Title : Tree breeding for development of triploid hybrid in leucaena leucocephala to resolve wood sustainability in India
Abstract:
Subabul (Leucaena leucocephala) is native to Central America and Mexico, but now grows naturally in most tropical areas globally. It is one of the pulpable species globally which plays a prominent role in paper and pulp industry in India. As of today, Leucaena leucocephala plays important role such as fodder, green manure along with also being nitrogen fixing from atmosphere and has reduced the use of chemical fertilizers and have enhanced soil fertility. Leucaena leucocephala today is one of the major pulp sources for production of writing printing papers, newspaper and packaging board which is used in daily human lifestyles. This two-way transaction has been proven beneficiary for both farmers and Company.
Leucaena leucocephala is grown in Prakasam and Krishna District of Andhra Pradesh alongwith Gujarat, Maharashtra and Orissa. It is well distributed in all the geographical locations in India and tropical countries of the world. Approximately 3 million MT Leucaena leucocephala wood is being procured by the paper industries from North & South Andhra Pradesh, Gujarat, Maharashtra and Telangana with turnover of 146 million dollar per annum.
The total Leucaena leucocephala plantation is spread over 50000 Hectare generates 3 million mandays for 18 Million dollar for harvesting and 150 thousand trucks amounting 72 million dollar for transportation of wood from plantation areas to major paper industries in India. The business turnover by Leucaena leucocephala wood is 235 million dollar. If the similar wood quantity is replaced by other species imported pulpwood, then total additional amount of 353 million dollar is required.
Leucaena leucocephala is most suitable species for pulpwood and mass scale propagation can be done through seeds and clonal plants by vitro and vivo technologies. The Leucaena leucocephala plant has profound characters of higher seed production which spreads nearby fields for natural germination in others agriculture field which is a main restrictive cause for Leucaena leucocephala plantation, and more energy is moved to seed production which can be diverted to wood production by producing sterilized plant, which has been addressed by breeding and hybridization by development of triploid species. A hybridization program was initiated to enhance wood production plus disease and pest resistance clones/hybrids.
- Leucaena leucocephala (2n)-104 Chromosomes. L. leucocephala is a highly self-compatible tetraploid (2n = 4x = 104) and has a relatively narrow genetic base.
- Leuceana collinsii diploid (2n)-52 Chromosomes, L. collinsii is high resistance to psyllids, tolerance to cold temperatures and good wood qualities.
After breeding between two parents hybrid has been developed which was further confirmed for hybridity by the DNA fingerprinting test and the hybrid seeds were released for progeny trial in that the volume increment has shown vigorous growth of seedless Leuceana leucocephala and the seedless variety was released for commercial production by vitro and vivo technologies for mass multiplication and pulpwood plantation in India.
