AVAILABLE VARIETIES

The varieties of coconuts on which I was to experiment on Mr. F. Duncan’s plantation, Mua on Taveuni were the so called Malayan Dwarf, an imported variety from the Federated Malay States, and the Fijian Dwarf or Niu Leka. The trees were planted in January, 1922, and it was in August, 1925, that the first tree commenced flowering. In August, 1926, there were 48 trees flowering, and in bearing, of which 21 were selected for experiments.

There are two types of Malayan Dwarf: one with apricot coloured nuts and a yellow or reddish hue all over the spathe stalks, and mid-ribs, and another with slightly smaller, greenish or ivory-yellow nuts, and a paler green colour in stalks and mid-ribs. Of the latter type only one tree was used for experiments.

In an essay on Dwarf Coconuts in the “Malayan Agricultural Journal,” Vol. XII, No. 11, November, 1924, H.W. Jack points out that there are three distinct types of Malayan Dwarf, apricot, green and ivory-yellow. “These Malayan Dwarfs are locally known in Malaya as Niur gading, and are supposed to have been imported from Java, district Krian.” Further on he writes: “On existing plantations these types are intermingled with each other and with ordinary talls and semi-tells though the ivory-yellow type predominates.” The Malayan Dwarf could, except for the three colours in nuts, be called a pure line.

The Niu Lekas, however, is a group. or population, with distinct types, although all are more or less early bearing. It may be possible to divide these Niu Lekas according to colour, and shape of the nuts and the diagrams of the spathes into groups. Though these groups are certainly not pure lines, through breeding from distinct types only and by keeping them well isolated. it may be possible to obtain very useful material for crossing with other good types, or with imported strains.

There are many types among the Niu Leka with rather short leaves, though the majority have heavy mid-ribs with a broad foot gripping round the stem of the tree. The general appearance of the crowns is heavy and dense, but strong. However, a few trees can be found with slightly longer leaves, thinner mid-ribs and a much more open crown. with long spathes, being at the same time fairly heavy producers.

The inflorescences of the Niu Lekas differ in many ways from those of the Malayan Dwarfs. Not only are there red and green nuts, round and long shaped nuts, trees with heavy dense crowns, and trees with open, airy crowns, long leaves with thin mid-ribs and short leaves with very heavy and broad mid-ribs, but all these types have variable inflorescences.

The diagrams show some of the variations very plainly. The number of branchlets of the spadices varies from 49 to 76. Some trees have never more than one female flower per branchlet – others have no female flowers on the first 10 to 14 branchlets. Again others have very few female flowers on the lower branches, or very few on the top branches. Or one spadix may have 58 branchlets all crowded on a stalk 30 inches long, while other trees have only 50 branchlets on stalks of 5 feet in length. In the latter case the nuts will have more room for development and less chance of pushing one another from the stalk.

The shape and size of the female flowers of the Niu Lekas varies greatly. As a rule the stigmas are smaller than those of the Malayan Dwarfs, although the female flower in full receptivity may be larger.

The male flowers of the Niu Lekas are mostly different from those of the Malayan Dwarfs. They are not so pointed as a rule. and placed closer together and very often in pairs. When the branchlets are very short, and the number of flowers large, they are so crowded together that they take a shape according to the space they have to develop in. In general, the Niu Lekas have more male flowers on a branchlet than the Malayan Dwarfs, and the branchlets also are more numerous; consequently, there is a greater abundance of pollen in the Niu Leka spathe, which makes collecting easier.

Another rather early bearing variety which may prove very useful for breeding purposes is the Rotuma nut. There happened to be a complex of about 40 acres of Rotumas on Mrs. Mackenzie’s Plantation, Nagasau on Taveuni, where I was kindly offered the opportunity to make pollination experiments.

The Rotumas bear a larger size nut than the ordinary tall coconut and with thicker meat. In order to breed improved Rotuma stock it will probably be advisable to carry out artificial pollinations on selected superior trees on the island of Rotuma, where in all probability the variety has been kept rather pure through the isolation of the island.

