Yield, yield components and physico-chemical characters of the ratoon crop of Iranian rice cultivars

Abstract

The ratooning ability of five Iranian rice cultivars and the grain quality of the ratoon crop were evaluated in a randomized complete block design with four replications in consecutive years from 1999 to 2001 to select promising lines for economical ratoon culture. The main crop was harvested by cutting 30 cm above the soil surface for regrowth of the second (ratoon) crop. The ratoon grain yields (kg/ha) varied greatly among the cultivars, ranging from 144.9 (Haseni) to 1472.1 (Sang-e-Tarom). In general, the ratoon crops had fewer fertile spikelets, fewer spikelets per panicle, shorter panicle length and fewer primary and secondary branches per panicle than the main crop. The gelatinization temperature and gel consistency of rice grains from ratoon crops were lower than those of the main crops. The amylose content (%) of the grains from ratoon crops varied from 23.1 (Sang-e-Tarom) to 21.4 (Dailamani).