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however, depended on sowing time and the duration of the varieties used. Almost allfarms in the region experienced drought at the intermediate stage.Farmers in this region normally do final land preparation and sow rice in the3rd week of June after the onset of effective monsoon. This results in an avoidableloss of initial monsoon moisture to some extent and in delayed sowing in years ofcontinuous rains because of poor workability of the soil. In such cases, crops aremore likely to suffer from drought at the terminal stages of growth. Advance sowingbefore the onset of monsoon was therefore considered as one of the strategies foravoiding or minimizing the effects of terminal drought, which is of longer durationand has a higher probability of occurrence (Table 1). The other strategy in this respectwas to use the selected rice cultivars of short maturity duration (90–100 d) that hadshown consistently better performance in previous on-station and on-farm experiments.The results of advance sowing, done on around 7 June before the onset ofrains, indicated significantly higher grain yield, number of panicles m –2 , number offertile spikelets panicle –1 , and taller plants in all the genotypes tested than sowingdone around 22 June after the onset of rain (normal practice) (Table 2). Among thegenotypes, Brown Gora and Kalinga III were inferior to RR167-982 (Vandana) andRR165-1160 in all respects including panicle weight and panicle length (Table 2).The early sown plots, however, had a higher weed infestation at the early stagesof plant growth owing to the simultaneous emergence of weeds with rice upon thefirst rain showers. In normal sown plots, the weeds had germinated before rice seedingand were destroyed with the additional harrowing. Therefore, weed managementwas followed along with advance sowing in successive experiments that also includedseeding method and rice plant population studies.With advance sowing, grasses dominated the weed flora in the initial stages ofcrop growth followed by dicotyledons in the latter stages. The bulk of the weed floraconstituted Cyperus rotundus, Cyperus iria, Echinochloa colona, Cynodon dactylon,Setaria glauca, Commelina benghalensis, Aeschynomene indica, and Brachiariaramosa, which competed with rice during all its growth stages. The population ofAgeratum conyzoides was severe at the reproductive stage only. Losses in rice grainyield (difference between a weed-free and weedy plot) were as high as 77%, and werehigher in drilled than broadcast-seeded crops. However, when manually weeded at 20and 40 days after sowing, the drilled crop produced significantly higher yield (2.4 tha –1 ) than the manually weeded broadcast crop (2.0 t ha –1 ). Application of butachlorwith one handweeding was as effective as two handweedings in both systems.The initial 4-wk period of crop growth was crucial for weeding in the case ofearly maturing tall genotypes, such as Kalinga III, having poor early vigor in contrastwith the semitall genotypes, such as RR167-982 (Vandana) and Brown Gora, thathave higher early vigor and a suppressive effect on weeds.Plant population, attained using a seeding rate of 500 seeds m –2 or 112.5 kgha –1 , and closer row spacing (20 cm) also had a suppressive effect on weeds, as reflectedby lower weight of total weed dry matter. Rice grain and straw yields werehigher under these practices than using a higher or lower seeding rate (400 or 600seeds m –2 ) and sowing by broadcast or with wider row spacing (30 cm).198 Borkakati et al