Plant Nutrition, Soil Fertility and Fertilizers
Fatemeh Meskini-Vishkaee; Ali Reza JAfarnejadi
Abstract
Introduction In Iran, salinity is a pervasive and limiting Factor of agricultural sustainable production. Plants in saline conditions are exposed to limited absorption of nutrients, water and toxicity of some elements and subsequently, their yield will be affected by salinity. Moreover, dust storms in ...
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Introduction In Iran, salinity is a pervasive and limiting Factor of agricultural sustainable production. Plants in saline conditions are exposed to limited absorption of nutrients, water and toxicity of some elements and subsequently, their yield will be affected by salinity. Moreover, dust storms in arid and semi-arid climates are one of the most important environmental and pollution problems, as they directly and indirectly reduced the quality and quantity of agricultural products. Dust occurrence frequency in the country, especially in the western and southwestern regions increased in the last decades. Hence, increased dust occurrence frequency and intensity during the growth period of agricultural crops is one of the most substantial risks in agricultural sustainable production in Khuzestan province. Thus, the aim of the study was to investigate the effects of dust occurrence and farm management practices applied to reduce the effects of this stress on wheat yield indices as a strategic agricultural product in Khuzestan province. Materials and Methods This study was carried out in Khuzestan province in a calcareous and saline soil with clay loam texture under wheat cultivation (Barat cultivar) as a split plat experiment in a randomized complete blocks design with three replications. Two agricultural farm managements included 1) the custom of the farmer (traditional farming) and 2) nutrition management (soil test, soil balanced and complementary nutrition) based on plant phenological growth stages. In each farm management operation, four leaf washing treatments including 1) without leaf washing, 2) leaf washing after the occurrence of dust phenomenon in the tillering stage, 3) leaf washing after the occurrence of dust phenomenon in the booting stage and 4) leaf washing after the occurrence of dust phenomenon in both the tillering and booting stages, in plots with an area of 20 m2 were applied in three replicates. At the end of the growth season, wheat yield indices involved thousand kernel weight, number of grains per spike, biomass weight, grain yield and the number of tillers per square meter in different treatments were determined. SAS v.9.1 statistical software and Duncan's multiple range test were used to compare the means of the studied treatments.Results and Discussion The results showed that the highest wheat grain yield was observed in the treatment of balanced nutrition management and leaf washing after dust occurrence at two wheat growth stages (5180 kg ha-1), while the least wheat grain yield was in the traditional management and no leaf washing treatment (2830 kg ha-1). The interactions of farm management practices and different leaf washing treatments on biomass, grain yield, harvest index, thousand kernel weight and number of tillers per square meter were significant (p< 0.01). In the traditional management of the farmer, using the plant leaves washing at only one wheat growth stage after the occurrence of dust caused about 30% increase in wheat grain yield on average (24 and 35% increase in grain yield as a result of leaf washing after dust, respectively, in the tillering and booting stages). While in the traditional management and leaf washing at both two stages of wheat growth, it increased the wheat grain yield by 43%. In addition, the results showed that by using balanced nutrition management without leaf washing, wheat grain yield and harvest index increased by 10 and 9%, respectively. Application of balanced nutrition and leaf washing after the dust occurrence at both two wheat growth stages (tillering and booting) caused 32, 59, 21 and 11% increase in biomass, grain yield, harvest index and thousand kernel weight of wheat.Conclusion Based on the results of this research, it was found that the use of different management operations in the farms, such as balanced nutrition of the crop based on the plant growth phenological stages and the leaves washing after the occurrence of dust, can significantly reduce the damage of wheat yield caused by the occurrence of dust. However, it should be noted that despite the positive and significant effect of washing the plant leaf surface after the occurrence of dust phenomenon on reducing wheat yield damage, the time of leaves washing application is very important. Because if immediately after washing the leaf surface of the plant, the dust phenomenon occurs again, the wetness of the plant leaf surface causes more dust particles to deposit on it and the damage caused by dust on wheat yield indices increases.All right reserved.
