Research Paper
Soil, Water and Plant Relationships
Anahita Hadighanavat; Abdolrahim hooshmand; Parvaneh Tishehzan; Kazem Rangzan; Naser Alemzadeh ansari,
Abstract
Introduction Nowadays, the management of water resources has become one of the major challenges in the world due to recent droughts and water shortages. Therefore, timely and non-destructive monitoring of Water use efficiency (WUE) and yield of plants to screen cultivars with high water use performance ...
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Introduction Nowadays, the management of water resources has become one of the major challenges in the world due to recent droughts and water shortages. Therefore, timely and non-destructive monitoring of Water use efficiency (WUE) and yield of plants to screen cultivars with high water use performance and efficiency and rational allocation of water has become one of the important goals in agriculture. Compared with traditional crop Yield and WUE monitoring and diagnostic tools, hyperspectral remote sensing technology has made it possible to obtain water use efficiency and Yield by taking advantage of large amounts of continuous data on a large scale. Therefore, this study aimed to create a model capable of estimating the WUE and Yield of tomato plants based on hyperspectral remote sensing data by establishing a relationship between common spectral indices and WUE and Yield in greenhouse conditions.Materials and Methods The research was carried out during the growing season of 2021 from January to June at the research greenhouse of the Department of Water and Environmental Engineering, Shahid Chamran University, Ahvaz, Khuzestan Province, The main factor was irrigation treatments in three levels including full irrigation, 20%, and 40% deficit irrigation, and the sub-main factor was silica nanoparticles with concentrations of 0 and 100 mg/lit. The pot experiment plot was laid out in a split plot in a randomized complete design (RCD) with four replications (120 pots in total). Then Tomato yield and WUE under the various treatments, were calculated. Canopy hyperspectral reflectance was measured using a portable spectrometer (ASD FieldSpec 3) operated in the spectral range of 350-2500 nm. The spectral data acquisition was conducted in four stages of plant growth during the growing season and the data were used to calculate spectral indices NWI5, WI3, WI4, NDVI, NDVI, and OSAVI. Then the ability of spectral indices to evaluate the water use efficiency and yield of tomato plants in different irrigation regimes and nanoparticles was investigated. Analysis of variance (ANOVA) was performed on spectral indices and WUE and yield of tomato plants using a split plot design. The PROC GLM method of SAS software (version 9.4, SAS Institute, Inc., Cary, NC, USA) was used for this analysis. Then, in order to compare the averages and whether they have a significant difference with each other at the 0.01 and 0.05 levels, the least significant difference (LSD) test was used.Results and Discussion The results showed that the Water use efficiency (WUE) under deficit irrigation treatments is increased with increasing water stress but the yield of tomato decreases with increase of water stress. In addition, the WUE and yield of tomato increases with increasing the concentration of silica nanoparticles (from 0 to 100 mg/liter). The value of NDVI and OSAVI indices decreased with the increase of water stress, while the value of RDVI, WI3, WI4 and NWI5 indices increased. The amount of NDVI and OSAVI spectral indices in the treatment containing 100 mg/liter nanoparticles was higher than the treatment without nanoparticles. Also, the amount of spectral indices RDVI, WI3, WI4 and NWI5 in nanoparticles with a concentration of 100 mg/liter was lower than the control treatment (zero concentration). The results also showed that the coefficient of determination between the different spectral indices and the WUE and Yield index was 0.55**Furthermore, among the six spectral indices, three spectral indices (NWI5, WI3, and WI4) jointly met most of the criteria used to determine the accuracy of the models for predicting yield and WUEConclusion Maintaining existing water resources through improving irrigation management and increasing water use efficiency and Yield of plants is the main goal for the sustainable development of water agriculture. As a result, rapid and non-destructive monitoring of water use efficiency and Yield is of great importance in improving irrigation management of crops and saving water consumption. significant relationship with yield and WUE index of tomato plants in greenhouse conditions. In conclusion, Spectral indices studied in this research could be useful and non-destructive assessments of the water use efficiency and yield of tomato in greenhouse conditions.Keywords: Deficit Irrigation, Spectral indices, spectroscopy, Tomato Plant, Water use efficiency
Research Paper
Plant Nutrition, Soil Fertility and Fertilizers
Narges sousaraeS; Mojtaba Barani Motlagh; Seyed Alireza Movahedi Naeini
Abstract
Introduction: When the supply of micronutrients needed by the plant is insufficient, not only the yield of the product but also the quality of plant products are affected. Application of organic amendments is one of the ways to increase the nutrients such as zinc uptake by plants for. Biochar can be ...
