Coconut Research Institute Repository

Jayalath, K.V.N.N.

Pathiraja, P.M.E.K.

Jayasinghe-Mudalige, U.K.

Fernando, M.T.N.

An empirical investigation on the effect of land size on its productivity of coconut plantations in Sri Lanka

Senarathne, S.H.S.

Perera, K.C.P.

COCOS, 2010,19: 51-56 Printed in Sri Lanka RESEARCH ARTICLE Impact of Glyphosate on Weed Biomass and Growth of Coconut Seedlings in Nurseries S.H.S.Senarathne and KX.RPerera Coconut Research Institute, Lunuwila, Sri Lanka A B S T R A C T The effects of five different weed management systems on growth of coconut seedlings were evaluated to determine an economical and effective method for controlling weeds in coconut nurseries in the low country of the wet zone in Sri Lanka. The treatments comprised of manual weeding (T,), application of glyphosate at 1.44 kg ai/ha fT,), 1.08 kg ai/ha (T,), 0.72 kg ai/ha (T4) and 0.36 kg ai/ha (Ts) applied at three-month intervals. Treatments 1 and 2 significantly reduced the weed biomass when compared to other treatmetns. The growth of coconut seedlings (in terms of height and girth) increased significantly (P<0.05) with the application of glyphosate at 1.08 kg ai/ha (T3) at the end of the nursery growth period. At the higher concentration (1.44 kg ai/ha) the growth of seedlings was reduced at the latter part of the experiment. Therefore, the most cost-effective treatment of controlling weeds in the study was to apply glyphosate at the rate of 1.08 kg ai/ha (31 of commercial mixture/ha). Manual weeding was neither effective no economical. Key words: coconut, seedling, monocotyledonous weed, glyphosate INTRODUCTION Coconut (Cocos nucifera L.) is by far the most extensively cultivated major plantation crop in Sri Lanka (Liyanage and Liyanage, 1989). It is distributed in approximately 0.444 mn ha of land throughout the island (Central Bank, 2002). To establish and maintain proper plantation, a high quality coconut seedling are an essential perquisite. Annually more tiian 2 mn coconut seedlings are issued to the growers for their replanting program (Plantation Sector Statistical Book, 2002). Therefore, to produce high quality seedlings much attention needs to be paid during the nursery period. Coconut seedlings are raised in nurseries prior to field planting. Proper care and maintenance of seedbeds facilitate the selection of early germinating vigorous seedlings (Peries and Everard, 1993). The inheritance studies carried out by Liyanage and Abeywardana (1957) have showed that seedling vigor is correlated with adult palm characters such as early flowering and high nut and copra yield. In the nursery, apart from irrigation, weeding is very important though expensive. Good weed management can minimize economic losses as reported by Suryaningtyas (1997) and Wibawa (1997). Seedbeds should be weed free; otherwise weeds would compete with coconut seedlings for nutrient and moisture. Each weed species has different effect on growth of plants (Eaton 52 Senarathne et al., 1976). However, information on growth reduction of seedlings due to weed competition in the coconut nurseries in Sri Lanka is not available. The most popular method of weeding in coconut nurseries is hand weeding, which is labor intensive and time consuming (Remison & Mgbeze, 1987). Hand weeding has not been effective, especially for weeds with underground storage organs (Pethiyagoda, 1980). Chemical weeding is also adpted by nursery growers. Glyphosate has a systemic action and it is very effective to control grass weeds in coconut nurseries such as Imperata cylindrica, Cynodon dactylon, Panicum maximum and Cyperus rotundus. These are the common weeds in coconut nurseries of the wet zone. In Sri Lanka Cyperus rotundus is one of the major weed species found in wet zone coconut nurseries (Gunasekara and Fernando, 1994). Glyphosate is a widely used, non-selective, foliage applied herbicide which is known to be highly toxic to Panicum repens (Manipura & Somarathne, 1974). Glyphosate is also a commonly used herbicide in mature coconut plantations because it is non-selective and affects a wide range of monocotyledonous and dicotyledonous annuals, biennials and perennials (Boyall, 1998). However, glyphosate can be harmful to both weeds as well as coconut seedlings. Hence the objective of this study was to identify most economical and effective method of weed control in coconut nurseries. MATERIALS AND METHODS The experiment was carried out during October 2002 to June 2003 in a coconut nursery located at Wennoxuwa in the Low Country Wet Zone of North-Western