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One method of controlling disease that is environmentally friendly is the use of plant-based pesticides also known as botanical pesticides. The use of botanical pesticides has proven to be effective in controlling several species of pests and plant diseases, because they contains active secondary metabolite compounds. These compounds affect pathogenic microorganisms, so it is feared will also affect antagonistic microorganisms. This research will find out the impact of the application of several botanical pesticides on shallots to microbial biodiversity. The study was conducted in Peat-lands, at South Kalimantan. Microbial identification was carried out at the Phytopathology Laboratory and the Laboratory of Biological Control of the Department of Pests and Plant Diseases, Lambung Mangkurat University, Banjarbaru. The results showed that the application of plant-based pesticides from Kepayang fruit extract and Galam leaf extract had an influence in decreasing the population of microorganisms, respectively by 80.44% and 75.26%. Chirinyuh were increased the population by 36.60%, as well as the control treatment, the population of microorganisms increased by 17.77%. Meanwhile the application of synthetic pesticide Dhitane M-45 reduced the population of microorganisms by 95.73%. Types of microbes found in the soil and onion rhizosphere are Pseudomonas flourescens, Bacillus sp., Fusarium sp., Aspergillus sp., Curvularia sp., Scopulariopsis sp., Stachybotrys bisbyi, and Penicillium sp.

Peatlands with very high C contents are generally considered a source of greenhouse gas (GHG) emissions. This research aimed to quantify the changes in peatland characteristics and GHG emission from the conversion of peatlands to agricultural areas. Height of water table, pH, electrical conductivity (EC), redox potential (Eh), organic carbon (OC), hot water-soluble C, total-N, the concentrations of NH4 +, and NO3 −, soluble-Al, soluble- Fe, and the emission of CH4, CO2 and N2O were quantified before and after land clearing of peats for agriculture. Results of study showed that pH, EC, OC contents, hot water-soluble-C, and total-N did not change after peatland clearing for agriculture. On the other hand, the concentrations of NH4 +, NO3 −, soluble-Al, soluble-Fe, redox potential and height of water table increased significantly after the peatland land clearing. Methane emissions from peatlands before peatland clearing were in the range of 0.13-0.22 mg C m−2 h−1 increased significantly to 0.14-0.31 mg C m−2 h−1 after the peatland clearing. The land clearing of peatlands for agricultural practices also caused increases in CO2 and NOx emissions by 85% and 76%, respectively. Changes in GGH emissions were not related to the changes in substrates quality of peats (OC contents, total-N and hot water- soluble-C). Results of the study indicate that increases in the GHG emission following the use of peatlands for agricultural areas are attributed to the changes in the peat characteristics.

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The utilization of peatlands may decline the ecological functions of peatlands as carbon sink, water storage and biodiversity source. Therefore, different scientific approaches are required to increase peat productivity and inhibit decline in the ecological functions of peatlands. This article is aimed to provide information on researches that have been carried out in tropical peats in the South Kalimantan Province. The exploration and the potential utilization of microbes was reviewed from several studies conducted in the Desa Landasan Ulin Utara (LaURa), Kota Banjarbaru, South Kalimantan Province. Peat research carried out in the Desa LaURa during the dry season after peat fires in 2015 showed that microbial SRBM (mixture of N fixing, solubilizing P and cellulolytic microorganisms) from the modified recharge bio-pore system was able to improve the growth of roots, stems, and leaves, nutrient uptake, and increase production and biomass of soybean. In another research in 2018, the use of commercial biofertilizers containing Azotobacter sp and Lactobacillus sp applied to the LaURa peats significantly increased the total N and pH of peats but did not accelerate the decomposition of peat materials. In subsequent study on the exploration of nitrogen fixing microorganisms from the LaURa peats (sapric peats) which amounted to 10375-10500 cells g−1, the total N-fixing microbial population was correlated positively to the pH and EC of peats, and correlated negatively to the contents of peat organic C. Combining the results, the total N2 fixing microbial (NFM) population was significantly affected by organic C and peat EC (total NFM population = -154.052 + 33.126 pH + 607.117 EC, R2 = 51.63%). Results obtained from these studies demonstrated that the functional microbes of peatlands are able to maintain ecological functions of the peats.

