LEAF PRUNING TECHNIQUE IN BEARING COCONUTS: ITS EFFECT ON UNDERPLANTING YOUNG COCONUTS FOR PITH OR UBOD PRODUCTION
G.D. Padrones, M.I. Secretaria[1], and S.S. Magat[2]
INTRODUCTION
Coconut is known as the “tree of life” because of its diversified products and by-products that support human life. Example of these is a food product locally known as ubod or coconut pith. This food item commands a considerable price in the market today because of its many uses. With modern food processing facilities, this terminal bud or coconut cabbage could be preserved (canned or bottled) and marketed locally and internationally as a food delicacy. Thampan (1975) referred to this preserved food item as the “millionaire’s salad.”
With the need for research and development on sustainable coconut farming, a research study on planting young coconuts under bearing palms with and without leaf pruning for ubod or pith production was undertaken. This system/strategy provides an alternative source for ubod, thus, preventing the indiscriminate cutting of productive coconut trees for such food purpose. The main objective of the study was to assess the feasibility of planting young coconuts under full-bearing palms with and without leaf pruning for ubod or pith production. Specifically, the study aimed to: 1) assess the performance of young coconuts planted in either single or in double plants per hill for ubod production under bearing palms with and without leaf pruning and 2) determine the cost and return of this production strategy.
MATERIALS AND METHODS
Experimental site
The study was conducted at the DavaoResearchCenter using a Tugbok clay loam reddish brown residual soil (Tropudalf soil taxonomy) with good external and internal drainage. The area has an elevation ranging from 120 m to 140 m above sea level. Benchmark soil analysis showed an average of pH of 6.5, exchangeable magnesium at 5.3 m.e./100 g soil, potassium at 0.45 m.e., calcium at 11.4 m.e., sodium at 0.08 m.e., and base saturation of 68%.
Experimental material
‘Laguna Tall’ (LAGT) seedlings were used as underplants under bearing 25-yr-old LAGT palms planted at a distance of 9 m x 9 m triangular system. The seedlings were planted in a 3 m x 3 m triangular system.
Experimental design and treatment
During the first 2 yr, the study was laid out in simple randomized complete block design (RCBD) in four replications with leaf pruning as treatment. Each plot was composed of 36 hills with two plants per hill or a total of 72 plants per plot. After 2 yr, the plots were split to accommodate the single and double underplanting scheme per hill. Henceforth, the study was laid out in split plot in RCBD where the main plot factor was leaf pruning (with and without leaf pruning) and the sub-plot factor was planting scheme (single and double planting).
Cultural management
All palms in each plot were circle-weeded within the root zone every 2 mo. The area was kept free of cover crops since spaces between main crops were planted to young palms. Both the full bearing palms and the young intercrop palms were applied with mineral fertilizers (ammonium sulfate and sodium chloride) in broadcast fork-in method at 2 m around the base of the palms and incorporated with soil. Double rates of fertilizers were applied in double plants per hill. Spraying of chemicals was done while seedlings were at their early stage.
Leaf pruning (LP) of bearing coconut trees
Bearing coconut trees with leaf pruning treatment were pruned from leaf rank number 19 (which supports the tender nut or buko) and below after every nut harvest, thus, 18 leaves were maintained in the coconut’s crown. This was done to increase light transmission to the underplants.
Soil and leaf sampling and analysis
Annual leaf sampling and analysis of both bearing (at leaf rank #14) and underplant coconuts (at leaf rank #3) were done by the Plant and Tissue Analysis Laboratory of PCA at Diliman, Quezon City to determine the nutrient status of palms as affected by the treatments. Soil sampling and analysis were done at the start, middle, and end of the study.
Data gathering
Data on nut and copra production from bearing palms were taken every 45 days and subsequently, nut sampling for copra determination. Growth observations, i.e., number of leaves produced by young intercrop palms were gathered every 6 mo. On the 3rd and 4th yr, ubod yield was assessed and marketing of harvested ubod was done.