province of Sri Lanka. The average day temperature at the site was around 27C0 and rainfall was uneven with dry spells. All the coconut seed nut were selected from high yielding mother palms. Seed nuts were laid in the nursery beds spaced at 45cm between rows and 15cm within rows in October 2002. Each experiment plot measured 2.5m x 3 .m containing 40 seed nuts within a nursery bed. The experiment was conducted in Randomized Complete Block Design with three replicates. The treatments were Manual weeding (T,), Glyphosate application at 1.44 kg ai/ha (J2), 1.08 kg ai/ha (T3), 0.72 kg ai/ha (TJ; 0.36 kg ai/ ha (T5) and T6 - No weed control. Glyphosate was applied uniformly over the plot using a hand sprayer at three months intervals starting from October 2002 and ending in May 2003. Weed biomass: The weed biomass was collected every month form 0.25m x 0.25m quadrates from four random points per plot. The weeds were separated into species and dried to constant weight at 80 0C for five days from October 2002 to May 2003. Coconut seedling girth and height: Ten coconut seedlings were selected randomly and plant height and stem girth (base of the seedling) were measured. Data analysis was conducted using Analysis of Variance (ANOVA) using Statistical software and the significance was tested using the Least Significant Differences (LSD) (P=0.05) (SAS Institute 1999). RESULTS AND DISCUSSION Effect of different glyphosate concentrations on weed biomass: Major weed 53 Impact of glyphosate on weed biomass and growth of coconut seedlings in nurseries species in this site were Imperata cylindrica, Panicum repens. Cynodon dactylon, Chloris barbata, Mimosa pudica, Urena lobata, Croton hirtus, Allmania nodiflora, Mitracarpus villosus, Tephrosia purpurea, Vernonia cinerea, Tridax procumbens, Sida acuta, Scoparia dulisis, Stachytarpheta jamaicensis and Hyptis suaveolens. Weed biomass was lowest in plots which received 1.44 kg ai/ha and 1.08 kg ai/ha of glyphosate respectively (Fig. 1). At the lowest concentration of glyphosate (0.36 kg ai/ ha) (Tj) and in manual weeding (T () treatments were not sufficient to suppress the weed population satisfactorily. However, Glyphosate application at 1.44 kg ai/ha (T2), 1.08 kg ai/ha (T,) and 0.72 kg ai/ha (TJ were found to be parts could not be destroyed. Therefore, weeds appeared within a very short period of time. However, dicotyledonous weeds were very easy to control manually. Boyall (1979) showed that when glyphosate was applied; it is trans­located to underground rhizomes and destroys all-visible buds. Therefore, the best method of eradicating monocotyledonous weeds is the application of glyphosate. Seed bank of weeds in the soil creates new weed populations, which predominantly comprise of dicotyledonous weeds. Effect of glyphosate on coconut seedling growth: Glyphosate 1.08 kg ai/ha (3 1/ha) significantly increased (P<0.05) the height and girth of seedlings compared to other treatments Thu • (mentha) - H m d — « H n q m QNphOMla 1.441c (MM Q l y p M a u a 1 M h) , M OlyphMMo 0.72 I g alf ltt u QlyplMMaM I M H) *1A<* Figure 1: Effect of treatments on weed biomass (g m2) effective in reducing both monocotyledonous (Tables 1 & 2). This increase started from the and dicotyledonous weeds? latter part of the nursery growth period with the , , reduced competition of weeds for.soil moisture When manual weeding, fast re-growth, and nutrients. especially monocotyledonous weeds was observed, as under ground vegetative plant Senarathne Table 1: Effect of weed control treatments on collar girth (cm) of coconut seedlings from October 2002 to May 2003 Time (month) Treatments Feb Mar April May June 2003 2003 2003 2003 2003 Tp Manual weeding 5.28 7.27 9.08 11.15 13.10 T r Glyphosate 1.44kg ai/ha 6.01 7.65 9.30 12.25 12.70 T 3 - Glyphosate 1.08kg ai/ha 6.21 7.64 9.36 12.50 14.83 T«- Glyphosate 0.72kg ai/ha • 5.98 7.78 9.60 12.25 13.80 T5- Glyphosate 0.36kg ai/ha 5.82 7.22 8.80 10.94 13.09 T e - Unweeded control 6.02 7.32 8.02 9.96 12.30 LSD (P=0.05) - - 0.93 0.79 1.80 CV% - -5.69 3.81 4.37 Table 2: Effects of weed control treatments on height (cm) of coconut seedlings from October 2002 to May 2003 Time (month) Treatments Feb Mar April May June 2003 2003 2003 2003 2003 Ti- Manual weeding 54 63 82 97 107 T r Glyphosate 1.44kg ai/ha 60 68 92 112 118 T r Glyphosate 1.08kg ai/ha 63 69 87 109 125 T +- Glyphosate 0.72kg ai/ha 55 65 87 107 115 Tj- Glyphosate 0.36kg ai/ha 50 60 81 102 109 Tj- Unweeded control 47 58 78 99 109 LSD (Pa0.05) 6 7 7 8 CV% - 4.5 4.7 3.6 3.9 At the end of the experiment