The comparative evaluation of fourteen types of ramie under Cuban conditions

Investigations were conducted at the Cuban Agricultural Experiment Station to determine the comparative growth response and production of fiber of Boehmeria utilis and B. japonica and of 12 types of B. nivea, all of which had been accumulated from various parts of the world. Following the customary commercial practice, three crops were harvested during the growing season. The maximum yield of stems and leaves for the three harvests, under the experimental conditions described, was 41,367 pounds per acre which was produced by type de Francia. The three highest producers of defoliated stems were types de Francia, C, and A, each producing 22,411, 20,328, and 18,999 pounds per acre, respectively. Type C was the leading fiber producer with a production of 565 pounds of dry, degummed fiber per acre. Types de Francia and D were second and third in this respect with a production of 517 and 505 pounds per acre. Types antigua de botanica, Florida, and 15752 were consistently the least productive of the group. By comparison with yields reported in other countries where this plant is grown commercially, the yields obtained from some of the types used in the investigation reported here may be considered excellent. Americana was the most prolific stem producer but at the same time was the shortest growing type. It would seem advisable, through a breeding and selection program, to combine the prolific growth habits of Americana with the more vigorous and high fiber producing capacity of types D, C, or de Francia. As harvests were made successively later in the growing season, the percentage of short, unusable material of the total yield progressively increased as a result of soil moisture deficiency. After the first year of production, however, it is believed that, under Cuban conditions, crops of about equal production might be harvested the end of June, August, and October. Harvesting on these dates would allow each crop to grow for approximately 60 days during the rainy season. Fiber from type Americana was judged to be the finest in texture, followed in order by fiber of de Francia and C, while the fiber produced by type usitatissima was the most coarse in texture. The average percentage of fiber of the green weight of defoliated stems for the 14 types was 2.2. In this respect, type D was outstanding in that it produced an average of 2.8% fiber of the green weight of its stems. The average percentage of fiber of the green weight of ribbons for all types was 8.4. Comparative data are presented on the composition of stems 60 days or less in age and stems 60 to 120 days in age which show that the relative percentages of fiber and ribbons are practically identical in the different aged stems. These data would suggest, as far as percentage of fiber is concerned, that harvesting should be done as soon as the ultimate height of the crop is reached. Based on the experimental data and information obtained, types C, de Francia, and D appear to be better adapted for production under Cuban conditions, at least from the standpoint of yield of fiber, than the remainder of the 14 types tested.