RESULTS AND DISCUSSION
Effect of leaf pruning on:
Yield of bearing palms. No significant difference was noted in nut produced per palm between pruned and non-pruned coconuts from 1st to 4th yr of observation. However, coconuts with LP showed a slightly lower nut production per palm (an average of 11% reduction) over coconuts without LP (Table 1).
As to copra weight per nut, the palms with LP manifested a higher copra weight per nut over coconuts without LP. Likewise, no significant difference was observed on copra per palm for coconuts with and without LP. These results indicated that LP had no significant adverse effect on the yield of bearing palms.
Vegetative growth of young coconuts. Leaf pruning of bearing coconuts showed significant effect on the number of leaves produced, with young palms under pruned coconuts having more leaves than those under non-pruned coconuts (Table 2). This indicated that the young palms benefited from greater amount of light transmitted under pruned coconuts than those with non-pruned palms, thus, producing more leaves. Girth and total number of leaves were not affected by LP.
Effect of planting scheme on:
Coconut yield. Planting one or two underplants per hill did not show significant effect on all yield parameters of bearing palms, i.e., nut per palm, copra weight per nut, and copra weight per palm (Table 1). Generally, however, it could be observed that bearing palms with double underplants per hill had slightly higher yield attributes. This was possibly due to double dosage of fertilization on young coconuts, wherein the roots of bearing palms absorbed more nutrients from nearby double fertilized seedlings in one hill.
Vegetative growth of young coconuts. The girth size and number of leaves produced by the young coconuts showed significant effect of the planting scheme. Significantly bigger girth and greater number of leaves were observed from single plants than double plants per hill. This was obviously due to competition for light in double planting.
Effect of leaf pruning and planting scheme interaction
There was no significant effect of interaction between leaf pruning and planting scheme on the yield parameters of bearing palms, as well as on the growth parameters of young coconuts.
Leaf nutrient levels
Among the nutrient levels of bearing palms, only the Ca levels was significantly affected by LP, with palms with LP having higher Ca level than palms without LP. All other elements were not statistically affected by the treatments (LP and PS and their interaction) as all the palms from treated plots had nutrients above critical levels (Table 3a).
For the young underplants, all leaf nutrients were not significantly affected by leaf pruning and planting scheme (Table 3b). However, an interaction effect of these two factors was seen in leaf N and K. Under pruned coconuts, leaf N of young coconuts was higher in single planting, while under non-pruned coconuts, leaf N was higher in double planting. On the other hand, a reverse effect was noted in potassium, i.e. significantly higher leaf K was manifested in double planting under pruned pruned coconuts, while higher leaf K was observed in single planting under non-pruned coconuts (Table 3c).
‘Ubod” production
Three years after field planting of the underplants, 50% of the palms were harvested for ubod production. Another 50% were harvested on the 4th yr of planting. Harvesting was made on a selective basis, that is, palms with bigger bole were the first to be harvested.
The ubod produced both from single and double plantings was classified into large, medium, and small sizes (Table 4). Between the two planting schemes, the weight of ubod per plant from single planting was much heavier than that of double planting in all sizes on the 3rd and 4th yr. Likewise, girth or bole of young coconuts was bigger and the length of ubod produced was longer with single planting (Table 5). On the average, ubod yield per palm from single plant per hill did not manifest further improvement or increase in yield from 3rd to 4th yr of planting.
In the double planting scheme, ubod produced increased very slightly (only about 0.2 kg/palm from 3rd to 4th yr of planting (i.e. the 1st and 2nd ubod harvesting). These results indicate that there is no need to wait for the 4th yr for all young palms to be harvested since these palms have reached the optimum weight and length for a profitable net return. Besides, younger palms are a better source of ubod than older palms (Cinco and Pugoy, personal communication, 1997).
This result was corollary to that of Protacio and Ruanes (1995) except that their time of harvesting ubod was 2 yr from planting and the distance of planting young coconuts in open field was much closer to each other (1 m2 x 1 m2). In our present planting distance, the smaller palms are allowed to grow bigger due to more space despite two plants per hill. Hence, heavier and longer ubod were produced.