coconut seedlings in the T 3 treatment (Glyphosate at 1.08 kg a.i./ha) were tallest followed by the T 2 (Glyphosate at 1.44 kg a.i./ha) treatment. The highest collar girth increment was found in T 3 (Glyphosate at 1.08 kg a.i./ha) while the second highest increment was found in T 4 (Glyphosate at 0.72 kg a.i./ha) treatment. This indicates that T 2 (Glyphosate at 1.44 kg a.i./ha) treatment is more effective in reducing the weed population with no effect on coconut seedling growth. Some yellow patches also appeared on leaves of seedlings sprayed with 1.44 kg ai/ha (T 2) and 1.08 kg ai/ha glyphosate (T 3). It was noted that manual weeding did not result in any significant increase in growth parameters of the coconut seedlings compared to those in unweeded plots. There were no significant differences between seedlings in control, manual weeded and low concentration of glyphosate used (0.72 kg ai/ha and 0.36 kg ai/ha) plots. The highest growth rate of coconut seedlings was observed in the T 3 treatment (Glyphosate at 1.08 kg ai/ ha) (Tables 1& 2). The rates of seedling height and girth increase were 16.4 cm and 2.2 cm per month respectively in T 3. Cost benefit analysis of different weed control method The costs of different weed control methods are given in the Table 3. Impact of glyphosate on weed biomass and growth of coconut seedlings in nurseries 55 Table 3 : Cost analysis of different weed control treatments. Treatments Frequency of treatment application during the nnrserr period Weeding cost per 1000 coconut seedlings in o n application Total weeding cost per 1000 coconut seedlings during the nursery period Ti-Manual weeding 4 1000.00 4000.00 Tr Glyphosate 1.44kg ai/ha 3 66.00 198.00 T r Glyphosate 1.08kg ai/ha 3 60.00 180.00 T«- Glyphosate 0.72kg ai/ha 3 52.00 156.00 li- Glyphosate 036kg ai/ha 3 44.00 132.00 A v t i i j c pnee of c o m o e r a a l prodacl of fiypbeatic SL R* 400 max A v n g s labor vtgK SL H i 500/ ta iaday US IS . Sri Lankan (SL) IU I U Treatments with glyphosate at 1.44 kg ai/ ha and 1.08 kg ai/ha produced the lowest weed biomass, but the most cost-effective method of controlling weeds in the study was to apply glyphosate at the rate of 1.08 kg ai/ha (3 1 commercial mixture per ha). Manual weeding was the most expensive. The low concentrations of glyphosate treatments such as T 4 and T ; were less expensive but they were not effective in controlling weeds. CONCLUSION Application of glyphosate at 1.08 kg ai/ ha gives the most cost effective weed control method to produce good quality seedlings in coconut nurseries. Lower concentrations did not control weeds effectively in coconut nurseries. REFERNCES Annual Report, (2002). Central Bank of Sri Lanka, 68-70pp. Boyali, L.A. (1979). The control of perennial weeds, In: Recent Adv. in Weed Res. (Ed: W.W. Fletcher), 141-166pp, Surrey, The Gresham Press. Eaton, B.J., Russ and Feltner, K.C. (1976). Competition of velvet leaf, prickly sida and Venice mallow in soybean. Weed Sci. 24:224-228. Gunasekara, T.G.L.G. and Fernando, D.N.S. (1994). Agricultural importance, biology, control and utilization of Cyperus routundus. The Planter, 70: 537-544. Liyanage, L.V.K and Liyanage, M.de S. (1989). Weed control understorey weed management in coconut lands. CORD (1)8: 48-56. Liyanage, D.V. and Abeywardana, V. (1957). Correlation between seed nut, seedling and adult palm characters in coconut. Trop. Agric, CXIII, 325-340. Manipura, W.B. and Somarathne, A. (1974). Some effects of manual and chemical defoliation on the growth and carbohydrate reserves of Panicum repens (L) Beauv. Weed Res, 14: 167-172. Peries , R.R.A. and Everard, J.M.T.D. (1993). River sand as an alternative-to topsoil for 56 Senarathne raising coconut seedlings in polybags. Cocos, 9: 40-46. Pethiyagoda, U. (1980). Handbook on Coconut Cultivation, Colombo, 68-70p, Ceylon Printers Limited. Remison, S.U. and Mgbeze, G.(1987). Competitive effects of weeds and beneficial effects of mulching on coconut seedlings, Cocos 5: 19-28. Statistical Analysis Systems, (1999). S A S 1, STAT Users Guide, Release, 7.00 Cary, NC: Statistical Analysis Systems Institute, p 1028. Suraningtyas, H. (1997). Impact of Imperara cy lindrica on smallholder rubber production, Proc. Brighton Crop Protection Conf. on Weeds. Brighton, United Kingdom, 209-214 Statistical Pocket Book of Plantation Sector. (2002). Ministry of Plantation Industries, 90pp. Wibawa, G. (1997). Study of the component interactions in Hevea based intercropping systems. Internal Report, Sembawa Research station, Palembang, Indonesia, 24pp. 

