Recommended
More Related Content
Similar to Effects of domestication in the course of evolution
Similar to Effects of domestication in the course of evolution (20)
More from Brahmesh Reddy B R
More from Brahmesh Reddy B R (17)
Recently uploaded
Recently uploaded (20)
Effects of domestication in the course of evolution
- 1. Welcome GROUP B Prashantha, Megha and Brahmesh Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah
- 2. Man-made selections over natural selections Unintended effects of domestication Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah
- 3. 1a. Domestication and improvement of crops from wild species is a process of evolution that can be compared to natural selection. In this process, instead of nature being the agent that brings about adaptive changes, it is the human needs and other associated features of cultivation that shape the plant features. In the process, while some changes in plant features are very much intended and visible, there could be a lot of features that get altered unintentionally and may have become invisible. Can you list down at least a set of four such in-intended features that may have undergone changes in crop plants during domestication and explain the direction in which these changes may have taken place. 1b. Also explain how and why you think each of them may have undergone such changes during domestication The question Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah
- 4. Domestication Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah wild
- 5. Domestication Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah wild cultivation
- 6. Why domesticate? ● Isolate desired characteristics from the wild species. ● To meet the needs of human beings Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah
- 7. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah wild So what happens if domesticated?
- 8. Domestication syndrome Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah wild domesticated
- 9. The common domestication traits Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Loss of dormancy
- 10. The common domestication traits Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Larger organ size
- 11. The common domestication traits Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Reduced seed dispersal and shattering
- 12. The common domestication traits Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Uniformity in growth
- 13. The common domestication traits Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Changes to day length sensitivity
- 14. Where we succeeded Direct effects ● Increased fruit and seed weight ● Increased Palatability ● Changed plant architecture Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1093/pcp/pcac083
- 15. Traits left behind Indirect effects ● Reduced sugar content ● Reduced carotenoids ● Altered tocopherol and fatty acid content ● Reduced plant immunity ● Lower root apical dominance ● Adaptability Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1093/pcp/pcac083
- 16. Useful traits left behind A few traits escaped direct selection due to the lack of their perception by humans Loss of innate plant immunity appears to be a common feature associated with domestication in many plant species (Hajjar and Hodgkin 2007) Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah
- 17. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1007/s10681-007-9363-0 Plus signs indicate number of wild relatives that have contributed beneficial traits to crop varieties in each category of traits
- 18. Explanation for the losses The reduced frequency or complete loss of resistance alleles due to genetic drift can explain this phenomenon to some extent, especially when resistance is controlled by major gene/s in crop plants Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah
- 19. Cost of resistance Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah The wild plants were under continuous pressure from diverse pathogens, and inherent genetic resistance was a necessary defense for their fitness and survival in natural habitats.
- 20. Cost of resistance Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah In domesticated habitats, the extra care in agronomic measures and later, the application of chemicals slowly eliminated the need for natural pathogen immunity in cultivated plants. The loss of immunity during domestication should also be considered under the ‘cost of resistance’ hypothesis
- 21. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1086/285938
- 22. Fitness cost Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah keeping resistance genes may have associated fitness costs on desirable traits under selection during the plant domestication process
- 23. ● RPM1 codes for a peripheral plasma membrane protein that confers the ability to recognize Pseudomonas syringae. ● Susceptible individuals lack the entire coding region of RPM1, so there is a single susceptible allele at this locus Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1038/nature01588
- 24. RPM1+ individuals suffered a 9% decrease in total seed production relative to their RPM1- counterparts Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1038/nature01588
- 25. Fitness cost Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah For instance, certain metabolic compounds such as steroidal glycoalkaloids (SGAs), guaiacol and methyl salicylates provide chemical defense and contribute to systemic plant immunity against diverse pathogens These metabolites are also associated with undesirable fruit flavor in tomato and increase in fruit palatability by selecting against these compounds might have inadvertently compromised the host plant immunity
- 26. Fitness cost Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah A direct negative selection against fruit bitterness decreased the concentrations of 45 out of 46 SGA metabolites in domesticated compared to wild tomato accessions. https://doi.org/10.1016/j.cell.2017.12.019
- 27. Fitness cost Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Selection against seed dormancy, increased storability and dispersal, the seed carotenoid content inadvertently decreased in several widely consumed legumes including soybean, pea, common bean, peanut and chickpea
- 28. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1186/s12870-014-0385-1
- 29. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1186/s12870-014-0385-1
- 30. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1186/s12870-014-0385-1 The percentage of variation during domestication is also shown [% Δ = (D-W)/W.100] for both carotenoids and tocopherols
- 31. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1186/s12870-014-0385-1
- 32. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1186/s12870-014-0385-1
- 33. Root traits In a similar way, other unperceived plant traits shall most likely illustrate the undesirable impacts of artificial selection. Among them, root traits were neglected during the domestication of desirable above-ground plant parts, yet they differ significantly between wild and domesticated populations in different crops Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah
- 34. Wild plants are a source of key root traits that are important for adaptation under marginal conditions. For instance, wild common beans display a relatively high root apical dominance than the domesticated plants, which is an important trait under water stress conditions Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Root traits
- 35. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1104/pp.18.01509
- 36. Root traits Statistical comparisons of wild and cultivated accessions revealed highly significant differences (P < 0.01) in the RSA of young seedlings Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah
- 37. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1104/pp.18.01509 Principal component analysis (PCA) of root traits clearly shows that wild and domesticated genotypes form distinct clusters, suggesting selective forces applied during domestication significantly altered size and RSA
- 38. A change in soil habitats and direct selection of above-ground plant parts may have caused these differences in roots of these two groups. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Root traits - reason for loss
- 39. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.1093/aob/mcy221
- 40. Domesticated types achieved lower root depth per unit of biomass (i.e. root exploration efficiency), indicating that the root system of domesticated forms was more spreading than that of wild types. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Root traits - shift of focus
- 41. The domesticated types increased the depth of roots relatively more per unit of root biomass than wild types. Yet even under this drought stress the root depth per biomass unit was 60 % greater in the wild than in the domesticated types. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Root traits - shift of focus
- 42. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.15252/embj.2019103256
- 43. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.15252/embj.2019103256
- 44. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah https://doi.org/10.15252/embj.2019103256 TS-21 / TS-422 - wild (PIM type) TS-577 /670 - domesticated (BIG type)
- 45. Wild tomatoes appear to be less sensitive to salt stress than their domesticated counterparts. These traits could have been less important for domesticated plants to adapt to fertile and well-irrigated soils during the start of domestication, which led to their reduced phenotypic expression in them. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah Root traits - wild vs domesticated
- 46. Prashantha V Megha S Sogalad Brahmesh Reddy BR Unintended Effects of Domestication Department of Genetic and Plant Breeding GPB 607 (3+0) - Dr. K N Ganeshaiah open discussion
Editor's Notes
- The domestication of all major crop plants occurred during a brief period in human history about 10,000 years ago. During this time, ancient agriculturalists selected seed of preferred forms and culled out seed of undesirable types to produce each subsequent generation. Consequently, favoured alleles at genes controlling traits of interest increased in frequency, ultimately reaching fixation. When selection is strong, domestication has the potential to drastically reduce genetic diversity in a crop.