On a fourth local variety, the common tall Fiji coconut, no pollination experiments have as yet been carried out. For such a purpose it will be necessary to produce a complex of young trees not too high, kept in so good a condition that very healthy superior types may be selected.

M.N. Islam I, M.F. Hossain2, M.A. Hossain3, M.I. Is/am4, M. Rafiuddins, M. F. Ahmed6, R. AI17

An investigation was carried out at the Regional Agricultural Research Station (RARS), Bangladesh Agricultural Research Institute (BARI), Jessore, during the period of May 2006 to May 2008 to control distortion and immature bud drop, Two experiments were designed to achieve the objectives. Foliar application of Oomite (miticide) and soil application of boron (in the form of boric acid) at different doses were used in first experiment while Oomite in second experiment was applied at different doses followed by removing of infected nuts and inflorescence. Application of boron could not cure the dryness appearance of pericarp but improve the skin color of immature nut. Application of 0.15% to 0.2% Oomite significantly reduced dryness appearance of newly born nut. Based on the results of the 1st experiment, palms when treated with 0.2% Oomite after removing of newly born inflorescences as well as infected young nuts, no infections were noticed in subsequent bunches.

INTRODUCTION

Coconut is considered a high value crop. Any pal1 of coconut gives income if processed into value added products. The growers of coconut in Bangladesh are smallholders while some are landless or marginal. It is mainly grown at the homesteads in Bangladesh. Orchard plantation seldom found in the coastal belt of the country. Tall type coconut cultivars are generally found to grow everywhere in the country, which is highly resistant to many biotic and abiotic stresses. However, very recently, coconut palms are found to suffer from reduction in size of nut followed by immature bud dropping (Figure I). The problem has become epidemic in south and southwestern parts of the country. The incidence of such problem is quite new to the farms. Review of literature reveals that such problem was first repol1ed in Jamaica in 1991 and one kind of microscopic mite injured the nut at the region of perianth which expanded on the surface of nut with the increase of nut age (Griffith 1984). In the lndo-sub-continent. it appeared first in Sri Lanka in 1998 and spread in South-India states in 2002. In Bangladesh, the incidence of mite appeared first in 2004. Boron deficiency may sometimes cause bud drop or nut malformation due to failure of successful pollination (Alfanso et al. 1999). Therefore. the study was undertaken to find out the role of boron and miticide on nut distortion and bud drop of coconut.

1 Senior Scientific Officer (Horticulture), Regional Agricultural Reseatth Station, Jessore, BANGLADESH.

2 Scientific Officer (Horticulture). Regiona! Agricultural Research Station. Jessore, BANGLADESH.

3 Senior Scientific Officer (Soil Science), Regional Agricultural Research Station. Jessore, BANGLADESH.

4 ScientifIC Officer (Entomology). Regional Agricultural Research Station, Jessore. BANGLADESH.

5 Senior ScientifIC Officer (Horticulture), Regio!1a} Agricultural Research Station, Jessore, BANGLADESH.

6 Pnncipal Scientific OffICer (Plant Pathology). Regional Agricuitural Research Station. Jesso,e, BANGLADESH. 7 Chief ScientifIC Officer and Plant Breeder, Regional Agricultural Resesrc/! Station. Jessore, BANGLADESH.

01

Figure 1

Mite-infected nuts.

MATERIALS AND METHODS

The experiment was conducted in the coconut orchard of Regional Agricultural Research Station, Jessore, Bangladesh from May 2006 to May 1008. In the first year. 48 infected palms were selected for the study (Figure 2). The experiment was laid out in RCB factorial design with three replications. There were 16 treatment combinations. Four levels of boron, O. 20, 40 and 60 g/tree, in the form of boric acid and four levels of miticide Oomite (57EC), 0, 0.1 0.15, 0.2% were combined for allocating in each replication. Chemical ingredient of Oomite is 570g propergite/L, distributed by an Italian Company. UNIROYAL Ltd. and imported in Bangladesh by SHETU Corporation. Dhaka, a multinational insecticide company), Boric acid (in powder form) was applied followed by dibbling method. Oomite \vas sprayed immediately after opening of inflorescences and on young leaves. Spraying was done between 8-IOam and the schedules were continued up to 6 mo at 15 days interval. Based on the result of first experiment, Oomite at the rate of 0.2% was sprayed in 2nd yr experiment as follows:

