Physiological responses of sweet corn under water deficit and nitrogen rates at different growth stages

Subject Areas : Journal of Plant Ecophysiology

A.  Shahriari ¹ (استادیار مرکز تحقیقات کشاورزی و منابع طبیعی هرمزگان)
A.B.  Puteh ² (دانشیار دانشکده کشاورزی دانشگاه UPM مالزی)
A.B.  Abdul Rahim ³ (دانشیار دانشکده کشاورزی دانشگاه UPM مالزی)
G.B.  Saleh ⁴ ()

Received: 2015-01-26 Accepted : 2015-01-26 Published : 2015-01-01

Keywords: Nitrogen deficit, photosynthesis rate, Proline content, Relative water content, stomata conductance, water stress,

Abstract :

Water deficit is one of the main factors limiting production in arid and semiarid regions. This study was carried out to investigate the effect of the interaction of water deficit  and N fertilizer rate on relative water content, proline content, leaf chlorophyll content,  pollen number  and pollen viability, photosynthesis rate and stomata conductance parameters in two hybrid sweet corn ( 968 and 926) in greenhouse condition. The experimental layout was split plot factorial design arranged in a randomized complete block design with three replications in 2010 in the Agriculture Crop Science, Putra University Malaysia (UPM). Treatments consisted of four levels of irrigation (including irrigating all the growing season (control), vegetative drought, reproductive drought and vegetative and reproductive drought), three levels of Nitrogen as urea (40, 120 and 200 kg ha-1) and two varieties of sweet corn varieties (including hybrids 968 and 926), respectively. Results showed that the interaction effects of water deficit and Nitrogen fertilizer were significant and reduced leaf chlorophyll content, photosynthetic rate and stomata conductivity under water and Nitrogen rate deficit. Also the results showed that water deficit at vegetative and productive growth stages reduced photosynthesis rate compared to normal irrigation by 54% and 84%, respectively.  But Nitrogen treatments at 200 and 120 kg ha-1 did not show any significant decrease in stomata conductivity. Whereas. Proline content increased under water deficit. Pollen number reduced with water and nitrogen deficit. Pollen viability reduced only under water deficit by 39%.