Evaluation of Genotype x Environment Interaction on Morphological Characteristics of Eight Selected Labisia pumila var. alata Clones (Kacip Fatimah) by Francis and Kannenbergs Method

Labisia pumila or locally known as Kacip Fatimah is a native plant of Malaysia that commonly found in shady areas of the Forest Reserve at elevations of 80 to 100 m or more. Labisia pumila that fall under family Myrsinaceae also are recognized and identified locally as Selusuh Fatimah, Rumput Siti Fatimah, Akar Fatimah, Pokok Pinggang, and Belangkas Hutan. This herb has been selected as one of the five main herbs under initial phase of the Entry Point Project (EPPs) that implemented through National Key Economic Areas (NKEAs). This project is focused towards improving the product quality and marketing efforts of dietary and herbal supplements to tap the global demand for high-value herbal supplements and remedies. This showed that L. pumila getting high demanded from local as it can be treat variety of ailments [4]. Traditionally, the whole L. pumila plants are boiled in water and taken as orally for easing the childbirth. Recently, this herb is sold commercially in the form of herbal tea, powder, capsules and tablets in many countries [2]. The demand to this herb is increased through all the year as many researchers found it have anticancer, antioxidant, anti-osteoporosis and anti-inflammatory properties [8][6]. 

However, raw materials for product development and local uses is not sufficient due to less contribution of the local farmer to cultivate this herb. According to [1] in Globinmed database, less than 10% of the raw materials are cultivated locally. The rest are either imported from overseas or collected from the wild. This situation will lead to adulteration with low quality materials. Since this species are not yet produce locally, it is important for this species to undergo the testing at different environment at different location so that only variety or clones that has good mean performance over a wide array of environments can be identified and introduced to the Malaysia farmer. In other means, the selected clones of L. pumila produced are genetically superior and genetically stable.

Since cultivation L. pumila needs the most critical environmental conditions such as heavy shade which a least 60%, high soil humidity and no water logging, it is probably exposed to the influence of Genotype x Environment (GxE) Interaction. Sprague [9] indicated that GxE interaction constitutes an important limiting factor in the estimation of variance components and in the efficiency of selection programmes. The presence of a significant GxE interaction for morphological characteristics of L. pumila either in plant height, leaf number, leaf length, leaf width and collar region will bring a problem for selecting superior genotypes for elite clones. According to [3], the presence of GxE interaction also disturb the relative performance of genotypes in different environments. Some genotypes will perform well in few environments and very poor in other environments, showing better mean performance across environments. In other cases, some genotypes may have average performance which is more stable over wide environments. Thus, it is important to conduct the evaluation of GxE interaction in order to track the pattern and magnitude of GxE interaction for better understanding of the response of different genotypes to varying environments. For non-significant effect, the stability analysis also will be further analyze for identification of stable and widely adapted and unstable but specifically adapted genotypes. This analysis is so important for clone and variety recommendation. A stable L. pumila clones will be selected if it has capable of utilizing the resources available in high yielding environments and has a mean performance that is above average in all environments.

 As an easy way of interpretation of responses of genotypes to environmental variation, non-parametric approach was used as it have some advantages over the parametric approach. This approach separates genotypes based on their similarity of response to a range of an environment. This essential information is required for many applications such as selection in plant breeding programs and cultivar testing trials.

 The objectives of this study were to i) determine the magnitude of genotype x environment interaction for plant height, leaf number, leaf length, leaf width and collar region; ii) to identify stability of genotypes respective to plant growth characteristics evaluated.