FULL-LENGTH RESEARCH ARTICLE Effect of Bioslurry on the Yield of Wheat and Rice in the Wheat– Rice Cropping System M. A. Haque 1 • M. Jahiruddin 2 • M. S. Islam 1 • M. M. Rahman 2 • M. A. Saleque 3 Received: 18 December 2017 / Accepted: 14 June 2018 Ó NAAS (National Academy of Agricultural Sciences) 2018 Abstract The study was conducted to assess the integrated use of chemical fertilizers with organic manure in the wheat– rice cropping systems in Bangladesh. The experiment involved a sole chemical fertilizer treatment, four treatments based on the integrated plant nutrition system (IPNS) with 5 t ha -1 cowdung (CD) and cowdung bioslurry, 3 t ha -1 poultry manure (PM) and poultry manure bioslurry and a control. The wheat crop received manures and/or bioslurries, and its residual effect was evaluated for succeeding T. Aman crop. Poultry manure bioslurry, poultry manure, cowdung bioslurry, and cowdung gave 11.7, 8.9, 5.4, and 3.1% respective increase in total system productivity over sole chemical fertilizer (46% N, as urea, 20% P as triple superphosphate, 50% K as muriate of potash and 18% S as gypsum). Bioslurries supplied greater amount of nutrients compared to their respective original state of soil which influenced nutrient uptake of the test crop. Cowdung bioslurry is recommended as a substitute of 24–32% N, 52–91% P, 18–24% K and 50–73% S and that for poultry manure bioslurry of 19–21% N, 87–94% P, 12–14% K and 49–61% S of the recommended nutrient rate. The plant analysis showed that total N, P, K, and S contents improved significantly by integrated use of CD and PM bioslurry with IPNS based chemical fertilizers. Total system productivity (TSP) was significantly influenced by different treatments which ranged from 3.43 to 7.88 t ha -1 in 2011 and 3.66 to 7.82 t ha -1 in 2012. Keywords Bioslurry Á Wheat–rice system Á Yield Á Integrated plant nutrition system Á Cowdung Á Poultry manure Á Total system productivity Á Bangladesh Introduction The increasing population and limited land force our farmers to maximize crop yields per unit area through intensive cultivation. Organic manure plays a vital role in retaining soil fertility and crop production in a sustainable way. The application of organic sources alone to fulfill the plant nutrient requirements is facing problems due to its low nutrient contents and high dosage of application [18, 19]. Consequently, application of organic manures can be helpful in obtaining the sustainability of crop production [31]. Bioslurry is one of the organic sources which have been obtained as by-product of fermented biogas generated through the anaerobic decomposition of various organic materials that can be used for crop production [1, 18, 30, 43]. After extraction of biogas (50–70% CH 4 , 30–40% CO 2 ), residual bioslurry is drained out from the digester which is rich in macronutrients (N, K, P and S) and micronutrients (B, Zn and Cu) [26, 37]. The application of bioslurry as manure can reduce the loss of nitrogen due to the anaerobic conditions in the digester [12]. Bioslurry technology is becoming popular in the rural areas of Bangladesh in view of escalating cost of fuels as & M. A. Haque masadulh@yahoo.com & M. S. Islam islam-md.saiful-nj@ynu.jp 1 Department of Soil Science, Patuakhali Science and Technology University, Patuakhali 8602, Bangladesh 2 Department of Soil Science, Bangladesh Agricultural University, Mymensingh, Bangladesh 3 Bangladesh Rice Research Institute, Gazipur, Bangladesh 123 Agric Res https://doi.org/10.1007/s40003-018-0333-7