Abstract:Despite the recent interest in biochar and digestate as soil amendments for improving soil quality and increasing crop production, there is inadequate knowledge of the effect of the combination of biochar and digestate, particularly under saline irrigation conditions. A pot experiment with Chinese melon was conducted in a greenhouse, biochar (5%) and digestate (500 mL/pot) were used with and without the recommended mineral NPK (Nitrogen, Phosphorus and Potassium) fertilizer dose (120-150-150 Kg ha −1 ). The plants were irrigated with tap water (SL0) and 2 dS/m (SL1) NaCl solution. The growth, photosynthesis rate, water use efficiency (WUE) and yield of Chinese melon were affected positively when biochar was combined with digestate amendment, particularly under saline irrigation water with and without mineral NPK fertilizer. The maximum yield under normal water was obtained by digestate (SL0: 218.87 t ha −1 ) and biochar amendment combined with digestate (SL1: 118.8 t ha −1 ) under saline water. The maximum WUE values were noticed with the biochar and digestate combination under all water treatments (SL0: 32.2 t ha −1 mm −1 and SL1: 19.6 t ha −1 mm −1 ). It was concluded that digestate alone was more effective than the use of biochar, particularly with normal water. The combination of biochar with digestate had a significant effect on the Chinese melon growth, photosynthesis rate, water use efficiency and yield under saline irrigation, and it can be used as an alternative fertilizer for mineral NPK fertilizer.

Various indexes should be considered when developing a suitable irrigation and drainage scheme for crops. Our study chosen tomato as plant material and conducted a field experiment under saline soils. Nine treatments distinguished by different irrigation quotas and different drain ditch depths were used for the optimization of irrigation-drainage scheme. A flooding irrigation treatment with no surface drainage was adopted as control. The system of evaluation indexes was established in comprehensive consideration of the electrical conductivity and nutrient of soil, and the water use efficiency, nitrogen use efficiency, quality and marketable yield of tomato. Moreover, the multi-index analysis and projection pursuit (PP) model were used to evaluate the irrigation-drainage schemes according to the observed values of these six evaluation indexes. Results showed that different irrigationdrainage treatments decreased the electrical conductivity in plough layer by 24.6-51.3%, and increased the tomato water use efficiency and nitrogen use efficiency by 0.3-24.2% and 20.3-96.0%, respectively. The tomato marketable yield was increased by 14.4-31.3% with the irrigation-drainage treatments when compared to the control. As analyzed by the PP model, I3D1 (300 m 3 hm -2 of irrigation quota combined with 10 cm of ditch depth) was the treatment that possessed best comprehensive benefits due to the highest projection value of 1.6724 thus was recommended by this study as the optimal irrigation-drainage scheme.

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She (2015) Development and evaluation of Trichoderma asperellum preparation for control of sheath blight of rice (Oryza sativa L.), Biocontrol Science and Technology, 25:3, 316-328, Sheath blight, which is caused by Rhizoctonia solani, is a disease that majorly impacts rice production. A biocontrol agent used for control rice sheath blight must be sprayed on the stem at specific times during rice growth, a process that is labourintensive and renders the antagonist vulnerable to environmental factors. In this study, Trichoderma asperellum T12 was used to produce preparation by solid-state fermentation using a surface-response method. Rice hull was selected as a carrier based on its ability to sustain the T12 floating in the water and protect T12 from ultraviolet irradiation. The production of a T12-based preparation required 32% wheat bran, 7% inoculum, 2.3 g kg −1 (NH 4 ) 2 SO 4 and 65% water content, with fermentation at 27.5°C for 30 days and agitation every six days. The preparation demonstrated 90% biocontrol efficacy and significantly (P > 0.05) increased the seed-set rate and 1000-grain weight as compared with the pathogen treatment. The population of Trichoderma on the surface of rice leaf sheath in the treatment applied with T12 preparation increased from 232 cfu (colony forming units) g −1 fw (fresh weight) to 436 cfu g −1 fw during rice growth stage, which was significantly (P > 0.05) higher than pathogen treatment. The population of R. solani on the leaf sheath increased from 41 cfu g −1 fw to 271 cfu g −1 fw in the pathogen treatment, while remained stable (P > 0.05) at level of 10-23 cfu g −1 fw in T12 preparation applied treatment. Biocontrol of sheath blight by the addition of the preparation to the soil is effective and decreases the costs of agro-industrial waste disposal.