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Aims: The objective of this work is to evaluate the effect of (aqueous (EAq) and methanolic (ME)) extracts of Thevetia peruviana on the in vitro development of Rigidoporus lignosus. Study Design: A synthetic fungicide (Onazol 100), two extracts at differents concentrations: C1 = 3.5 mg / ml; C2 = 7 mg / ml; C3 = 15 mg / ml; C4 = 30 mg / ml; C5 = 50 mg / ml and C6 = 100 mg / ml for EAq; C1 = 3.5 ml/ml; C2 = 7 ml/ml; C3 = 15 ml/ml; C4 = 30 ml/ml; C5 = 50 ml/ml for ME and a negative control (T = 0 mg / ml) were used. Place and Duration of Study: The study was conducted in pathology laboratory at University of Yaounde I and IRAD of Nkolbisson in 2018. Methodology: Daily measurements of the pathogen's development was used to evaluate the average growth (D) of the mycelium. The inhibition percentages of the different doses of EAq, ME and ONAZOL 100 were calculated after 4 to 5 days of growth of the fungus. Results: The major result obtained compared to the rate of rot showed that the treatments EAq, ME (C6) and ONAZOL 100 were closed. The disease rates at different concentrations of C1 to C6 were 13.91 to 100% for ME, 9.34 to 100% for EAq, and 100% for ONAZOL 100. Conclusion: The two extracts are promising, and on small and medium scale, could be an effective and cheap formulation for the control of Rigidoporus lignosus.

One of the main obstacles in rubber cultivation is the white root fungus (JAP) attack which caused by Rigidophorus ligonosus. This pathogen infects rubber plants from the nursery until the mature plants. Efforts to control the disease have been carried out by chemical, technical culture and use of biological agencies. This research was conducted at the STIP-AP Medan in January 2017 to June 2017, this study used a non-factorial Randomized Block Design (RBD) with four replications and four treatments. Using Trichoderma koningii with somes doses were 20 grams, 30 grams, and 40 grams/seedling. The results of this study indicate that the biofungicide application of Trichoderma koningii 30 g/seedling produces the greatest inhibition of the rubber plants seedling nursery against the growth of pathogens Rigidoporus lignosus.

Cultivation of nutmeg (Myristica fragrans) is running into several problems, one of these is caused by white root fungus (Rigidoporus lignosus) which causes losses to nutmeg farmers. This fungus is known to be controlled by biological control using microorganisms such as Penicillium sp. This research was conducted to determine the efficacy of application time of Penicillium sp. crude extract against white root fungus (Rigidoporus lignosus) in nutmeg plants. The design used in this study was a non-factorial completely randomized design with the main factor being the application time of Penicilllium sp. crude extract with 4 treatments. Each treatment on 7 replicates. Control without suspension application Penicillium sp. (PK0), Application of Penicillium sp. 7 days before inoculation of Rigidoporus lignosus (PK1), Application of suspension of Penicillium sp. concurrently with Rigidoporus lignosus (PK2) inoculation, Application of suspension of Penicillium sp. 7 days after Rigidoporus lignosus (PK3) inoculation. Total are 28 experimental units. In this case, the test plants used are 11 months old nutmeg. The research parameters consisted of the incubation period, disease incidence and attack intensity. The results showed that the treatment at one-time application of the suspension of Penicillium sp. Significantly affect the intensity of attacks and the incidence of infectious disease pathogens Rigidoporus lignosus. Application time for Penicillium sp. 7 days before the suspension of Rigidoporus lignosus is the best offer in the attack of Rigidoporus lignosus disease.

White root disease caused byRigidoporus lignosusis one of most serious disease in rubber plantation. Until now, research about white root disease relates to electrical properties is still less. Hence, this research investigated the differences in electrical properties of healthy and white root disease through dielectric constant value. Seventy six samples of healthy and white root disease respectively were collected from rubber estate located in Kota Tinggi, Johor. Measurement of dielectric constant value for both conditions of latex has been done using Electrochemical Impedance Spectroscopy (EIS) in the range of frequency between 50 Hz up to 10 kHz. The result obtained from this measurement was proceeding with the statistical analysis to analyze the differences of healthy and white root disease. It was found that at frequency 150 Hz, the dielectric constant of healthy and white root disease have show significant differences.

The study was conducted to evaluate in vitro and in vivo control of fungal antagonists on Rigidoporus lignosus (klotzsch) Imaz in Hevea brasiliensis (Willd. ex A. Juss.) Muell. Arg. in the rain forest zone of Nigeria. In vitro assessments of biological agents were carried out in dixenic cultures in Petri plates. In vivo tests were carried out in the nursery using Hypocrea virens and Hypocrea jecorina. Significant differences were observed with the dual inoculations of fungal antagonists and R. lignosus inoculated the same day, and the antagonists inoculated 24 h before inoculation of R. lignosus. Hypocrea jecorina was most effective in the control of R. lignosus with percentage inhibition of 86.83 %. Hypocrea virens, H. jecorina, Trichoderma spirale, Trichoderma sp., Trichoderma sp. Pers, and Hypocrea lixii were effective on R. lignosus. Fungal antagonists inoculated 24 h before inoculation of R. lignosus exhibited higher inhibitory efficacies than antagonists and R. lignosus inoculated the same day. In the in vivo evaluation of fungi antagonists on R. lignosus, seedlings in H. jecorina treatment at 60 d and H. virens treatment at 150 d after inoculations respectively had the highest plant heaths (highest length of stem and length of tap rot, lowest plant death, and least foliar symptom) compared to the control. Mortality rate was higher at 60 d after inoculation and decline from the third months onward. Significant differences were observed between the control and R. lignosus treatment in all the parameters evaluated.

White Root Fungus Disease (JAP) is the biggest threat in rubber. The attack can result in a significant reduction in number, especially in plants lasting 0-3 years. The pathogen that causes white fungus is Rigidoporus lignosus. In JAP endemic areas, decreased tree density 40-50%. In rubber seedlings, symptoms of JAP attack with yellowing color leaves, then dry and fall. This study was conducted at STIP-AP Medan from January 2017 to June 2017. The aim of the study was to determine the effectiveness of several doses of hexaconazole. This study uses a non-factorial Randomized Block Design (RBD) with four replications. Hexaconazole fungicides are active with treatment of A0, A1, A2, A3 and A4 (0, 5, 10, 15 and 20 ml / l air). The results of this study indicate that A2 application of hexaconazole-active fungicides (10 ml / l air) has been effective in controlling JAP disease in rubber seedlings.

Monitoring of phenolic compounds in the food industry and for environmental and medical applications has become more relevant in recent years. Conventional methods for detection and quantification of these compounds, such as spectrophotometry and chromatography, are time consuming and expensive. However, laccase biosensors represent a fast method for on-line and in situ monitoring of these compounds. We discuss the main transduction principles. We divide the electrochemical principle into amperometric, voltammetric, potentiometric and conductometric sensors. We divide optical transducers into fluorescence and absorption. The amperometric transducer method is the most widely studied and used for laccase biosensors. Optical biosensors present higher sensitivity than the other biosensors. Laccase production is dominated by a few fungus genera: Trametes, Aspergillus, and Ganoderma. We present an overview of laccase biosensors used for the determination of phenolic compounds in industrial applications. © 2015 The Authors.