نوع مقاله : مقاله پژوهشی
1 مربی بخش تحقیقات اصلاح و تهیه نهال و بذر، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی کهگیلویه و بویراحمد، سازمان تحقیقات آموزش
2 استادیار، بخش تحقیقات آب و خاک، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی کهگیلویه و بویراحمد، سازمان تحقیقات آموزش و ترویج کشاورزی،
عنوان مقاله [English]
This research was carried out with the aim of achieving the most suitable planting distance and the amount of nitrogen fertilizer per unit area on four promising rice lines 10, 11, 15, and 16 at Kohgiluyeh and Boyerahmad province, Choram city station in 2016 and 2017. The factor of planting distance in three levels of 15x15, 20x20, and 25x25 cm, and the amount of nitrogen in three levels of 50, 100, and 150 kg of N per hectare were factorially considered in the form of a randomized complete block design with three replications. Traits were containing plant height, days to flowering, days to maturity, harvest index, grain yield, and yield components. The result of the analysis showed there is a significant differences between genotypes at a 1% probability level. ANOVA revealed significant differences for different transplant spacing and different rates of nitrogen fertilizer on comparison of grain yield and thousands grain yield. Effects of transplant spacing, and rate of N level so interaction between N level and on grain yield showed significance at 5% probability level. The effect of genotype and transplant spacing were non-significant on days to flowering, days to maturity, while the effect rate of N level significant on other traits at the 5% probability level. The number of seeds per square meter and the number of fertile tillers were the effective components on the difference in grain yield. In whole genotypes had significant difference at most case second transplant spacing with other transplant spacinges. The maximum grain yield was related to genotype No 3 in G3 ×D2× N2 with average of 9.503 Ton ha-1. Therefore, this treatment can be used taking into account economic and environmental considerations.
Rice is one of the most important food products, it supplies the most calories consumed by the people of the world and is produced and consumed in a wide range of climatic conditions. Rice is of special importance in Iran; So that it accounts for the majority of people's food. The increase in population and the ever-increasing human need for food on the one hand and the limitation of production resources on the other hand indicate that one of the ways to achieve more production is to increase the yield per unit area, which can be achieved by producing high-yielding varieties of rice along with the application of suitable agricultural methods. including the density of planting and the amount of suitable nitrogen fertilizer is possible. To achieve optimal yield in rice cultivars, is necessary correct crop management, such as observing planting distance and appropriate use of nitrogen fertilizer.
This experiment was conducted in 2015 and 2016 crop years in Kohgiluyeh and Boyar Ahmad provinces at Cheram city rice station to determine the most suitable planting distance and nitrogen content on four promising lines of rice using a factorial experiment in the form of a randomized complete block design in three replications. became. The factors included rice lines in four levels, planting distance in three levels 25 x 25, 20 x 20 and 15 x 15 cm and the amount of nitrogen in three levels were 50, 100 and 150 kg of pure nitrogen per hectare. The tested lines included lines 10, 11, 15 and 16. The required nitrogen based on 70% of the basic fertilizer from the source of ammonium nitrate was used before the last plowing along with triple superphosphate at the rate of 150 kg per hectare. Potash was calculated in the amount of 100 kg/ha from the source of potassium sulfate and sprinkled on the main land. 30% of nitrogen was sprayed in the field at the stage of initial cluster formation in the stem about 35 days after transplanting. Seeding was done in the first half of May after seed disinfection in the prepared treasury beds. Nasha was transferred to the main field after losing 4-3 in the second half of June. Transplanting was done with 25x25, 20x20 and 15x15 cm intervals in 3x4 meters plots. The investigated traits included the number of days to flowering, the number of days to maturity, plant height, harvest index, yield components and seed yield.
The results showed that there is a significant difference between the genotypes in terms of grain yield at the level of one percent probability. The effect of planting intervals, nitrogen fertilizer levels, as well as the mutual effect of planting intervals and nitrogen fertilizer levels on seed performance was statistically significant at the 5% probability level. The effect of genotypes and planting intervals on plant height, number of days to flowering, and number of days to maturity were not significant; While the effect of nitrogen fertilizer on other traits was significant at the 5% probability level. The increase of nitrogen fertilizer and the decrease of planting distance significantly decreased the grain yield. The number of seeds per square meter and the number of fertile tillers were the effective components on the difference in grain yield. The results showed that the seed yield of the genotypes in the second transplanting interval had a significant difference with other transplanting intervals. The highest seed yield of genotype 3 treatment was obtained at the second transplanting distance (20 x 20 cm) and the second level of nitrogen fertilizer consumption (100 kg/ha) amounting to 9.503 tons/ha. In this experiment, no statistically significant difference was observed between the consumption of 100 and 150 kg per hectare of pure nitrogen fertilizer.
The most important components affecting yield are the number of seeds per square meter and the number of fertile tillers per plant. Due to the high solubility of nitrogen fertilizer and the effect of chemical pollution on the environment; Therefore, in order to preserve the environment and yield stability, it is appropriate to use 100 kg per hectare of pure nitrogen fertilizer and plant density of 20 x 20 cm. In addition, are significantly improved with the optimal use of nitrogen fertilizer, the economic benefits of rice farmers.