On a per hectare basis, total ubod yield was higher in double planting (average of 4,452 kg/ha/yr) compared to single planting with 2,467 kg/ha/yr. This was mainly due to the double planting density of young coconuts (1,484 palms/ha) in contrast to 742 palms in single planting scheme.
Economic analysis
Ubod production. Under single planting scheme, young underplants showed a total ubod yield of 2,522.8 and 2,411.5 kg/ha on the 1st and 2nd yr of harvest (3rd and 4th yr from planting). While there was no yield of ubod on the 1st and 2nd yr of planting, the net income from 3rd and 4th yr could compensate for the net loss incurred in the previous years (Table 6a). Hence, on a yearly basis, single planting scheme could generate an average net income of PhP 17,156 with an average return on investment of 163%.
Compared to single planting, the double planting scheme produced higher net income of PhP129,030 in 4 yr or an average yearly net income of PhP 32,258 with ROI of 180% (Table 6b).
Copra production. A positive ROI was obtained for 4 yr from copra production of bearing palms (Table 7). As a result of slightly higher yield attributes of bearing palms with double underplanting, a slightly higher average net income was recorded for this scheme (PhP 28,669/ha/yr) as compared to PhP 28,028/ha/yr from single planting. Consequently, a slightly higher ROI was incurred from double planting scheme.
Cumulative copra and ubod production. Cost and return analyses for combined copra and ubod production from bearing and young coconuts, respectively, revealed an encouraging ROI from the two planting schemes (Table 8). Both schemes in combination with copra production indicated a 202% - 203% ROI. The higher net income and ROI obtained in double planting could be attributed to better yield of bearing palms brought by the benefits obtained from double fertilization of young coconuts, and to the higher number of palms harvest for ubod production.
CONCLUSION AND RECOMMENDATION
Leaf pruning of bearing coconuts from leaf rank number 19 and below showed significantly good effect on the vegetative growth of young coconut underplants for ubod or pith production. This technique provides for sufficient light transmitted to young coconuts as intercrop. However, even without leaf pruning, young coconuts can be grown for ubod production under old existing palms.
Young coconuts could be planted in either single or double plants per hill in a 3 m x 3 m triangular system under bearing palms. Although the single planting scheme produced bigger and longer ubod per palm, the double planting scheme still produced higher total ubod yield per hectare per year due to its higher planting density. Consequently, higher net income was obtained from double planting than single planting scheme. Furthermore, bearing coconut trees benefited more due to more nutrient absorption from double planting, thus, the cumulative higher net income and ROI.
Based on the results of this study, planting two palms per hill under coconut trees for ubod production is a more profitable and viable production scheme to increase coconut farm productivity. The best time to harvest coconut trees for ubod production is on the 3rd yr from planting. There is no need to wait for another year to harvest all palms for this food purpose.
This production strategy offers an alternative source of producing coconut pith without cutting the existing productive coconut trees. This could contribute to the conservation of natural resources such as coconut trees, thereby maintaining the natural balance of the ecosystem. Likewise, with the increasing demand for this food item in our growing population, it is best to try this production scheme in existing coconut-bearing trees.
REFERENCES
CINCO, O.L. 1997. Personal communication, as Market Bankerohan Vendors Association, DavaoCity. “Prospects of ubod production: Younger palms, better source of of ‘ubod’ than older palms.”
PROTACIO, C.M. and D.A. RUANES. 1997. Alternative production technology for coconut ubod. Abstracts of papers presented at the Annual Scientific Conference of the Federation of Crop Science Societies of the Phil. (FCSSP), BaguioCity, 25-29 May 1997.
PUGOY, R. 1997. Personal communication. (Ubod dealer) Bankerohan Vendors Assoc. “Prospects of ubod production: Younger palms, better source of of ‘ubod’ than older palms.”
