398.9

n.s

0.14

n.s

0.12

n.s

121.8

n.s

2.44

3.21

n.s

n.s

196.0 **

n.s

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Table 7. Fertilization levels mean comparison of fruit characteristic Treatments

F

Fruit Weight (g) b 10.7 ab 11.1 a 11.4

-%30 C

F

+%30

Fruit length (cm)

Fruit diameter (cm) a 2.5 a 2.5 a 2.5

a

3.2 a 3.3 a 3.2

Fruit volume 3 (cm ) a

10.8 a 11.1 a 11.3

Bunch weight (kg) a

5.8 b 4.7 ab 5.3

Fruit yield (kg/tree) a

40.0 b 29.9 ab 37.3

Means , in each colum , followed by at least one letter in common are not significantly different at the 5% probability levelusing Duncan’s multiple Rage Test.

C= Fertilization control

-%30 = Less than control +%30= More than control

Table 8 . Irrigation intervals and fertilization levels interaction of fruit characteristic Treatment

I 7 * F - % 30 FC F + % 30

Fruit Weight (g) c 10.1 a 11.8 ab 11.6

I 14 * F - % 30 FC F + % 30

10.8 abc 10.9 abc 10.9

I 21 * F - % 30 FC F + % 30

11.3 bc 10.6 ab 11.6

Fruit length (cm)

Fruit diameter (cm)

c

2.4 a 2.6 a 2.6

abc

2.5 abc 2.5 abc 2.5

ab

2.5 bc 2.5 ab 2.5

3.2 a 3.3 abc 3.2

abc

3.2 ab 3.3 c 3.2

ab

3.3 bc 3.2 a 3.3

Fruit volume 3 (cm )

Bunch weight (kg)

Fruit yield (kg/tree)

c

10.0 a 11.7 ab 11.6

d

6.3 bc 4.9 abc 5.6

a

47.4 c 30.2 ab 42.7

a

abc

10.8 ad 11.0 bcd 10.7

ad

5.1 abc 4.3 abc 5.1

abc

42.1 c 26.1 bc 33.6

ab

11.4 cd 10.6 abc 11.5

abc

6.0 c 5.0 bc 5.2

a

30.4 bc 33.2 bc 35.7

ab

c

Means , in each colum , followed by at least one letter in common are not significantly different at the 5% probability levelusing Duncan’s multiple Rage Test.

I = irrigation intervals, N = fertilization levels +%30 = more than control

-%30 = less than control

C = Control

DISCUSSION The establishment of date palm plants which propagated from tissue culture in cause for its widespread roots are better rather than offshoots plant. Also this plant for extra vegetative growth and competition whit reproductive growth to decrease fertility percent and normal fruit. To change in irrigation intervals and fertilization levels in cause to limit vegetative growth or to provide supplementary for trees, to reduce competition and improved fruit set condition( hajian, 2006; Alihouri, 2008). The results showed irrigations intervals had no significant effects on fruit set, but to change fertilization levels %30 less than control, in reason for its positive effects, produced highest fertile fruit set. In other word, to decrease fertilization level, to limit vegetative growth rather than reproductive growth. Litterateur review showed, increase in some elements, to make disorganized plant metabolism, and prevent respiration action(Vines and Wedding, 1960). So based on this results in order to increase Barhee tissue culture date palm fruit fertility percent, that have reproductive abnormality, recommended to limit fertilization level %30 percent less than control with 7 days irrigation interval. But this is nessecery to reminded that complete fertilization with considering plant condition recommended for normal plants. Finally this results and other research showed that tissue culture plant fruit set abnormality needed more research(Al-Kaabi, et al 2007; AlWasel, 2001; Awad, 2007 and Djerbi, 2000). REFERENCES Al–Ghamdi AS. 1993. True o type date palm (Phoenix dactylifera L.) produced through tissue culture techniques. 4- Fruit physical th properties. 3 Symposium on Date Palm. King Faisal University, Al-Hassa, Saudi Arabia, 17-20 Jun, 1:9-54. Alihouri M. 2008. Effects of water stress on fruit drop and yield of date palm (Phoenix dactylifera L.). J. of Pajouhesh and Sazandegi,79:178-185 Al-Khalifah NS, Askari E. 2007. Early detection of genetic variation in date palms propagated from tissue culture and offshoots by DNA fingerprinting. III International Conference on Date Palm. Acta Hort. 736:105-112. Al-Kharusi LM, Elmardi MO, Ali A, Al-Said FA, Abdelbasit KM, Al-Rawahy S. 2009. Effect of mineral and organic fertilizers on the chemical characteristics and quality of date fruits. International Journal of Agriculture & Biology 3:290-296. Al-Mazroui H, Zaid A, Bouhouche N. 2007. Morphological abnormalities in tissue culture-derived date palm (Phoenix dactylifera L.). III International Conference on Date Palm. Acta Hort. 736: 329-335. Al-Wasel AS. 2000. Phenotypic comparison of tissue culture-derived and conventionally propagated date palm (Phoenix dactylifera L.) cv. Barhee trees. I. Vegetative characteristics. J. King Saud University , Riyadh, Agric. Sci 1:65-73. Al-Wasel AS. 2001. Somaclonal variation in tissue culture-derived date palm (Phoenix dactylifera) trees. Proceedings of the Second International Conference on Date Palms. Al-Ain, United Arab Emirates, March 25-27, 2001. 2:588.

