Ginger is an economically important commodity of Indonesia. A diamond shape leaf spot disease has been reported in ginger cultivation areas. The aim of this study was to determine the causal agent of the disease. Two isolates were obtained by a single conidia isolation method on Pyricularia typical conidia, followed by propagation on a PDA medium. The conidial suspensions were sprayed onto leaf of white and red ginger types for pathogenicity test. The inoculated plants were placed at room temperature with 80%-90% air humidity for 48 hr, then put back in the green house. The fungal identity was determined based on its morphological characteristic and confirmed by molecular characterization through DNA extraction and amplification using ITS5 and ITS4 primers. The optimal growth temperature of the fungus was assayed by planting each isolate onto PDA medium, then incubated at 4 level temperatures. The same temperature levels was also tested on conidial germination, on WA medium. The artificial inoculation showed both isolates infected all types of ginger, but red ginger showed lower in disease severity. Morphologically, both isolates are corresponding to Pyricularia zingiberi. The fungus grows optimally between 25 °C and 31 °C. PCR analysis supported the morphological observation results.

Diamond shape leaf spot disease caused by Pyricularia zingiberi is an essential disease in red ginger. This current research aims to identify the potency of essential oil formula and silica fertilizer against the diamond shape leaf spot disease. Efficacy of clove oil, lemongrass oil, and mancozeb as a control against the colony growth was tested by inoculating the fungus on PDA medium amended with 50, 100, 150, 200, 250, and 300 ppm of the tested fungicides. Compared to lemongrass oil, clove oil (LC50: 70,79 ppm) is more effective in suppressing the growth of P. zingiberi. In a greenhouse, the leaves of five months old red ginger plants were inoculated by spraying 105 conidia mL−1 suspensions of P. zingiberi. Foliar application of clove oil base pesticide and silica was carried out a month before pathogen inoculation, arranged in the factorial randomized complete design. The disease severity was measured monthly, and the data were analyzed using ANOVA. Disease severity on the plant treated by either clove oil base pesticide or silica was 9,08% and 8,71% lower than control (20,21%). Further research is still needed. Treatment with clove oil base pesticide or silica shows potency in reducing the disease severity.

In order to get the healthy black pepper plant, the presence of various types of pest organisms should be controlled below the economic threshold. One of the efforts to obtain an environmentally friendly control strategy is by using natural pesticides i.e.entomophatogenic fungi, Beauveria bassiana and clove oil-based botanical pesticides. The insects tested in this study were pepper stem borer, Lophobaris piperis, and pepper fruit sucker, Dasynus piperis. The results of the laboratory bioassays showed that 20 gr / l of B. bassiana could kill some of the tested insects, but its toxicity in the field tended to be low. Mortality of L. piperis and D. piperis at the end of laboratory assay was 20% and 33.3%, respectively. Therefore, to get maximum impacts, field application must be repeated several times at intervals of 1 to 2 months. The botanical pesticide formula at the highest concentration (20 cc/l) was able to kill 43.3% of L. piperis. Meanwhile, it was very effective against D. piperis at a concentration of 2.5 cc/l, which was able to kill all the tested insects. The botanical pesticides and B bassiana have potential to control D piperis and L piperis..

Nowadays, there are many foods that contain harmful substances in the community. Among them are fried foods that contain plastic. Similar cases were also found in the campus area in city of Padang. Based on preliminary observations it was found that some fried foods sold in one campus area in the city of Padang were indicated to contain plastic. This study therefore aims to determine whether fried foods sold in the city of Padang contained plastic, what the physical characteristics of fried foods that contain plastic were, and what plastic content contained in the cooking oil. This type of research was descriptive qualitative. Sampling in this study was conducted by purposive sampling in 16 locations around the campus area in the city of Padang. The data of the research data were obtained from physical and chemical sample identifications. Physical identification included data on shape, color, fragility, and fuel test. Physically indicated samples containing plastic then analyzed chemically with GC-MS. The results of the study showed that the physical characteristics of fried foods that contain plastic were black clots when observed with a microscope, there are white patches on the surface of the fried, brittle for hours, and if it was burned, it burnt and produced melt. The results of the chemical analysis showed that from 16 sampling points 11 samples (68.75%) positive contained plastic. The type of plastic compound found was from PVC (Polyvinyl chloride).