Ali Reza JAfarnejadi; Fatemeh Meskini-Vishkaee; Mohammad Hadi Mousavi Fazl; Gh. Lotfali Ayeneh; Leila Behbahani
Abstract
abstractIntroduction In Iran, salinity is a pervasive and limiting Factor of agricultural sustainable production. Plants in saline conditions are exposed to limited absorption of nutrients, water and toxicity of some elements and subsequently, their yield will be affected by salinity. Moreover, being ...
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abstractIntroduction In Iran, salinity is a pervasive and limiting Factor of agricultural sustainable production. Plants in saline conditions are exposed to limited absorption of nutrients, water and toxicity of some elements and subsequently, their yield will be affected by salinity. Moreover, being calcareous, the salinity of soil and irrigation water, low organic matter in the country's arable soils, and excessive consumption of phosphate fertilizers cause a lack of available nutrients for the plant uptake. As regards more than three billion people in the world suffer from a lack of micro nutrients, the bio-enrichment in strategic products such as wheat is necessary.Materials and Methods This study was carried out in Khuzestan province in a calcareous and saline soil with silty clay texture under wheat cultivation as a factorial experiment in a randomized complete blocks design with three replications. Factors included four levels of zinc (zero, 30, 60 and 120 kilograms per hectare of zinc sulfate) and the four levels of iron (zero, 2.5, 5, 7.5 kilograms per hectare of Fe- EDDHA). Zinc fertilizer treatments were used as application in soil and simultaneously with basic fertilizers (phosphorus and potassium fertilizers). While, iron fertilizer treatments were applied as irrigation fertilizer during wheat tillering stage. At the end of the growth season, wheat yield components (1000-seed weight, number of grains per spike, biomass weight, grain yield, number of tillers per square meter) and quality characteristics including hectoliters, seedling number, protein percentage, grain hardness and moisture content in different treatments were determined. MSTAT-C statistical software and Duncan's multiple range test were used to compare the means of the studied treatments.Results and Discussion The results showed that the interactions of zinc and iron on 1000-grain weight, number of grains per panicle and number of tillers and simple effects of zinc on total yield were significant (p< 0.01). The highest wheat grain yield was obtained in the treatment of 120 kilograms per hectare of Zn and 2.5 kilograms per hectare of iron and was equal to 6723 kilograms per hectare. The results showed that increasing one element alone had a negative effect on the number of plants per square meter. So that the lowest number of tillers per square meter (489 tillers per square meter) was observed when 60 kilograms per hectare of zinc fertilizer was consumed without iron fertilizer application. In other words, the imbalance in the amount of nutrients caused a significant reduction in the number of plants per square meter. Although the role of iron in yield and yield components of wheat in saline conditions was less than the element zinc, but the combined use of zinc and iron in a certain ratio had a positive effect on the yield components of wheat. Despite the less effect of iron application than zinc on wheat yield and yield components in saline conditions, the combined application of zinc and iron in a certain ratio had a positive effect on the wheat yield components. Combined and separate application of iron and zinc had no significant effect on wheat grain quality indicators including hectoliters, hardness and moisture. While the application of the most value of zinc caused a significant decrease in the wheat grain zeleny index. Higher levels of zinc fertilizer reduced the zeleny number of wheat grain, but the results showed that iron fertilizer levels followed the opposite trend rather than the element zinc. The least protein content (12.8%) was obtained in the treatment of 120 kg zinc fertilizer per hectare, which showed a statistically significant difference with the control treatment. Based on economic analysis, the application of 30 kg of zinc fertilizer per hectare, 2.5 kg of iron fertilizer per hectare and the combined application of both zinc and iron fertilizers resulted in a benefit-to-cost ratio of 2.3, 3.1 and 2, respectively.Conclusion Based on the economic analysis of treatments, their effect on qualitative and quantitative yield of wheat and the role of these micronutrients in human health, application of 30 kg ha-1 Zn fertilizer (as application in soil) and 2.5 kg ha-1 Fe fertilizer (as Irrigation fertilizer) in the wheat tillering stage was suggested in saline soil and climate conditions of khuzestan province.All right reserved. All right reserved. All right reserved.