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Introduction: When the supply of micronutrients needed by the plant is insufficient, not only the yield of the product but also the quality of plant products are affected. Application of organic amendments is one of the ways to increase the nutrients such as zinc uptake by plants for. Biochar can be used as a raw material for the preparation and synthesis of mineral or metal composites due to its high specific surface area, porous structure and oxygen bonding groups on its surface. In these composites, biochar is used as a good porous structure to support and host metals. Biochar can have a significant impact on soil properties, the availability of nutrients, and the dynamics of the nutrients in arid and semi-arid soils, Depending on the feedstock and pyrolysis conditions However, very limited studies have examined biochar use as a nutrient carrier in the synthesis of organic-mineral compounds. Therefore, the present study was done to investigate the efficiency of zinc-enriched biochar pellets using two pre-pyrolysis and post- pyrolysis methods, and their effect on some physiological traits (chlorophyll a, b and total) and bioavailability of zinc in soil and plant.Methods and Materials A zinc deficiency Soil was collected from 0-30 cm depth under arable lands of Seyed Abad located in Azadshahr township, Golestan Province, Iran. To achieve the objectives of this study, a factorial experiment in a completely randomized design with three replications and 18 treatments (54 pots in total) was performed in the greenhouse of Gorgan University of Agricultural Sciences and Natural Resources. Factors included three types of zinc fertilizers (zinc sulphate, zinc-rich biochar prepared using pre-pyrolysis and post-pyrolysis methods) in three levels (0, 10 and 20 mg kg-1 zinc) and foliar spraying (distilled water and 3:1000 zinc). Zinc foliar spraying was done during the 6-10 leaf stage in the early hours of the morning before sunrise. Irrigation and weeding operations were performed manually. At the end of the growing period (vegetative and reproductive), some physiological traits (chlorophyll a, b, total and carotenoid), concentration and zinc uptake in shoots in the two stages of flag leaf emergence and seed maturity, and available concentration of zinc in the soil after wheat plant harvest were measured. The statistical results of the data were analyzed using SAS software and LSD test (at 5% level) was used for comparing the mean values.Results and Discussion: Based on the results, the interaction of type and levels of treatments was significant on all the studied traits at P<0.01, except for carotenoid. The means comparison showed that both zinc-enriched biochar pellets and zinc sulfate increased physiological traits in wheat plants. The highest amount of chlorophyll a, b, and total was obtained with an average of 4.99, 3.36, and 8.35 mg g-1 of fresh weight of the plant from the treatment of a pre-pyrolysis pellet with a concentration of 20 mg kg-1 with zinc sulfate foliar spraying, respectively. The highest zinc uptake in both the flag leaf emergence and seed maturity stages was obtained with an average of 120.33 and 86.62 mg kg-1 of dry weight of the plant from the pre and post-pyrolysis pellet treatment with a concentration of 20 mg/kkg with zinc sulfate foliar spraying, which had an increase of 20 mg kg-1 of zinc sulfate foliar spraying, respectively, equivalent to 27.69 and 30%. The pre-pyrolysis pellet treatment with 20 mg kg-1 zinc and zinc sulfate foliar spraying gave the most zinc extracted with DTPA, at an average of 3.41 mg kg-1. This was compared to the 10 mg kg-1 and 0 mg kg-1 pre-pyrolysis biochar pellet treatments, which gave an average of 2.39 mg kg-1 and 0.92 mg kg-1, respectively, which is an increase of 29.91 and 73.02 percent. The amount of DTPA extractable Zn with the amount of chlorophyll a (r = 0.87**), chlorophyll b (r = 0.81**), total chlorophyll (r = 0.87**), and carotenoids (r = 0.89**) had a positive and significant correlation. The results showed that between DTPA extractable Zn with zinc concentration (r = 0.91**) and zinc uptake (r = 0.90**) in the stage of flag emergence and zinc concentration (r = 0.87**) and zinc uptake (r = 0.86**) in the stage of seed maturity in the wheat plant, there was a positive and significant correlation.Conclusions: In general, the results showed that the positive role of biochar-zinc pellets in increasing the concentration and zinc uptake in wheat plants. Nevertheless, supplemental zinc foliar application with biochar pellets rich in zinc in the amount of 20 mg kg-1 in the form of post-pyrolysis had the greatest effect on the physiological characteristics and Zn bioavailability for wheat plants.
