อัตราพันธุกรรมและสหสัมพันธ์ของลักษณะทางการเกษตรในปาล์มน้ำมันลูกผสมเทเนอรา

Abstract

Oil palm is a more economically important crop, in terms of oil yield than other oil crops. Tenera oil palm is a commercially popular variety in Thailand. Some breeders to base population by selecting parents in germplasm collections to create hybrids that have adaptations to the natural environment, resistance to diseases, a large fresh fruit bunch, and high oil yield. The objectives of this study were to analyze variance, -estimate broad-sense heritability (h?), phenotypic correlation coefficient (rp) and path analysis among vegetative characteristics, oil yield, bunch yield and bunch components of four- year old tenera oil palm varieties. The chosen varieties were Nongped (NP), Surat Thani 2 (ST2), Golden Clonal Tenera (GT), Yangambi (YG), Prince of Songkhla University (PSU-1) and Univanich (UN), and were planted at Oil Palm Collection Center, The Chaipattana Foundation, Trang. The experiment was arranged in a randomized complete block design (RCBD) with three blocks, with data collect every four months for one year. The results showed significant differences of vegetative characteristics among varieties except height (H), which was not significantly different. Coefficient of variation (C.V.%) ranged from 2.16 - 5.61%. The UN gave the best mean of vegetative characteristics, with second best being the PSU-1. The oil yield, bunch yield and bunch components had no significant differences among varieties, except the height bunch number (BN), average bunch weight (ABW), average kernel weight (AKW), kernel/bunch (K/B) and kernel/fruit (K/F), which were significantly different, and the C.V. ranged from 8.28 - 16.66%. The YG gave the highest mean oil yield (OY), fresh fruit bunch (FFB) and BN, while the UN had the most bunch components. Broad-sense heritability values of vegetative characteristics were moderate to high (h, = 44.82 - 90.91%) of which leaflet length (LL), leaf area (LA), rachis length (RL), petiole width (PW), petiole depth (PD) and leaf dry weight (LDW) were high. The broad-sense heritability values correspond to the ratio to genotypic coefficient of variation and phenotypic coefficient of variation (GCV/PCV). Phenotypic correlation coefficient and path analysis, characteristics had a positive significant phenotypic correlation with ABW including LA, PD and LDW (f, = 0.69** 0.55* and 0.49*, respectively), and had high direct and/or indirect effects. Broad-sense heritability values of BN, ABW, K/B and K/F were high (h, = 62.98 - 69.91%), while average fruit weight (AFW), AKW and wet mesocarp/fruit were moderate (h, = 36.31 - 58.34%). The characteristics of oil yield, bunch yield and bunch components had a positive significant phenotypic correlation and direct effect on FFB including BN (r, = 0.75 **). Fruit/bunch (F/B), oil/wet mesocarp (OWM) and oil/fruit (O/F) had a positive significant phenotypic correlation and direct and/or indirect effects on oil/bunch (O/B) (rp = 0.56*, 0.82** and 0.98**, respectively). The characteristics were positive phenotypic correlation and direct and/or indirect effects on OY including FFB and O/B (r, = 0.79** and 0.34, respectively). Moderate to high broad-sense heritability was used in conjunction with phenotypic correlation coefficient and path analysis, to assist with identification of characteristics that are useful as selection criteria, or high efficiency improvement of oil palm.