Mechanisation of Starfruits Under High Density Planting System
12 A.W. Fazlil Ilahi and S.I. Syed Mohd1Automation and Mechanisation Programme
MARDI Research Station, Telong,
16310 Bachok Kelantan,
e-mail: email@example.com. 2Horticulture Research Center
P.O. Box 12301, 50774 Kuala Lumpur
Abstract 1.0 Introduction
Starfruits is one of the country's major fruits for Starfruits or Carambola is suffering a major export. The industry is however suffering a set setback in its production due to the high labour back due to lack of farm hands. With the requirement. Among the major operations, fruit prospect of expanding traditional overseas wrapping in particular takes about 45% of markets and potential new markets, research production cost. Evidently the production were conducted to minimise labour requirements dropped in line with the recent labour shortage through mechanisation. prior to the current economic downturn.
Production had decreased; in 1994 it was 39 750 Starfruit trees were planted in rows of 4 and 6m mt., while in 1996 it was 37 228 mt. apart. The trees were kept small through Nevertheless market demand is persistent. In systematic canopy pruning and root restriction. 1996, a total of 13 044 mt. of starfruits valued To ensure high light interception obtained by the at RM24.98 million was exported; where 60% orchard, planting densities were increased by went to Europe, 23% to Hong Kong, 29% to reducing within row spacing to 0.5 and 1 m. Singapore 20% and 2% to Canada. These This arrangement resulted in tree densities traditional markets are expanding with emerging ranging from 1,666 to 5,000 trees/ha as new markets in Eastern Europe, the Middle East, compared to only 277 tree/ha in conventional China and Korea. The fruit is identified as one system. of 15 fruit types destined for further
development in the third National Agricultural The trees were trained into T-shaped plant form Policy (1998 - 2010) (Izham, 1998). for highly mechanized system and Malaysian
(modified) spindle plant form for partially Present fruit production technology based on mechanized system. Results indicate that tree conventional planting system (Abd. Rahman et performance and mechanisation prospect are al. 1992) was not efficient due to inefficient satisfactory. Row planting facilitated resource utilisation and high labour requirement mechanised operations in fertilizer application, (Syed Mohd, 1991; Mohammed and Wilson, spraying of chemicals for pests and diseases 1984). Novel fruit production technology based control, weed control and in-field transportation. on High Density Planting (HDP) concept had A pruning machine assembly was deployed and transformed fruit production in Europe and other was able to save labour in routine maintenance advanced countries into a viable and profitable works. Where the shoots cannot be reached industry (Wagenmakers, 1994). As a result light "chemical pruning" is preferred. A beater is interception is enhanced, mechanisation and being developed for detaching ripe fruits in automation is made possible. High labour highly mechanized system. Use of insect requirement for tree pruning, fruit wrapping (and proofed netting especially to protect fruits from culling) and harvesting was identified as the fruit flies is imperative for both systems. main factors impeding increase in starfruit
production. It was estimated that 19 workers are mechanised approach, while at UPM was needed to wrap 332 trees (one hectare) at 400 targeted for partial mechanisation. fruits per tree within 7 days (Anon., 1988).
