اثر مصرف مقادیر نیتروژن همراه با بیوچار و نانوذرات روی بر خصوصیات کمی و کیفی برنج (Oryza Sativa L.)

به‌منظور بررسی اثرات مصرف مقادیر مختلف نیتروژن همراه با کاربرد بیوچار پوسته برنج و نانوذرات روی بر خصوصیات کمی و کیفی برنج رقم طارم هاشمی، آزمایشی به‌صورت کرت‌های خرد شده در قالب طرح بلوک‌های کامل تصادفی با سه تکرار در مزرعه شخصی واقع در شهرستان آمل در سال زراعی 99-1398 اجرا شد. مصرف مقادیر نیتروژن در چهار سطح (صفر، 25، 50 و 75 کیلوگرم در هکتار) از منبع کود اوره به‌عنوان عامل اصلی و کاربرد کودهای بیوچار (40 تن در هکتار) و نانوذرات روی (50 میلی‌گرم بر لیتر) در چهار سطح شامل: 1 شاهد (عدم مصرف بیوچار و نانواکسید روی)، 2 کاربرد بیوچار، 3 کاربرد نانواکسید روی و 4 کاربرد ترکیبی بیوچار و نانواکسید روی به‌عنوان عامل فرعی در نظر گرفته شدند. نتایج نشان داد که کاربرد کود نیتروژن در مقادیر 50 و 75 کیلوگرم در هکتار به‌ترتیب موجب حصول حداکثر عملکرد دانه (4340 کیلوگرم در هکتار) و تولید بالاترین غلظت نیتروژن دانه (1.30 درصد) گردید. کاربرد ترکیبی بیوچار و نانوذرات روی سبب افزایش معنی‌دار خصوصیات کمی و کیفی برنج گردید، به گونه‌ای که بیشترین عملکرد دانه تولیدی (4062 کیلوگرم در هکتار) و حداکثر غلظت روی در دانه (28.5 میلی‌گرم بر کیلوگرم) در شرایط کاربرد همزمان بیوچار + نانوذرات مشاهده شد. با توجه به نتایج مطالعه حاضر، مصرف نیتروژن به میزان 50 کیلوگرم در هکتار و کاربرد همزمان بیوچار پوسته برنج + نانوذرات روی به‌عنوان مقدار بهینه نیتروژن و گزینه مطلوب کودی جهت افزایش عملکرد محصول و غنی‌سازی دانه برنج شناخته شدند.

Effect of Application of Nitrogen Doses Along with Biochar and Zinc Nanoparticles on Quantitative and Qualitative Characteristics of Rice (Oryza sativa L.)

IntroductionAmong the various nutrients, nitrogen (N) is the limiting element for crop yield, which application of the optimum doses of this fertilizer in addition to increasing the yield components and grain yield in paddy fields, enhances the profits of rice cultivation in the region. One of the sustainable soil management techniques in paddy fields is the application of rice husk biochar. Biochar improves rice yield by improving soil chemical properties, increasing nutrient storage capacity, and also reducing soil acidity. Zinc deficiency can be the most important limiting factor of rice yield after N, P, and K. Therefore, the application of zinc fertilizer in the form of nanoparticles can be an effective technique to increase the quantitative and qualitative characteristics of rice. Therefore, the present study was conducted to investigate the effects of nitrogen doses along with the application of biochar and also zinc fertilizer in the form of nanoparticles on the quantitative and qualitative characteristics of rice.Materials and MethodsThe field experiment was carried out as a splitplot based on a randomized complete block design with three replications at the farmer’s field located in Amol (North of Iran) in cropping season of 20192020. In this study, the doses of nitrogen applied at four levels of 0, 25, 50, and 75 kg.ha1 as the main factor and application of fertilizers at four levels of control or no application of biochar and zinc nanoparticles, application of biochar, foliar application of zinc nanoparticles and combined application of biochar and zinc nanoparticles as the subfactor were considered. The fertilizers of biochar and zinc nanoparticles at 40 ton.ha1 and 50 mg.l1 were used in this experiment, respectively. At harvest time, the yield components, yield, and N and Zn concentrations in grain were measured. Analysis of variance was performed using SAS software (ver. 9.2) and mean comparisons based on the least significant difference (LSD) test at the level of 5% probability.Results and DiscussionThe results showed that the simple effects of experimental treatments were significant on all morphological traits, yield components, and grain yield except the number of filled grains per panicle. The grain N concentration was not affected by biochar and zinc, while grain Zn concentration was significant under this treatment. Also, the impact of N application was significant on N and Zn concentrations in grain. The interaction between experimental treatments was not significant on the studied traits except for the number of fertile tillers per hill. The maximum fertile tillers number per hill (17.66 tillers) was obtained by using a combination of biochar + zinc nanoparticles + 50 kg N ha1, which indicates the positive impacts of simultaneous application of these fertilizers. The application of N fertilizer at the amounts of 50 and 75 kg.ha1, respectively, resulted in maximum grain yield (4340 kg.ha1) and production of the highest grain N concentration (1.30%). Although the use of each of the biochar and zinc oxide nanoparticles improved the yield components, yield, and nutrient concentrations in rice grain, the combined application of biochar and zinc nanoparticles significantly increased the quantitative and qualitative characteristics of rice, so that the highest grain yield (4062 kg.ha1) and greatest Zn concentration in grain (28.5 mg.kg1) was observed under the simultaneous application of biochar + nanoparticles.ConclusionAccording to the results of the present study, N application at the rate of 50 kg.ha1 and simultaneous application of rice husk biochar + zinc nanoparticles are introduced as the optimal dose of N and the ideal fertilizer option to increase crop yield and enrich rice grains.