واكنش رشد و عملكرد برنج به تاريخ بذرپاشي و روش كاشت در كشت مستقيم در رشت

Response of rice growth and grain yield to seeding date and planting method in direct seeding in Rasht

ﺗﻐﯿﯿﺮ ﻧﻈﺎم ﮐﺸﺖ ﺑﺮﻧﺞ از ﮐﺸﺖ ﻧﺸﺎﯾﯽ ﺑﻪ ﮐﺸﺖ ﻣﺴﺘﻘﯿﻢ، ﺳﺒﺐ ﮐﺎﻫﺶ ﻗﺎﺑﻞ ﺗﻮﺟﻪ ﻧﯿﺮوي ﮐﺎرﮔﺮي و ﻫﺰﯾﻨﻪﻫﺎي ﺗﻮﻟﯿﺪ ﻣﯽﺷﻮد. ﺑﻪﻣﻨﻈﻮر ﺑﺮر ﺳﯽ اﺛﺮ ﺗﺎرﯾﺦ ﺑﺬرﭘﺎ ﺷﯽ و روش ﮐﺎ ﺷﺖ ﺑﺮ ر ﺷﺪ و ﻋﻤﻠﮑﺮد رﻗﻢ ﻫﺎ ﺷﻤﯽ در ﮐ ﺸﺖ ﻣ ﺴﺘﻘﯿﻢ، آزﻣﺎﯾ ﺸﯽ در ﺳﺎل 1397 ﺑﻪﺻﻮرت ﮐﺮتﻫﺎي ﺧﺮد ﺷﺪه و در ﻗﺎﻟﺐ ﻃﺮح ﭘﺎﯾﻪ ﺑﻠﻮكﻫﺎي ﮐﺎﻣﻞ ﺗﺼﺎدﻓﯽ در ﻣﺆﺳﺴﻪ ﺗﺤﻘﯿﻘﺎت ﺑﺮﻧﺞ ﮐﺸﻮر-رﺷﺖ اﻧﺠﺎم ﺷﺪ. ﻋﺎﻣﻞ اﺻﻠﯽ ﺷﺎﻣﻞ ﺗﺎرﯾﺦ ﺑﺬرﭘﺎﺷﯽ )18 ،11 و 25 اردﯾﺒﻬﺸﺖ و ﯾﮏ، ﻫﺸﺖ، 15 و 22 ﺧﺮداد( و ﻋﺎﻣﻞ ﻓﺮﻋﯽ ﺷﺎﻣﻞ روش ﮐﺎ ﺷﺖ )د ﺳﺖﭘﺎش، ﮐﺎ ﺷﺖ ﺧﻄﯽ و ﮐﺎ ﺷﺖ ﮐﭙﻪاي( ﺑﻮدﻧﺪ. ﻫﻤﭽﻨﯿﻦ، ﺗﯿﻤﺎر ﺷﺎﻫﺪ ﮐ ﺸﺖ ﻧ ﺸﺎﯾﯽ ﻧﯿﺰ ﺑﻪ ﺗﯿﻤﺎرﻫﺎي آزﻣﺎﯾﺸﯽ اﻓﺰوده ﺷﺪ. ﺗﺠﺰﯾﻪ وارﯾﺎﻧﺲ ﻧﺸﺎن داد ﮐﻪ اﺛﺮ ﺗﺎرﯾﺦ ﺑﺬرﭘﺎﺷﯽ ﺑﺮ ﻋﻤﻠﮑﺮد ﺷﻠﺘﻮك ﻣﻌﻨﯽدار ﺑﻮد، وﻟﯽ اﺛﺮ روش ﮐﺎﺷﺖ و اﺛﺮ ﻣﺘﻘﺎﺑﻞ ﺑﯿﻦ آنﻫﺎ ﺑﺮ ﻋﻤﻠﮑﺮد ﺷﻠﺘﻮك ﻣﻌﻨﯽدار ﻧﺒﻮد. ﺣﺪاﮐﺜﺮ ﻋﻤﻠﮑﺮد ﺷﻠﺘﻮك ﺑﻪﻣﯿﺰان 4414 و 4325 ﮐﯿﻠﻮﮔﺮم در ﻫﮑﺘﺎر، ﺑﻪﺗﺮﺗﯿﺐ در ﺗﺎرﯾﺦ ﺑﺬرﭘﺎﺷﯽ 11 و 25 اردﯾﺒﻬﺸﺖ ﺑﻪدﺳﺖ آﻣﺪ و ﺗﺄﺧﯿﺮ در ﺑﺬرﭘﺎﺷﯽ، ﻣﻨﺠﺮ ﺑﻪ ﮐﺎﻫﺶ ﻣﻌﻨﯽدار ﻋﻤﻠﮑﺮد ﺷﺪ، ﺑﻪ ﻃﻮريﮐﻪ ﻋﻤﻠﮑﺮد ﺷﻠﺘﻮك در ﺗﺎرﯾﺦ ﺑﺬرﭘﺎﺷﯽ ﯾﮏ، ﻫﺸﺖ و 15 ﺧﺮداد در ﻣﻘﺎﯾﺴﻪ ﺑﺎ ﺗﺎرﯾﺦ ﺑﺬرﭘﺎﺷﯽ 11 اردﯾﺒﻬﺸﺖ، ﺑﻪﺗﺮﺗﯿﺐ 43 ،41 و 70 درﺻﺪ ﮐﺎﻫﺶ ﯾﺎﻓﺖ. ﻫﻤﭽﻨﯿﻦ ﺑﯿﻦ ﻋﻤﻠﮑﺮد ﺷﻠﺘﻮك در ﮐﺸﺖ ﻣﺴﺘﻘﯿﻢ )4414±184 ﮐﯿﻠﻮﮔﺮم در ﻫﮑﺘﺎر( و ﮐﺸﺖ ﻧﺸﺎﯾﯽ )4295±215 ﮐﯿﻠﻮﮔﺮم در ﻫﮑﺘﺎر( اﺧﺘﻼف ﻣﻌﻨﯽداري وﺟﻮد ﻧﺪاﺷﺖ. در ﺿﻤﻦ، وزن ﺧﺸﮏ ﻋﻠﻒﻫﺎيﻫﺮز ﺗﺤﺖ ﺗﺄﺛﯿﺮ ﺗﺎرﯾﺦ ﺑﺬرﭘﺎﺷــﯽ و روش ﮐﺎﺷــﺖ ﻗﺮار ﻧﮕﺮﻓﺖ. ﺑﻪﻃﻮرﮐﻠﯽ و ﺑﺮاﺳــﺎس ﻧﺘﺎﯾﺞ اﯾﻦ ﺗﺤﻘﯿﻖ، ﻋﻤﻠﮑﺮد ﻣﻄﻠﻮب ﺑﺮﻧﺞ در ﮐﺸــﺖ ﻣﺴﺘﻘﯿﻢ، ﺑﺎ ﺑﺬرﭘﺎﺷﯽ از ﺗﺎرﯾﺦ 11 ﺗﺎ 25 اردﯾﺒﻬﺸﺖ ﺑﻪدﺳﺖ آﻣﺪ.

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.