T ₁,- removing all fruits and flowers and spraying Oomite

T ₂- removing of flowers and fruits up to 6 mo old and spraying Oomite

T ₃- spraying of Oomite without removing of any fruits or flowers

The palms were kept under closed observation. Data were recorded on number of fruit before the study, date of flowering, number of nuts at harvest, and surface damage of nuts at the age of 8 mo. Extent of damage was estimated by scoring 1 to 10 visual scales by modification of Moore et al. (1989) (Figure 3).

Grade 0 – nuts with no mite damage

Grade 1 . nuts with 1-29% surface area damage

Grade 2 – nuts with 30-59% surface area damage and less than 20% reduction in size

Grade 3 – nuts with 60-80% surface area damage, 20-30% reduction in size

Grade 4 – nuts with over 80% surface area damage, over 30% reductions and greatly deformed

Collected data were summarized and analyzed; statistically means were separated by DMRT to interpret results. Initial fruit numbers were used as baseline information to compare the yield.

02

Figure 2

Infected palm a9.d nuts.

Figure 3

Grading of mite-Infected nuts.

RESULTS AND DISCUSSIONS

Soil application of boron found to improve greenness of nut at early stage of growth but could not remove dryness appearance and distortion. Scoring of dryness symptoms was found to range from 2.83 to 5% (Table 1). Number of bunches as well as fruits per palms receiving no boron were initially found significantly higher. Application of boron was found to increase flowering and fruits set. As a result. no significant differences in bunch and fruit numbers of boron-treated palms were observed as compared to that of control. The results agreed with Alfanso et al. (1999) who stated that boron is essential for successful fertilization and fruit set. The percentage of CV of each character was very high because the infected palms were selected randomly and there was wide variation in number of fruits and bunch among the palms initially. Dryness appearances found to reduce when bunches were sprayed with 0.15% and 0.2% Oomites (Table 2). No interaction effects noti.ced between boron and Oomite application (Table 3). Palms

03

treated with 0.2% Oomite after removing all fruits and inflorescences or young nuts up to 7 mo old showed no discoloration of newly born nuts (Table 4). The result supports the findings of Griffith (1984) who reported that the mites hide in the perianth of young nuts and suck nutrients from there. He also reported that. when nut age reached 7 mo or above. flows of nutrients from the leaves of palms to the nut reduced. So, mites from the old bunches move to the new inflorescences for foods. If the palms have no fruits, mites go to the young leaves, where palms’ supply comparatively higher nutrients. So. removing.inflorescence and young nuts make palms free from mites while foliar application of Oomite effectively controls the mite (Figure 4).

Figure 4

Infected palms after treatment.

Table 1

Effect of Boron on fruit set and dryness appearance of pericarp

Means with the same letter in a column do not differ significantly.

B₁; 0 g/plant. B₂, 20 g/plant. B₃, 40 g/plant and B₄, 60 g/plant

Table 2

Effect of Oomite on development of pericarp spot of coconut

Means with the same letter in a column do not differ significantly.

S₁= 0 mL/L of water. S₂= 1 mL/L of water, S₂= 1.5 mL/L of water, S₄= 2.0 mL/L of water

04

Table 3

Combined effect of Boron and Oomite on development of pericarp spot of coconut

NS= non significant

Table 4

Effect of removal of flower and fruit on controlling of spots on pericarp of coconut

Means with the same letter in a column ere not significantly different

(Within the parenthesis transformed value of the original data)

CONCLUSION AND RECOMMENDATION

Reduction of extent of damage by foliar application of Oomite indicated that mite might cause the damage. Infected palms should be treated with Oomite @ 1.5% after removing inflorescences and young nuts for effective control. Considering the extent of damage and economic losses to the farmers, further large scale investigations in the farmer’s fields are necessary to confirm the real cause of the damage.

