Tiêu đề GPB-355 Objectives.pdf ✅

Course no-GPB 355 Course Title-Crop Improvement 1. The sum total of genes in a crop species is referred to as genetic resources 2. Gene pool refers to a whole library of different alleles of a species. 3. Germplasm may be defined as the sum total of hereditary material i.e.; all the alleles of various genes present in a crop species and its wild relatives. 4. CBD -Convention on Biological Diversity 5. Land races: These are nothing but primitive cultivars which were selected and cultivated by the farmers for many generations without systematic plant breeding efforts 6. Obsolete cultivars : These are the varieties developed by systematic breeding effort which were popular earlier and now have been replaced by new varieties. 7. Improved varieties of recent past are known as obsolete cultivars 8. The currently cultivated high yielding varieties are referred to as modern cultivars. 9. Advanced lines - These are pre -released plants which have been developed by plant breeders in modern scientific breeding programmes. 10. Wild relatives or wild species naturally occurring plant species which have common ancestry with crops and can cross with crop species are referred to as 11. Types of gene pool: 1. Primary gene pool 2. Secondary Gene pool 3. Tertiary gene poo 12. The gene pool in which intermating is easy and leads to production of fertile hybrids is known as primary gene pool 13. The genetic material that leads to partial fertility on crossing with GP1 is referred to as secondary gene pool. 14. The genetic material which leads to production of sterile hybrids on crossing with primary gene pool is termed as tertiary gene pool or gene pool three 15. Types of seed collections: 1. Base collections 2. Active collections 3. Working collections 16. Base collections are stored at about -18 °C or -20°C with 5 + 1% moisture content 17. Active collection are stored at temperatures below 15°C (often near °C), and the seed moisture is kept at 5%. The storage is for medium duration, i.e., 10-15 years 18. Working Collection are stored for 3-5 years at less than 15°C and they usually contain about 10% moisture. 19. Core collection refers to a subset of base collection which represents the large collection. 20. Exploration refers to collection trips and collection refer to tapping of genetic diversity from various sources and assembling the same at one place. 21. Conservation refers to protection of genetic diversity of crop plants from genetic erosion. 22. Conservation methods : 1. In situ conservation 2. Ex situ conservation
23. In situ conservation Conservation of germplasm under natural habitat is referred to as in situ conservation. Eg natural park, biosphere reserve or gene sanctuary. 24. NBPGR,:National Beaureau of Plant Genetic Resources 25. Ex situ conservation: Conservation of germplasm away from its natural habitat is called ex situ germplasm conservation. 26. Orthodox Seeds: Seeds of this type can be dried to low moisture content of 5% and stored at a low temperature without losing their viability . E.g. Wheat, Rice, Corn, Chickpea, Cotton, Sunflower 27. Recalcitrant seeds: The viability of this group of seeds drops drastically if their moisture content is reduced below 12-30%. Eg Citrus, cocoa, coffee, rubber, oil palm, mango, jackfruit, etc. 28. Evaluation refers to screening of germplasm in respect of morphological, genetical, economic, biochemical, physiological, pathological and entomological attributes. 29. Documentation It refers to compilation, analysis, classification storage and dissemination of information 30. Utilization It refers to use of germplasm in crop improvement programmes. 31. Organizations associated with germplasm - IPGRI – International Plant Genetic Resources Institute NBPGR – National Bureau of Plant Genetic Resources 32. Genetic erosion refers to loss of genetic diversity between and within populations of the same species over a period of time. 33. The flower is the reproductive unit in the angiosperms. 34. Calyx and corolla are accessory organs, while androecium and gynoecium are reproductive organs. 35. When a flower has both androecium and gynoecium, it is bisexual. 36. A flower having either only stamens or only carpels is unisexual 37. When a flower can be divided into two equal radial halves in any radial plane passing through the centre, it is said to be actinomorphic, e.g., mustard, datura, chilli. 38. When a flower can be divided into two similar halves only in one particular vertical plane, it is zygomorphic, e.g., pea, gulmohur, bean, Cassia. 39. A flower is asymmetric (irregular) if it cannot be divided into two similar halves by any vertical plane passing through the centre, as in canna. 40. In the hypogynous flower the gynoecium occupies the highest position while the other parts are situated below it. 41. The ovary in hypogynous such flowers is said to be superior, e.g., mustard, china rose and brinjal. 42. If gynoecium is situated in the centre and other parts of the flower are located on the rim of the thalamus almost at the same level, it is called perigynous. The ovary here is said to be half inferior, e.g., plum, rose, peach. 43. Epigynous flowers, the margin of thalamus grows upward enclosing the ovary completely and getting fused with it, the other parts of flower arise above the ovary. 44. In epigynous flower the ovary is said to be inferior as in flowers of guava and cucumber, and the ray florets of sunflower