3.1 Highly mechanised system
The trees grow vigorously and pruning is often
needed. The growth is usually restricted by It was postulated that the use of medium sized bending vertical water shoots and tying them (25-30hp) tractor would be sufficient as a down to stakes or lower branches. Heavy primemover for initial observations. The trees pruning is usually required after the fifth year of were planted at MARDI research station in neat growth to keep the trees to a manageable height single rows and trained to a T-shaped for wrapping and harvesting operations. Thus, architecture. Henceforth once the desired size starfruit trees are still considered as unsuitable was obtained (about 2 years) it had to be pruned for large scale cultivation. Most of the present to maintain the form. T-shaped plant form was farms belong to individual owners with areas chosen based on the ease to mechanise pruning ranging from 0.5 ha. to 4.0 ha. (Anon. 1990). and harvesting operations. The idea was
mentioned in earlier papers (Syed Mohd, 1992; The fleshy five angled fruit tastes sweet to sour Syed Mohd and Fazlil Ilahi, 1995). and its colour is between glossy light green to
bright yellow becoming almost orange when Two treatments were initially laid out on two fully ripe, it has sweet aroma. The air smells 0.25ha. plots. First plot was 6m between sweet while the fruit is ripening; inviting rows and 0.5m within rows (3 320 trees/ha), common enemies; the fruit flies and other pests. next plot was 4 by 0.5m (10 rows, 5000 trees/ha) Fruit flies attack at a much younger stage (about and 4m by 1m (6 rows). Plot length was 3 weeks after fruit set). As a result, the fruits approximately 35m. Budgrafted B10 starfruit become worthless. Thus, one can say; “no planting material were planted in both plots. wrapping, no fruit”. Fruit loss is almost 100%. Later on insect proof netted structure was Blanket insecticide spraying is not constructed over the first five rows (4m x 0.5m), recommended, as this will also kill pollinators which will be extended to cover 3 additional and other beneficial insects. With proper rows. The trees were allowed to grow vertically sanitation and bait spraying technique, the attack during the first year along temporary slender is some what curbed. This practice is impractical wooden stakes. When sufficient height was in most cases, timeliness, weather and persistent reached two branches were selected and tied to attacks from neighbouring areas are among the wire trellis passing along well spaced T-frustrations experienced by farmers and shaped wooden stakes which were later replaced researchers. Perhaps there is a better way to by G.I. and mild steel pipes (Figure 1). produce starfruits.
The tress were irrigated using microjet system,
which was found to be troublesome as the ducts
became congested with ants especially during 2.0 Objective
dry seasons. Crop maintenance was done by
To evolve an alternative production system for utilising machineries bought to fit the system. starfruit industry that will reduce labour These were a 25hp. (2 wheel drive) four wheel requirements while maintaining fruit quality for tractor, a rotary slasher, a fertiliser bander cum both fresh and processed markets. broadcaster, a boom sprayer set and a fabricated
open trailer. A pair of electric hedge pruners and
a portable generator was bought for pruning
purposes by first mounting on the trailer. Later 3.0 Methods
this was installed at the front of the tractor Two trials were initiated. One at MARDI chassis and the generator on the 3-point linkage. Research Station, Jeram Pasu, Kelantan and the Pruning of water shoots on the main stem and other one at Universiti Putra Malaysia campus. sections close to the T-junction have to be done The one at MARDI was meant for highly manually. A side research is underway to screen
Figure 1. A sketch of trees trained to form T shape for highly mechanised planting system.
insert is a single tree trained to T form
potential chemicals for controlling (chemical Wong 1996, Syed Mohd, Wong and Izham pruning) those vigorous shoots. Only two boom 1998), (Figure 2).
sprayer nozzles on each side of the tractor were
used, boom width was adjusted to fit row width Partially mechanised system is different from such that areas about 1m wide on each side of highly mechanised system in two ways. Firstly, the row is covered (under the canopy), while the it was so called partially mechanised because end nozzle was inclined to enable the wider under this system, harvesting is done manually. reach. Manure and fertilisers were applied as Harvesting in highly mechanised system is recommended (Abd. Rahman et al, 1992). machine aided. Secondly, partially mechanised
system utilise Malaysian Spindle plant form The harvester would comprise of a beater which instead of T-shaped plant form. when activated will detach ripe fruits from their
stalk. This beater is a contraption that imparts Planting distance for partially mechanised energy to those twigs that bears ripe fruits. Since system was 1m by 4.5m. This is equivalent to 2 the beater is not available in the country, it had 222 trees/ha. All maintenance operations were to be designed and developed. Two prototypes similar to highly mechanised system except in were fabricated but failed. A third model is harvesting operation. Tree growth was being tested. controlled by restricting the root system in
porous membrane material which allow ground
water movement. Porous membrane material 3.2 Partially mechanised system
was laid as lining in planting furrows of 30cm Partially mechanised system was developed as a wide and 50cm depth. Detail of porous result of a series of experiments carried out at membrane technique was described elsewhere MARDI Research Station, Jeram Pasu, Kelantan (Syed Mohd and Wong, 1992). The plot was and at Universiti Putra Malaysia campus from irrigated and fertigated using automated system 1988 until 1998. Detail of experiments was as described by Syed Mohd, Wong and Izham reported elsewhere (Syed Mohd 1992, Syed (1998).
Mohd and Fazlil Ilahi 1995, Syed Mohd and