05

ACKNOWLEDGMENT

The authors would like to thank the field workers why have climbed up the palms and helped in spraying, and recording of data. Our gratitude is also due to Senior Scientific Assistant Mr. Dilip Kumar for extending labour support to carry out the study.

REFERENCES

ALFANSO, A.. MA ARCELlA, S. DIONISIO and L. MARIBEL. 1999. Fundamental of Plant Physiology. Plant Physiology

Society of the Philippines. Pasig City, Metro. Manila. 166 pp.

GRIFFITH. R. 1984. The problem of the coconut mite. E. guerreronis Keifer. in the coconut groves of Trinidad and Tobago.

Carib. Food Crops Soc. 20:128.123. Also published in J. Agric. Soc. Trin. and Tab. 85:81.99.

MCCOY. C.W. and LG. ALBRIGO. 1975. Feeding injury to the orange caused by the citrus Rust mite. Pl1y/locoptruta

o/eivora (prostigmata: Eriophyoidae). Ann. Entoma!. Soc. Amer. 68:289-297.

MOORE. D., L. ALEXANDER, and R.A. HALL. 1989. The coconut mite, E. guerreronis Keifer in SI. Lucia: yield losses and

attempt to control it with acaricide. polybutene and Hirsutella fungus. Trap. Pest Manag. 35:83.89.

Agricultural Plough,
Spring Loaded Tiller,
Offset Disc Harrow
Agricultural Motors,
Agricultural Pumps,
Irrigation Pumps
Garden Rake,
Pinch Point Bars,
Pick Axe,
Posting Digger,
Chisel Tools
Agricultural Implements,
Cutter Mattock,
Rail Road Pick Rotary Tiller,
Rotary Tiller Spare Parts,
Harvester Combine,
Header Spare Parts
Paddy Thrasher,
Groundnut Decorticators,
Chaff Cutters Agricultural Hoes,
Agricultural Shovels,
Agricultural Plouges
Agricultural Chain,
Agricultural Finger,
Stainless Steel Pulley
Agricultural Pump,
Horticultural Pump,
Water Lifting Pump,
Gear Pump,
Piston Pump
Coconut Fiber De husking Machine,
Coconut Palm Leaves Cutting Machines,
Paddle Mixer Machines Agriculture Machines,
Maize- Sheller, Paddy Thrashers Agricultural Equipment Spare Parts,
Farm Equipment Spare Parts,
Garden Equipment Spare Parts
Agriculture Pumps,
E centric Screw Pumps
Chaff Cutters,
Flour mills- Third Pedestal,
Flour mills- Half Cabinet,
Groundnut Decorticator,
Stainless Steel Pulverizer Paddy Rice Thresher,
Multi crop Thresher,
Maize Sheller Vegetable Nursery Transplanter,
Zero Till Multi crop Planter For Controlled Tractor Traffic,
Seed Cum Fertilizer Drill,
Aluminum Fluted Rollers Assembly,
Axial Flow Vegetable Seed Extractor
Tractor Trailer,
Disc Harrow,
Grass Cutter,
Land Leveler
Knapsack Sprayer,
Agricultural Knapsack Sprayer,
Knapsack Power Sprayer,
Knapsack Sprayer India,
Foot Sprayer.

The loss can be reduced to the minimum if palms could be attended immediately on appearance of symptoms and prophylactic and curative treatment for leaf rot is given to all palms in the disease prevalent areas twice a year. Management of leaf rot is very important in addition to irrigation and recommended dose of fertilizers and manures for the effective management of root (wilt) disease of coconut in heavily disease affected area.

