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Chili production in Indonesia is fluctuating due to the complex of pests and diseases including Thrips, mites, yellow leaf curl virus, and Fusarium wilt. Farmers mainly rely on pesticides in solving the problem, which leads to becoming the source of new problems. Numerous efforts have been made to find alternative methods to control those unwanted organisms, including crop immunization using particular crops. The study aimed to determine the effectiveness of leaf extract of pagoda flowers and spiny amaranth to induce chili resistance against unwanted organisms and suppress pests' development. The research, arranged in Randomized Block Design with 5 treatments and five replicates, was conducted in Bocek village, Karangploso sub-district, Malang Regency, East Java Province, Indonesia from April to August 2019. The treatments were: P1 ('Proliga'+Pagoda flower leaf extract), P1 ('Proliga'+spiny amaranth leaf extract), P2 (farmer technological package Malang Regency), P3 (farmer technological package from Blitar Regency), and P4 (check plot of no control measure application). The leaf extracts were sprayed on the chili seedling in the nursery. The highest pest control efficacy was recorded on the application of spiny amaranth leaf extract in controlling mites (P. latus), Thrips sp., viruses, and Fusarium wilt attacks that reached up to 86.15%, 85.17%, 89.09%, and 89.05% respectively compared to check plot. While the lowest efficacy was recorded on the use of Pagoda flower leaf extract. [ABSTRACT FROM AUTHOR]

The recently observed honey bee colony losses have already raised concerns about the future of the managed honey bees and the bees in general. One of the most powerful approach to simulate and predict the dynamics of a complex system, which a honey bee colony undoubtedly is, is the mathematical modelling. We have adopted a compartment model to study the behaviour in a honey bee colony. A system of three ordinary differential equations with a control on the mites was introduced to model the populations of the hive bees, forager bees and mites. We solve a parameter identification inverse problem to reconstruct the values, which are directly unobservable but vital in honeybee management. We apply an adjoint equation optimization approach to solve the inverse problem. Numerical test examples are discussed and the paper is concluded with important implications about the honey bee management. [ABSTRACT FROM AUTHOR]