هدف از این پژوهش بررسی اثر کاربرد کود نانو کربن دات آهن بر ویژگیهای رشد رویشی گیاه سورگوم در یک خاک آهکی بود. سنتز نانو کربن دات بدون پوشش به روش هیدروترمال و پوششدهی با پلی لاکیک اسید به روش هم رسوبی انجام شد. نتایج آنالیز دستگاههای UV-VIS و FTIR بارگذاری آهن روی سطح کربن داتها را تایید کردند.آزمایش گلخانهای به صورت فاکتوریل در قالب طرح کاملا تصادفی در 3 تکرار انجام شد. فاکتور اول برگپاشی آهن در سه سطح (آب مقطر، سولفات آهن و کربن دات آهن بدون پوشش با غلظت 3 در هزار) و فاکتور دوم کاربرد خاکی کربن دات آهن (با پوشش و بدون پوشش) در 5 سطح که شامل شاهد، کربن دات آهن بدون پوشش و پوششدار هر کدام در دو سطح (mg kg -1 5 و10) بود. طبق نتایج بیشترین تعداد برگ (60/6)، ارتفاع ساقه (cm52/35)، وزن تر ساقه (g plant-1 73/24)، وزن تر برگ (g plant-139/24)، وزن خشک برگ (g plant-137/5) و وزن خشک ساقه (g plant-173/4)، غلظت آهن در ساقه (mg kg-1211) و برگ (mg kg-1 186) مربوط به اثر متقابل تیمار خاکی کربن دات آهن بدون پوشش با سطح mg kg -1 10 با محلولپاشی کربن دات (غلظتg lit-13) و بیشترین غلظت آهن خاک (mg kg-1 92/5) مربوط به تیمار خاکی کربن دات آهن پوششدارmg kg -1 10 محلولپاشی شده با کربن دات (غلظت 3 در هزار) بود. بنابراین هر دو نوع کود جهت کشت سورگوم و تامین نیاز کودی آن مناسبند.
عنوان مقاله [English]
Investigating the effect of iron nano carbon dot fertilizer application on vegetative growth parameters of sorghum in a calcareous soil
Nanotechnology involves nanomaterials that are less than 100 nm as an interdisciplinary and pioneering technology has solved many problems in the fields of agriculture. The use of iron nano-fertilizers in order to control the release of nutrients can achieve sustainable agriculture by reducing the consumption of chemical fertilizers. Nano CDs (carbon dots) are a new system or carbon material between molecule and condensed solid, which gathers the characteristics of nano effect, surface functional groups and carbon elements. Therefore, it shows three basic functions of optics, chemistry and biology, and has multiple functions and applications. In addition, the abundant hydrophilic functional groups on the surface of CDs, small size and other structural characteristics made it show great advantages in promoting crop growth and enhancing photosynthesis and stress resistance. The aim of this study was to investigate the effect of iron nano carbon dot fertilizer application on vegetative growth parameters of sorghum plant in a calcareous soil.
Materials and Methods
Iron nano carbon dots were synthesized with lemon juice (carbon source), ethylenediamine and iron sulfate (iron source) by hydrothermal method. Coating of nanoparticles with poly lactic acid was done by co-precipitation method. Characterization of iron nano carbon-dots to confirm the successful loading of iron on the surface of carbon dots and also successful coating was done by UV-VIS, EDAX, FTIR, TEM and SEM device analyses. Some chemical properties of nanocarbon dots such as pH, electrical conductivity and salinity index were measured. Sorghum cultivation was done in the greenhouse of Isfahan agricultural and natural resources research center with a factorial design in 3 replications. The first factor was foliar spraying in three levels (distilled water, iron sulfate and no coating iron carbon dot with a concentration of 3 per thousand) and the second factor was soil application of iron carbon dot (with and no coating) in 5 levels including iron carbon dot, no coating and coated each in two levels (5 and 10 mg Fe kg-1 soil). Foliar spraying of sorghum at the eight-leaf stage was carried out by iron carbon dot and iron sulfate with a concentration of 3 parts per thousand. After the plant growth period (4 months), growth parameters such as the number of leaves, stem height, stem diameter, and fresh and dry weight of stem and leaves were measured. Also, the concentration of iron in plants and soil was also measured.
Results and Discussion
No coating iron nano carbon dots had 4.98% total iron and polylactic acid coated carbon dots had 1% iron. According to the successful results on carbon dots, they were confirmed with UV-VIS and FTIR devices. Based on the results of leaf number (6/60), stem height (35.52cm), stem fresh weight (24.73 g plant-1), leaf fresh weight (24.39 g plant-1), leaf dry weight (5.37 g plant-1) and the dry weight of the stem (4.73 g plant-1) was related to the interaction effect of no coating iron carbon dot soil treatment with a level of mg Fe kg-1 soil 1 with carbon dot foliar spraying (concentration 3 per thousand). The highest amount of iron in the stem (211 mg kg-1) and leaf (186 mg kg-1) is related to the carbon dot iron soil treatment with a level of 10 mg Fe kg-1 soil and the highest amount in the soil (5.92 mg kg-1). It was related to the interaction effect of iron carbon dot soil treatment coated with polylactic acid polymer (level of 10 mg Fe kg-1 soil) with carbon dot foliar spraying (concentration 3 parts per thousand).
Among the foliar treatments with iron carbon dot and ferrous sulfate heptahydrate, the treatments that were in the group of foliar treatments with nano carbon dot iron had the most positive performance. The treatment of no coating iron carbon dot and then the treatment of iron carbon dot coated with polylactic acid, with level of 10 mg Fe kg-1 soil which simultaneously applied soil and foliar application with carbon dot with concentration 3 parts per thousand showed the best performance. Therefore, these two types of synthesized nano fertilizers are suitable for sorghum cultivation and can be used as a type of iron fertilizer for agricultural purposes.
Keywords: Iron nano carbon dot, nano carbon dot coating, sorghum, foliar spraying