Hypsipyla Shoot Borers of Meliaceae in Sri Lanka - Australian ...

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Table 2. Foreign companies logging in Solomon Islands and their annual quotas in 1996. Company Annual quota (m 3 ) Kalena Timber 160 000 Allardyce Lumber 42 000 Dalsol Ltd 30 000 Pacific Timber 50 000 Hyundai 75 000 Intergrated Forest Industry 72 000 Kayuken Pacific 50 000 Eagon Forest Development 93 000 Levers Solomon 40 000 Marvin Brothers 30 000 TOTAL 642 000 Government planting on logged-over crown land started in 1967 and through till 1996, about 26 000 ha had been planted to various indigenous and exotic species. Initially, enrichment planting was the dominant method. Planting material was then mostly from wildings of major commercial indigenous species (e.g. Terminalia brassii Exell, Campnosperma brevipetiolata Volk., Eucalyptus deglupta Bl.) and Swietenia macrophylla Jacq. imported from Papua New Guinea and Fiji. Currently, six major tree species are recommended for large-scale plantations in Solomon Islands. Table 3 lists these species and gives their recommended espacement. Table 3. Tree species and espacement recommended for plantation forestry in Solomon Islands. Species Espacement Cedrela odorata L. 5 m × 3 m Eucalyptus deglupta Bl. 5 m × 3 m Gmelina arborea Roxb. 4 m × 3 m Swietenia macrophylla Jacq. 10 m × 3 m Tectona grandis Linn. f. 4 m × 3 m Terminalia brassii Exell 5 m × 3 m Following the Government Structural Adjustment Policy on Privatisation in 1995, all government plantation establishment ceased. Large scale forestry planting is now done by private companies only. The net planted area from 1967–1995 is as shown in Table 4. Economic Importance and Success of Swieteniodeae Species The only indigenous species belonging to the subfamily Swietenioideae of the family Meliaceae in Solomon Islands is Xylocarpus granatum Koen. This is a mangrove species and of little commercial value. 38 Fruit of X. granatum has been destroyed by feeding of larvae of Hypsipyla robusta (Moore) (Bigger 1988) while shoot feeding has not been recorded. Two exotic high-value species of Swietenioideae, Cedrela odorata L. and Swietenia macrophylla Jacq., have been grown in Solomon Islands and are among the most important plantation species in Solomon Islands. C. odorata is minimally attacked by H. robusta while S. macrophylla is generally heavily attacked (Bigger 1988). S. macrophylla has been widely planted in Solomon Islands and by the end of 1995 the Forestry Division has planted 3545.5 ha. Hypsipyla robusta Research and Future Directions Hypsipyla robusta is a major pest of species in the Swietenioideae which includes Swietenia spp. and Cedrela spp. H. robusta is found in the South Pacifc in Australia, Papua New Guinea and Solomon Islands but does not extend to Vanuatu or Fiji (Bigger 1988). Early specimens from Solomon Islands were identified at the British Museum of Natural History as Hypsipyla pagodella Ragonot in 1969 while specimens in 1970 were identified at the Commonwealth Institute of Entomology as H. robusta. H. pagodella is a junior synonym of H. robusta (Horak, these Proceedings). The presence of shoot borer is quite noticeable as the shoot tips above the larval entrance hole rapidly die and turn black. The presence of larvae is also indicated by quantities of frass ejected from the entrance holes. In other countries, it has been reported that H. robusta attacks leaves, flowers and shoots (Bigger 1988). In plantations of S. macrophylla in Solomon Islands, the only parts of trees that have been observed to be attacked are the shoots of young plants (Wilson 1986a). The first reported attack of H. robusta in Solomon Islands was in 1959 when the Mt Austen trial plot of Toona ciliata M. Roem. was virtually destroyed and S. macrophylla was also severely distorted. The most serious pest of S. macrophylla in nurseries is H. robusta, on occasions affecting a high proportion of seedlings (Wilson 1986b). The seedlings usually survive but develop multiple shoots, making them not acceptable material for planting. An insecticide that can be used to effectively control H. robusta in nurseries is the systemic insecticide, Orthene, which was applied to foliage using a knapsack sprayer. Chemical application in the field is not recommended as it is too expensive and the whole operation would be uneconomical. A nursery trial has been established to determine if attack of H. robusta can be reduced by randomly
