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Climate change creates a leverage point in plant breeding. We must rethink the way we employ plant breeding, utilize genetic diversity, and prioritize edible plant production across the landscape. A long-term strategy to ‘redirect’ the process of crop domestication that prioritizes the generation of abiotic and biotic stress-tolerant cultivars is needed. A proposed neo-domestication strategy is presented as a case study. It entails the re-domestication of chile by retro-crossing of modern plant cultivars with landraces and a desert-adapted wild relative. An organized, collaborative effort could reintroduce stress tolerance genes that will render new cultivars more tolerant to challenges imposed by climate change. Purposeful populations generated using a broad spectrum of genetic diversity could also provide the basis for an evolutionary–participatory plant breeding process. The process must recognize the need for a paradigm shift in our resource allocation and breeding strategies. To succeed, a shared vision for neo-domestication of chile must recognize the importance of human cultural values and the need for sustained cooperation among stakeholders.

Fruit shape significantly impacts the quality and commercial value of tomatoes (Solanum lycopersicum L.). Precise grading is essential to elucidate the genetic basis of fruit shape in breeding programs, cultivar descriptions, and variety registration. Despite this, fruit shape classification is still primarily based on subjective visual inspection, leading to time-consuming and labor-intensive processes prone to human error. This study presents a novel approach incorporating machine learning techniques to establish a robust fruit shape classification system. We trained and evaluated seven supervised machine learning algorithms by leveraging a public dataset derived from the Tomato Analyzer tool and considering the current four classification systems as label variables. Subsequently, based on class-specific metrics, we derived a novel classification framework comprising seven discernible shape classes. The results demonstrate the superiority of the Support Vector Machine model in terms of its accuracy, surpassing human classifiers across all classification systems. The new classification system achieved the highest accuracy, averaging 88%, and maintained a similar performance when validated with an independent dataset. Positioned as a common standard, this system contributes to standardizing tomato fruit shape classification, enhancing accuracy, and promoting consensus among researchers. Its implementation will serve as a valuable tool for overcoming bias in visual classification, thereby fostering a deeper understanding of consumer preferences and facilitating genetic studies on fruit shape morphometry.

To maintain the continuous genetic variation and increase the genetic gain, appreciable germplasm diversity and its comprehensive characterization is necessary to further utilize gene sources for pre-breeding. The diversity of pepper forms, cultivation traditions and diverse fruit usages are typical for Balkan countries. Considering this rich diversity, 21 pepper accessions from the Balkan region were evaluated for morphological, biochemical, and insect resistance traits during 2018 and 2019 at Maritsa Vegetable Crops Research Institute, Plovdiv, Bulgaria. Among the studied accessions, the highest productivity was observed in pumpkin shape K1115 and kapia type K1081 accessions, with 0.74 kg and 0.70 kg per plant, respectively. Concerning fruit quality, the highest total polyphenols and ferric reducing antioxidant power (FRAP) were observed in pumpkin shape K712 (203.44 mg GAE/100 g FW) and K1103A (11.49 µmol Fe2+/g FW) accessions, respectively. Concerning insect resistance, 38% of studied accessions showed no infestation of green peach aphid. The kapia type K697 accession was seen as the most reliable resistance source, as it was not infested by aphids and had the least thrips (20% on plants) and cotton bollworm (6.67% on plants and 8.34% on fruit) damage. Based on examined traits, accessions were identified for enhanced fruit quality and promising insect resistance and have been included in further pre-breeding efforts.

Fruit architecture and morphology-related traits are among the determinants of fruit diversity and are major contributors to yield and yield potential in chile pepper (Capsicum spp.). This study aimed to characterize 105 genotypes of a Capsicum diversity panel consisting of cultivars, breeding lines, landrace, and wild species belonging to twelve different pod (fruit) types, for 32 morphometric Tomato Analyzer (TA) descriptors. Hierarchical cluster analysis grouped the genotypes into eight clusters based on the TA descriptors. A multivariate principal component analysis yielded two principal components, PC1 and PC2, which explained 53.24% and 10.11% of the variation in fruit diversity, respectively. The basic measurements—namely, perimeter, area, width midheight, maximum width, height midwidth, maximum height, and curved height were the most discriminating descriptors with a maximum contribution to the overall fruit shape. There was a strong, positive correlation for basic measurements and fruit shape index, whereas blockiness was negatively correlated with distal angle macro. Additive genetic effects and high heritability for the fruit traits were observed. Results of this study will provide valuable information to breed high-yielding chile pepper cultivars based on fruit morphology traits.

Teosinte is the closest wild ancestor of maize and is used as a valuable resource for taxonomical, evolutionary and genetic architectural studies of maize. Teosinte is also a repository of numerous diverse alleles for complex traits, including nutritional value and stress adaptation. Accessions including teosintes, maize inbred lines and coix were investigated for kernel protein and its association with DNA markers. The proposed investigation assumed that wild accessions had different genic/allelic content and consequently expression profile than modern maize because of the domestication syndrome and bottleneck effects. Total protein content in hard stony fruit case teosinte accessions were assessed from kernels with and without seed coats, while protein content from coix and maize lines was evaluated from kernels only. The accessions were also subjected to molecular profiling using 84 SSR markers, and obtained genotypic data were used for population structure and association analysis. The results emphasize that teosintes have higher protein content (18.5% to 26.29%), followed by coix (18.26%), and the least among maize lines (9% to 11%). Among teosintes, without-seed-coat samples had 3–6% higher protein content than with-seed-coat samples. When compared to other teosinte species, Z. mays subsp. mexicana accessions showed higher protein content, ranging from 18.62% to 26.29%. All evaluated accessions were divided into four subpopulations with K = 4, and seven significant (p < 0.01) marker–trait associations were seen with umc1294, umc1171, phi091, umc2182 and bnlg292 markers, which are distributed across chromosomes 4, 5, 7, 8 and 9, respectively. We have observed that the wild relatives carry protein content-enhancing alleles and can be used as productive donor parents in pre-breeding efforts to increase the protein content of maize.

The size and the weight of wheat grains vary across the length of each spike (Triticum aestivum L.). High temperature and water scarcity often reduce the single grain weight, and this reduction also varies across the spike length. Plants tend to cope with high temperature and drought stress through inherent mechanisms such ascanopy cooling through transpiration, which can contribute to yield stability. The effect of canopy cooling on the average grain weight at different positions in spike is still unknown. In this study, we planned to assess the role of canopy temperature, yield-related traits, and spike shape in final grain weight. For two years (2017–2018 and 2018–2019), fifteen diverse genotypes released for cultivation in different environmental conditions were grown in the field. They were examined for canopy temperature, spikelets spike−1, grain number spike−1, grain yield spike−1, and grain weight of the spike’s basal, median, and distal regions. The Pearson correlation coefficient (r) was obtained for all pair-wise combinations of traits under different treatments and spike shapes. The results indicated that cooler canopy is correlated to grain weight in normal spike shape at all three positions within the spike irrespective of stress. The advantage of the cooler canopy in improving grain-filling at basal, median, and distal regions was more conspicuous in the high temperature stress conditions compared to non-stressed and drought conditions.