Judul: Use of border crops and Coccinellid predators to control the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), a vector of Begomovirus on chillipepper (Capsicum annuum L.)
Abstrak: Whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) is an important pest on chillipepper due to its role as a vector of Begomovirus, the causal agent of yellow leaf curl disease. Many efforts has been undergone to suppress disease incidence, such as through controlling insect vector, B. tabaci. The objective of the research were to study the effect of border crops in chillipepper plantation on population of B. tabaci and incidence of yellow leaf curl disease as well as abundance and effectiveness of predator species. Field experiment was conducted using randomized completed design. Two seedling treatments (with and without cover), were combined with 4 border treatments i.e. maize, crotalaria (Fabaceae), chiffon fabric and non border. The potency of predator species was evaluated by conducting 3 consequtive assays, i.e. predation, prey preference and functional response assay. The results showed that the use of covered seedling was able to protect the seedling from B. tabaci and delay virus infection for 2 weeks. Population of B. tabaci was significantly lower in plot with combination of border crops and covered seedling. Correlation between population of B. tabaci and disease incidence was positif (r = 0.925), where as correlation between disease incidence and yield crop was negative (r = - 0.8886). Border crops especially maize could enhance the abundance of predator species with the most predators commonly found species were Menochilus sexmaculatus, Coccinella transversalis and Verania lineata. The predator species which have highest potency as natural enemy to control B. tabaci are V. lineata (Coleoptera: Coccinellidae)
Keyword: 

Judul: Genetik ketahanan cabai terhadap begomovirus penyebab penyakit daun keriting kuning dan arah pemuliaannya, Genetics of resistance on chili pepper to yellow leaf curl begomovirus and strategy breeding
Abstrak: Begomovirus has been reported as the major pathogen for various important crops, including chilli pepper. Disease severity and yield loss caused by Begomovirus infection are affected by several factors, among others are plant varieties, viral strains and time of infection. The use of resistance varieties is considered as the most effective way to control the disease. Research activities were conducted to study the genetics of resistance of chilli pepper varieties to Pepper yellow leaf curl Begomovirus, in order to develop resistance chilli pepper varieties. Preliminary experiment was conducted to determine the transmission method using insect vector, Bemisia tabaci followed by determination of plant stage for inoculation of Begomovirus. Individual inoculation using 10 insects per plant with 24 h acquisition period and 48 h inoculation period on cotyledon stage was considered as the most effective and efficient way for Begomovirus transmission. Type of symptoms develop from Begomovirus infection can be differentiated into 5 groups, i.e (1) yellowing (2) yellowing and leaf curling (3) yellowing, leaf cupping with leaf curling, upward or downward, (4) yellowing, leaf cupping with leaf curling, upward and downward (5) yellowing, leaf curling, stunting. Twenty seven genotypes of chilli pepper were evaluated for their resistance based on score/type at symptoms and disease intensity. Disease intensity was ranged from 2.40% to 100% and they were group grouped into resistance (1 genotipe), moderate resistance (4 genotipes), moderate susceptible (4 genotipes), susceptible (8 genotipes) and highly susceptible (10 genotipes). Further analysis showed that resistance genotype (IPBC12) has more trichome than susceptible genotype (35C2) does salicylic acid contain was not significantly different between two genotypes, although Begomovirus infection could increase salicylic acid contain in resistance genotype. Genetic studies for resistance of chilli pepper to Yellow leaf curl Begomovirus was conducted using two methods, i.e. (1) analysis ofbasic population using six-population analysis and (2) analysis of random mating using diallel analysis. The result indicated that pepper resistance to Begomovirus was controlled by polygenes and there was extrachromosomal effect. The degree of dominance were over dominant. Gene action for resistance were additive, dominant and additive x additive interaction. However one population (IPBClO x IPBC14) showed additive gene action, dominant, additive x additive and dominant x dominant interaction. Estimation of broad-sense heritability were high but narrow-sense heritability were low to high. IPBC12 dan IPBC10 have the best combining ability for resistance to Begomovirus whereas IPBC14 have the highest yield. There are four crossing, i.e. IPBC10xIPBC12, IPBC12xIPBC14, IPBC14xIPBC18, dan IPBC18xIPBC26, that good combining ability and heterosis for resistance to Begomovirus and yield. Resistance verieties to Begomovirus could be established through hybrid cultivars to benefit the effect of dominance gene action. However, it could also be developed through open pollination using bulk or pedigree method.
Keyword: resistance, susceptible, combining ability, chilli pepper, Begomovirus

Judul: Kekuatan Tiga Tipe Sambungan Kayu Merbau pada Lunas Luar Kapal Ikan
Abstrak: Kapal kayu terdiri dari bagian-bagian yang merupakan satu kesatuan utuh. Bagian-bagian tersebut tidak dapat dipisahkan karena antara satu bagian dengan bagian yang lainnya saling menunjang. Diantara bagian-bagian tersebut, terdapat safu bagian yang merupakan dasar penunjang dari bagian-bagian yang lain pada kapal~ yaitu lunas. Lunas merupakan bagian dilsar pada kap~ awal dari pembangunan sebuah kapal yang juga berperan sebagai tulang punggung kapal. Lunas merupakan tempat menempelnya kerangka lambung atau gading-gading. Lunas juga berfungsi sebagai penyangga badan kapal dan mnatan yang berada di dalam kapal~ Beban yang disangga oleh lunas tergantung dilri besar kapal dan berat muatan yang dibawa oleli kapaL OIeh karena itu, material lunas harus terbnat dari kayu yang kuat, agar pada saat muatan kapal penuh, lUnas mampu menyangga beban dan kapaI tidak mengalami kerusakan. Menurut BKI (1989) kayu material lunas harus termasuk dalam kelompok kayu kelas kuat satu atan di.Ja. Lunas dipasang secara horizontaI searah panjang kap~ oleh karena itu, seIain kuat, lunas juga hams terbuat dari kayu yang panjang. Saat ini terdapat kesulitan untuk mencari kayu yang panjang karena semakin berkurangnya pohon-pohon tinggi di liutan. Siilitnya mencari kayu yang panjang menyebabkan funas kapal tidak seIalu terdiri dari satu batang kayu utuli yang panjang, tetapi juga terdiri diIri dua batang kayu sejenis yang disambung dengan sambungan. Sambungan yang digunakan pada lUnas kapaI harusIah sambungan yang kuat, agar lunas tetap mampu menyangga beban kapal dan muatan kapal.
Keyword: