Management of rice production systems to increase productivity

Days to 50% flowering Grain yield
Plant height at harvest Harvest index
Panicle count per m² Time spent on transplanting
Number of grains per panicle Soil nutrient level
Percentage filled grains per panicle Seedling growth rate
1000 grain weight Root re‐growth rate
3.3. Results and Discussions
3.3.1. Diagnosing Seedling Growth Rate and Seedling Quality
The optimum number of days in the nursery bed varies with the
variety, air temperature, water temperature, and seeding rate. The optimum‐
aged seedlings can hardly be expressed by the number of days. Although
Gines et al. (1985) noted that photoperiod sensitive cultivars were relatively
insensitive to difference in age of seedling at transplanting, it must be noted
that during the process of uprooting seedlings, physical damages to the roots
occur and recovery from physical damages and adjustment to a new growth
media after transplanting need to be taken into consideration.
For SRI management practices, seedlings at 2 leaves stage are
recommended for transplanting. The age at which seedlings reach a specific
leaf stage depends on agro‐climatic factors and genotypic growth rate.
Knowledge of the number of days seedlings will need to be ready for
transplanting helps farmers plan their land preparation and transplanting
calendar adequately. It is also important to identify the critical stage a
seedling age has a significant impact on seedling quality. Farmers in The
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