Flue‐cured Tobaccos With Varied Ripening Pattern for Modified Harvest Systems 1

Mechanically harvesting flue‐cured tobacco ( Nicotiana tabacum L.) requires uniform ripening of leaves. Tobaccos are available with varied ripening patterns and a test was conducted to determine which may be more adaptive to varied harvesting systems. Flue‐cured cultivars ‘Coker 139’ and ‘NC 95’ and a pale yellow hybrid were used. These tobaccos varied in ripening patterns, total alkaloids, and reducing sugars. Harvest systems used were conventional, twice‐over, and once‐over for 61 cm and 115 to 140 cm (normal) topping heights. The time of topping was varied in the once‐over harvest systems. All of the modified systems, except when the pale‐yellow hybrid was harvested twice, resulted in reduced yield compared to that of the conventional system. Yields were progressively reduced by the low‐topped treatments as the time of topping was delayed. Plants which were topped normally and had all of the leaves removed at one time produced the most undesirable tobacco; with NC 95 and the pale‐yellow hybrid being the poorest. Total alkaloids were higher in tobacco from the low‐topped, once‐over harvest treatment (except that topped at harvest) than in that produced from the conventionally topped and harvested treatment. However, with a low‐alkaloid cultivar (Coker 139), an acceptable level of total alkaloids was obtained in the low‐topped, once‐over harvested tobacco when the plants were topped early. Cured leaf was produced from some of the low‐topped once‐over harvested treatments, that equalled that produced by conventionally topped and harvested for value per 45.4 kg, total alkaloids, and reducing sugars.