A total of 70 bacteria were isolated from the rhizosphere of potato cv. Hartapel that grew at an altitude of 700 m above sea level on the island of Buru-Maluku. Of these isolates, 36 isolates were capable of producing IAA, GA, Siderophore and phosphate solubilization. Among the selective isolates, isolate HB8 produced the highest amount of IAA (5.816 mg l -1 ), while isolate HB32 produced the highest amount of GA (6.879 mg l -1 ). Isolate HB18 had the best ability in producing salicylate type siderophore (4.214 mg l -1 ) and isolate HB3 showed the highest phosphate solubilization (14.237 mg l -1 ). There were three isolates (HB3, HB8 and HB31) positively produced HCN. All 36 isolate showed physiological characters which revealed the potential use for biostimulant, biofertilizer and bioprotectant against soil borne pathogens.

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An appropriate in vitro propagation medium is necessary to improve the shoot multiplication ability and seed quality in micro propagation. In the Murashige Shoog in vitro culture medium, plant growth regulator can be added as growth promoter. This study aimed to determine the best IAA concentration for in vitro culture growth of Japanese taro (satoimo). The treatment consisted of 4 IAA concentrations, i.e. I0 (0 mg / l), I1 (0.5 mg/L), I2 (1 mg/L), I3 (1.5 mg/L) in randomized block design, with 5 replicates. The results of this study showed that IAA treatment gave an effect on the time of shoot emergence, shoot number, leaf number and root number of satoimo plantlet. IAA concentration of 0.5 mg/L was the best for satoimo shoot number, whereas 1 mg/L IAA was the best concentration for shoot number, shoot height and leaf number in micropropagation of satoimo. Keywords: IAA, in vitro culture, Japanese taro, micro propagation   ABSTRAK Media perbanyakan in vitrosangat diperlukan untuk meningkatkan kemampuan multipikasi tunas maupun kualitas bibit. Media Murashige Shoog (MS)dapatditambahkanzat pengatur tumbuh sebagai pemacu pertumbuhan dalam kultur in vitro.Penelitian ini bertujuan untuk mendapatkan konsentrasi IAA terbaik bagi pertumbuhan talas jepang dalam kulturin vitro. Perlakuan terdiri dari 4 taraf konsentrasi IAA yaitu I0 (0 mg/L), I1 (0,5 mg/L), I2 (1 mg/L), I3 (1,5 mg/L) yang diulang sebanyak 5 kali dalam rancangan acak kelompok. Hasil penelitian ini menunjukan bahwa pemberian IAA berpengaruh nyata terhadap saat muncul tunas, jumlah tunas, tinggi tunas, jumlah daun dan jumlah akar satoimo. Konsentrasi IAA 0,5 mg/L merupakan konsentrasi terbaik untuk pertumbuhan akar dan saat muncul tunas talas satoimo, sedangkan konsentrasi IAA 1 mg/L merupakan konsentrasi terbaik untuk jumlah tunas, tinggi tunas dan jumlah daun satoimo. Kata kunci: kultur in vitro, talas jepang, IAA, perbanyakan

Abstract. Syamsia S, Idhan A, Firmansyah AP, Noerfitryani N, Rahim I, Kesaulya H, Armus R. 2021. Combination on endophytic fungal as the Plant Growth-Promoting Fungi (PGPF) on Cucumber (Cucumis sativus). Biodiversitas 22: 1194-1202. Endophytic fungi are known to stimulate plant growth by producing secondary metabolites, including phytohormones (IAA and Gibberellins), siderophore, phosphate-solubilizing metabolites. In this study, a total of six endophytic fungi were successfully isolated from local rice plants and showed different abilities in producing secondary metabolites, during single isolates testing. These six isolates were then combined to obtain 15 combinations for analysis, to determine the best combination for application as a plant growth promoter. Subsequently, each combination was tested for phytohormones (IAA, gibberellins) and siderophore (quantitatively)-producing activity, phosphate-solubilizing ability, and the effect on cucumber (Cucumis sativus L) plant growth. F13 showed activity in producing IAA and produced the highest gibberellin levels, while F1 exhibited the highest phosphate-solubilizing activity. In addition, F11 (Na-salicylate) and F1 (catechol) showed the highest siderophore activity, while a combination of F6, F8, F9, and F12 successfully increased plant height growth. Also, F4 increased the root growth, while the fresh weight of cucumber was increased by F8 treatment, under controlled conditions. Molecular analysis showed the tested isolates have close similarity to Daldinia eschscholtzii, Sarocladium oryzae, Rhizoctonia oryzae, Penicillium allahabadense, and Aspergillus foetidus. The combination of endophyte fungal isolates showed potential as plant growth promoters, however, further testing on several plant types is required before the combination is to be widely applied.

This study aimed to determine the effect of different biostimulant applications (solid and liquid) on the growth and yield of mustard plants. This study used a single factor Randomized Block Design (RBD), consisting of solid or liquid biostimulant treatment, each has twelve levels, i.e. K0 = without biostimulant, K1 = NPK 1 g per plant, solid and liquid biostimulant each consisting of 10 treatments = B1, B2, B3, B4, B5, B6, B7, B8, B9, B10. Solid biostimulant was given at 2.5 g per plant and liquid biostimulant at 10 ml per plant. The results showed that liquid biostimulant gave a significant effect on plant height, crop fresh weight, and crop dry weight; whereas solid biostimulant gave a very significant effect on entire weight, i.e. fresh weight of mustard plant, fresh root weight, and crop dry weight. The best treatment for liquid biostimulant was B1 treatment; whereas for the solid biostimulant was B7 treatment. Keywords: biostimulant, mustard, growth, yield   ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh aplikasi biostimulan yang berbeda (biostimulan padat dan cair) terhadap pertumbuhan dan produksi tanaman sawi. Penelitian ini menggunakan rancangan acak kelompok faktor tunggal yang terdiri dari perlakuan Biostimulan (padat dan cair) yang masing-masing perlakuan terdapat dua belas taraf (P): K0 = tanpa biostimulan, K1 = NPK 1 g/tan, Biostimulan padat dan cair masing-masing terdiri dari 10 perlakuan = B1, B2, B3, B4, B5, B6, B7, B8, B9, B10. Biostimulan padat 2.5 g/tan dan biostimulan cair 10 ml/tan. Hasil penelitian menunjukkan bahwa biostimulan cair memberikan pengaruh yang nyata terhadap tinggi tanaman sawi, berat segar tanaman, dan berat kering tanaman, sedangkan biostimulan padat memberikan pengaruh yang sangat nyata terhadap semua bobot berat tanaman sawi yaitu berat segar tanaman, berat segar akar, dan berat kering tanaman. Perlakuan terbaik untuk biostimulan cair adalah perlakuan B1, sedangkan untuk biostimulan padat perlakuan yang terbaik adalah perlakuan B7. Kata kunci: biostimulan, sawi, pertumbuhan, produksi