Judul: Preferences of Ants on Pineapple Plantations on Various Bait Formulation
Abstrak: Budidaya nanas di Indonesia masih memiliki hambatan salah satunya yaitu serangan virus Pineapple mealybug wilt-associated virus (PMWaV) yang menyebabkan penyakit layu mealybug (PLM). Penyakit ini ditularkan oleh serangga vektor kutu putih yang dibantu oleh semut. Pentingnya peranan semut terhadap populasi kutu putih mengakibatkan pengendalian hama kutu putih difokuskan pada pengelolaan semut yang bersimbiosis mutualisme dengan kutu putih dengan berbagai formulasi umpan. Tujuan penelitian untuk mengetahui semut yang berasosiasi dengan kutu putih dan mengetahui umpan formulasi yang paling diminati oleh semut. Penelitian dilaksanakan dalam tujuh tahap, yaitu penentuan lokasi pengamatan, pengambilan sampel semut, koleksi dan identifikasi, pembuatan formulasi umpan, preferensi makan semut terhadap umpan di sarang, preferensi makan semut terhadap umpan di laboratorium, serta analisis data. Penentuan semut untuk pengujian berdasarkan sampel semut yang ditemukan berasosiasi dengan kutu putih. Uji preferensi di laboratorium dengan metode choice dan no-choice. Hasil penelitian menunjukkan bahwa semut yang ditemukan berasosiasi dengan kutu putih adalah Pheidole dan Tapinoma melanocephalum. Uji preferensi semut Pheidole menunjukkan formulasi paling diminati yaitu Formulasi 6 (protein tinggi), sedangkan umpan yang paling diminati Tapinoma melanocephalum adalah Formulasi 5 (tinggi gula [glukosa dan sukrosa]). Implikasi dari penelitian ini adalah diketahuinya formulasi yang paling disukai oleh semut, sehingga formulasi tersebut dapat digunakan untuk pengendalian semut di lapangan., Pineapple cultivation in Indonesia still has obstacles, namely attacks by the Pineapple mealybug wilt-associated virus (PMWaV) which causes mealybug wilt disease. This disease is transmitted by the mealybug as vector were. The spread of mealybugs from one plant to another is assisted by ants The important role of ants in mealybug populations has resulted in control of mealybug pests being focused on managing using various bait formulations. The aim of the research was to find out which ants are associated with mealybugs and find out which bait formulations are most popular with ants. The research was carried out in seven stages, namely determining the observation location, taking ant samples, collection and identification, making bait formulations, preferences of ants towards bait in the nest and laboratory, and data analysis. The determination of ants for testing was based on samples of ants found associated with mealybugs. Test preferences in the laboratory using the choice and no-choice method. The ants found associated with mealybugs were Pheidole sp. and Tapinoma melanocephalum. The Pheidole preference test showed that the most preferred formulation was Formulation 6 (high protein), whereas Tapinoma melanocephalum ant preference test showed that the most popular bait was Formulation 5 (high sugar [glucose and sucrose]). The implications of this study were most preferred formulation can be used for ant control in the field.
Keyword: ant, bait formulation, preference, semut, umpan formulasi, preferensi

Judul: Test of the Effectiveness of Thermal Hydrolysis of  Pineapple (Ananas comosus L. Merr.) Waste for Insecticide Substitution in  Controlling Mealybugs (Dysmicoccus brevipes).
