Abstract:
Iron toxicity plays a crucial role in determining rice yield, particularly in the
wet zone (WZ) of Sri Lanka. This scenario causes a substantial impact on
above-ground biomass, limits grain yield, and leads to poor root growth of
rice. Therefore, identifying iron toxicity-resistant varieties is essential for
sustaining rice production. The objectives of this research were to determine
the F3 progeny lines derived from four rice crosses. To evaluate the root and
shoot performance of F3 progeny lines derived from four rice crosses under
iron toxicity conditions to identify variations in root morphology and growth
patterns. Four rice crosses and their parents were tested in Randomized
Complete Block Design (RCBD) with 02 blocks. Data were analysis, using
ANOVA and Duncan multiple range test was derived from SAS statistical
software. Cross 2 showed better performance for plant height ( 127.95cm)
and culm height (100.33), flag leaf length (30.71cm) and width (1.1cm) ,
number of tillers ( 8.88/plant), number of effective tillers (7.09/plant),
Number of unproductive tillers ( 0.83), root volume ( 72.73cm3
), root length
(22.90cm), root width (6.55cm), number of roots ( 115.4/plant), root dry
weight (24.76g/plant), panicle length (23.49cm), number (7.09), weight
(7.10g/panicle), seeds (124.92) showed better mean performance. All the
crosses recorded positive heterosis and heterobeltiosis for important yield
related characteristics and morphological characteristics. Among the four
crosses, cross 2 and cross 3 showed better growth and yield performance
when compared with their respective parental lines. Therefore Ld20-14-
12/Ld20-15-14 and Ld20-11-03/Ld21-06-18-12 have the potential to
develop rice lines with better root structure in the future rice breeding
programs.
