ILLUSTRATED DESCRIPTION OF A TRADITIONAL DEEPWATER RICE VARIETY OF BANGLADESH

This report graphically illustrates observed stages of Chota Bawalia"s growth with special emphasis on nodes, nodal roots, panicles, and ripening. In addition, the report briefly assesses the impact of flooding regimes and weeding practices on the variety"s productivity. Chota Bawalia is grown annually in l.5 - 3.5 meters of water on several thousands of hectares in the southern Dacca district on the lower Januna floodplain of central Bangladesh. Farmers sow it with the first good rains in April and harvest it after floodwater has receded. Flowering, which is strongly induced by photoperiod, begins the first week of October. During the study, Chota Bawalia was harvested between October 29 and November l, l-2 weeks earlier than many other leading varieties. The study revealed that flooding regimes did not seriously submerge Chota Bawalia but did reduce stand density and that rainfall and farmer"s weeding practices strongly influenced Chota Bawalia"s stand density in the preflood period, partly as the result of an attack of the yellow rice borer, Tryporyza incertulas. Mean yields from l9 crop-cuts at Keraniganj over 4 years ranged from l.7 to 3.7 t/ha, less than six other leading deepwater rice varieties studied. Chota Bowalia yields were depressed as the maximum water depth approached 2.3 meters. No chemical fertilizer was applied; fertility was provided by leguminous crops, which are widely grown in the winter off-season and by a large complex of algae associated with the culms and nodal roots. Appended is a 4-item reference list (l980-8l).