GENETIC-CONTROL OF GROWTH AND FORM IN EARLY-AGE TESTS OF CASUARINA-EQUISETIFOLIA IN ANDHRA-PRADESH, INDIA

Early results from three test plantings of Casuarina Equisetifolia spp . equisetifolia are reported: a clonal test of 40 locally selected clo nes, a progeny test of 16 wind-pollinated families of local origin, an d a family-in-provenance test of 100 wind-pollinated families which is part of an international provenance trial. All tests were planted in 1996 at the Regional Forest Research Centre, Rajahmundry, Andhra Prade sh, India. Height, stem straightness and axis persistence were measure d in the family tests at 6 and 12 months of age. The height of the clo nal test was measured at 12 months of age. Heritability estimates obta ined were ca. 0.3, 0.2 and 0.1 for height, stem straightness and axis persistence, respectively. Heritability estimates for height were reas onably consistent across the three tests; however, estimates for stem straightness and axis persistence were generally higher in the small t est of locally selected families. Height and the other two traits are most probably either weakly correlated or uncorrelated, while stem str aightness and axis persistence are positively correlated. Provenances spread across the range of natural- and land-race populations tested d emonstrated good growth potential at Rajahmundry. However, natural pro venances from Malaysia and Thailand generally showed superior growth, while the land-race populations often demonstrated superior stem strai ghtness. Based on these results some aspects of a breeding strategy ar e outlined: (a) the establishment of three unrelated sublines; (b) an initial clonal test of all parents; and (c) wind-pollinated mating wit hin clonal breeding orchards. (C) 1998 Elsevier Science B.V.