Impact of Glyphosate on weed biomass and growth of coconut seedlings in nurseries

Abeysekara, A.W.A.D.R.

Subasinghe, S.D.J.N.

An assessment of labour availability in major coconut growing areas in coconut triangle

Ekanayake, G.K.

Perera, S.A.C.N.

Dassanayake, P.N.

Everard, J.M.D.T.

COCOS,2010,19: 41 -50 Printed in Sri Lanka RESEARCH ARTICLE Varietal Classification of New Coconut (Cocos nucifera L.) Forms Identified from Southern Sri Lanka G K Ekanayake75- S A C N Perera', P N Dassanayake', J M D TEverard' 'Coconut Research Institute of Sri Lanka 'University of Sri Jayawardenepura, Sri Lanka 'Current Address: Dhammissara National College, Nattandiya, Sri Lanka Author for correspondence: SA C NPerera Email: chandrikaperera2003@yahoo.com ABSTRACT Coconut in Sri Lanka is currently classified into 15 different coconut forms grouped under three varieties, namely Typica, Nana and Aurantiaca. Several new coconut morphotypes that were not represented in the previous classifications were identified during a recent coconut germplasm exploration mission in the Southern Province of Sri Lanka. The visual morphological features of several new coconut morphotypes (Ran pol, Bothal thembili, Juwan, Murusi, Dothalu and Thatin) were characterized with the objective of including them in the taxonomic classification of coconut in Sri Lanka Stature and breeding behaviour were the main features observed while stem morphology, root bole formation, crown size, nut morphology and bearing patterns, and other specific morphological features were recorded. The data provided morphological evidence to classify Ran pol, Juwan and Rath gon thembili as new forms of variety Typica; Green dwarf 'Murusi', Yellow dwarf 'Murusi' and Brown dwarf 'Murusi' as forms of variety Nana; and Bothal thembili as a new form of variety Aurantiaca. The morphotypes, Thatin and Dothalu were identified as forms of variety Typica but the sample size was too small for confirmation. Key words: coconut, varietal classification, Sri Lanka. INTRODUCTION The classification of coconut has not been adequately standardized, and different authors in different countries use different terminology. Generally, coconut is classified, based on its stature and breeding behaviour, into two broad groups or types: tall (also termed typica) and dwarf (also termed nana). In addition, a few intermediate groups, sometimes referred to as semi-tails or semi-dwarfs have also been recognized. King coconut in Sri Lanka (Liyanage, 1958), Gangabondom in India (Menon and Pandalai, 1958) and Niu Leka Dwarf in Fiji (Powell, 1868; Bourdeix et al. 2005) are examples of such intermediate groups. The first systematic classification of coconut germplasm in Sri Lanka was reported in 1958 42 Ekanayake et. al. (Liyanage, 1958). This classification, based largely on stature and reproductive behaviour of the palm, recognizes three varieties, namely Typica (tall), Nana (dwarf) and Aurantiaca (intermediate). There are several morphotypes in each variety and these were termed as 'forms within varieties'. Liyanage's classification recognizes 13 forms within the three varieties. With the subsequent additions made by ^Wickremarame (1984) and Perera et al. (1997) 15 coconut forms have been recognized within the three varieties in Sri Lanka (Table 1). Variety Typica Nar. (tall) is the most abundant coconut variety in Sri Lanka and most coconut growing countries. It is tall in stature and naturally outbreeding. Typica forms usually take 5-6 years to flower and they produce flowers continuously. They are hardy palms that tolerate a wide range of environmental conditions. Typica, Navasi, Gon-thembili, Ran-thembili, Pora-pol, Bodiri, Kamandala and Dikiri are the different forms of the variety Typica (Table 1). The form Typica (Sri Lanka Tall), is grown on a commercial scale for production of endosperm, shell and fibre products. The other forms are found scattered in small