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Awad MA. 2007. Fruit set failure in tissue culture-derived date palm trees (Phoenix dactylifera L.) cv. Nabt Saif as affected by pollinator type and pollination density. III International Conference on Date Palm. Acta Hort. 736:441-448. Bamiftah MAO. 2000. Effect of potassium fertilization and bunch thinning on the yield and the annual of leaves and flower clusters of zahgloul date palms. Horticulture Section, Agricultural Research Center, Hadhramout Governorate, Yemen 15:134-141 Cohen Y, Korchinsky R, Tripler E. 2004. Flower abnormalities cause abnormal fruit setting in tissue culture propagated date palm (Phoenix dactylifera L.). J. Hort. Sci. Biotech. 79:1007-1013. Djerbi M. 2000. Abnormal fruiting of the date palm derived from tissue culture. Proceedings of The Date Palm International Symposium, Windhoek, Namibia, 22-25 February 2000:73. Fatehy H. 2004. Nutrients requirements of date palm and fertilizer use. Regional Workshop on Date PalmDevelopment in theArabian Peninsula. Abu Dhabi, UAE, May 29-31, 2004:278-286. Furr JR, Armstrong WW. 1955. Growth and yield of Khadrawy date palms irrigated at different intervals for two years. Date Growers Institute. 32: 3-7. Hajian S. 2007. Quantity and quality comparison of offshoot and tissue cultured Barhee date palm trees. Acta Hort. (ISHS) 736:293297 Khayyat M, Tafazoli E, Eshghi S, Rajaee S. 2007. Effect of nitrogen, boron, potassium and zinc sprays on yield and fruit quality of date palm. American-Eurasian J. Agric. & Environ. Sci. 23: 289-296. McCubbin MJ, Van Staden J, Zaid A. 2000. A Southern African survey conducted for off-types on date palms produced using somatic embryogenesis. Date Palm International Symposium. Windhoek, Namibia. 22-25 February 2000:41. Morsi ME. 2009. Response of date palm Seewy cv. Grown in new reclaimed to organic and inorganic nitrogen sources. Fayoum J. Agric. Res. & Dev.33:160-172. Reuther W, Crawford CL. 1945. Irrigation experiments with Deglet Nour dates. Date Growers Institute. 22:11-15. Sharples GC, Hilgeman RH. 1951. The influence of irrigation and bunch management upon shrivel of the Makhtoom date. Date Growers Institute. 28:9-11. Zaid A, Al-Kabbi H. 2003. Plant-off types in tissue culture-derived date palm (Phoenix dactylifera L.). Emir. J. Agric. Sci. 15:17-35.

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