THAMPAN, P.K. 1975. Minor product of food value. The coconut palm and its products. Green Villa Publ. House. p.302.
TABLE 1
Annual nut and copra yield of bearing LAGT palms intercropped with young palms for ubod production
TREATMENT / NUT/PALM (NO.) / COPRA/NUT / COPRA/PALMY1 / Y2 / Y3 / Y4 / Y1 / Y2 / Y3 / Y4 / Y1 / Y2 / Y3 / Y4
A. Leaf Pruning (LP)
W/o LP / 97.3 / 75.5 / 89.7 / 89.6 / 272.4 / 320.9 / 317.1 / 304.3 / 26.3 / 24.8 / 28.6 / 27.27
With LP / 97.0 / 62.3 / 81.0 / 76.1 / 272.0 / 330.4 / 334.0 / 313.7 / 26.4 / 20.4 / 27.1 / 23.87
B. Planting Schemes (PS)
Single P/hill / - / - / 85.9 / 81.8 / - / - / 320.7 / 305.8 / - / - / 27.5 / 25.0
Double P/hill / - / - / 84.4 / 83.8 / - / - / 330.4 / 312.2 / - / - / 28.0 / 26.2
Stat. Sig. (LP) / Ns / Ns / Ns / Ns / Ns / Ns / Ns / Ns / Ns / Ns / Ns / Ns
(PS) / - / - / Ns / Ns / - / - / Ns / Ns / - / - / Ns / Ns
LP vs PS / - / - / Ns / Ns / - / - / Ns / Ns / - / - / Ns / Ns
% CV (LP) / 17.2 / 13.6 / 31.6 / 13.9 / 4.7 / 4.8 / 12.2 / 5.1 / 17.4 / 15.2 / 34.1 / 13.2
% CV (PS) / - / - / - / 14.6 / - / - / - / 4.1 / - / - / - / 15.4
TABLE 2
Growth observations on underplanted young palms for ubod production
TREATMENT / GIRTH SIZE (cm) / TOTAL LEAVES PRODUCED (NO.) / LEAF PRODUCED WITHIN 6 MO (NO.)A. Leaf Pruning (LP)
Without LP / 99.3 / 11 / 3.6b
With LP / 98.4 / 8.1 / 3.8a
B. Planting Schemes (PS)
Single P/hill / 108.1a / 11.7 / 3.9a
Double P/hill / 89.6b / 7.4 / 3.4b
Stat. Sig. (LP) / 108.1a / Ns / *
(PS) / 89.6b / Ns / **
LP vs PS / Ns / Ns / Ns
% CV (LP) / 19.0 / 68.8 / 5.04
% CV (PS) / 10.8 / 68.9 / 6.02
TABLE 3a
Leaf nutrient levels of bearing palms (leaf rank #14) at 25 yr old
TREATMENT / LEAF NUTRIENT (% DRY MATTER, LEAF RANK #14)N / P / K / Ca / Mg / Na / Cl / B (ppm)
Leaf Pruning (LP)
Without LP / 1.84 / 0.130 / 1.32 / 0.38b / 0.26 / 0.09 / 0.76 / 9.9
With LP / 1.85 / 0.140 / 1.23 / 0.40a / 0.26 / 0.09 / 0.76 / 10.0
Planting Schemes (PS)
Single Plant / 1.82 / 0.140 / 1.24 / 0.40 / 0.26 / 0.09 / 0.75 / 10.0
Double Plant / 1.87 / 0.130 / 1.32 / 0.39 / 0.25 / 0.08 / 0.77 / 9.9
Stat. sig.