numbers, mainly in home gardens. They are of little economic significance other than as candidates for breeding improved varieties. Variety Nana (Griff) Nar. (dwarf) is short in stature and naturally inbreeding. It flowers early in about 3-4 years from planting and is a seasonal bearer. Nana forms suffer adversely from drought, pests and diseases. Dwarf coconuts are not grown on a plantation scale but are extensively used in the production of coconut hybrids because of their short stature, precocity and profuse bearing ability. Green dwarf (pumila), yellow dwarf (eburnea,), red dwarf (regia) and brown dwarf braune (Perera et al. 1997) are the forms of the variety Nana (Table 1). Variety Aurantiaca Liy., which includes king coconut and similar forms, is intermediate in stature, predominantly inbreeding and late flowering. Flower production, which commences about 5 to 6 years after planting, is seasonal. The low tolerance to drought, pests and diseases restricts the areas in which king coconuts thrive. Tender king coconut, with its bright orange epicarp, and high sucrose, sweet nut water, is a very popular beverage coconut. Variety Aurantiaca has three forms, namely king coconut (thembili), rathran thembili and navasi-thembili (Table i). Genetic variation in the germplasm pool provides material for crop improvement. Much of the diversity of coconut forms hitherto identified in Sri Lanka has already been extensively tested in breeding programmes. However, there is a need for more germplasm with diverse characteristics to meet the requirements of the coconut breeding programme. A survey, in the Southern Province of Sri Lanka, to explore new germplasm to enrich the Coconut Research Institute germplasm collection (Everard et al. 2004), identified several new coconut phenotypes that merit detailed morphological assessment (Ekanayake et al. 2007). The aim of the current study was to morphologically differentiate the new forms identified in the Southern Province, and accordingly classify them under varieties. Varietal Classification of New Coconut (Cocoa nucifera L.) Forms Identified From Southern Sri Lanka 43 Table I: Varieties and forms of coconut found in Sri Lanka Common name (Variety/form) Specific morphological and reproductive features Sri Lanka Tall (TypicalTypica) Tall stature, allogamous, heterogeneous, flowers in 6 —7 years, medium sized nuts, 20-25 nuts per bunch, 60-80 nuts per palm per year Gon Thembili (Typica/Gon thembili) Similar to Sri Lanka Tall. Ivory coloured nuts, petioles and inflorescences Nawasi (Typica/Nawasf) Similar to Sri Lanka Tall. Soft mesocarp - edible in the immature nut yields soft fibre when mature. Pora Pol (Typica/Pora pot) Similar to Sri Lanka Tall. Remarkably thick shelled nuts Ran Thembili (TypicalRan thembili) Similar to Sri Lanka Tall. Pink coloured mesocarp in immature fruit and a pink whorl under the perianth. Large nuts. Kamandala (Typica/Kamandala) Similar to Sri Lanka Tall. Large sized nuts (largest among local forms), and few nuts per bunch (2-5 nuts per bunch). Bodiri (Jypiai/Bodiri) Similar to Sri Lanka Tall. Small sized nuts and large number per bunch (30-100 nuts per bunch). Seasonal nut production. Dikiri (Typica/Difan) Similar to Sri Lanka Tall. Some nuts contain a jelly-like albumen/endosperm. King Coconut (Aurantiaca/King coconut) Intermediate stature, autogamous, homogeneous, fruits in 6-7 years, seasonal flower production, medium sized nuts with orange epicarp and sweet nut water, 25-50 nuts per bunch. Nawasi Thembili (Aurantiaca/Nawasi thembili) Similar to King Coconut. Soft and edible mesocarp like Nawasi Rathran thembili (Aurantiaca/'Rathran thembili) Similar to King Coconut. Pink coloured mesocarp and a pink whorl under the perianth. Green dwarf (Nana/Green dwarf or pumila) Dwarf stature, autogamous, homogeneous, fruits in 3-4 years, small sized nuts with green epicarp. low copra content, 80-150 nuts per palm per year Yellow dwarf (Nana/FeZ/ow dwarf or ebumea) Similar to Green dwarf. Nuts with yellow epicarp. Red dwarf (Nana/Red dwarf or regia) Similar to Green dwarf. Nuts with red epicarp. Brown dwarf (Nana/flrown dwarfor braune) Similar to Green dwarf. Nuts with a brown epicarp. M A T E R I A L S A N D M E T H O D S A survey was conducted in Galle area (Coordinates 603'0"N 80013 '0"E) (Figure 01) in the Southern Province of Sri Lanka. The surveyed lands were home gardens and small holdings where the traditional coconut varieties are planted, rather than the plantations where the commercial cultivars are grown. Much of the information regarding the different phenotypes and their locations were received from the coconut pickers in the area. Six new morphotypes of coconut, identified 'in the survey, by their vernacular names, Ran pol, Bothal thembili, Juwan, Murusi, Dothalu 44 Ekanayake el. al. Table 2: Morphological characters and the traits scored for characterizing coconut morphotypes Character Traits scored Stem morphology stature (tall/dwarf) presence/absence of bole Crown morphology crown size (well spread/small) Fruit morphology fruit colour fruit shape fruit size Breeding behaviour self/cross pollinating nature seasonality Yield prolificacy and Thatin were assessed by studying the morphological parameters of the stem, crown and fruit, their reproductive and bearing behaviour as well as other specific morphological features. All these morphotypes were found in a few villages clustered around Unawatuna in Galle District of the Southern Province of Sri Lanka. Samples of 7 -10 palms each of Ran pol, Bothal thembili, Juwan and Murusi were assessed but only two palms of Thatin and one palm of Dothalu were available for this sludy. The morphological traits were scored over a period of 3 years to observe the temporal variation of the traits in each phenotype. Apart from the morphological traits specified in Table 2, other visually observable specific features of the new morphotypes were also recorded. RESULTS A N D D I S C U S S I O N Grouping the new phenorypes under coconut varieties The main morphological features used to group coconuts are the stature and breeding behaviour. In addition, the presence or absence of a bole, shape of the crown and regularity of bearing were taken into consideration. These features of the varieties Typica, Nana and Aurantiaca, and of the newly identified coconut morphotypes are presented in Table 3. Some features of the new morphotypes are illustrated in Figures 1-9. Varietal Classification of New Coconut (Cocos nucifera L.) Forms Identified From Southern Sri Lanka 45 9 9 I I H i 1 Figure I: Ran pol crowns and nuts Figure 3: Juwan coconuts ll'feif Figure 5: Thatin coconut Figure 4: Murusi (Green) Figure 6: Dothalu coconut 46 Ekanayake et. al. Figure 9: Brown murusi Varietal Classification of New Coconut (Cocos nucifera L.) Forms Identified From Southern Sri Lanka 47 Table 3: Basic morphological descriptors utilized in coconut varietal classification in Sri Lanka and the corresponding features of the seven newly identified coconut morphotypes Variety/ Morphotype Stature Breeding behaviour Root bole Crown Bearing habit Typica tall cross pollinating present well spread year-round Nana dwarf self pollinating absent small intermittent Aurantiaca intermediate self pollinating present medium intermittent Ran pol tall cross pollinating present well spread year-round Bothal thembili intermediate self pollinating present medium intermittent Juwan tall cross pollinating present well spread year-round Murusi (green, yellow and brown) dwarf self pollinating absent small intermittent RathGon thembili tall cross pollinating present well spread . year-round Thatin tall cross pollinating present well spread year-round Dothalu tall cross pollinating present well spread intermittent The variety Typica essentially comprises tall and predominantly cross pollinating coconut palms. The data