Analytical and Applicable Papers
Plant Nutrition, Soil Fertility and Fertilizers
Fatemeh Foroozesh fard; Shohreh Zivdar; Esmaeil Khaleghi; Edris Shabani
Abstract
Background and Objective:
One of the important aspects of nutrition physiology in fruit trees is the study of seasonal changes in leaf elements, because the seasonal pattern of absorption and distribution of nutrient elements is very important in estimating the fertilizer requirement of fruit orchards. ...
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Background and Objective:
One of the important aspects of nutrition physiology in fruit trees is the study of seasonal changes in leaf elements, because the seasonal pattern of absorption and distribution of nutrient elements is very important in estimating the fertilizer requirement of fruit orchards. The movement of nutrients in fruit crops has been reported a lot, and the plants' need for a specific element is influenced by a specific growth stage in the plant. Research has shown that nutrient accumulation occurs as a continuous process throughout the growing season. In plants, the change process of elements is different in the seasons. By examining the dynamics of elements during different seasons and having the necessary information about these changes, it is possible to examine the relationship between the demand for nutrients during the periods of vegetative and reproductive growth.In Iran, many research has been done on the nutritional requirements of different commercial fruit cultivars, and many studies have reported the dynamics of nutrients in fruit trees during the growing season, but in the case of dates, despite the relative diversity Regarding the cultivars of this plant and Iran's presence in the international competitive markets, there was no report on measuring the dynamics of nutrient elements during the seasons. In the upcoming research, the seasonal evaluation of the concentration of some macronutrients and micronutrients in the leaves of three date varieties has been done.This study was carried out in order to evaluate the seasonal changes in nutrients in the leaves of three date varieties.
Materials and Methods:
This experiment was conducted in the date palm research garden in the northern part of Shahid Chamran University of Ahvaz, in a randomized complete block design with four replications, during 2022 on the leaves of ten years old date palm cultivars (Berhi, Estamaran, and Zahedi). In this experiment, the trend of seasonal changes in macro nutrients (nitrogen, phosphorus, potassium and calcium) and micro nutrients (iron, copper, boron, zinc and manganese) concentration, were investigated throughout the four seasons.After collecting the data, the data was statistically analyzed using SAS 9.1 statistical software, and Duncan's test was used to compare the average data at the level of one and five percent.
Results:
The results showed that the seasons have a significant effect on the concentration of the elements except nitrogen and manganese. Also, the interaction of season and cultivar had a significant effect on the concentration of all nutrients. In terms of macronutrients, Berhi had a better condition, especially during the growing season (spring and summer). The highest difference in terms of element concentration was observed between the winter and growth seasons for date cultivars. The minimum concentration of nitrogen (0.94%) was for Zahedi in spring and winter and the maximum concentration was 2.01% for Barhi (winter). Phosphorus concentration was recorded from the lowest (0.13%) in winter and spring to the highest (0.36%) in summer for Barhi. The range of potassium changes ranged from 1.01% (Estamaran, autumn) to 1.18% (Zahedi, winter). The seasonal changes in calcium concentration was recorded between 0.76 and 0.92%. Also, the range of changes in iron concentration during the year was from 65 to 130 mg/kg and during the growing season to mid-summer from 87 to 117 mg/kg. Bades on the results, leaf iron concentration was estimated to be less than optimal in all seasons. Also the concentration of nitrogen, potassium and copper in leaves decreased during the growth season, especially in summer, and can be due to the consumption of these elements for reproductive growth.
Conclusion:
The concentration of minerals in plants depends on the interaction of several factors including soil, plant species, climate, growth stages, plant production and management and the interaction of elements during absorption. The successful growth of plants and trees requires suitable soil and the presence of sufficient amounts of usable elements and the relationship between them, among which nitrogen, phosphorus and potassium elements are among the main essential elements required by the plant.
The results showed that there is a significant seasonal variation in macronutrients and micronutrients in three date varieties. Also, different seasonal changes patterns were observed among cultivars regarding elements. In such a way, potassium and calcium are more stable than nitrogen and phosphorus during different seasons of the year. Macronutrients (phosphorus and calcium) and micronutrients (zinc, boron and manganese) were at the optimal level. But, the amount of nitrogen, potassium, iron and copper was evaluated as less than the optimal level, which suggests the use of fertilizers containing the mentioned elements at the end of winter..
