Resistance of <i>Tectona grandis</i> To Ceratocystis Wilt

ABSTRACT Tectona grandis (teak) is a tree species highly appreciated for its high‐quality hardwood and versatile industrial applications. Despite clonal teak plantations showing several advantages, such as reduced rotation time and increased wood volume production, the genetic uniformity of plantations makes them more susceptible to diseases. Ceratocystis wilt caused by Ceratocystis manginecans has been the most prevalent disease on teak plantations, reducing tree growth rate, wood quality and value. Planting resistant genotypes is the most effective measure to mitigate losses caused by the disease. Thus, this work aimed to assess the resistance to Ceratocystis wilt of 12 teak clones commercially planted in Brazil, as well as the inheritance of resistance in teak open‐pollinated families. Five teak clones exhibited resistance to Ceratocystis wilt, and all investigated open‐pollinated teak families segregated resistance. The findings support the interpretation that resistance to Ceratocystis wilt in teak is a quantitative trait with additive gene effects in determining this trait. The information obtained in this work is an important contribution to directing the efforts of teak breeding programs in the attempt to reduce the losses caused by Ceratocystis wilt.