Leaf rot being a major component in the root (wilt) disease complex contributing to rapid decline and reduction in yield, CPCRI has developed a very effective, easy to practice, labour saving and economically viable integrated management practice for the management of leaf rot disease and major pests occurring in heavily root (wilt) disease affected tracts.
• Cut and remove rotten portions of the spindle and the adjacent two innermost fully opened leaves, if affected by leaf rot. White soft leaflets of the spindle alone are susceptible to fungal attack. Therefore, older leaves that had leaf rot disease earlier need not be removed.
• Mix Contaf 5 EC (Hexaconazole) 2 ml or Indofil M-45 (Mancozeb) 3 g in 300 ml water and pour around the base of the spindle leaf.
• Apply 20 g Phorate 10G or 30 g Furadan 3G mixed with 200 g sand around the base of the spindle leaf.
• Treat all palms in the garden (healthy and diseased) twice a year, i.e. in April – May and October – November. To make this operation more economical the treatment should be given along with harvest of nuts before and after south – west monsoon.

Residue analysis done for the chemicals in mature and tender nuts showed that the nut water, kernel, coconut oil and coconut cake are free from residues after 45 days of application at the rates suggested above.

The strategy for mildly affected area is to contain the disease by removing all the diseased palms. Eradication of disease – affected palms to contain the disease can be successful if continuous monitoring for occurrence of the disease and uprooting of diseased palms in the very initial stage of the disease are taken you simultaneously. If the programme is not monitored uninterruptedly the desired goal will not be achieved.

The area under cultivation has more or less stagnated over the years, and with coconut oil prices decreasing, it is unlikely to show an improvement in the short-run, traders say. In 2003-04, 1,933,700 hectares were under coconut cultivation and in 2005-06, the area under cultivation improved marginally to 1,946,800 hectares. Kerala is the main coconut growing state, with an area of 897,800 hectares, followed by Tamil Nadu (370,600 hectares) and Karnataka (385,400 ha). Sources say that Tamil Nadu is likely to emerge the largest producer within a short span of time, given that the area under cultivation is decreasing in Kerala. Production has become unviable in Kerala, while productivity gains have helped Tamil Nadu stay profitable despite the lowering of coconut oil prices.

A study by the Kasargode-based Central Plantation Crops Research Institute (CPCRI) forecasts that the nut production will increase by 31.38% in 2007-08 over the base year 2003-04. Production for 2003-04 is recorded at 12.17 billion nuts. Production increased to 14.8 billion nuts in 2005-06, an increase of 21.62% over the base year. Interestingly, the rapidly increasing supply falls short of the long-term demand for nuts. A forecast study reports that the demand for coconut is expected to be 21,795 million nuts by 2025, while the supply is expected to be only 15,734 million nuts. There is a gap of 6,061 million nuts. As there is no scope for area expansion in India given the demand for land for various purposes, there is a need to increase the productivity further. The competitiveness of the sector will largely depend on the productivity of the crop. Today, one ha of coconut produces on an average only 0.6 tonne of oil, whereas one ha of oil palm produces nearly 3-5 tonne of palm oil. There is a need for a high degree of productivity improvement to survive the onslaught of competition when prices fall in the global market.

The Coconut Development Board has chalked out an ambitious plan for re-plantation of the crop and expansion of the area in non-traditional producing states. The objective of the programme is to achieve a level of annual production of 15 billion nuts by 2012.

The main constraint is that the price of coconut is largely based on the prevailing price of coconut oil. Though only 35% of the coconut produced in the country is used for extraction of oil, the entire coconut-based economic activities are dictated by the price of coconut oil. The sector in India provides employment nearly to 10 million farmers, makes a contribution of nearly Rs 7,000 crore annually to GDP and contributes 6% to the vegetable oil pool of the country.

The importance of the crop lies in the fact that it provides a livelihood and sustenance for the millions of small and marginal farmers.

In India, almost the entire production goes for internal consumption in the following pattern: about 47% for edible purpose, 28% for coconut oil, 11% for tender nut and 6% for edible copra. Global export of coconut products exceeds $1.2 billion annually.

Incredible India

Shedding of buttons in unusually high numbers is a matter deserving attention and adoption of remedial measures. Excessive shedding of buttons in coconut may be due to any one or more of the reasons such as insufficient pollination due to low population of pollinating insects, unfavorable conditions like drought and water logging, nutritional problems, pest attack and incidence of diseases. Tackling the problem of undue button shedding is sure to improve nut yield in coconut. Appropriate remedial measures are to be undertaken for identifying the causes for excessive button shedding.