presented in Table 3 suggest that Ran pol, Juwan, Thatin, Dothalu and Rath Gon thembili can be grouped under variety Typica. Presence of a root bole is yet another prominent morphological feature defining tall coconuts and all root boles. Furthermore, these phenotypes exhibit well spread crowns and a year-round bearing pattern, which are also features characteristic of Typica. In regard to Thatin and Dothalu, as the sample size in the current study was inadequate, their grouping needs to be confirmed by studying more palms or by studying the selfed progeny of me above mentioned phenotypes display prominent the 2 morphotypes. 48 Bolhal thembili, with its intermediate stature, self pollinating breeding behaviour and the orange coloured fruit epicarp can be included in the variety Aurantiaca, which includes all king coconut types in Sri Lanka. The medium sized crown and intermittent nut production provide further evidence for this classification. The dwarf stature, predominantly self breeding nature, absence of a root bole, relatively small crown and the seasonal nut production provide evidence for considering Murusi as a Nana (dwarf) variety. Classification of the new coconut phenotypes as forms within varieties Distinct morphological features are used to classify different forms within a variety. The Ekanayake et. al. different forms within a variety possess the basic requirements to be included under that particular variety. In addition, each form has unique morphological features to distinguish it from all the other forms. Fruit colour, fruit size, fruit shape, petiole colour, mesocarp or endocarp softness and thickness, and the prolificacy of nut production are examples of traits used to distinguish forms within varieties. Table 4 presents the specific morphological features of the new coconut phenotypes, identified from Southern Sri Lanka, which enable them to be regarded as forms within the three main varieties of coconut in Sri Lanka. Consequently, the new forms listed in Table 4 are not only different from each other, but also different from the forms identified by Liyanage (1958), Wickremaratne (1984) and Perera et al. (1997). Table 4: Specific morphological features of the new coconut types identified in Southern Sri Lanka and their classification as forms within varieties Vernacular name Specific morphological features (^Variety/form) Ran pol (Typica/Ran pot) Tall palms with stout fast growing stems. Very large round coconuts of mostly brown or less commonly green fruits. Plicata leaves (attached leaflets, especially in young fronds) Bothal thembili Intermediate palms producing orange, elongated coconuts of (Aurantiaca/Sof/ia/ unique shape. thembili) Juwan pol CTypicaJJuwan) Tall palms producing round small nuts. A high number (10-20) nuts per bunch. Murusi (Green) Dwarf palms producing green small coconuts which are rounder (None/Green 'Murusi") in shape than green dwarf nuts. Seasonal nut production. Murusi (Yellow) Dwarf palms producing yellow small coconuts which are rounder (Naaa/Yetlow Murusi"} in shape than yellow dwarf nuts. Intermittent nut production. Murusi (Brown) Dwarf palms producing brown coloured small coconuts which are (Nana/Brown 'Murusi') rounder than brown dwarf nuts. Seasonal nut production. RathCon Thembili Tall palms bearing orange coconuts. The petiole fronds and the CTypica/Rath Gon inflorescences also are of the same colour. thembili) Thatin CTypica/Thatin)* Tall palms producing elongated small coconuts with thick kernels and thin husks. Dothalu Tall palms producing green small elongated coconuts. A targe CTypica/Dothalu)* number of nuts per bunch (20-40) Very sweet nut water. Seasonal ' nut production. * Sample size was inadequate to classify precisely 49 Varietal Classification of New Coconut (Cocos nucifera L.) Forms Identified From Southern Sri Lanka Table 5: Comparison of the nut size and kernel weight of the dwarf and Murusi forms