The aim of this study was to determine the pungency level of different accessions of Habanero peppers. The high-performance liquid chromatography (HPLC) technique was used to evaluate the content of total capsaicinoids in the whole fruit, placenta, and pericarp of 18 accessions of Habanero pepper from the germplasm bank of the Capsicum chinense species maintained in the Scientific Research Center of Yucatan [Centro de Investigación Científica de Yucatán (CICY)]. Thirteen of these accessions belonged to the “orange type”, four to the “red type”, and one to the “yellow type”. During the study, the plants were cultivated and maintained under greenhouse conditions and the fruit was harvested only when it was completely ripe on the plant. The results show considerable intraspecific diversity for this characteristic as well as the existence of cultivars of this species that surpass the levels of pungency reported for Habanero peppers under the conditions evaluated.

A complete and efficient regeneration protocol was developed for Vanilla planifolia ‘Andrews’, an endangered orchid species that represents an important crop in several tropical countries. Axillary buds excised from the first to the eighth node, considering the first to fourth nodes as “young” (zone 1) and the fifth to eighth as “mature” (zone 2), were cultured on Murashige and Skoog (MS) medium supplemented with 5.73, 7.64, 9.55, or 11.46 μ m 6-benzylaminopurine (BA) for shoot induction and in combination with 4.45 μ m naphthalene acetic acid (NAA) to induce multiple shoot proliferation. Cytokinin concentration and bud position in the stem had a significant effect on the number of shoots regenerated. The greatest shoot formation per explant, for the two tested zones, was obtained with 9.55 μ m BA on MS medium supplemented with 100 mg·L ⁻¹ myoinositol, 150 mg·L ⁻¹ citric acid, 100 mg·L ⁻¹ ascorbic acid, and 20 g·L ⁻¹ sucrose. Young buds from zone 1 were able to form an average of 18.5 ± 2.4 shoots per explant, whereas buds from zone 2 induced a maximum of 11.0 ± 1.0 shoots per explant. Plants of 2 to 3 cm height developed a root system in half-strength MS medium supplemented with 0.44 μ m NAA and, once they reached 5 cm height on average, were transferred to greenhouse conditions for their acclimatization where a 100% rate survival was achieved. The optimal use of both young and mature buds from each mother plant to induce adventitious shoots permitted a marked increase in the number of shoots per explant. By using all buds from the upper stem part (zone 1 + zone 2) and subculturing every 90 d, the multiplication rate was 1.1 to 1.86 × 10 ⁵ shoots per bud per year.

The Yucatan Peninsula is recognized as the center of genetic diversity of Habanero peppers ( Capsicum chinense Jacq.), which can be distinguished from those cultivated in other regions of the world by their aroma, taste, and—most of all—by their pungency. We evaluated three commercial varieties of chili peppers reported as being the hottest in the world: ‘Bhut Jolokia’, ‘Trinidad Moruga Scorpion’, and ‘Carolina Reaper’. The aim of our study was to determine the behavior of the pungency when cultivated under the edaphoclimatic conditions of Yucatan. Our results show that the three varieties registered greater contents in comparison with those reported in other regions of the world. ‘Carolina Reaper’—considered to be the hottest variety in the world, with a pungency of 2,200,000 Scoville heat units (SHU)—when cultivated in Yucatan, had a pungency of 3,006,330 SHU, which was greater than all the other varieties analyzed.

This article describes the performance of nodal segments from Habanero pepper ( Capsicum. chinense ) during shoot induction and elongation under different semisolid and liquid culture conditions with various degrees of ventilation in which they were exposed to different levels of immersion and growth regulators. The ethylene content in non-ventilated containers, the age of the explant donor plants as well as the effect of thidiazuron and paclobutrazol on shoot induction and of gibberellic acid and AgNO ₃ on shoot elongation were also evaluated. A temporary immersion bioreactor (BioMINT™) was used for the multiplication and elongation of isolated shoots with very good results. We report an efficient protocol for the in vitro propagation of Habanero pepper that produces plants with a high survival rate when transplanted to soil.

Intersimple sequence repeat (ISSR) markers were used to evaluate the effects of in vitro culture on genetic variation in Habanero pepper ( Capsicum chinense Jacq.) regeneration protocols. A total of 219 ISSR clear and reproducible fragments were generated with 13 ISSR primers in direct organogenesis, direct and indirect somatic embryos, and the embryogenic callus system. A cluster analysis was performed to express in the form of dendrogram the relationships among different regeneration systems and the genetic variability detected. Genetic distance analysis indicated that our regeneration protocols are inappropriate for micropropagation, conservation, or genetic transformation; however, they may be applicable to breeding. This is the first report on the use of molecular analysis to evaluate genetic variation of in vitro-regenerated plants of Habanero pepper using ISSR markers.