واکنش عملکرد ارقام گلرنگ(carthamus tinctorius l.) به کاربرد فسفر وشاخص‌های کارایی آن

به‌منظور بررسی تاثیر فسفر بر عملکرد دانه و شاخص‌های کارایی فسفر در ارقام گلرنگ، این آزمایش به‌‌صورت فاکتوریل در قالب طرح بلوک‌های کامل تصادفی با دو عامل الف) فسفر در پنج سطح صفر، 50، 100، 150و 200 کیلوگرم در هکتار از منبع سوپر فسفات تریپل و ب) ارقام گلدشت و صفه، در مرکز تحقیقات و آموزش کشاورزی صفی‌آباد دزفول طی دو سال (1391 و 1393)، اجرا گردید. نتایج نشان داد که برهمکنش تیمارها بر تعداد طبق بارور در متر مربع و تعداد دانه در طبق، معنی‌دار بود. در هر دو رقم با افزایش مصرف فسفر، صفات مذکور افزایش معنی‌داری یافت. بیشترین تعداد طبق بارور (252 عدد)، و تعداد دانه در طبق (23.17 عدد)، در سطح 150 کیلوگرم فسفر در هکتار به‌دست آمد. برهمکنش سال در فسفر بر وزن هزار دانه و عملکرد دانه و برهمکنش سال در رقم بر وزن هزار دانه معنی‌دار گردید. بیشترین وزن هزار دانه(42.41 گرم)، و عملکرد دانه (2184 کیلوگرم در هکتار)، با مصرف 100 کیلوگرم فسفر در هکتار حاصل گردید. رقم صفه با عملکرد دانه و روغن، 1979 و 599 کیلوگرم در هکتار، برتر از رقم گلدشت بود. مصرف فسفر باعث کاهش معنی‌دار کارایی مصرف (69 درصد)، و جذب (85 درصد)، گردید. لذا، با توجه به بیشترین نسبت فایده به هزینه (35.51)؛ مصرف 50 کیلوگرم فسفر با بیشترین شاخص کارایی مصرف و جذب (به‌ترتیب 0.7 و 0.69 کیلوگرم در کیلوگرم)، و نیز انتخاب رقم صفه، قابل توصیه می‌باشد.

Yield of Safflower (Carthamus tinctorius L.) Cultivars in Response to Phosphorus Application and Its Efficiency Indices

Introduction: Phosphorus is the third most important nutrient in crop production after nitrogen and potassium. It is involved in all biochemical processes, energetic compounds, and energy transfer mechanisms. Phosphorus participates in the cellular proteins and cell membrane and nucleic acids. In addition, this element is essential for seed formation and root development. Also, this element recovery in the first year of application estimates to be 8 to 30%, and after 30 years rarely reaches to 50% and its rest is stabilized in the soil and accumulates inaccessibly for most plants. Therefore, in the last two decades, scientists have used various methods to improve the efficiency of phosphorus, including the selection and genetic modification of plants and the adopting agricultural practices such as determining the optimal amount of phosphorus, the right time and method of application and the right fertilizer source. In addition, due to the growing trend of vegetable oil consumption and the high cost of supplying the required oil through imports, the purpose of this study was to determine the optimal rate of phosphorus and selecting the appropriate efficient cultivar in order to extend oilseed crops cultivation.Materials and Methods: In order to study the response of safflower cultivars (Carthamus tinctorius L.), to phosphorus rates and their efficiency indices, a factorial experiment was conducted in a randomized complete block design with three replications during 201213 and 201415 at Safiabad Agricultural Research Center of Dezful, Khuzestan, Iran. The first factor included five phosphorus levels (0, 50,100, 150 and 200 kg ha1 as Triple Super Phosphate TSP), and the second factor included two cultivars (Goldasht and Soffeh). Safflower seeds were planted by setting up a sugar beet planter, in a row with a distance of 50 cm between rows and a distance of 5 cm between plants. Urea and potassium sulfate were uses at 300 and 100 kg ha1, respectively. Onethird of nitrogen and all phosphorus and potassium were used pre planting. The rest of urea fertilizer was applied as top dressing in two equal splitting rates (beginning of stem and early flowering stages). Before harvesting in each replication, the number of fertile heads per square meter (in three boxes of one square meter per plot), and the number of full grains (counting full grains in 20 heads), and after harvesting the weight of 1000 seeds (with three times counts were calculated in three random groups of 1000 seeds per plot). Finally, number of fertile heads per square meter, number of seeds per heads, 1000seed weight, seed and oil yields, seed phosphorus uptake, and phosphorus efficiency indices were measured.Results and Discussion: The results showed that the interaction of treatments was significant on the number of fertile heads per square meter and number of seeds per head. In both cultivars, with increasing phosphorus application, the mentioned traits increased significantly. The highest number of fertile heads (252 pieces), and the number of seeds per head (23.17 pieces), were obtained at the level of 150 kg phosphorus ha1. The interaction between year and phosphorus on 1000seed weight and seed yield and the interaction between year and cultivar on 1000seed weight were significant. The highest 1000seed weight (42.41 g), and seed yield (2184 kg ha1), were obtained by application of 100 kg phosphorus ha1. Seed and oil yields of Soffeh cultivar (1979 and 599 kg ha1, respectively), was superior to Goldasht cultivar. Also, the results showed that Goldasht cultivar had higher utilization efficiency (248 kg kg1), compared to Soffeh cultivar (218 kg kg1). Phosphorus application significantly reduced use and uptake efficiency indices (69% and 85%, respectively). So that the treatment without phosphorus application had the highest use and uptake efficiency (1 kg kg1). The difference between use and uptake efficiency at the level of 50 kg phosphorus ha1 with other phosphorus levels was about 19% and 25%, respectively.Conclusions: In general, due to the highest benefittocost ratio (35.51) and use and uptake efficiency indices (0.69 and 0.7 kg .kg1, respectively), application of 50 kg ha1 of phosphorus fertilizer and Soffeh cultivar is recommended.