Phenotype '•• Nut size (polar circumference cm) Kernel (g/nut) Green Murusi (54.1) 239.3 Green dwarf (49.8) 135.8 Brown Murusi (56.0) 210.6 Brown dwarf (47.2) 185.7 Yellow Murusi (53.9) 221.0 Yellow dwarf (64.0) 272.3 The green, yellow and brown phenotypes of 'Murusi' are classified within the relevant colour form of variety Nana (Table 4). This differentiation between Murusi and the relevant colour form of dwarf is mainly based on the differences in nut size and kernel weights of the dwarf and Murusi forms (Table 5). As shown in Table 5, Green and Brown Murusi produces larger and heavier nuts than the relevant dwarf forms while Yellow Murusi produces smaller and lighter nuts than Yellow dwarf. Many of the forms of coconut identified earlier (Kamandala, Bodiri, Pora pol, Dikiri etc.) were also naturally distributed in the Southern Province of Sri Lanka and testifies to the rich morphological diversity of coconuts in the area. The local community identifies the new coconut phenotypes by their vernacular names indicating that they have been grown or found naturally in the area over a long period of time and are not freaks or recent mutants. However, these traditional coconuts are endangered due to ongoing urbanization and coconut replanting programmes. Recognizing these coconut phenotypes as forms and their inclusion in the classification will draw attention to the possible existence of more traditional coconut phenotypes in Sri Lanka and the need for their conservation as germplasm accessions. These diverse materials are likely to carry valuable genes for exploitation in future coconut hybridization programmes for diverse uses in addition to being used directly for commercial purposes such as beverage coconuts and daily culinary requirements. A C K N O W L E D G E M E N T S The authors thank Dr. L. Perera, Head of the Genetics & Plant Breeding Division of the Coconut Research Institute of Sri Lanka for his constructive comments on the research and the manuscript. We gratefully acknowledge the financial assistance received from the Coconut Genetic Resources Network for the initial survey to identify farmers' varieties and from the Sri Lanka Coconut CESS Fund for the characterization and conservation of Southern Coconut germplasm. 50 Ekanayake REFERENCES Bourdeix, R. Santos, G. Labouisse, J. R and Baudouin, L. (2005). Useful definition of terms and nomenclature, In: Coconut Genetic Resources, P. Batugal, V. Ramanatha Rao and Jeffrey Oliver, ed., IPGRI, Rome, pp 9-10 Ekanayake, G. K., Perera, S. A. C. N., Dassanayake, P. N. and Everard, J. M. D. T. (2007). Identification, characterization and conservation of new coconut phenotypes from Southern Sri Lanka. Proc. 12 t h Forestry and Environment Symp 2007. pp 76-77 Everard, J. M. D. T. (2004). Report of the Genetics and Plant Breeding Division, Coconut Research Institute, Sri Lanka. 73-77. Harries, H.C. (1978). The evolution, dissemination and classification of Cocos nucifera L. Bot. Rev., 44: 205-317 Liyanage D. V. (1958). Varieties and forms of the coconut palm grown in Ceylon. Ceylon Coconut Quart., 9:1-10 Manthriratna M. A. P. (1972). The performance of dwarfs (Cocos nucifera L. variety nana) as a plantation crop in Ceylon. Ceylon Coconut Quart., 23:92-99 Menon, K P V. and Pandalai, K M. (1958). The coconut, A Monograph, Indian Central Coconut Committee, pp 86-102 Perera, L. Peries, R R A. (1997). Brown dwarf: a recent addition to the varieties and forms of coconut palm grown in Sri Lanka. Cocos 12: 82-84. Powell, T. (1868) On various Samoan plants and their vernacular names. Journal of Botany (London) 6: 278-285, 242-347^ 255-370, Cited in Harries, H C. (1978). The evolution dissemination and classification of Cocos nucifera L., Bot. Rev., 44: 205-317 Wickremaratne, M. R. T. (1984). Report of the Genetics and Plant Breeding Division, Coconut Research Institute, Sri Lanka. 45. 

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