Flowering, fruiting, seed germination and seedling growth of Macaranga gigantea

Abstract

The stages of flower and fruit development of Macaranga gigantea, its seed germination behavior in nature and from fruit harvesting, as well as the process of raising its seedlings in the laboratory were studied to determine the potential for production of M. gigantea seedlings. Five reproductive trees of M. gigantea were chosen as sources of seed. To estimate natural germination rates, four sample plots of 1 x 1 m 2 in four cardinal directions below the crown of every tree were set up. In addition, dry and wet extraction processes were carried out to determine, which the more effective method for germination of M. gigantea seeds. The results showed that the time required from flower development to fruit ripening in M. gigantea flowers was 5-6 months. The flower buds initiated in the dry season (August 2011) and the fruits ripened in the rainy season (December 2011-January 2012). The seeds that fell under the parent tree germinated in approximately 24 days with an average seedling density of 75-267 per m 2. The germination in laboratory showed that the percentage and the rate of germination of the seeds extracted through the wet extraction process were higher than those extracted through the dry extraction process. The highest rate of germination (65%) is by the combination of seeds extracted through wet extraction process and grown on compost media. The relative growth rate of seedlings planted on mushroom spawn waste media was the highest rate (0.36 0.42%), followed by those planted on compost media (0.150.09%), top soil media (0.100.04%) and sand media (0.100.07%).

Comparative Vessel Traits of Macaranga Gigantea and Vatica Dulitensis From Malaysian Borneo

“…Dense vessels lower the risk of detrimental damage during stressful environmental conditions by enabling alternative pathways for water conductivity when cavitation occurs (Schmitz et al 2006). Vatica dulitensis is a slow-growing shade-tolerant species (Still 1993), and its vessel traits are unlikely to need a high hydraulic efficiency to support rapid transpiration. Instead they would ensure high hydraulic safety during occasional droughts when soil moisture is limiting.…”

Effect of organic manure fertilizer on the growth of Macaranga gigantea

“…gigantea seedlings were collected from wildlings (wild seedlings) grew under host tree at Botanical Garden of Mulawarman University, Samarinda. Wildlings with similar size were collected and placed on wet newspapers, carried to nursery and transferred into polybags (Susanto et al 2016a). These seedlings were covered for one month to maintain its moisture.…”

Nutrient distribution on soil and aboveground biomass of Macaranga gigantea five years after planting

“…The plant reproduces by forming flower buds initiated in the dry season and the fruits ripened in the rainy season. The seeds that fell under the tree germinated in approximately 24 days (Susanto et al 2016a). Bentos et al (2008) also reported that the flowering of pioneer trees happening at the end of the dry season and fruiting happening at the beginning of the wet season.…”

“…Mindawati et al (2010) also reported that soaking the seeds into 0.2% potassium nitrate solution for 20 minutes before germinate on sand medium able increasing seed germination rates up to 20%. On the other hand, Susanto et al 2016a reported that wet extraction without fruit drying treatment, able increased seeds germination (65%), with germination time first seeds (GTFS) 7.67 ± 1.15 days, germination time last seeds (GTLS) 17.33 ± 4.04, and mean germination times (MGT) 11.97 ± 1.93 days. In the germination process of M. gigantea seedlings showed that the highest relative growth rate obtained by seedlings planted on mushroom spawn waste media, followed by compost media, top soil media, and sand media.…”