Soil and Plant Interactions

fa تأثیر ترکیب یونی محلول‌های غذایی بر رشد، غلظت عناصر غذایی پرمصرف و عملکرد دو رقم ذرت علوفه‌ای (.Zea mays L) در کشت بدون خاک The Effect of Ionic Composition of The Nutrient Solutions on Growth, Macronutrients Concentration and Yield of Two Fodder Maize (Zea mays L.) Cultivars in Soilless Culture روابط خاک (بستر رشد) و گياه در كشت‌هاي گلخانه‌اي Soil (growth medium) and plant relations in greenhouse culture كاربردي Applicable دانسته‌های اندکی در مورد ترکیب یونی محلول غذایی مناسب برای تولید ذرت علوفه‌ای در کشت بدون خاک وجود دارد. بنابراین هدف این پژوهش، انتخاب یک محلول غذایی پایه برای تولید ذرت علوفه‌ای در کشت بدون خاک بود. به این منظور یک آزمایش گلدانی با دو عامل نوع محلول غذایی و نوع رقم ذرت علوفه‌ای به‌صورت فاکتوریل در قالب طرح بلوک‌های کامل تصادفی با چهار تکـرار در گلخانه پژوهشی دانشگاه شهرکرد انجام شد. محلول‌های غذایی مورد استفاده عبارت بودند از: 1) محلول غذایی تمام قدرت هوگلند و آرنون، 2) محلول غذایی نیم‌قدرت هوگلند و آرنون، 3) محلول غذایی باری و میلر، 4) محلول غذایی الکساندر و همکاران، و 5) محلول غذایی رواکورا. همچنین ارقام ذرت علوفه‌ای شامل هیبرید سینگل‌کراس 704 و سینگل‌کراس 410 بودند. نتایج نشان داد در هر دو رقم، بیش‌ترین غلظت نیتروژن و فسفر برگ، ساقه و ریشه در گیاهان تغذیه‌شده با محلول غذایی رواکورا مشاهده شد. کاربرد محلول غذایی الکساندر و همکاران منجر به افزایش معنی‌دار غلظت پتاسیم برگ، ساقه و ریشه در مقایسه با سایر محلول‌های غذایی شد. تأمین بهینه عناصر غذایی مورد نیاز ذرت توسط محلول غذایی رواکورا منجر به افزایش معنی‌دار ارتفاع گیاه، قطر ساقه، سطح برگ و شاخص سبزینگی برگ شد. در هر دو رقم ذرت بیش‌ترین وزن تازه و خشک شاخساره و کارایی مصرف آب با کاربرد محلول غذایی رواکورا حاصل شد. بر مبنای نتایج این آزمایش، کاربرد محلول غذایی رواکورا برای کشت هر دو رقم ذرت (سینگل‌کراس 704 و سینگل‌کراس 410) در کشت بدون خاک به‌منظور تولید علوفه در شرایط مشابه این پژوهش پیشنهاد می‌شود. Abstract Little information is available concerning ionic composition of the suitable nutrient solution for fodder maize production in soilless culture. Therefore, the aim of this study was to select a basic nutrient solution for production of fodder maize in soilless culture. A pot experiment was carried out as a factorial in a randomized complete block design with two factors of nutrient solutions and cultivar types and four replications in the research greenhouse of Shahrekord University. The nutrient solutions were: 1) full-strength Hoagland and Arnon, 2) half-strength Hoagland and Arnon, 3) Barry and Miller, 4) Alexander et al., and 5) Ruakura. Two maize cultivars of single cross hybrid 704 and single cross 410 were used. The results indicated that in both maize cultivars, the highest concentrations of nitrogen and phosphorus in leaf, stem and root were observed in the plants nourished with Ruakura nutrient solution. The application of Alexander et al. nutrient solution led to significant increase in potassium concentrations in leaf, stem, and root compared to other nutrient solutions. Optimum supply of nutrient requirements of maize with Ruakura nutrient solution resulted in significant increase in plant height, stem diameter, leaf area and leaf greenness index. In both maize cultivars, the highest shoot fresh and dry weights as well as water use efficiency were obtained in the plants nourished with Ruakura nutrient solution. Based on the results, application of Ruakura nutrient solution is suggested for the cultivation of both maize cultivars (i.e., single cross hybrid 704 and single cross 410) in soilless culture in order to produce fodder under the conditions similar to this study. Background and Objective: Sustainable fodder production for feeding livestock is regarded as one of the challenges of agricultural sector in the recent years. One of the recently used methods for fodder production is hydroponic system (i.e., soilless culture). In soilless culture, all essential nutrients are supplied to the plant’s roots by nutrient solution. The factors such as plant species and cultivar type, the type of hydroponic system (open and closed), plant growth stage, edible part of the plant, growing season and weather conditions (temperature, light intensity and day length) are effective in choosing a suitable nutrient solution (1). Therefore, choosing the optimum nutrient solution is the fundamental key to success in this cultivation method. Considering the lack of sufficient