Penyakit moler pada tanaman bawang merah yang disebabkan oleh Fusarium oxysporum f.sp cepae termasuk penyakit yang sangat berbahaya karena serangannya yang cepat, menyebabkan tanaman mati dan berakibat gagal panen. Pengendalian penyakit sendiri memiliki berbagai macam cara yaitu menggunakan pestisida nabati, agen hayati, maupun kimia. Cara alternatif dalam pengendalian penyakit moler  yaitu menggunakan agen hayati Trichoderma sp agar mengurangi resiko dari penggunaan bahan kimia. Tujuan dilakukannya penelitian ini adalah untuk mengetahui kemampuan tiga isolat Trichoderma sp. asal lahan rawa pasang surut dalam mengendalikan penyakit moler pada bawang merah. Penelitian menggunakan Rancangan Acak Lengkap yang terdiri dari 6 perlakuan dan 4 ulangan, sehingga terbentuk 24 satuan percobaan. Perlakuan terdiri dari T0 Tanpa pemberian Trichoderma  dan tanpa inokulasi Fusarium, T1 Tanpa pemberian Trichoderma dan inokulasi Fusarium, T2a Kontrol dengan menggunakan fungisida Benlate dan Fusarium, T3 Trichoderma asal isolat Kaladan, Kab. Tapin dan Fusarium, T4 Trichoderma asal isolat Landasan Ulin dan Fusarium,  T5 Trichoderma asal isolat Barambai Kab. Barito Kuala dan Fusarium. Hasil penelitian menunjukkan bahwa Trichoderma sp. mampu menekan serangan penyakit layu Fusarium pada tanaman bawang merah Intensitas serangan tertinggi ditemukan pada perlakuan kontrol yaitu tanaman yang diinokulasi Fusarium oxysporum dengan nilai sebesar 100%, sedangkan tanaman bawang merah yang diberi perlakuan Trichoderma sp. mampu menahan serangan F. oxysporum dengan intensitas serangan sebesar 0. Tiga isolat Trichoderma sp. yakni asal Kaladan, Landasan Ulin dan Barambai, efektif mengendalikan penyakit moler bawang merah yang disebabkan oleh Fusarium oxysporum f.sp

Indicator Plant and PCR-RAPD for Biotype Determination of Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae).B. tabaci has been known world wide as a major pest and virus vector of horticulture. In Indonesia the presence of B.tabaci was reported since 1980 and its role as virus vector in tomato and chilli pepper has becoming more importantrecently. Genetic diversity of B. tabaci has been well recognized, but very little information available for diversity of B.tabaci in Indonesia. This research was conducted in Bogor, West Java from May 2004 to June 2005. The aim of thisresearch was to initiate basic information regarding genetic diversity of B. tabaci in Indonesia, particularly in Java Island.Whiteflies population collected from different crops, i.e. tomato, broccoli, chill pepper, eggplant, cucumber, soybean, andedamame, was evaluated using silverleaf-induction test, and RAPD-PCR. It was evidenced that only B. tabaci populationfrom broccoli was able to induce silverleaf. Two genetic types of B. tabaci, i.e. biotype B and non B, were identified basedon polymorphism character of DNA. Population from broccoli was belong to biotype B, whereas other populations fromtomato, chill pepper, eggplant, cucumber, soybean, and edamame were belong to biotype non B.

Chili is an important commodity for most people, because of its function in terms of improving taste and appetite. Chili was seriously developed with the support of government funds for chili farmers. The development of chili plants, has enough obstacles, especially wich caused by plant disturbing organisms whether it is pests or diseases. The important organism that disturbs chili is wilting caused by Ralstonia solanacearum. In South Kalimantan, this disease reportedly attacked chilies spread in the districts of Banjar, Banjarbaru, Barito Kuala, Tapin, Hulu Sungai Tengah and Balangan with a cumulative attack area of 15,7 ha on 2017 (South Kalimantan BPTPH Database). This disease is important because of the nature of the attack which can cause the plants to wilt suddenly all part of the plant. Plants wich attacked by bacterial wilt cannot be cured. The effort that can be done in prevention before pathogens infect the plants (Sastra, 2004). One way to overcome this problem is biological control using biological agents from the type of antagonistic bacteria Bacillus spp, Pseudomonas fluorescens, and type of antagonistic fungus Trichoderma spp. From three biological agents proven able to inhibit the development of R. solanacearum in vitro which produces a zone of inhibition as wide as 13,5 mm for Bacillus spp, 22,25 mm for Pseudomonas fluorescens and 8,42 mm for Trichoderma spp. and can increase plant height growth, chili weight, root weight, wet weight, and dry weight plants. Trichoderma spp as the best biological agents for increasing chili growth and yield.