Response of Virginia tobacco (Nicotiana tabacum Linn.) grown after lowland rice to tillage system and time of planting

Based on the result of the study, early planting of tobacco produced the tallest plant, biggest stem diameter, widest leaf area and the earliest to bear flowers although plants did not differ significantly in terms of these parameters when compared to medium planting. Time of planting tobacco also affected the leaf area index (LAI) and relative leaf growth rate (RLGR) of tobacco. Leaf area index was higher in regular time of planting of tobacco at 60 DAT while the RLGR was also higher in regular time of planting at 45-60 DAT. No significant differences on the LAI and RLGR of tobacco were observed at later growth stages. Similarly, the crop growth rate (CGR) of tobacco was not affected by time of planting at any growth stages. Leaf size was longer and wider in tobacco plants grown at early and regular planting dates in the cutter and tip leaf stalk positions but not in the lug leaves. The smaller leaves produced from late planting was accompanied by an increase in specific leaf weight (SLW) and leaf thickness in all leaf stalk positions. Breadth index of tobacco was not significantly affected by time of planting in any of the leaf stalk position. Moreover, the total reducing sugar and nicotine content of flue-cured tobacco leaves were highest from early and medium planting dates in all leaf stalks positions. The yield of tobacco obtained from early and medium planting dates were significantly higher compared with the late planting. Similarly, tobacco plants taken from plots with conventional and minimum tillage with or without mulch were taller, had bigger stem diameter, wider leaf area and produced flowers early as compared to those tobacco plants with strip or zero tillage treatments. In general, the physical leaf qualities of virginia tobacco were very much affected by the tillage method used. Leaf size was longer and wider from conventional and minimum tillage plots with or without mulch. The specific leaf weight (SLW) of tobacco was higher in zero tilled plots with or without mulch in the lug leaf stalk position but not in the cutter and tip leaves. A similar result was also noted on the leaf thickness in the lug and cutter leaves