LP / Ns / Ns / Ns / * / Ns / Ns / Ns / Ns
PS / Ns / Ns / Ns / Ns / Ns / Ns / Ns / Ns
LP x PS / Ns / Ns / Ns / ns / Ns / Ns / Ns / Ns
% CV (LP) / 8.66 / 8.92 / 44.75 / 9.86 / 25.20 / 77.95 / 23.32 / 27.43
% CV (PS) / 7.16 / 5.47 / 29.09 / 31.09 / 29.34 / 64.87 / 24.71 / 21.65
TABLE 3b
Leaf nutrient levels of young underplants (leaf rank #3) at 4 yr old
TREATMENT / LEAF NUTRIENT (% DRY MATTER, LEAF RANK #14)N / P / K / Ca / Mg / Na / Cl / B (ppm)
Leaf Pruning (LP)
Without LP / 1.8 / 0.125 / 1.86 / 0.43 / 0.41 / 0.23 / 0.81 / 13.4
With LP / 1.87 / 0.125 / 1.81 / 0.44 / 0.38 / 0.22 / 0.80 / 13.4
Planting Schemes (PS)
Single Plant / 1.90 / 0.130 / 1.82 / 0.44 / 0.39 / 0.21 / 0.77 / 13.5
Double Plant / 1.85 / 0.120 / 1.86 / 0.44 / 0.40 / 0.22 / 0.83 / 13.5
Stat. sig.
LP / Ns / Ns / Ns / Ns / Ns / Ns / Ns / Ns
PS / Ns / Ns / Ns / Ns / Ns / Ns / Ns / Ns
LP x PS / ** / Ns / ** / Ns / Ns / Ns / Ns / Ns
% CV (LP) / 4.78 / 3.20 / 11.34 / 8.64 / 13.36 / 71.03 / 16.95 / 15.61
% CV (PS) / 7.45 / 7.50 / 13.17 / 17.86 / 13.50 / 42.20 / 18.93 / 27.46
TABLE 3c
Interaction effect of leaf pruning and planting scheme on leaf N and K of young palms
TREATMENT / LEAF NUTRIENT% N / % K
Leaf Pruning (LP) / Planting scheme
Without LP / Single plant / 1.87ab / 1.90a
Double plant / 1.89ab / 1.82ab
With LP / Single plant / 1.93a / 1.73b
Double plant / 1.81b / 1.89a
TABLE 4
Average weight of ubod per palm at 3rd and 4th yr from planting
TREATMENT / CLASS / AT 3RD YR(kg) / At 4TH YR
(kg) / AVERAGE
(kg)
A.Single plant/hill (SP) / Large / 10.9 / 10.4 / 10.7
Medium / 6.2 / 6.1 / 6.2
Small / 3.4 / 3.1 / 3.3
Average / 6.8 / 6.5 / 6.7
B. Double plant/hill / Large / 9.9 / 8.8 / 9.4
Medium / 5.7 / 6.1 / 5.9
Small / 2.1 / 3.5 / 2.8
Average / 5.9 / 6.1 / 6.0
TABLE 5
Girth size (bole) of harvested young palms and length of ubod in relation to different sizes of ubod (average of the 4th yr harvest)
PARTICULAR / CLASSIFICATIONLarge / Medium / Small / Average
A. Single plant/hill
Girth (cm) / 125.6 / 111.4 / 87.5 / 108.2
Length (cm) / 30.9 / 26.6 / 21.1 / 26.2
B. Double plant/hill
Girth (cm) / 96.0 / 88.5 / 84.4 / 89.6
Length (cm) / 28.1 / 25.1 / 22.3 / 25.2
TABLE 6
Cost and return analysis of ubod production per hectare from young coconuts
A. Single plant/hill
YEAR / Ubod Yield/Palm / Ubod Yield/Ha / Gross Income3 / Total Cost / Net Income/ / ROI4(kg) / (kg) / (PhP) / (PhP) / Net Loss (PhP) / (%)
1 / - / - / - / 17,455 / (17,455)
2 / - / - / - / 7,394 / (7,394)
3 / 6.81 / 2,522.8 / 50,456 / 11,543 / 38,193
4 / 6.52 / 2,411.5 / 60,288 / 5,728 / 54,560
Total / 13.3 / 4,934.3 / 110,744 / 42,120 / 68,624
Average / 6.7 / 2,467.2 / 55,372 / 10,530 / 17,156 / 163
B. Double plant/hill
YEAR / Ubod Yield/Palm / Ubod Yield/Ha / Gross Income3 / Total Cost / Net Income/ / ROI4(kg) / (kg) / (PhP) / (PhP) / Net Loss (PhP) / (%)
1 / - / - / - / 29,550 / (29,550)
2 / - / - / - / 12,628 / (12,628)
