TOKSISITAS (LC50 dan LT50) JAMUR ENTOMOPATOGEN Beauveria bassiana (Bals.) Vuill. TERHADAP HAMA ULAT GRAYAK (Spodoptera litura F.)

Toxicity of enthomopathogenic fungi Beauveria bassiana to armyworm (Spodoptera litura) has been investigated in Pest Laboratory of Faculty of Agriculture, Syiah Kuala University, Darussalam, Banda Aceh. This research was aimed at determining lethal concentration (LC50) and lethal time (LT50) of B. bassiana suspensions against third instar larvae of armyworm. The fungi concentration used was in the range 0-6 % (w/v) or equal to 9,33 x 106 – 45,83 x 106 conidia/ml. The fungi suspension was applied to the larvae by dissolving the larvae into the suspension for 10 seconds. The number of the larvae died and the time required to kill the larvae were recorded everyday starting one day after application (DAA) until pupation. The relation between each observation to the fungi concentration was analyzed using probit analysis. The result showed that B. bassiana suspension caused the death of the larvae beginning 4 DAA with maximum eath on 10 DAA. The death of the larvae caused by the growth and the development of the fungi inside the larvae. The LC50 of the fungi suspension against the larvae was 3,57 % while the LT50 at 4, 5, and 6 % fungi concentration were 9,88; 8,13; and 6,8 days respectively

Fig trees and fig wasps: their interactions with non-mutualists

Non-mutualist species that interact with mutualists occur commonly in nature. Non-mutualists associated with the mutualism between fig trees and their pollinating fig wasps include mites and nematodes. This thesis focusses on the interaction of nematodes with fig trees and fig wasps in South Africa and Indonesia, with additional investigation on how mites, nematodes and fig pollination respond to highly seasonal environments. The reproduction of monoecious Ficus burtt-davyi in Grahamstown, South Africa slows down but does not stop in winter. There are fewer fig pollinating wasps Elisabethiella baijnathi flying in the air during winter, but most figs are probably pollinated by locally-produced fig wasps. Elisabethiella g5baijnathi females transport mites (Tarsonemella sp. nr. africanus) and nematodes (Parasitodiplogaster sp.) between figs. Contrasting dispersion patterns and relationships with fig wasp foundress numbers indicate that the mites, but not the nematodes, disperse between figs after being carried there by the pollinators. Three nematode species (Caenorhabditis sp., Schistonchus centerae, and S. guangzhouensis) developed inside both male and female figs of dioecious F. hispida tree in Sumatra, Indonesia. Caenorhabditis sp. was transferred between figs as juveniles, whereas Schistonchus spp. were transferred mostly as juveniles, and occasionally as adults. The nematode community of eight species in Sumatran monoecious F.racemosa was the most diverse recorded anywhere. No mites were found in both species of fig trees. Peak nematode populations occurred in D-phase figs, when the fig wasp offspring are ready to emerge. The nematodes attach themselves to newly-emerged female pollinators, which then carry them away. Usually more nematodes attached on the first fig wasps to emerge. Entry into figs by early-emerging pollinators resulted in higher numbers of the next generations of nematodes within the figs. Details of the ecology of each nematode species may be different, but as a group they did not seem to significantly affect seed and wasp development in both F. hispida and F. racemosa figs

Fig Pollinating Wasp Transfers Nematodes into Figs of Ficus racemosa in Sumatra, Indonesia

The fruits (figs) of fig trees (Ficus spp, known as ‘bak ara’ in Aceh), are the source of food for many species of faunas in the forest, including birds, monkeys, orangutans, etc.  Pollination within the figs totally depends on female fig wasps that belong to family Agaonidae. Fig trees and their pollinating wasps rely on each other to survive.  Female fig wasps are known to transport nematodes into receptive figs when the wasps enter the figs to lay  eggs.  An investigation on the nematodes carried by female pollinating wasps Ceratosolen fusciceps Mayr into figs of Ficus racemosa was conducted in Sumatra, Indonesia. The figs on the trees were regularly sampled to determine the presence of nematodes and infer their ecology. The Baermann funnel method was employed to extract the nematodes from the figs.  Eight species of nematodes were recorded from the figs, two of which are still unidentified.  The species found were (1) Teratodiplogaster fignewmani, (2) Teratodiplogaster sp., (3) Parasitodiplogaster sp., (4) Schistonchus sp1., (5) Schistonchus sp2., (6) Mononchoides sp., (7) and (8) two undescribed Diplogastridae species (‘umbrella-like’ species 1 and species 2).  This is the most diverse fig nematode community recorded. The highest nematode populations were routinely found in D-phase figs, when the new generations of wasps were about to emerge.   Details of the ecology of each nematode species are likely to differ, but as a group they did not seem to significantly affect seed and wasp development in F. racemosa fig