mixing seedlings of S. macrophylla, C. odorata and Tectona grandis Linn. f. After 2 months, no attack was noted on any of the seedlings. It is still too early to conclude whether shoot borer damage has been reduced. Field experience indicates that closely spaced S. macrophylla are highly susceptible to H. robusta and wide spacing leads to invasion of the crown of the trees by the climbing vine, Merremia peltata (L.) Merr. The current recommendation is spacing at 10 m × 3 m since damage from H. robusta was considered a greater risk than competition from M. peltata. A nurse crop was considered to be a better strategy to overcoming both these problems. A plantation of alternate rows of S. macrophylla and Terminalia calamansanai (Blco.) Rolfe was established in 1984. This trial was not successful due to different growth rates leading to different Table 4. Net area of plantation established in Solomon Islands from 1967 to 1995. 39 harvesting time and the S. macrophylla being suppressed by the fast growing T. calamansanai. Another mixed species trial was established using S. macrophylla and Schleinitschia novo-guinensis (Schn). Again in this trial, the nurse species grew faster and suppressed the S. macrophylla. Another nurse crop trial has been established with a different nurse crop species (Securinega flexuosa (Muell. Arg.)). The data from the trial had not yet been analysed but it appeared that there was a difference in both growth and H. robusta attack when line planted S. macrophylla are compared with those planted under a nurse crop. There is also some indication that small black birds while feeding on S. flexuosa fruit may also feed on H. robusta larva on the mahogany. This idea is yet to be experimentally tested. Year Area planted (ha) for each tree species Total Area AGAM CAMB CEDO EUCD GMEA SWIM TECG TERB TERCAL MINOR (ha) 1967 47.0 47.0 1968 173.7 173.7 1969 279.2 279.2 1970 177.7 55.0 232.7 1971 498.3 442.4 940.7 1972 543.1 394.2 937.3 1973 75.7 14.9 39.6 130.2 1974 778.9 265.0 92.0 297.6 1433.5 1975 721.8 159.5 881.3 1976 1045.4 69.0 69.0 212.3 1395.7 1977 128.4 688.0 468.6 217.3 27.0 1529.3 1978 528.9 1733.8 827.9 58.0 285.3 3433.9 1979 583.7 1416.2 400.5 70.0 28.8 258.6 2757.8 1980 66.5 281.0 133.8 774.9 388.9 1645.1 1981 72.6 36.5 15.3 74.3 198.7 1982 18.1 223.1 64.9 175.8 26.0 7.0 514.9 1983 129.3 192.3 65.5 395.5 88.7 55.5 87.3 1014.1 1984 175.4 66.2 384.3 18.2 92.9 133.4 47.8 918.2 1985 140.4 193.5 100.7 460.1 50.9 166.9 34.1 81.1 1227.7 1986 36.5 119.9 45.6 62.0 198.4 86.5 232.1 160.2 16.6 957.8 1987 31.6 70.1 184.5 445.9 137.5 250.4 1120.0 1988 106.5 15.0 357.0 359.0 173.9 26.4 1037.8 1989 209.8 230.4 518.4 358.1 1316.7 1990 56.3 319.5 65.1 160.2 30.1 631.2 1991 21.6 71.4 23.9 116.9 1992 0.0 1993 4.2 211.3 40.3 52.3 308.1 1994 91.1 286.3 202.9 115.2 695.5 1995 95.0 285.8 147.9 57.7 586.4 Total 1527.5 9295.6 897.9 1961.5 2389.8 3545.5 1210.5 2357.7 2738.0 537.4 26 461.4 ACAM – Acacia mangium Willd.; CAMB – Campnosperma brevipetiolata Volk.; CEDO – Cedrela odorata L.; EUCD – Eucalyptus deglupta Bl.; GMEA – Gmelina arborea Roxb.; SWIM – Swietenia macrophylla Jacq.; TECG – Tectona grandis Linn. f.; TERB – Terminalia brassii Exell; TERCAL – Terminalia calamansanai (Blco.) Rolfe
Page 1 and 2: Hypsipyla Shoot Borers of Meliaceae
Page 3 and 4: Mayhew and Newton (1998) have revie
Page 7 and 8: Table 1. Summary of current and pas
Page 9 and 10: 26° 21° WEST BENGAL (INDIA) PACHA
Page 11 and 12: The only harvesting of Swietenioide
Page 15 and 16: H. robusta. From that time onwards,
Page 17 and 18: successful and is expected to have
Page 19 and 20: them are species of the subfamily S
Page 21 and 22: T. ciliata grows in dry deciduous f
Page 23 and 24: Table 1. Area of forestry plantatio
Page 25 and 26: S. macrophylla and Swietenia mahago
Page 27 and 28: plantings of S. macrophylla, K. sen
Page 33 and 34: Table 1. Major plantation areas and
Page 35: Hypsipyla Shoot Borers of Meliaceae
Page 41 and 42: of these species, plantings have be
Page 43 and 44: 45 Table 5. Continued. Description
Page 45 and 46: 47 Table 6. Description of on-going
Page 47 and 48: locations were generally poorer, wi
Page 51 and 52: growth response and resultant form
Page 53 and 54: Mr David Spolc (University of Queen
Page 55 and 56: Haley, C. 1954. Forestry in Tropica
Page 57 and 58: Gross Domestic Product, a contribut
Page 59 and 60: A number of parasitoids have been b
Page 61 and 62: A Review of Hypsipyla grandella Zel

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