Different Seed Selection and Conservation Practices for Fresh Market and Dried Chile Farmers in Aguascalientes, Mexico

Biocultural diversity and crop improvement

Biocultural diversity is the ever-evolving and irreplaceable sum total of all living organisms inhabiting the Earth. It plays a significant role in sustainable productivity and ecosystem services that benefit humanity and is closely allied with human cultural diversity. Despite its essentiality, biodiversity is seriously threatened by the insatiable and inequitable human exploitation of the Earth's resources. One of the benefits of biodiversity is its utilization in crop improvement, including cropping improvement (agronomic cultivation practices) and genetic improvement (plant breeding). Crop improvement has tended to decrease agricultural biodiversity since the origins of agriculture, but awareness of this situation can reverse this negative trend. Cropping improvement can strive to use more diverse cultivars and a broader complement of crops on farms and in landscapes. It can also focus on underutilized crops, including legumes. Genetic improvement can access a broader range of biodiversity sources and, with the assistance of modern breeding tools like genomics, can facilitate the introduction of additional characteristics that improve yield, mitigate environmental stresses, and restore, at least partially, lost crop biodiversity. The current legal framework covering biodiversity includes national intellectual property and international treaty instruments, which have tended to limit access and innovation to biodiversity. A global system of access and benefit sharing, encompassing digital sequence information, would benefit humanity but remains an elusive goal. The Kunming-Montréal Global Biodiversity Framework sets forth an ambitious set of targets and goals to be accomplished by 2030 and 2050, respectively, to protect and restore biocultural diversity, including agrobiodiversity.

Aeroponic Cloning of Capsicum spp

Aeroponic cloning is a great strategy to maintain desired genotypes by generating a whole new plant from cuttings. While this propagation technique has been demonstrated for tomatoes (Solanum lycopersicum) and potatoes (Solanum tuberosum), no protocol has been developed for peppers (Capsicum spp.). The ability to clonally propagate different Capsicum holds promise for domestic and industrial growing operations since elite cultivars with desirable traits (e.g., high capsaicin levels, nutrient content, and striped fruit) can be perpetuated without the need of planning a nursery. We tested six Capsicum species for their feasibility of aeroponic cloning by stem cuttings. All domestic species were successfully regenerated under aeroponic conditions but not for Capsicum eximium, a wild species. Of the species analyzed, Capsicum annuum peppers had the fastest node formation (11.6 +/− 0.89 days, P ≤ 0.01) and obtained a larger volume of roots (P ≤ 0.01) after node formation as compared to C. baccatum, C. frutescens, and C. pubescens. This study presents a cost-effective strategy to clonally propagate peppers for personal, industrial, and conservation purposes.

Multiple lines of evidence for the origin of domesticated chili pepper, Capsicum annuum, in Mexico

The study of crop origins has traditionally involved identifying geographic areas of high morphological diversity, sampling populations of wild progenitor species, and the archaeological retrieval of macroremains. Recent investigations have added identification of plant microremains (phytoliths, pollen, and starch grains), biochemical and molecular genetic approaches, and dating through (14)C accelerator mass spectrometry. We investigate the origin of domesticated chili pepper, Capsicum annuum, by combining two approaches, species distribution modeling and paleobiolinguistics, with microsatellite genetic data and archaeobotanical data. The combination of these four lines of evidence yields consensus models indicating that domestication of C. annuum could have occurred in one or both of two areas of Mexico: northeastern Mexico and central-east Mexico. Genetic evidence shows more support for the more northern location, but jointly all four lines of evidence support central-east Mexico, where preceramic macroremains of chili pepper have been recovered in the Valley of Tehuacán. Located just to the east of this valley is the center of phylogenetic diversity of Proto-Otomanguean, a language spoken in mid-Holocene times and the oldest protolanguage for which a word for chili pepper reconstructs based on historical linguistics. For many crops, especially those that do not have a strong archaeobotanical record or phylogeographic pattern, it is difficult to precisely identify the time and place of their origin. Our results for chili pepper show that expressing all data in similar distance terms allows for combining contrasting lines of evidence and locating the region(s) where cultivation and domestication of a crop began.