Transplanting shock in temperate rice and its influence on rooting characteristics and grain yield

In temperate Kashmir, generally low temperature during night prolong the nursery age up to 50 days to attain transplantable seedlings. Older seedlings may suffer more due to transplanting shock, reducing tillering capacity. A pot experiment was conducted under field conditions to study the transplanting shock in temperate rice and its influence on rooting characteristics and grain yield in Kashmir Valley. Four seedlings age (0, 20, 35 and 50 days old) were evaluated by CRD during 2008. The delay in heading due to transplanting (transplanting shock), defined as the difference in the days from emergence to heading between transplanted and direct seeded rice, ranged from 5 to 14 days. Direct seeded (0 days), 20 and 35 days old seedlings recorded grain yield increase over 50 days seedlings by 28.3, 18.5 and 9.8% respectively. Root length, root dry weight and root volume showed significant decreasing trend with increased seedling age at heading. Regression equation revealed that grain yield was highly associated with rooting characteristics.