Univrsity of Tehran Press Iranian Journal of Field Crop Science 2008-4811 52 1 2021 03 21 Response of rice growth and grain yield to seeding date and planting method in direct seeding in Rasht Response of rice growth and grain yield to seeding date and planting method in direct seeding in Rasht 143 154 80955 10.22059/ijfcs.2020.292288.654656 FA Akbar Latifi Department of Agronomy and Plant Breeding, Rasht Branch, Islamic Azad University, Rasht, Iran. Hashem Aminpanah Department of Agronomy and Plant Breeding, Rasht Branch, Islamic Azad University, Rasht, Iran. Bijan Yaghoubi Rice Research Institute of Iran (RRII), Agricultural Research, Education and Extension Organization (AREEO), Rasht, Iran. Journal Article 2019 11 11 Changing rice cultivation system from puddle transplanting to direct seeding greatly reduces labor and crop production costs. A field experiment was conducted at Rice Research Institute of Iran-Rasht in 2018 as split plot based on a randomized complete block design to evaluate the effect of seeding date and planting method on growth and grain yield of Hashemi cultivar in direct seeding method. Main plots included seeding date (May 1, 8, 15, 22, 29 and June5 and 12) and sub plots were planting methods (broadcast seeding, row seeding and hill seeding). Moreover, transplanting plots were included to the experiment as control treatment. Analysis of variance showed that seeding date had significant effects on paddy yield but planting method and their interaction had no significant effect on paddy yield. Maximum paddy yield were recorded at the dates of 1 and 15 May (4414 and 4325 kg ha^-1, respectively). Paddy yield was significantly reduced when seeding date delayed, as grain yield reduce by 41%, 43%, and 70% at the seeding dates of 22 and 29 May, and 5 June compared to the seeding date of 1 May. There was no significant difference in paddy yield between direct seeding (4295±215 kg ha^-1) and transplanting (4414±184 kg ha^-1) production systems. Moreover, seeding date and planting method had no significant effect on weed biomass. In general, result revealed that optimum paddy yield in direct seeding was recorded at the seeding date of 1 and15 May. Changing rice cultivation system from puddle transplanting to direct seeding greatly reduces labor and crop production costs. A field experiment was conducted at Rice Research Institute of Iran-Rasht in 2018 as split plot based on a randomized complete block design to evaluate the effect of seeding date and planting method on growth and grain yield of Hashemi cultivar in direct seeding method. Main plots included seeding date (May 1, 8, 15, 22, 29 and June5 and 12) and sub plots were planting methods (broadcast seeding, row seeding and hill seeding). Moreover, transplanting plots were included to the experiment as control treatment. Analysis of variance showed that seeding date had significant effects on paddy yield but planting method and their interaction had no significant effect on paddy yield. Maximum paddy yield were recorded at the dates of 1 and 15 May (4414 and 4325 kg ha^-1, respectively). Paddy yield was significantly reduced when seeding date delayed, as grain yield reduce by 41%, 43%, and 70% at the seeding dates of 22 and 29 May, and 5 June compared to the seeding date of 1 May. There was no significant difference in paddy yield between direct seeding (4295±215 kg ha^-1) and transplanting (4414±184 kg ha^-1) production systems. Moreover, seeding date and planting method had no significant effect on weed biomass. In general, result revealed that optimum paddy yield in direct seeding was recorded at the seeding date of 1 and15 May. https://ijfcs.ut.ac.ir/article_80955_45f8e17a879d17c4d8f3b1414ecdf783.pdf