نوع مقاله : کاربردی

نویسندگان

• علیرضا جعفرنژادی ¹
• فرهاد مشیری ²
• فاطمه مسکینی ویشکایی ³

¹ دانشیار بخش تحقیقات خاک و آب، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی خوزستان، سازمان تحقیقات، آموزش و ترویج کشاورزی(AREEO)، اهواز، ایران

² دانشیار بخش تحقیقات تغذیه گیاه و حاصلخیزی خاک، موسسه تحقیقات خاک و آب، سازمان تحقیقات، آموزش و ترویج کشاورزی(AREEO)، کرج، ایران

³ استادیار بخش تحقیقات خاک و آب، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان خوزستان، سازمان تحقیقات، آموزش و ترویج کشاورزی، اهواز، ایران

چکیده

امروزه استفاده تلفیقی از کودهای آلی و شیمیایی برای تولید پایدار و حفظ منابع خاک اجتناب‌ناپذیر می‌باشد. به منظور مطالعه تأثیر طولانی‌مدت کاربرد توام کودهای شیمیایی و آلی بر برخی ویژگی‌های خاک و محتوای عناصر غذایی خاک و دانه گندم در کرت‌های ثابت، پژوهشی در شش تیمار مدیریت مصرف کودهای آلی و شیمیایی در سه تکرار و در قالب طرح بلوک‌های کامل تصادفی به مدت 4 سال در استان خوزستان اجرا شد. تیمارهای آزمایشی شامل شاهد بدون کاربرد کود شیمیایی (T1)، کاربرد کودهای شیمیایی NPK بر اساس آزمون خاک (T2)، کاربرد کود گاوی هر دو سال یکبار+ 75 درصد نیتروژن توصیه شده + 50 درصد فسفر و پتاسیم توصیه شده (T3)، کاربرد کمپوست باگاس نیشکر هر دو سال یکبار + 75 درصد نیتروژن توصیه شده + 50 درصد فسفر و پتاسیم توصیه شده (T4)، کاربرد سالانه کود گاوی + 75 درصد نیتروژن توصیه شده (T5)، کاربرد سالانه کمپوست باگاس نیشکر + 75 درصد نیتروژن توصیه شده (T6) بودند. کاربرد تیمارهای کودی (به-جز تیمار T2 کاربرد انحصاری کود شیمیایی) تأثیر معنی‌داری بر شوری خاک نداشتند. بیشترین افزایش معنی‌دار کربن آلی خاک (حدود 13/0 درصد) در تیمارهای کاربرد تلفیقی کود گاوی و کودهای شیمیایی (T3 و T5) مشاهده شد. بیشترین مقدار فسفر و پتاسیم قابل دسترس خاک به‌ترتیب برابر با 8/19 و 3/253 میلی‌گرم در کیلوگرم در تیمار T3 به دست آمد. نتایج نشان داد که تیمارهای کودی تأثیر معنی‌داری بر محتوای فسفر و پتاسیم دانه گندم نداشتند. اما، بیشترین مقدار نیتروژن دانه گندم (06/2 میلی‌گرم در کیلوگرم) نیز در تیمار T3 مشاهده شد (38 درصد افزایش نسبت به تیمار شاهد). نتایج مؤید تأثیر بیشتر کود دامی نسبت به باگاس نیشکر بر بهبود محتوای عناصر غذایی خاک و گیاه بود. بنابراین، کاربرد 20 تن کود گاوی هر دو سال یکبار+ 75 درصد نیتروژن توصیه شده + 50 درصد فسفر و پتاسیم توصیه شده در مزارع گندم استان خوزستان توصیه می‌شود.

کلیدواژه‌ها

• خاک شور- آهکی
• کشاورزی پایدار
• کمپوست باگاس نیشکر
• کود گاوی

موضوعات

• تغذیه گیاه، حاصلخیزی خاک و کودها

عنوان مقاله [English]

Evaluation of the nutrient content of soil and wheat grain due to the integrated application of chemical and organic fertilizers

نویسندگان [English]

• Ali Reza Jafarnejadi ¹
• Farhad Moshiri ²
• Fatemeh Meskini-Vishkaee ³

¹ Associate Professor, Soil and Water Research Department, Khuzestan Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Ahvaz, Iran

² Associate Professor, Soil fertility and Plant nutrition, soil and water research institute, , Education and Extension Organization(AREEO), Karaj. Iran

³ Assistant Professor, Soil and Water Research Department, Khuzestan Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education and Extension Organization (AREEO), Ahvaz, Iran.

