Abstract. Sopialena, Rosfiansyah, Sila S. 2017. The benefit of top soil and fertilizer mixture to improve the ex-coal mining land. Nusantara Bioscience 9: 36-43. The mining activities have led severe impacts on some environmental issues including a decrease in soil fertility, which affects the ability of soil to supply soil nutrients to growing plants, a destruction in soil structure, and the loss of microorganisms, which are important for reforming process to treat organic materials. In this regards, reclamation of mined degraded land has been continually used to improve soil structure and its microorganisms. In practice, for large scale reclamation, fertilizer use can primarily enhance soil qualities in improving plant's growth and yield. It is suggested that healthy soil should contain millions of microorganisms at the aggregation which leads to the improvement of soil nutrients and its structure, as the medium for plant growth. For this purpose, therefore, this study aimed to determine the impact of organic fertilizer (Ostindo) and top soil mixture on microbial diversity, soil fertility and the growth of sengon (Paraserianthes falcataria L. Nielsen). This study made use of a randomized block design, using four treatments and five replications including P0: without top soil and fertilizer, P1: with top soil but without fertilizer, P2: without top soil but with fertilizer, P3: mixture of top soil and fertilizer. The results showed that a mixture of top soil and fertilizer has successfully increased in the number of fungal genus, starting from two genus (Phytium and Penicillium) turning into five genus (Phytium, Fusarium, Penicillium, Aspergillus, and Rhizoctonia), as well as in the number of nematode genus, from two (Dorylaimus and Rhabditis) turning into five genus (Dorylaimus, Steinernema, Dorylaimus, Hoplolaimus, and Mononchus). This study indicated that the mixture has significantly improved soil health in ex-coal mining land, which was viable through the pH level (almost neutral), the significant increase of C, N and P 2 O 5 , and also the growth of Sengon. In conclusion, this study succeeds in demonstrating that the mixture of top soil and fertilizer has enhanced the microbial diversity, soil fertility, and sengon growth.

Sopialena, Sila S, Rosfiansyah, Nurdiana J. 2018. The role of neem leaves as organic pesticides in chili pepper (Capsicum frutescens). Nusantara Bioscience 10: 246-250. The agricultural crops and horticultural plants are always under constant assault caused by diseases, insect pests, viruses, and other pathogens which may substantially reduce yield. Chili Pepper (Capsicum annum L.) is a popular horticultural plant of the Solanaceae family in Indonesia. Some serious diseases widely found in chili peppers, are anthracnose (Colletotrichum capsici), leaf spot (Cercospora capsici) and fruit rot (Phytophthora capsici). To manage the potential problems, this study is aimed to provide an explanatory knowledge of the use of plant-based pesticide to control the diseases in chili peppers. The information is meant to fill the knowledge gaps in the use of plant-based pesticide to control the chili diseases. The use of nonchemical pesticide benefits not only the environment but also as an organic strategy for disease management. This research used a randomized complete block design (RCBD) categorized into four groups and six different treatments. The organic pesticides were prepared from the extract of neem leaves, soursop leaves, lemongrass extract, tuba root extract, and kenikir/Cosmos caudatus extract). The result indicates that neem leaves are the most effective organic pesticides to control the chili pepper disease in Indonesia.

Suyadi, Rosfiansyah. 2017. The role of plant parasitic nematodes on productivity reduction of banana and tomato in East Kalimantan, Indonesia. Asian J Agric 1: xxxx. Plant parasitic nematode is one of the most limiting factor of agricultural ecosystem productivity in East Kalimantan, but their occurrence in agricultural field as a crop’s pest generally undistinguished, due to their microscopic size and their existence wrapped in the roots or soil particles. However, plant parasitic nematodes might cause yield loss up to 75%, without showed any disease symptom on crop morphologically. Perennial crop and annual crop under intensive cultivation usually experience high yield loss due to plant parasitic nematodes, if crop protection management was not implemented properly. This research aimed to determine the role of plant parasitic nematodes in reducing crop’s productivity in East Kalimantan, in relation to agricultural practices implemented by farmers. A descriptive research and comparative analyses were implemented to determine the role of plant parasitic nematode on yield reduction of banana and tomato as the indicator of productivity. Based on the field observation related to pest management in East Kalimantan, it was determined that plant parasitic nematode existence was neglected by farmers and no significant effort was implemented to control plant parasitic nematodes population. Therefore, low productivity of agricultural ecosystem in East Kalimantan was reported by Statistical Office, and it was not only caused by soil fertility problems, in some crops it was also the impact of population outbreak of plant parasitic nematodes. The first ranking three genera of plant parasite nematodes observed in East Kalimantan were Meloidogyne, Radhopholus, and Rotylenchulus, respectively. Meloidogyne and Rotylenchulus were major pest on vegetables, and caused yield loss >50% on tomato. While, genus of Radhopholus was the major pest on banana, and caused yield loss >75% on banana.