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The study aimed to obtain the type of mulch and the doses of liquid organic fertilizer proper waste coconut husks in modifying microclimate around crops to obtain the maximum yield of shallot in the dryland. The research was used a factorial randomized complete block design consisting of two factors. The first factor consisting mulches, M1 = silver-black plastic mulch and M2 = straw mulch. The dose of liquid organic fertilizer from coconut husks was the second factor. It is consisting of S0 = without fertilizer, S1 = 500 L ha-1, S2 = 750 L ha-1 and S3 = 1000 L ha-1. The results showed that the application of a combination of mulch and liquid organic fertilizer coconut husk waste significantly affected plant height, number of leaves per plant, number of tillers, and the bulb yield. Straw mulch with coconut husks waste dose of 1000 L ha-1 resulted in plant height, number of leaves per plant, number of tillers and highest bulb yield compared with other treatments. The highest bulb yield was obtained with 9.63 t ha-1.

<p><strong>Background</strong>. Shallot plant is an important commodity in Central Sulawesi because it functions as a raw material in the fried onion home-industry. <strong>Objective.</strong> The aim of this study was to evaluate the effect of mulch and organic fertilizers on the agronomic performance of the “Lembah Palu” variety of shallot (<em>Allium cepa </em>L. var. <em>Aggregatum</em>) on dryland. <strong>Methodology.</strong> The experiment consisted of three types of mulch (no mulching, rice straw, and <em>Gliricidia sepium</em> leaf) and four types of organic fertilizers (no fertilizer, bioculture, biourin and cattle manure compost). The experiment was laid out as a randomized complete block design in a factorial arrangement with three replications. A total of 36 plots were used for the experiment. The agronomic performance measured were: plant height, number of leaves per plant, number of tillers, fresh weight, dry weight, bulb diameter and bulb yield of shallot. Environmental parameters include temperature and humidity. <strong>Result.</strong> Results showed that the application of rice straw mulch plus bioculture organic fertilizer had positive  significant effect (<em>P≤ 0.05</em>, respectively) on next agronomic parameters: plant height, number of leaves per plant, number of tillers, fresh weight, dry weight, bulb diameter and yield bulb of shallot. <strong>Implications. </strong>Significantly positive results on the agronomic parameters of shallots indicate that the application of mulch and bioculture organic fertilizers can be used on other crops to increasing the efficiency of dryland.<strong> </strong><strong>Conclusion.</strong> The highest production of shallots was 9.46 t^.ha^-1. Thus, it can be recommended that straw mulch at a dose of 5 t^.ha^-1 and bioculture at a dose of 750 L^.ha^-1 is better for the growth and yield of shallot in dryland. The use of rice straw mulch and bioculture as organic liquid fertilizer provides benefits to increase productivity, add value to the crop and livestock waste, reduce environmental pollution, and application to plants will produce healthy products.</p><strong></strong>

Vascular streak dieback<em> (VSD) caused by </em>Ceratobasidium theobromae<em> is a major disease in cacao which results in</em><em> yield losses up to 45%. Controlling VSD using secondary metabolites and botanical fungicide is expected to reduce disease attacks because secondary metabolites contain antibiotics, enzymes, and toxins that can control the disease and botanical fungicide that are antifungal. The research aimed to determine the effect of </em>Trichoderma <em>spp. secondary metabolites and botanical fungicide to control VSD in cacao. The research was conducted in the Integrated Laboratory, IIBCRI, Sukabumi, Biotechnology Laboratory, BPPT, Serpong and farmer gardens in Rahmat Village, Palolo District, Sigi Regency, Central Sulawesi, from March to December 2017. The research used a randomized block design of 7 treatments with 3 replications; each replication consists of 10 plants. The treatments were: (1) </em>Trichoderma virens<em> LP1, (2) </em>T. amazonicum<em> LP3, (3) botanical fungicide, (4) </em>T. virens<em> LP1 + botanical fungicide, (5) </em>T. amazonicum<em> LP3 + botanical fungicide, (6) chemical fungicide (for comparison), (7) control (without application).</em><em> Variables observed were the symptoms of the attack, severity and disease progression, and production. The results showed that </em>Trichoderma <em>spp. secondary metabolite</em><em>s suppress VSD disease severity and increase cacao production up to 33.97%–61.34%, either in a single form or in combination with botanical fungicide. </em>T. virens<em> LP1 secondary metabolite </em><em>showed the highest suppression of VSD disease (54.18%), followed by the combination of T. virens LP1 + botanical fungicide (47.64%), better than chemical fungicide (30.89%). Thus, </em>Trichoderma <em>spp. secondary metabolites can be used as a VSD control technology.</em>

Arbuscular mycorrhizal fungi (AMF), a plant root-fungus association, has been studied widely across different ecosystems. However, little information provided in tropical land use systems. Here, we studied the diversity of AMF in the forest, cacao agroforestry, and cacao plantation. A preliminary survey was done to estimate the AMF richness and diversity. This study reveals an interesting fundamental finding where AMF richness and diversity were significantly higher in the plantation compared to the natural ecosystem. AMF communities were significantly affected mixed vegetation in the forest and became a generalist in an agroecosystem of the cocoa plantation. Presented results indicate that AMF diversity and community structure are influenced by vegetation and ecological conditions.