چکیده [English]

Introduction Arid and semi-arid areas such as Khuzestan province has highly fragile ecosystems that are characterized by low soil fertility, and high organic matter decomposition rates. Moreover, according to the FAO, around 12% of world soils and 65% of Iran's soils are calcareous and more than 20 % of the irrigated farms in the world is affected by salinity. Since soil carbon saturation is low in saline-calcareous soils, the use of organic manure can be effective in increasing soil organic carbon and supplying essential nutrients in crop production. Applying organic manure in agriculture has been considered during the last two decades due to its high-quality products, high price, and low market availability of synthetic fertilizers, chiefly in developing countries. The manure application, both alone or in combination with inorganic fertilizers, is effective in increasing soil organic carbon (SOC) content and improve in soil fertility, microbial activity, and soil water retention capacity. Now the integrated application of organic and chemical fertilizers is inevitable for sustainable production and soil conservation. Hence, comprehension of the response of the soil and crop to applying organic and inorganic fertilizer may help to determine proper manure management strategies to enhance SOC and improve soil health and its ecosystem services. Thus, the aim of the study was to investigate the effects of different fertilizer managements on nutrient content of soil and wheat in saline-calcareous soils of Khuzestan province.

Materials and Methods To evaluate the effect of the integrated and long-term application of chemical and organic fertilizers on the nutrient content of soil and wheat grain in fixed plots, this research was carried out in Khuzestan province (Ahvaz city) in a calcareous- saline soil with silty clay texture under wheat cultivation (Barat cultivar) as a randomized complete block design in six treatments with three replications for four years (2017-2021). The treatments included T1: unfertilized control, T2: application of nitrogenous, phosphorus and potassium chemical fertilizers based on soil test, T3: application of 20 tons of cattle manure every two years + 75% of recommended nitrogen + 50% of the recommended phosphorus and potassium, T4: application 20 tons of bagasse every two years + 75% of the recommended nitrogen + 50% of the recommended phosphorus and potassium, T5: annual application of 20 tons of cattle manure + 75% of the recommended nitrogen, T6: annual application of 20 tons of bagasse + 75% of the recommended nitrogen. In treatment T2 recommended dose of P2O5, K2O, and 30 % of recommended N were applied at the time of second irrigation; the remaining N dose was applied in two splits at tillering (40 % of recommended N) and booting stages (30 % of recommended N). The organic manures were incorporated in the soil (depth 0-15 cm) a week before sowing. At the end of the growing season, wheat yield components were measured. At the end of the growth season, some soil properties involved pH, salinity and SOC, and the concentration of nitrogen, phosphorous and potassium in soil and grain wheat were determined. SAS v.9.1 statistical software and LSD test were used to compare the means of the studied treatments.

Results and Discussion The mean values of SOC varied in range of 0.60 to 0.73 %. As a result of applying treatment T2 (inorganic fertilizers application as alone), no significant difference was observed in SOC compared to the control treatment (p< 0.05). Compared to unfertilized control treatment, the SOC content were increased significantly by the use of cattle manure at T3 treatment (0.13 %), which could be attributed to the larger proportion of tenacious organic compounds in organic fertilizers than in chemical fertilizer. The highest concentration of soil available phosphorus (19.8 mg kg-1) was obtained in the integrated application of chemical fertilizer and cattle manure (T3), which is 60 and 169 % higher than those in the exclusive chemical fertilizer application (12.35 mg kg-1) and control (7.35 mg kg-1) treatments, respectively. The highest average soil available potassium concentration (253.3 mg kg-1) was also observed in T3. The results showed that the application of different fertilizer treatments was significant only on the nitrogen concentration of wheat grain (p< 0.01). The increase in wheat grain nitrogen concentration due to the application of integrated fertilizer treatments (28-38% increase compared to the control treatment) was significantly higher than the chemical fertilizers treatment (19% increase compared to the control treatment).

Conclusion Based on the results of this research, it was found that the integrated application of organic and inorganic fertilizers has a more positive effect on improving soil fertility in the long term than using them alone. Moreover, the results indicated that the use of cattle manure was more effective than bagasse manure which may be due to its lower carbon to nitrogen ratio (21.3). The integrated use of organic and inorganic fertilizers not only improve soil fertility, but also increases the efficiency of chemical fertilizer use, which reduces the basic chemical fertilizers consumption. Therefore, it is recommended to application of 20 tons of cattle manure every two years + 75% of recommended nitrogen + 50% of the recommended phosphorus and potassium (T3) in the saline-calcareous soils under wheat cultivation in arid and semi-arid climates such as southern of Khuzestan province.

کلیدواژه‌ها [English]

• Saline - calcareous soil
• Sustainable agriculture
• Sugarcane bagasse compost
• Cattle manure