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Seed heteromorphism can influence germination and ultimately seedling establishment, particularly in disturbed habitats. This study compared seed and seedling traits across three distinctly colored seed morphs (viz. light-brown, brown, and dark-brown) of the forage legume, Teramnus labialis (L.f.) Spreng. The best quality seeds (i.e., un-parasitized, filled and un-cracked) were brown: 389.3 quality seeds per 1000 units compared with <270/1000 units for the other two morphs. Length, width, volume, and water content were lowest in the light-brown and highest in the dark-brown seeds. Seed thickness and mass were lower in the light-brown seeds. Dark-brown seeds imbibed fastest from 2 h onwards. Germination was comparable across the morphs after 7 days but was lowest in the light-brown (17% at 21 days) and highest in the dark-brown seeds (36% at 21 days) at 14 and 21 days. At 7 days, seedling emergence in the dark-brown seeds (15.0%) was higher than in the other two morphs (4%–6%); this remained so at 14 and 21 days. Seedling growth (number of leaves, stem height and diameter, and root length) was superior in the dark-brown seeds. Seed heteromorphism in T. labialis may allow its persistence in disturbed habitats, and the dark-brown seeds are best suited for seeding in revegetation projects, given their superior germination capacity and seedling vigor. [ABSTRACT FROM AUTHOR]

For the production of dry leaf of Stevia rebaudiana Bertoni under the Cuban climatic conditions, it is necessary to identify the agrotechnical variables with the greatest impact on its yield. Therefore, the objective of this work was to determine the effect of pruning frequency on biomass production and steviolglycoside content. Plants of S. rebaudiana var. Morita II grown for 180 days in the stonecutter were employed. Three pruning frequencies were tested: every 30, 60 and 90 days. As a control, plants without pruning were used. The variables evaluated were the height of the plant, the number of branches per plant, the number of leaves per plant, the fresh and dry mass of the leaves and stems per plant and the percentage of flowering. In addition, the yield of dry mass per hectare was estimated and the content of steviolglycoside was determined. The results revealed that the best pruning frequency of S. rebauidiana plants was every 60 days. The results of the agronomic variables evaluated were higher than those obtained with pruning every 30 and 90 days, with the exception of the height of the plant and the percentage of flowering. With pruning every 60 days the yield was 1.19 t ha-1 and the steviolglycoside content reached 255.39 mg g-1 of dry mass. The results showed that the pruning frequency influences the production of biomass and the main components of the biomass yield, as well as the content of steviolglycosides in clarified aqueous extracts of S. rebaudiana var. Morita II grown under conditions of stonecutter. [ABSTRACT FROM AUTHOR]