Impact of planting dates on incident and absorbed photosynthetically active radiation of potato crop under different irrigation frequencies

Abstract

A farm level experiment was carried out with two (i.e. Jyoti and Ashoka) different potato cultivars (i.e. Ashoka and Jyoti) at “C” block farm of the Bidhan Chandra Krishi Viswavidyalaya during November-March (2009-2010) to assess the incident (IPAR) and absorbed (APAR) photosynthetically active radiation of potato under three different irrigation levels (I1, I2 and I3) with 3 cm irrigation depth. The experiment was conducted under two planting dates (D1: 20/11/2009 and D2: 29/11/2009) during the above period. The plot size was 4.5 m × 3.7 m. The soil was sandy-loam with medium land situation. In a particular day, readings were taken four times with two hours interval (9:00, 11:00, 13:00 and 15:00 h). Throughout the period, it was observed that the maximum IPAR and APAR values were at 11:00 h irrespective of the irrigation frequency, planting date and variety of potato.