information about ionic composition of the nutrient solution for production of fodder maize in soilless culture, the present study was carried out to select optimum nutrient solution for its production at the greenhouse conditions of Shahrekord University. Methods: A factorial experiment using randomized complete block design was conducted with the two factors of nutrient solutions and maize cultivars (i.e., single cross hybrid 704 and single cross 410) and four replications in hydroponic culture at the research greenhouse of Shahrekord University. The nutrient solutions were: 1) full-strength Hoagland and Arnon, 2) half-strength Hoagland and Arnon, 3) Barry and Miller, 4) Alexander et al., and 5) Ruakura. Maize seedlings were transferred to 10 liter plastic pots containing perlite (with particle size of 0.5 to 5 mm) and were manually fertigated with nutrient solutions on a daily basis. At the end of tasseling stage, plant height, stem diameter, leaf greenness index and leaf area were measured. Then, plants were harvested and fresh weights of root, stem and leaf were determined. Plant biomasses were dried and dry weights of root, stem and leaf were measured. Plant samples were ground and the concentrations of N, P and K were measured in each part. In addition, water use efficiency was calculated by dividing shoot dry weight to the volume of the applied nutrient solution. Analysis of variance was performed using the SAS software. Means comparison was conducted using Duncan's multi-range test at p < 0.05. Results: The results showed that the highest concentrations of nitrogen in leaf (31.5 g kg-1) and stem (21.7 g kg-1) were observed in the plants nourished with Ruakura nutrient solution in single cross hybrid 704. The root nitrogen concentration had a trend similar to the values in leaf and stem, and reached the highest level in the plants fed with Ruakura nutrient solution. In both maize cultivars, the highest concentration of phosphorus in leaf was observed in the plants fertigated with Ruakura nutrient solution. However, the highest concentrations of potassium in leaf, stem and root were recorded in the plants fed with Alexander et al., nutrient solution. Application of Ruakura nutrient solution led to an increase in the plant height, stem diameter, leaf area and leaf greenness index in both maize cultivars. The results revealed that the highest shoot fresh weights in single cross hybrid 704 (1102 g plant-1) and single cross 410 (1076 g plant-1) were obtained in the plants nourished with Ruakura nutrient solution. This nutrient solution resulted in the highest water use efficiency in both maize cultivars. Conclusions: The results demonstrated that using Ruakura nutrient solution through optimal supply of the nutrients required for maize production in soilless culture, increased the plant height, stem diameter, leaf area and leaf greenness index in both maize cultivars. This increase led to the highest fresh and dry weights of shoot and root as well as greatest water use efficiency in maize plants. Consequently, in both maize cultivars (i.e., single cross hybrid 704 and single cross 410), application of Ruakura nutrient solution can be recommended for fodder production in the soilless culture under the conditions of the present study. References: <div style="text-align:justify">1. Arzani, A., 2007. Commercial and Home Hydroponics. Isfahan University of Technology, Isfahan. (In Persian)</div>   آب‌کشت, تغذیه متعادل, شاخص‌های رشد رویشی, کارایی مصرف آب. Hydroponic, Balanced nutrition, Vegetative growth indices, Water use efficiency. 31 51 http://jspi.iut.ac.ir/browse.php?a_code=A-10-2075-1&slc_lang=fa&sid=1 M. Ghorbani مریم قربانی m.ghorbani.uoz@gmail.com Yes Soil Science and Engineering Department, Faculty of Agriculture, Shahrekord University. گروه علوم و مهندسی خاک، دانشکده کشاورزی، دانشگاه شهرکرد Sh. Kiani شهرام کیانی shkiani2002@yahoo.com No Soil Science and Engineering Department, Faculty of Agriculture, Shahrekord University. گروه علوم و مهندسی خاک، دانشکده کشاورزی، دانشگاه شهرکرد A. Moharrery علی محرری No Animal Science Department, Faculty of Agriculture, Shahrekord University. گروه علوم دامی، دانشکده کشاورزی، دانشگاه شهرکرد S. Fallah سینا فلاح falah1357@yahoo.com No Agronomy Department, Faculty of Agriculture, Shahrekord University. گروه زراعت، دانشکده کشاورزی، دانشگاه شهرکرد