Presentation on theme: "PRESENTED BY:-DEEPIKA Haploids are the plants with a single set of (n) no. of chromosome in its cell. They have only the half set of chromosome."— Presentation transcript:
Haploids are the plants with a single set of (n) no. of chromosome in its cell. They have only the half set of chromosome.
Haploid plants from pollen grains were first produced by MAHESHWARI and GUHA in 1964 by culturing anthers of Datura. The technique was further develop by J.P NITCH and C. NITCH. They showed that isolated microspore of TOBACCO produce complete plants.
Haploid plants can be produced by anther culture or microspore culture. When H.Vulgare are crossed with H.Bolbosum are selectively eliminated from developing embryos. Culture of 8-10 days old embryos enable the recovery of large no. of haploid seedling in both the cases.
Hordeum vulgare (2n=14;VV) Hordeum bulbosam (2n=14;BB) × Zygote (2n=14VB) Young embryo Haploid plant of H.vulgare Diploid plants of barley
The donor plant. The composition of nutrient media. Physical factors.
The chromosome number of haploid plant is readily doubled by using colchicines the plants so obtained are called DIPLOID PLANTS. Diploid plants are completely homozygous. Homozygous lines are produced during breeding of both self and cross pollinated crops time approach takes at least 6 yrs.
PARENT AХ F1 HAPLOID PLANTS DIPLOID PLANTS SUPERIOR PROGENIES SUPERIOR PARENT B
When a cell divides by meiosis,it ends up with only half amount of DNA it had before.That is HAPLOID CELL. When two haploid join together to make one new cell with twice the amount of DNA,That is DIPLOID CELL
All the living creatures that use meiosis have to spend some time as haploid cell and some time as diploid cell. This is called alternation of generation. Some creates spend most of their time as haploid cell and only become diploid for a short time before quickly going back to being haploid again.e.g Moss
GAMETOCLONAL VARIATION:- Haploid plants regenerated from callus cultures show genetic variation i.e. gametoclonal variation. Such variation may be subjected to selection at haploid level, the chromosome no. of selected plant may be double to obtain homozygous plants.
Scheme involving extraction of dihaploids from tetraploid species, breeding level and then chromosome doubling of selected dihaploid lines to obtain tetraploid varieties.
A new technique hybrid rice varieties could boost the country rice production. For increase the country rice increase through faster development of hybrid rice varieties, agriculture science have reduced the time gap for breeding new rice varieties through the new method that is diploid breeding technique. This short time required for breeding a new variety for 10-6 yrs.
Haploids have been effectively coupled with breeding programmes of crops like rice,wheat,tobacco barley,etc.resulted in the development of several varieties. In Canada, two barley varieties, Mingo and Gwylan,produced using the H. bulbosum route were superior to powdery mildew and barley yellow mosaic virus and other yield attributes.
HAPLOID PRO- CROP VARIETIES COUNTRY DUCTION ROUTE Anther culture Rice Tanfeng 1, Xin Xiu China Hua Yu 2,Ta Be 78 Anther culture Wheat Lung Hua 1, China Jing Hua1 Anther culture Tobacco Tan Yu1
Production of homozygous DH lines using at least 4 yrs. Haploid may be useful for isolation of mutants. Diploid lines are useful tool for genome mapping. Haploid plants of F hybrid with disease resistance can be screened to develop resistance variety
In many crops, the application of this technique is not available since the technique for haploid production is not available. In many crops its application is not feasible because large no. of haploid plants are not easily obtained.