Evaluation of Cold Tolerant High Yielding Oil Palm Germplasm in Guangdong Province of South China, a Northern Tropical Region

An evaluation of the vegetative growth, yield components and cold resistance traits from 38 pre-selected individual oil palm plants grown in six regions (populations) at the latitude (LAT) range between 20 degree N and 23 degree N in Guangdong Province, China was carried out during the period from April 2010 to April 2015. Analysis of variance showed significant differences in traits between the individual palms or the populations [except sex-ratio of female inflorescence and fruit bunch to female inflorescence, male inflorescence and fruit bunch (%) (SR)]. Phenotypic correlation analysis showed that bunch number (NB) was positively correlated with fresh fruit bunch (FFB), but not significantly with average bunch weight (ABW). For the individual palms, it was found that the higher the LAT the lower the frond production (FP) and LT₅₀ and the higher fruit compaction rate (FCR), and the higher the LT₅₀ the lower the ABW. For the populations, the higher the LAT the higher the ABW and the lower the abortion ratio of female inflorescence to female inflorescence and fruit bunch (%) (RAFM). Path coefficient analysis further revealed that for the individual palms ABW was the major determinant in both FFB and NB, and mainly determined by normal fruit higher per bunch (kg) (ANFW) and percent of ANFW to ABW (%) (F/B). For the populations, the major determining factors were ratio of aborted fruit bunch to fruit bunch (%) (ABR) for FFB and NB, and inflorescence (male, female, bisexual and non-anthesis) and fruit bunch numbers per year (No.) NIB and LT₅₀ for ABW. MM5 palm and Huazhou population were selected based on the major determining factors as high-yielding cold tolerant palm and population, respectively, which was consistent with the results of analysis of variance. (author)