كليدواژه :
كود زيستي , كود شيميايي , عملكرد , ذرت
چكيده فارسي :
به منظور مطالعه‌ي اثر كاربرد همگام كودهاي بيولوژيكي، شيميايي و همچنين روش كاربرد آن بر عملكرد ذرت دانه اي رقم 704 ، آزمايشي در سال 94-1393 در بابل به‌صورت فاكتوريل در قالب طرح بلوك كامل تصادفي با 3 تكرار انجام شد. تيمارها شامل تلفيق كودهاي زيستي و شيميايي در 5 سطح (كود شيميايي، كود شيميايي + كود زيستي، 50 % كود شيميايي + كود زيستي، 25 % كود شيميايي + كود زيستي ، كود زيستي) به عنوان فاكتور اول و روش كاربرد كود زيستي در 3 سطح ) بذرمال، آبياري، بذرمال+ آبياري (به عنوان فاكتور دوم بود. نتايج آزمايش نشان داد كه عملكرد و اجزاء عملكرد تحت تاثير مقادير مختلف كود شيميايي و كود زيستي معني دار گرديد. بيشترين عملكرد دانه در تيمار كود شيميايي+ كود زيستي (11/973 تن در هكتار) و كمترين عملكرد دانه در تيمار كود زيستي (6/023 تن در هكتار) به دست آمد. همچنين بيشترين و كمترين شاخص برداشت به ترتيب در تيمار كود شيميايي و كود زيستي مشاهده شد. بيشترين تعداد دانه در رديف بلال (41/3) مربوط به تيمار (50 كود شيميايي + كود بيولوژيك) بود. بيشترين وزن هزار دانه در تيمار (كودشيميايي+ كود بيولوژيك) با مقدار 394 گرم بود. روش كاربرد كود بيولوژيك تاثير معني داري بر روي وزن هزار دانه نداشت با اين حال بيشترين وزن هزار دانه در تيمار كاربرد كود به روش بذرمال+آبياري با مقدار 346/67 گرم بود. نتايج نشان داد، كاربرد تلفيقي كودها ضمن افزايش عملكرد ذرت باعث كاهش قابل توجه مصرف كودهاي شيميايي ميشود.
چكيده لاتين :
improving yield quality and quantity. When feeding plants, it is necessary not only to provide them with adequate nutritional elements but also there is a great need to maintain the balance of nutrients in plants. Over the years with the indiscriminate use of chemical fertilizers, especially nitrogen and phosphorus, and failure to comply with nutrient balance, considerable damage has been inflicted upon agricultural lands (Tohidi Moghadam et al., 2007). Soil beneficial microorganisms are one of the determining factors for plant health and soil productivity, as they are involved in several key processes, such as biological control of pathogens, nutrient rotation and seedling establishment (Rosas et al., 2008). Biological fertilizer is a substance which contains microorganisms that, when applied to seed, plant surface or soil, occupies rhizosphere or enters inside plant, thereby stimulating growth through supplying plants with some essential nutrients. The aim of this investigation was to find a way to decrease the consumption of chemical fertilizers and increase the availability of soil nutrients as well as to explore the possibility of the application of biofertilizers as replacement or complementary for nitrogen and phosphorus fertilizers. Materials and Methods: The experiment was carried out as factorial based on completely randomized block design with three replications using grain corn (SC.704) at a farm in Amol in the crop year 2015-2016. Two biological fertilizers, nitroxin containing nitrogen-fixing bacteria, such as Pseudomonas, Azospirillum and Azotobacter) and phosphorus bacteria fertilizer (Bacillus coagulans) were respectively used to supply the corn plant with nitrogen and phosphorus. The fertilizer treatments included: chemical fertilizers (N and P) (A1), chemical and biological fertilizers (A2), 50 % recommended chemical fertilizer rate and biological fertilizer (A3), 25 % recommended chemical fertilizer rate and biological fertilizer (A4) and full application of biological fertilizers (nitroxin and phosphorus bacteria) (A5). The second factor was three application methods consisting of coating of seed with biofertilizers at the sowing time (B1), application of biofertilizers along with irrigation (biofertigation) (post-emergence application when the corn had 8 leaves) (B2) and the seed-coating treatment in combination with biofertigation (50 % of the recommended amount of biofertilizer in seed coating and the remaining 50 % when the corn had 8 leaves, respectively) (B3). The statistical analysis was conducted using SAS software and means were compared by Duncan test at 5% probability level. Results and Discussion: The results showed that the corn yield and yield components were signficantly affected by different rates of chemical and biological fertilizers (P≤1%), however, the application method of biological fertilizer had no significant impact on the measured traits. The greatest corn grain yield (11.97 t.ha- 1) was obtained from A2 treatemnt (chemical fertilizer +biofertilizer). A5 treatment (application of chemical fertilizer) gave the lowest yield of 6.02 t.ha-1. The highest number of grains per cob (41.3) was achieved by the application of 50% chemical fertilizer + biofertilizer. The highest 1000-seed weight (394 gr) was associated with the treatment A2. Gholami and Biari (2007) reported that inoculation with biofertilizer together with use of chemical fertilizer led to a considerable increase in corn 1000-seed weight. The use of biofertilizer, especially in combination with chemical fertilizer resulted in a significant increase of cob weigh so that the highest cob weight (14.07 t.ha-1) was observed in A2 treatment, though it was not statistically different from A1 and A3 treatments at 5% probability level. The sole application of biofertilizer produced the lowest weight of cob (6.51 t.ha-1). Treatment A4 exhibited the highest biological yield of 21.23 t.ha-1 followed by A3 (20.67 t.ha-1) and A1 (19.35 t.ha-1) treatments, which fell within the same statistical group. The sole use of chemical fertilizer produced the highest harvest index (59.28) and the lowest value for this parameter (40.84) was detected in the treatment where biofertilizer was applied alone. No statistical differences existed for harvest index between different fertilizer application methods, however, biofertigation +coating of corn seed with biofertilizer (B3) resulted in less harvest index than B1 and B2 treatments. Conclusion: Our results indicated that the combined application of chemical and biological fertilizers resulted in a significant reduction in the consumption of chemical fertilizers, while increasing corn yield.