45. The calyx is the outermost whorl of the flower 46. The members of calyx are called sepals. 47. Aestivation: The mode of arrangement of sepals or petals in floral bud with respect to the other members of the same whorl. 48. Removal of stamens or anthers or killing the pollen of a flower without the female reproductive organ is known as emasculation 49. Chemical hybridizing agents (CHA) or gametocides : Ethrel, Sodium methyl arsenate, Zinc methyl arsenate in rice, Maleic hydrazide 50. Pollination refers to the transfer of pollen grain from anthers to stigmas. 51. Self pollination- It is transfer of pollens from and to the stigma within the same flower, is always found in bisexual flower 52. Bisexuality: Male and female sexual organs present in the same flower e.g. Wheat, rice, groundnut, etc. 53. Homogamy: Male and female sexual organs mature at the same time e.g. wheat, groundnut, etc. 54. Cleistogamy: In this condition flowers does not open at all and ensure complete self-pollination e.g Oat, Barley, Wheat, Grasses, etc. 55. Chasmogamy: In some species, flower open but only after pollination has taken place. e.g Barley, Wheat, Oat, and many cereals 56. Cross Pollination: The transfer of pollen from a flower to the stigma of the other flower of different flower plant. 57. Dicliny (Unisexuality): It is a condition in which flower is either staminate or pistilate. a)Monoecy: Staminate and pistilate flowers occur in the same plant either in the same inflorescence. e.g. Mango, banana, coconut or in the separate inflorescence. e.g. Maize, Cucurbit, Strawberry, etc. 58. Dioecy: The male and female flowers are present on different plants i.e. the in such species are male or female i.e. sec is governed by a single gene. E.g. Papaya, hemp, date, palm, etc. 59. Dichogamy: Anther and stigma of hermaphrodite flower mature at different time, facilitating cross pollination. 60. Protogyny: Gynoecium matures earlier than the androecium e.g. Bajara. 61. Protandry: Androecium matures earlier than gynoecium. e.g. marigold, maize, cotton, etc 62. Heterostyly: Different length of style and filaments e.g. Linseed 63. Herkogamy: Presence of physical barrier or mechanical obstacles between the anther and stigma ensures cross pollination. 64. Self –Incompatibility: It refers to the failure of pollen from a flower to fertilize the same flower or other flowers on some plants. It may be saprophytic or gametophytic e.g. mustard, tobacco, sunflowers, reddish. 65. Male Sterility: It refers to the absence of functional pollen grains in hermaphrodite flower. 66. Expressivity The degree of phenotypic expression of a penetrant gene is called expressivity.
67. The frequency with which a gene produces a phenotypic or visible effect in the individuals, which carry it, is known as penetrance. 68. Plant introduction is the process of introducing plants/ genotype or group of genotypes into new environment where they were not being grown before. 69. Acclimatization The process that leads to the adoption of a variety to a new environment. 70. The concept of pure line was proposed by Danish botanist Johannsen in 1903. 71. Pure Line: It is the homogeneous progeny of single self-pollinated homozygous plant. 72. Pure Line Selection: development of new variety through identification and isolation of single best plant progeny. 73. Bulk population method of breeding in self –pollinated crop is also known as mass method or population method of breeding. It was first used by Nilsson Ehle in 1908. 74. Marker Assisted Selection [MAS] refers to indirect selection for a desired plant phenotype based on the banding pattern of linked molecular (DNA) markers 75. Method of Gene transfer A. Indirect Gene transfer method 1.Transformation (Agrobacterium spp) B. Direct Gene transfer method i. Transfer via Electroporation ii. Transfer via Polyethylene Glycol (PEG) iii. Transfer via Biolistics:( Particle bombardment method) iv. Transfer via Microinjection v. Liposome Mediated Gene Transfer 76. Restriction enzyme and ligase, play the most significant role in the process of trans-genesis. 77. PEG- Polyethylene Glycol 78. AFLP -Amplified fragment length polymorphisms 79. RFLP -Restriction fragment length polymorphisms 80. RAPD- Random amplified polymorphic DNA 81. SSR -Simple sequence repeats 82. SNP -Single nucleotide polymorphisms 83. Molecular markers are not affected by environmental conditions. 84. MAS leads to development of non-transgenic genotypes or cultivars. 85. Agarose gel electrophoresis is stained with ethidium bromide. 86.Stress: Constraining influence, force, pressure or adverse conditions for crop growth caused by biological or environmental factors. 87. Biotic (living): Adverse effects due to pests and diseases 88. Abiotic stresses Abiotic (nonliving): Adverse effects on host due to environmental factors eg: Drought, water logging, heat, cold, salinity, alkalinity and air pollution etc. 89. Host: Plant affected by a disease or which can accommodate pathogen. 90. Pathogen: An organism that produces the disease