Abstrak: M.AZIZ IZZATULLAH. Uji Efektivitas Hidrolisis Termal Limbah Nanas (Ananas comosus L. Merr.) untuk Subtitusi Insektisida dalam Pengendalian Kutu Putih (Dysmicoccus brevipes). Dibimbing oleh HERDHATA AGUSTA dan DHIKA PRITA HAPSARI. Produksi nanas yang tinggi selain menghasilkan keuntungan yang besar namun juga menghasilkan limbah yang tinggi, limbah tersebut dapat memberi efek negatif terhadap lingkungan kita. Peningkatan produksi nanas dapat dipicu dengan pemeliharaan yang baik mulai dari pengairan, pemberian fungisida, herbisida dan insektisida. insektisida biasa digunakan untuk menangani hama yang menurunkan produktivitas panen. Penelitian ini bertujuan untuk menganalisis efektivitas insektisida dari ekstrak limbah nanas terhadap hama kutu putih. Percobaan dilaksanakan di PT Great Giant Pineapple (GGP). Kecamatan Terbanggi Besar, Kabupaten Lampung Tengah, Lampung, Indonesia. Penelitian disusun dengan menggunakan Rancangan Kelompok Lengkap Teracak (RKLT) Tersarang satu faktor. Perlakuan dibagi menjadi 8 kombinasi perlakuan konsentrasi limbah nanas atau hidrolisat (H), asap cair (A), dan Standar (S). Yaitu 0% (kontrol), standar, 80%S+20%H, 60%S + 40%H, 80%S +2 0%A, 60%S + 40%A, 80%S + 10%H + 10%A, 60%S + 200%H + 20%A. Setiap perlakuan diulang sebanyak 20 kali sehingga terdapat 140 satuan unit percobaan pada uji insektisida nabati. Pengaplikasian insektisida nabati berbahan baku limbah bromelain nanas, berpengaruh nyata pada tinggi tanaman, lebar daun, dan kematian kutu putih dan tidak berpengaruh nyata terhadap panjang daun. Larutan kombinasi insektisida nabati menyebabkan kematian hama kutu putih (mealybug) sebesar 100% setelah hari ke-3 dan hari ke 6, baik pada substitusi aplikasi pestisida sintetik sebesar 20% maupun 40%. Hidrolisat tersebut mampu menggantikan kebutuhan sintetik standar hingga 20% bahkan 40% untuk pengendalian kutu putih nanas pada crown nanas Kata kunci: asap cair, crown, kematian, M. AZIZ IZZATULLAH. Test of the Effectiveness of Thermal Hydrolysis of Pineapple (Ananas comosus L. Merr.) Waste for Insecticide Substitution in Controlling Mealybugs (Dysmicoccus brevipes). Supervised by HERDHATA AGUSTA and DHIKA PRITA HAPSARI. High pineapple production not only produces large profits but also produces high levels of waste, this waste can have a negative effect on our environment. Increasing pineapple production can be triggered by good maintenance starting from irrigation, applying fungicides, herbicides and insecticides. Insecticides are commonly used to treat pests that reduce crop productivity. This research aims to analyze the effectiveness of insecticides from pineapple waste extract against mealybug pests. The experiment will be carried out at PT Great Giant Pineapple (GGP). Terbanggi Besar District, Central Lampung Regency, Lampung, Indonesia. The research was structured using a Randomized Complete Group Design (RKLT) nested on one factor. The treatments were divided into 8 treatment combinations of pineapple waste concentration or hydrolyzate (H), liquid smoke (A), and Standard (S). Namely 0% (control), standard, 80%S+20%H, 60%S + 40%H, 80%S +2 0%A, 60%S + 40%A, 80%S + 10%H + 10%A, 60%S + 200%H + 20%A. Each treatment was repeated 20 times so that there were 140 experimental units in the vegetable insecticide test. The application of a botanical insecticide made from pineapple bromelain waste had a significant effect on plant height, leaf width and mealybug death and had no significant effect on leaf length. The combination solution of vegetable insecticides caused 100% death of mealybugs after day 3 and day 6, both at 20%
Keyword: asap cair, crown, kematian

Judul: Bifurkasi Hopf pada Model Siklus Bisnis Kaldor Kalecki tanpa dan dengan Waktu Tunda
Abstrak: Business cycle model is one of dynamical system models in economic. One of the business cycles model is Kaldor-Kalecki model. Kaldor-Kalecki business cycle model that is written in delayed defferential equations, is a business cycle model that involves gross product and capital stock of a company. In this paper Kaldor-Kalecki business cycle model is analyzed using both nondelay and delay in time of capital stock. By Taylor expansion for the time delayed model, an analysis of stability around the fixed points has been done. Furthermore, by using Hopf bifurcation theorem, it can be shown that there exists periodic orbits and limit cycle. In the nondelayed model, changing the parameter of goods market could lead to the occurrence of Hopf bifurcation and the existence of limit cycle. Similarly, for the delayed model, it has been shown that changing the time delay parameter may result in the occurrence of Hopf bifurcation and limit cycle.
Keyword: