A review on double haploid breeding in modern crops
Beakal Tadesse Girma
Classical breeding introduced a number of methods for increasing of genetic gain and reduction of resources required for efficiency improvement. In this regard, the discovery of double haploid breeding in the early 20th C. is one. Double haploids are plants generated through doubling haploids. Haploids can be induced through natural and artificial means including in vivo and in vitro techniques. Spontaneous induction is preferred to be the best for the reason of not using no rigorous methods but it happens to be very rear event. The artificial methods are better in generating a greater number of progenies but they applied in limited crops and challenges like lack of endosperm with low induction rate are observed in such methods. Doubling of chromosome mostly handled by chemicals especially colchicine is widely used but it is known to be carcinogenic. Other chemicals and methods are also used but colchicine remains to be widely used. The main application of haploid breeding is shortening the breeding cycle effectively and increasing selection efficiency. It also used in reverse breeding, QTL studies and CMS generations. Although DH come up with multiple benefits, it needs high establishment cost and challenged with small amount of induction rate. Therefore, using DH breeding in combination with molecular and conventional techniques of breeding will increase it efficiency of contribution in more number of cultivated modern crops.