A. R. Jafarnejadi; S. M. H. Mousavifazl; M. javadzadeh
Abstract
Introduction In spite of problems in providing timely and adequate water supply, the inefficient water use efficiency in agriculture as the most important consumer of freshwater is one of the most important challenges and issues in the agriculture. The knowledge of soil physical properties and water ...
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Introduction In spite of problems in providing timely and adequate water supply, the inefficient water use efficiency in agriculture as the most important consumer of freshwater is one of the most important challenges and issues in the agriculture. The knowledge of soil physical properties and water retention have main rolled on soil water application management. This research was conducted to determine the soil physical and chemical properties affecting the soil water retention capacity in calcareous soils series in Khuzestan province. Materials and Methods From the nine dominant series in the different regions, five disturbed soil samples and the same number of undisturbed soils were collected from 0-20 cm depth. Soil physical properties including soil texture, bulk density were measured. Moreover, soil water characteristic curve was measured at five points (0, 330, 1000, 5000 and 15000 cm) using pressure plate and pressure membrane devices. The van Genuchten equation was fitted on the measured soil water characteristic curve data. In addition to soil physical and hydrological properties, soil salinity as electrical conductivity (EC), pH and lime (TNV) were also measured. Results and Discussion The results showed that the soil pH varied in the range of 7.1 - 7.6, EC variation range was 2.43 - 47 dS m-1, sand, silt and clay contents varied in ranges of 18 - 40%, 32 - 50% and 20 - 44 %, respectively, TNV was 48 – 60 % and the values of soil bulk density were in the range of 1.14 - 1.52 g cm-3. The studied soils were calcareous (TNV value of all studied series was more than 45 %) and had moderate to heavy texture including loam (55 % of studied soil series), silty clay loam (23 %), clay loam (11 %) and clay (3 %). The water content at field capacity (corresponding of soil suction of 330 cm) and permanent wilting point (corresponding of soil suction of 15000 cm) varied from 32 to 56 % and 16 to 26 %, respectively. There are significant correlation between clay content with the soil moisture at both field capacity and permanent wilting point. The most salinity was observed in south east of Ahvaz (loam), south Ahvaz (loam), Khoramshahr 2 (clay) and Khoramshahr 1 (loam) series. The values of soil available water in studied calcareous series were varied as Khorramshahr 2 (0.30 cm3 cm-3) > Ahvaz-Hamidiyeh (0.22 cm3 cm-3) > Khorramshahr 1 (0.189 cm3 cm-3) > Ramhormoz-Rustamabad 1 (0.177 cm3 cm-3) > Ramhormoz-Bazidi (0.165 cm3 cm-3) > South of Ahwaz (0.16 cm3 cm-3) > South east of Ahwaz (0.134 cm3 cm-3) > Ramhormoz- Rustam Abad 2 (0.119 cm3 cm-3) > Shadegan (0.102 cm3 cm-3). The results showed that van Genuchten equation had suitable fit on studied soils of dominant calcareous series. The studied soil samples from the south of Ahvaz with the highest bulk density (1.55 g cm-3) and high salinity (33.5 dS m-1) had the highest value of the van-Genuchten parameter (n) which indicates more uniform distribution of the soil pore volume. In spite of the high ability of Khorramshahr 2 series in soil water retention, based on the coefficients of van Genuchten equation and measured soil water characteristic curve, it can be argued that this soil probably has severe aeration limitation. Conclusion The result showed that salinity and bulk density were important properties that affect the ability of soil water retention and availability in the studied soil series. Extensive water retention capacity in the soil (10 to 30 %) indicates the need for different irrigation management operations in each of the studied soil series. The highest value of soil densities were observed in south of Ahvaz, Ramhormoz-Bazidi and Khorramshahr series, indicating soil degradation in studied areas due to inappropriate cultivation management practices. Moreover, the results showed that the experimental parameters of the van Genuchten equation have a physical concept and can be found useful information on the soil ability to water retention and some other soil physical properties. The results of this research confirmed that there is a significant difference in the ability of soil water retention in the dominant calcareous soils series of Khuzestan province which indicates the necessity of proper understanding of soil hydraulic properties for irrigation management in farms, increasing water use efficiency.