3 / 5.9 / 4,377.8 / 87,556 / 19,127 / 68,429
4 / 6.1 / 4,526.2 / 113,155 / 10,376 / 102,779
Total / 12.0 / 8,904.0 / 200,711 / 71,681 / 129,030
Average / 6.0 / 4,452.0 / 100,356 / 17,920 / 32,258 / 180
1 Average yield of ubod/palm (3rd yr).
2 Average yield of ubod/palm (4th yr).
3 Ubod price = PhP20.00/kg – 3rd yr; PhP25.00/kg – 4th yr.
4 Return on investment.
TABLE 7
Cost and return analysis of copra production of bearing palms
A. Single plant/hill
YEAR / Copra Yield/Palm / Copra Yield/Ha / Gross Income1 / Total Cost / Net Income/ / ROI2(kg) / (kg) / (PhP) / (PhP) / Net Loss (PhP) / (%)
1 / 26.4 / 3,775.2 / 30,201.6 / 13,411 / 16,791 / 125
2 / 22.6 / 3,231.8 / 32,318.0 / 10,902 / 21,416 / 196
3 / 27.5 / 3,932.5 / 43,257.5 / 10,452 / 32,806 / 314
4 / 25.0 / 3,575.0 / 53,625.0 / 12,525 / 41,100 / 328
Total / 101.5 / 14,514.5 / 159,402.1 / 47,290 / 112,113
Average / 25.4 / 3,628.6 / 39,850.5 / 11,823 / 28,028 / 241
B. Double plant/hill
YEAR / Copra Yield/Palm / Copra Yield/Ha / Gross Income1 / Total Cost / Net Income/ / ROI2(kg) / (kg) / (PhP) / (PhP) / Net Loss (PhP) / (%)
1 / 26.4 / 3,775.2 / 30,201.6 / 13,411.0 / 16,791 / 125
2 / 22.6 / 3,231.8 / 32,318.0 / 10,902.0 / 21,416 / 196
3 / 27.9 / 3,989.7 / 43,886.7 / 10,577.0 / 33,310 / 315
4 / 26.2 / 3,746.6 / 56,199.0 / 13,040.0 / 43,159 / 331
Total / 103.1 / 14,743.3 / 162,605.3 / 47,930.0 / 114,676
Average / 25.8 / 3,685.8 / 40,651.3 / 11,982.5 / 28,669 / 242
1Copra price per kilogram: 1st yr – PhP8.00; 2nd yr – PhP10.00; 3rd yr – PhP11.00; 4th yr – PhP15.00
2 Return on investment
TABLE 8
Cost and return analysis of copra and ubod production of bearing and young coconuts per hectare
A. Single plant/hill
YEAR / Yield/ha/yr (kg) / Gross Income / Total Cost / Net Income/ / ROIUbod / Copra / (PhP) / (PhP) / Net Loss (PhP) / (%)
1 / - / 3,775.20 / 30,201.60 / 30,866.00 / (664.40)
2 / - / 3,231.80 / 32,318.00 / 18,296.00 / 14,022.00
3 / 2,522.80 / 3,932.50 / 93,713.50 / 21,995.00 / 71,718.50
4 / 2,411.50 / 3,575.00 / 113,913.50 / 18,253.00 / 95,660.00
Total / 4,934.30 / 14,514.50 / 270,146.10 / 89,410.00 / 180,736.10
Average / 2,467.20 / 3,628.60 / 67,536.50 / 22,352.50 / 45,184.00 / 202
B. Double plant/hill