Rice is the most important crop at the global level, as it used as a staple food in the most countries of the
world. Achieving a sustainable increase in rice production can improve global food security and contribute
to poverty alleviation. Selection of suitable planting density and seedling age are the most important factors
for maximizing rice production. In order to study the effects of seedling age and planting spaces on yield
and yield components of rice (Neda variety) a fi eld experiment was carried out in fi eld of Ghaemshahr
Azad University. Experimental design was arranged in split plot in basis of Randomized Completely Block
Design with four replication. Some agronomical traits such as total tiller number, fertile tiller number,
panicle number per m2
, total spikelet per panicle, total strile spikelet per panicle, 1000 grains weight and
grain yield were measured. Results showed that the effect of seedling age on total tiller number and panicle
number per m2 was signifi cant at 0.01 probability level. Also seedling age had a signifi cant effect on fertile
tiller number at 0.05 probability levels. Planting spaces had a signifi cant effect on total tiller, fertile tiller,
panicle per m2
, total spikelet per panicle and grain yield. When the age of seedling is less than optimum, the
tender seedlings may die in greater number due to high temperature and ultimately the plant population is
reduced.For this variety transplanting in seedling age at 25 day and 15 cm×15 cm planting space for the
best performance of yield attributes were recommended