Submit Manuscript | http://medcraveonline.com Introduction Excessive inorganic fertilizers and plant protection chemicals usages in crop production induce risks of both human health and environment. Besides, generally 50% of N and 90% of P from applied inorganic fertilizers are fxed up in soils and run off, and ultimately it releases into atmosphere and water sources, which contribute for greenhouse gas generation, eutrophication and soil salinization. 1,2 Application of excessive P induce cadmium in soil that come to food chains. 3 Moreover nitrogen application increase nitrates in ground water which are fnally responsible for N-nitroso compounds and ultimately often linked with fatal methemoglobinemia. 4 To minimize these problems the relevant researchers have been trying to develop sustainable safe and environmental friendly technologies that will help to minimize usages of chemical fertilizers for crop production. Accordingly Trichoderma spp. enriched bio-organic fertilizers; pellets and suspension are being evaluated to monitor its performance in different crop production. 5‒7 In recent years it has achieved recognition as plant growth promoter, enhanced antioxidant compounds, 7,8 increased yield of several crops in feld condition. 6,10‒12 Besides, some Trichoderma rhizosphere-competent strains have been shown to have direct effects on plants, increasing their growth potential and nutrient uptake, fertilizer usage effciency, percentage and rate of seed germination, and stimulation of plant defense against biotic and abiotic damages. 13,14 Trichoderma metabolites and roots colonization by Trichoderma change the proteome and transcriptome of plants, 15,16 which enhance plant growth and development but these mechanisms of Trichoderma plant interaction are not quite easy. Application of Trichoderma fungi ensures the favorable environment for growing and proliferation of abundant healthy roots and simultaneously plant derived sucrose which is an important resource provided by the Trichoderma spp. Cells. 17 Thus plants become benefted from this relationship through increased root and shoot growth and increased macro- and micronutrient uptake. Therefore, Trichoderma spp. are being treated as growth promoting (bio- organic fertilizer) as well as pathogen control agent (mycofungicide) and their application may lower the production cost of crops along with conserving congenial environment. Vegetable cultivation is one of the most important and dynamic wing of agriculture in Bangladesh. Among the cultivated vegetables in Bangladesh, bottle gourd (Lagenaria spp.) a cucurbit is a popular crop has now drawing attention to greater extent. Bottle gourd (Lagenaria spp.) is a common and delicious winter vegetable in Bangladesh. Generally bottle gourd fruits are used as fruit vegetable, but its leaves tender stem are used as delicious and nutritious leafy vegetable. 18 It is reported as an easily digestible vegetable which keeps the body cool and prevents constipation. Its cultivation and usages are wide in winter but now a day it is cultivating during summer and rainy season also. Bottle gourd is vine crop grow rapidly and their stem become 10-12 meter long which generally need support to climb by the pole along the stem. It prefers well-drained, moist, rich soil and proper fertilizer management practices for successful crop growth and yield. 19 At this situation, slow release nutrient rich fertilizers/compost/bio-organic fertilizer might contribute signifcant roles for bottle gourd cultivation. Bio-organic fertilizer is defned as the fertilizer contained living cells or latent cells of effcient strains of microorganisms with decompose Horticult Int J. 2018;2(3):106‒114. 106 © 2018 Barua et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Performance of Trichoderma-enriched bio-organic fertilizer in N supplementation and bottle gourd production in feld condition Volume 2 Issue 3 - 2018 Sujan Barua, 1 Abul Hossain Molla, 1 Md. Manjurul Haque, 1 M Saiful Alam 2 1 Department of Environmental Science, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Bangladesh 2 Department of Soil Science, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Bangladesh Correspondence: Abul Hossain Molla, Department of Environmental Science, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur -1706, Bangladesh, Email ahmolla60@gmail.com Received: May 28, 2018 | Published: June 07, 2018 Abstract Bio-organic fertilizer plays a signifcant role to conserve suitable soil environment for plant growth and development. Trichoderma-enriched bio-organic fertilizer (BOF) was evaluated for bottle gourd cultivation to assess suitable dose and mode of application at feld condition. The experiment was conducted in two successive years (2014/15 and 2015/16) with three replications and eight treatments of standard dose (SD) of NPK fertilizer and different doses of BOF in two modes of application. Application of BOF with 25% N of standard nitrogen dose played superior roles in present study. The highest dose (3kg/pit with 25%N+100%PK) of BOF offered the highest yield which was statistically similar to SD of NPK in both the years. But sole application (SA) of the highest dose at planting time provided 10.25% higher yield of bottle gourd compared to SD of NPK application. Conversely, 13.95 and 7.69% lower yield was monitored in frst and second year, respectively by the split (double) application of the same amount of BOF compared to SD of NPK application. Trichoderma- enriched bio-organic fertilizer could save at least 75%N fertilizer usages and ensured earlier fruit setting in bottle gourd production. In the present study the highest dose (i. e. 3kg/pit of BOF & 25%N with 100%PK as of standard dose of NPK) and sole application of BOF presented superior performance to split application. Trichoderma enriched bio-organic fertilizer could serve prospective and potential roles in promotion of crop cultivation with reducing usages of N-fertilizer in future. Keywords: bottle gourd, male and female fower, fruit diameter, fruit length, yield, sole, split application Horticulture International Journal Research Article Open Access