Genetic Diversity and Correlation Among Agronomic Traits of Temulawak (Curcuma xanthorrhiza Roxb.) under Rubber Plantation Shade

Abstract

   Temulawak (Curcuma xanthorrhiza Roxb.) is a well-known medicinal plant and widely used as tradi­tional medicine in Indonesia.  Development of temulawak cultivation is suggested to be conducted under shading area such as under rubber plantation. Information on genetic variability and relationship among agronomic and metabolite traits under shading area will support the selection process of temulawak breeding by providing heritable traits which correlated to a main trait.  This research aimed to provide information of genetic variability and correlation among traits which will be useful for the temulawak breeding program.  Temulawak cultivation were conducted under six location of PT Perkebunan Nusantara VIII rubber plantation, West Java which consisted of two altitudes. Those were low altitude (Cikumpay, Cipeo, Pasir Salam) and medium altitude (Gunung Hejo, Gunung Nyungcung, Mengger).  Randomized complete block design and 11 temulawak genotypes (A, D, F, T4, T5, T6, T11, T12, T14, T16, T17) was used in each location.  Result showed different location affected almost all traits. High heritability and medium coefficient of genetic variation performed by primary rhizome fresh weight (h²_bs=74,8%), total rhizome fresh weight (h²_bs=66,8%), leaves width (h²_bs=62,2%), secondary rhizome fresh weight (h²_bs=57,9%), tiller number (h²_bs=56,5%) and stem girth (h²_bs=53,5%).  Path analysis result revealed that plant height (r=1,877) and tiller number (r=0,915) directly correlated with total rhizome fresh weight.  However only tiller number is recommended as selection trait of total rhizome fresh weight because of its high direct effect and high heritability.

Keywords: heritability, metabolite, path analysis, rhizome, selection trait.