The Level of Coffee Berry Borer (Hypothenemus hampei Ferrari, 1867) Attack on Organic and Conventional Arabica Coffee Plantations at Several Altitudes

This study was conducted to investigate the influence of elevation and the cultivation system of Arabica coffee against the attack of the coffee berry borer (Hypothenemus hampei Ferrari, 1867) in Arabica coffee plantations in Central Aceh District, Aceh Province, Indonesia. We observed the attack level of H. hampei on Arabica coffee plants that were cultivated both organically and conventionally. Those were planted at three different altitudes, namely: 900- 1,100 m; 1,100-1,300 m and 1,300-1,500 m above sea level. The results showed that the attack level of coffee berry borer (CBB) on organic coffee plantations was lower than on conventional ones in general. The attack level of CBB on organic and conventional coffee plantations for 5 observations was between 16.9 - 26.1% and 23.4 - 33.6%, respectively. The results also showed that the attack level of CBB was influenced by the altitude of the coffee cultivation. At an altitude of 1,300-1,500 m, the attack level of CBB ranged from 11 to 17%, and this was much lower than at altitudes below 1,300 m. Meanwhile, at an altitude of 900-1,100 m and 1,100- 1,300 m, the attack level by this pest was around 27-40%. The results of this study indicated that both cultivation systems (organic and conventional) and altitudes of coffee plantation greatly influenced the attack level by CBB. Altitude is directly related to the temperature, while the cultivation systems are thought to have an effect on the level of presence and the role of natural enemies in suppressing CBB pest populations. Therefore, it is recommended to cultivate Arabica coffee organically, especially on the land at an altitude between 900-1300 m to reduce the attack level by CBB

Re-Deskripsi Leucopitermes Leucops; Subulitermes-Group (Isoptera, Termitidae, Nasutitermitinae) Di Stasiun Penelitian Suaq Balimbing, Aceh Selatan

Leucopitermes leucops merupakan spesies rayap yang dimasukkan kedalam kelompok soil-feeding nasute atau Subulitermes-group yaitu spesies rayap pemakan material “tanah”. Rayap ini memiliki peran penting dalam proses dekomposisi material organik tanah. Taksonomi rayap Subulitermes-group selama ini masih sulit dipahami dan mengalami sejumlah revisi. Penelitian ini bertujuan untuk mendeskripsikan kembali rayap Leucopitermes leucops di Stasiun Penelitian Suaq Balimbing, Taman Nasional Gunung Leuser. Penelitian ini menggunakan metode belt-transek. Hasil penelitian berdasarkan deskripsi karakter morfologi Leucoptermes leucops menunjukkan bahwa karakter kapsul kepala pada kasta prajurit dan mandibel pada kasta pekerja menjadi karakter kunci untuk membedakan Leucopitermes leucops dengan spesies dari genus yang sama maupun dengan spesies Subulitermes-group lainnya.Leucopitermes leucops is a termite species of soil feeding-nasute or Subulitermes-groups its classification by "soil" feeders. This termite has an important role in the decomposition process of soil organic matter. Currently, the taxonomy of this group is still difficult to understand and experience a number of revisions. This study aims to re-describe of Leucopitermes leucops in Suaq Balimbing Research Station. The method used was a standardized sampling protocol (belt transect) method. The result was described based on morphological characters of Leucopitermes leucops it is found that the key characters to distinguish Leucopitermes leucops with species in the same genus and other Subulitermes-group species

The Level of Coffee Berry Borer (Hypothenemus hampei Ferrari, 1867) Attack on Organic and Conventional Arabica Coffee Plantations at Several Altitudes

This study was conducted to investigate the influence of elevation and the cultivation system of Arabica coffee against the attack of the coffee berry borer (Hypothenemus hampei Ferrari, 1867) in Arabica coffee plantations in Central Aceh District, Aceh Province, Indonesia. We observed the attack level of H. hampei on Arabica coffee plants that were cultivated both organically and conventionally. Those were planted at three different altitudes, namely: 900- 1,100 m; 1,100-1,300 m and 1,300-1,500 m above sea level. The results showed that the attack level of coffee berry borer (CBB) on organic coffee plantations was lower than on conventional ones in general. The attack level of CBB on organic and conventional coffee plantations for 5 observations was between 16.9 - 26.1% and 23.4 - 33.6%, respectively. The results also showed that the attack level of CBB was influenced by the altitude of the coffee cultivation. At an altitude of 1,300-1,500 m, the attack level of CBB ranged from 11 to 17%, and this was much lower than at altitudes below 1,300 m. Meanwhile, at an altitude of 900-1,100 m and 1,100- 1,300 m, the attack level by this pest was around 27-40%. The results of this study indicated that both cultivation systems (organic and conventional) and altitudes of coffee plantation greatly influenced the attack level by CBB. Altitude is directly related to the temperature, while the cultivation systems are thought to have an effect on the level of presence and the role of natural enemies in suppressing CBB pest populations. Therefore, it is recommended to cultivate Arabica coffee organically, especially on the land at an altitude between 900-1300 m to reduce the attack level by CBB

