000			01824nam a2200217Ia 4500
008			220216s9999 xx 000 0 und d
100			_aPriyadarshan P M
245		0	_aHevea gene pool for breeding
260			_bGenetic Resources and Crop Evolution _c2003
300			_a101-114
520			_aThe conservation and utilization of allied gene resources is vital for the improvement of crop species. Rubber has been an undeniably beneficial commodity for the past 100 years. Progress in yield improvement over 70 years resulted in primary and hybrid clones with exceptional yielding abilities. The extension of Hevea to marginal areas necessitated breeding of new clones with resistance to environmental constraints. India, China, Brazil, Thailand, Cote dIvoire and Vietnam have marginal environments with single or multiple constraints such as low temperature, wind, higher altitude, moisture deficit and diseases. Allied species and accessions from the Brazil Amazonia can be integrated into such breeding programmes. Many of these clones are resultant of natural interspecific hybridizations. Also, allied species are excellent resources of timber. Molecular interventions revealed mtDNA of modern clones are highly conserved contributed by only two clones (PB 56 and Tjir 1). Nuclear DNA is highly divergent due to breeding and selection under varied geo-climates. The adaptation of allied species and wild accessions under a wide range of environments of Brazil is promising as a source of variation for breeding, and enables selection of clones for specific marginal areas.
650			_aAllied species
650			_aCytoplasm
650			_aGene pool
650			_aHevea breeding
650			_aMarginal areas
650			_aMolecular diversity
650			_amtDNA
700			_aGoncalves P de S
942			_cJS
999			_c60322 _d60322