Fertilizer Response of Traditional Rice Cultivars with Different Maturity Durations

Abstract

With the aim of understanding the yield and yield components of some traditional rice cultivars which are having different days to maturity, a field experiment was carried out. Fifty traditional rice cultivars were planted in three rows with 15 cm X 20 cm spacing according to randomized complete block design. Each replicate of one cultivar was consisted with 3 rows. Twenty plants of each cultivar were included in to one row and data were recorded in the middle row. The field was plotted using strong bunds for the separation of control experiment and fertilizer applied plots. The plot treated with inorganic fertilizers as Basal Dressing: Urea 50 Kg/ha, TSP 62.5 Kg/ha, MOP 50 Kg/ha and Top Dressing: Urea 37.5 Kg/ha - 2 Weeks after planting and 8 Weeks after planting. Effect of fertilizer on agronomic characteristics namely plant height (cm), number of tillers/plant and number of leaves/plant, grain yield (g/plant) and harvest index were measured before harvesting. Grain yield and the harvest index were calculated at the end of the experiment. Fifty traditional rice cultivars were categorized into eight age groups according to days to maturity; 105-110,111-115,116-120,121-125,126-130,131-135,136-140 and 141-145. Under fertilized conditions plant height was ranged from 119.0 cm -146.4 cm and the highest plant height was observed at the 105-110 early maturing cultivars. The lowest number of tillers (5.7), lowest number of leaves (10.7), lowest yield (10.0 g) and the lowest harvest index (0.28) were recorded by the age group 121-125. In control plants the lowest plant height (103.9 cm), lowest number of tillers (4.7) and the lowest number of leaves (6.7) were recorded by the age group 111-115. Under fertilized conditions the highest number of tillers (8.0) and the highest yield (24.7 g) were recorded by the age group 126-130.The highest number of leaves was recorded by the age group 116-120 both in treatment (18.4) and in controls (10.8). The highest harvest index (0.49) was recorded by the age group 136-140 under fertilized conditions and in non fertilized conditions 0.46 was recorded by the age group 126-130.