UJI TEPUNG DAUN JARAK PAGAR (JATROPHA CURCAS L.) UNTUK MENGENDALIKAN NEMATODA PURU AKAR (MELOIDOGYNE SPP.) PADA TANAMAN TOMAT

Meloidogyne spp. merupakan salah satu patogen penting pada tanaman tomat. Hasil penelitian sebelumnya menjelaskan bahwa Jatropha curcas memiliki bahan aktif sebagai nematisida. Dalam pnelitian ini menggunakan daun J. curcas dalam bentuk bubuk untuk mengendalikan pathogen. Penelitian ini bertujuan untuk menguji beberapa dosis serbuk daun J. curcas (0; 1,5; 2,5; 3,5; 4,5 g/kg tanah) untuk mengendalikan Meloidogyne spp. Nematisida diaplikasikan pada lingkungan rizosfer tanaman secara artifisial. Pengamatan meliputi masa inkubasi, presentase tanaman terserang, jumlah puru yang terdapat pada akar dan populasi nematode. Hasil penelitian menunjukkan bahwa serbuk daun J. curcas pada 3,5 g/kg tanah memperpanjang masa inkubasi, menekan intensitas penyakit, menurunkan jumlah puru dan populasi Meloidogyne spp  masing-masing higga 60%, 62%, 87% dan 54%. Berdasarkan hasil penelitian tersebut menunjukkan bahwa serbuk daun J. curcas mampu mengendalikan Meloidogyne spp. pada tanaman tomat.Jathropa (Jatropha curcas L.) Leaf Powder Test to Control Root-knot Nematodes (Meloidogyne spp.) on Tomato Plants Meloidogyne spp. is one of important pathogen on tomato. Previous reports show that Jatropha. curcas has active ingridiens as nematicide. In this research we employ J. curcas leaves in powder form to control the pathogen. The aim of this study is to examine several dosages of J. curcas leaves powder (0; 1,5; 2,5; 3,5; 4,5 g/kg of soil) to control Meloidogyne spp. The nematicide was applied on the rhizosphere of the plant artificially. The observation was including incubation time, percentage of affected plant, number of galls, and nematode population. The results show that J. curcas leaves powder at 3.5 g/kg of soil prolongs the incubation time, suppress disease intensity, decrease the number of galls and Meloidogyne spp. population up to 60%, 62%, 87% and 54%, respectively. The results indicate that J. curcas leaves powder capable of controlling Meloidogyne spp. on tomato plant

Effect of host diets on host preference and host suitability in Telenomus parasitoid (Hymenoptera: Scelionidae)

Telenomus sp. is one of the most important biological control agents for several Hemipterous and Lepidopterous  insects.  This study was performed to determine the effect of host diets on host preference and host suitability in Telenomus parasitoid.    In this research, the hosts (Nezara viridula) was reared on the different diets, i.e. Vigna sinensis, Phaseolus vulgaris, and Indigofera suffruticosa.  The result of this experiment showed that the parasitization level of Telenomus sp was not affected by host diets.  However, host diets affected on the percentage of the parasitoid offspring. The percentage offspring was 96%, 81% and 44% from host fed on I. suffruticosa, V. sinensis,and P. vulgaris, respectively. The offspring for all of treatments was biased to female (more than 70%), however it was not affected by host diets. The developmental time for immature stage of Telenomus was also affected by host diets, it was 12, 13 dan 14 days from host fed on I. suffruticosa, V. sinensis,and P. vulgaris, respectively.  These results indicated that I. suffruticosa more suitable host diet for the development of  Telenomus progeny, which may due to more riches nutrients contain in this plant than the other plants.

PENGARUH SUPERPARASITISME TERHADAP PERKEMBANGAN PROGENI PARASITOID Tetrastichus brontispae Ferriere

            The purpose of this research was to investigate effects of superparasitism rate on development of Tetrastichus brontispae progeny. In this research, each host (Brontispa longissima pupa) was exposed for different frequencies, i.e., 1, 3, 5, 7 and 9 times for female parasitoid.  The result showed that the rate of superparasitism affected the number of progeny emergence, the developmental time of immature progeny, and sex ratio of progeny. The number of progeny emergence was increased as the increase of  superparasitism rate. The number of progeny emergence from single oviposition host was 15, while from host exposed on female parasitoid for 3, 5, 7, and 9 times were 12, 5, 2 and 0, respectively. The developmental time of immature progeny was lengthened as the increase of superparasitism rate. Sex ratio of progeny was biased to female progeny as the increase of rate of superparasitism. The result of this research indicated that superparasitism gave negative effect on development of T. brontispae progeny