- Plant domestication underlies long-term selection on several desired characteristics of wild populations to meet the needs of early farming communities. selection had heritable effects, even in the absence of any information about the histological, biochemical, and genetic foundations of heredity. One of the major observations made by Darwin is that morphological modifications selected during domestication have been of such magnitudes that many crop plants usually cannot survive in the wild anymore without human assistance. Domestication is the outcome of a selection process that leads to increased adaptation of plant and animals to cultivation or rearing and utilization by humans
- As already alluded to by Darwin (1859), the most intensively domesticated plants have lost their ability to survive on their own in the wild. In selecting plants to fulfill their needs for food, feed, and fiber, humans have-perhaps inadvertently-selected crops that, while they do extremely well in cultivated fields, are unable to grow and reproduce successfully for more than a few seasons in natural environments, away from the care of humans who provide adequate seed beds and reducing competition from weeds
- Differences in the set of traits in cultivated and wild species, these common set of traits differentiate cultivated plants from wild ancestors are called Domestication Syndrome. The most common domesticated traits across different species include loss of dormancy, larger organ size, reduced seed dispersal and shattering, uniformity in growth and change in day length sensitivity, mainly due to their high significance for successful adaptation, easy management and higher production under cultivated environment
- Selection against dormancy: uniform germination, simultaneous flowering, uniform harvest, multiple crop cycles per year What have we lost: escaping unfavorable condition and predation, long distance dispersal, germinate after a catastrophe, uninjured when ingested by birds or animals
- Why: Desired yield correlates with sink size, improve harvest index To detoxify, ancestors used to grind and wash acorn to remove tannins. Examples of crops with reduced toxicity following domestication include cassava (Wilson and Dufour 2002) and lima bean (Vanderborght 1979). In addition to the harvest index already mentioned, other traits have played a role in influencing yield. Harvested organs in domesticated plants are usually much larger than those of their wild counterparts. For example, seeds of grain crops can be 5- to 10-fold larger than those of wild relatives. Because seed size is positively correlated with yield
- Why: easy harvest, avoid seed loss
- Why: designed expected ideotypes, easy crop management, increase harvest per unit area, simultaneous maturity and harvest
- Why: SD to LD, Help in year round production
- When we look for completeness of one trait eg. Yield, obviously others traits will get affected due Penalty of yield. Now resource allocation divided to different traits. Three thousand years ago, maize yields were approximately 0.4 t/ha. Furthermore, the initial stages of maize domestication (before 6,200 BP), which were characterized by fixation by selection of genes with major effects on the architecture of the inflorescence, may have seen initial rapid increases in seed yield. the initial domestication may have encompassed three major phases: an initial fairly rapid increase, through conscious or inadvertent selection of major genes (see below), followed by a period of several millennia with a yield stasis or limited progress in yield potential due to inefficient farmer selection, and culminating, Later only from 20th century to modern plant breeding yield has been increased.
- When cost is incurred on resistance development, what we can expect? Yield of wild species will obviously less. The idea that a plant must allocate limited resources among growth, reproduction, and defense has been central to ecological and evolutionary theories. if a plant allocates a greater proportion of resources to defense, then less should be available for growth and/or reproduction. If this relationship did not exist, then why there is polymorphisms in resistance levels?
- greater control of the genetic background increased the probability of detecting costs of resistance; there was large variation in the cost associated with the same resistance trait in different genetic backgrounds; and many examples of costs of resistance appeared to be due to linkage rather than pleiotropic effect
- Here they transferred resistant genes from different sources to susceptible ones. Our observation that genes that are transferred between species lead to a greater cost of resistance than those transferred between cultivars or biotypes (see previous section) can also be taken as evidence that linkage costs are important. Although this view contrasts with the explanation stemming from variation in detoxification systems (McKey 1979), it is the explanation typically offered by plant breeders who tend to ascribe the costs of breeding in a resistance gene from another species as a reflection of the numerous, deleterious alleles that are linked to the gene of interes