Objectives of Plant Breeding

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Major Objectives of Plant Breeding Program Plant breeding is an important branch of agricultural science. Its main purpose is to develop new and improved crop varieties. These improved varieties give better yield, better quality, and better resistance against diseases and harmful environmental conditions. A plant breeding program is planned according to the needs of farmers, consumers, industries, and climate. The major objectives of plant breeding are explained below in simple paragraph form. 1. Higher Yield The first and most important objective of plant breeding is to increase crop yield. Food demand is increasing due to rapid population growth, so breeders try to develop varieties that produce more grains, fruits, seeds, or biomass per unit area. High-yielding varieties help farmers earn more profit and improve food security. This is why yield improvement is considered the central objective of every breeding program. 2. Improved Quality Another major objective is to improve t...
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Ascobolus Character

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Sample F1

Characteristics:

 1.  The thallus is made of richly branched mycelium that forms a complex structure and finally a cup shaped structure.

2. The hyphal masses penetrate the substratum. These act as organs of absorption for the aerial branches.

3. The hyphae are branched and septate. Each cell is multinucleate.

4. The male reproductive organs are antheridia and the female reproductive organs are called ascogonia.

5. Antheridia and ascogonia are borne at the tips of separate branches.

6. Antheridium is borne at the tip of antheridial branch. It is cylindrical or clavate in shape.

7. Each antheridium is multinucleate.

8. Ascogonium is also present at the tip of the ascogonial branch. It is sub-globose in shape and is multinucleate.

9. The ascocarps are apothecia and develop as a result of fertilization.

10. These are yellowish and saucer shaped.

11. Apothecium is a cup-shaped structure that is made of mycelium.

12. The section shows three zones-the outermost called hymenium, the middle called subhymenium and the lowermost called hypothecium.

13. The lowermost hypothecium, is made of sterile hyphae, loosely packed to form pseudoparenchymatous region called trama.

14. The middle zone consist of a few erect hyphae.This later merges with hymenial layer which is called sub-hymenium.

15. The hymenium consists of asci intermingled with paraphyses.

16. The asci elongate on maturation to protrude above the hymenial surface. These are found mixed with paraphyses. Ascus is a long and cylindrical structure. It opens by a terminal pore called operculum.

17. Each ascus contains eight ascospores. Ascospore is one celled, large in diameter, purple or dark brown and the spore wall shows longitudinal colourless striations.

.........................................................Hence it is Ascobolus.




Systematic Position:

Kingdom-Mycota

Division-Eumycota

Sub-division-Ascomycotina

Class-Discomycetes

Order-Pezizales

Family-Pezizaceae

Genus-  Ascobolus






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