Responses of fruit-feeding butterflies to selective logging in Sabah, Borneo

This study investigated the impacts of selective logging on tropical butterflies in lowland dipterocarp rainforest of Sabah, Malaysia (Borneo). Fruit-baited traps were used to survey butterflies in unlogged forest and forest that had been selectively logged 10 - 12 years previously in 1988 and 1989. The study focused on butterflies in the sub-families Satyrinae, Nymphalinae, Morphinae and Charaxinae (Nymphalidae). Traps were set up along four transects on existing paths and trails in unlogged forest (two transects, total length 4 km) and logged forest (two transects; total length 4 km). Traps were hung 1-2 m from the ground at 100 m intervals along transects (total of 80 traps). Traps were operated for 12 days each month. A total of 3996 adult butterflies was recorded from 63 species over a period of one year (October 1999 - September 2000). Most of the butterfly species that were present in unlogged forest were also present in logged forest. There was little difference between habitats in numbers of individuals or numbers of species recorded in Shannon-Wiener, Simpson's or Margalef's diversity indices. These results show that selective logging had little effect on butterfly species diversity 10 — 12 years after logging. There was, however, a significant difference among transects, and transects in logged forest had both lowest and highest species diversity (Shannon-Wiener). These results may be due to differences between transects in the intensity of logging. There was no evidence that selective logging resulted in the loss of butterfly species with more restricted geographical distributions. Dispersal and longevity were investigated in several of the more abundant species. Dispersal and longevity distributions fitted negative exponential functions showing that the study species were dispersing randomly and had a constant rate of survival over time. Dispersal and longevity did not differ between habitats or sexes but did differ between species in relation to body size and subfamily. The maximum distance moved by an individual in this study was 4670 m and the maximum lifespan was 175 days (B. dunya in both cases)

Phylogenetic and Morphological Characteristics Reveal Cryptic Speciation in Stingless Bee, Tetragonula laeviceps s.l. Smith 1857 (Hymenoptera; Meliponinae)

Tetragonula laeviceps sensu lato (s.l.) Smith 1857 has the most complicated nomenclatural history among the Tetragonula genera. The objective of this study was to investigate whether T. laeviceps s.l. individuals with worker bees are grouped in the same or nearly the same morphological characteristics and have similar COI haplotype cluster groups. A total of 147 worker bees of T. laeviceps s.l. were collected from six sampling sites in Sabah (RDC, Tuaran, Kota Marudu, Putatan, Kinarut and Faculty of Sustainable Agriculture (FSA)), but only 36 were selected for further studies. These specimens were first classified according to the most obvious morphological characteristics, i.e., hind tibia color, hind basitarsus color and body size. Group identification was based on morphological characteristics important for distinguishing the four groups within T. laeviceps s.l. The four groups of T. laeviceps s.l. had significantly different body trait measurements for the TL (total length), HW (head width), HL (head length), CEL (compound eye length), CEW (compound eye width), FWLT (forewing length, including tegula), FWW (forewing width), FWL (forewing length), ML (mesoscutum length), MW (mesoscutum width), SW (mesoscutellum width), SL (mesoscutellum length), HTL = (hind tibia length), HTW (hind tibia width), HBL (hind basitarsus length) and HBW (hind basitarsus width) (p < 0.001). Body color included HC (head color), CC (clypeus color), ASC (antennae scape color), CFPP (Clypeus and frons plumose pubescence), HTC (hind tibia color), BSC (basitarsus color), SP (leg setae pubescence), SP (Thorax mesoscutellum pubescence), SPL (thorax mesoscutellum pubescence length) and TC (thorax color) (p < 0.05). The most distinctive features of the morphological and morphometric characteristics measured by PCA and LDA biplot that distinguish Group 1 (TL6-1, TL6-2 and TL6-3) from the other groups were the yellowish-brown ASC and the dark brown TC. Group 2 (haplotypes TL2-1, TL2-2 and TL2-3 and TL4-1, TL4-2 and TL4-3) had a dark brown ASC and a black TC, while Group 3 (haplotypes TL11-1, TL11-2 and TL11-3) had a blackish-brown ASC, a black TC and the largest TL, FWW and FWL. As for phylogenetic relationships, 12 out of 36 haplotypes showed clear separation with good bootstrap values (97–100%). The rest of the haplotypes did not show clear differentiation between subclades that belonged together, regardless of their morphology and morphometric characteristics. This suggests that the combination of DNA barcoding for species identification and phylogenetic analysis, as well as traditional methods based on morphological grouping by body size and body color, can be reliably used to determine intraspecific variations within T. laeviceps s.l

Vertical stratification of adult mosquitoes (Diptera: Culicidae) within a tropical rainforest in Sabah, Malaysia.

BACKGROUND: Malaria cases caused by Plasmodium knowlesi, a simian parasite naturally found in long-tailed and pig-tailed macaques, are increasing rapidly in Sabah, Malaysia. One hypothesis is that this increase is associated with changes in land use. A study was carried out to identify the anopheline vectors present in different forest types and to observe the human landing behaviour of mosquitoes. METHODS: Mosquito collections were carried out using human landing catches at ground and canopy levels in the Tawau Division of Sabah. Collections were conducted along an anthropogenic disturbance gradient (primary forest, lightly logged virgin jungle reserve and salvage logged forest) between 18:00 and 22:00 h. RESULTS: Anopheles balabacensis, a vector of P. knowlesi, was the predominant species in all collection areas, accounting for 70 % of the total catch, with a peak landing time of 18:30-20:00 h. Anopheles balabacensis had a preference for landing on humans at ground level compared to the canopy (p < 0.0001). A greater abundance of mosquitoes were landing in the logged forest compared to the primary forest (p < 0.0001). There was no difference between mosquito abundance in the logged forest and lightly logged forest (p = 0.554). A higher evening temperature (p < 0.0001) and rainfall (p < 0.0001) significantly decreased mosquito abundance during collection nights. CONCLUSIONS: This study demonstrates the potential ability of An. balabacensis to transmit P. knowlesi between canopy-dwelling simian hosts and ground-dwelling humans, and that forest disturbance increases the abundance of this disease vector. These results, in combination with regional patterns of land use change, may partly explain the rapid rise in P. knowlesi cases in Sabah. This study provides essential data on anthropophily for the principal vector of P. knowlesi which is important for the planning of vector control strategies

Butterfly dispersal and longevity in unlogged and selectively logged forest

This study investigated butterfly dispersal and longevity in unlogged and selectively logged forest in lowland dipterocarp rainforest Sabah, Malaysia (Borneo). Fruit-baited traps were used to survey butterflies in unlogged forest and forest that had been selectively logged 10-12 years previously in 1988 and 1989. The study focused on butterflies in the subfamilies Satyrinae, Nymphalinae, Morphinae and Charaxinae of the family Nymphalidae. Traps were set up along four transects on existing paths and trails in unlogged forest (two transects, total length 4 km) and logged forest (two transects, total length 4 km). Traps were hung 1-2 m from the ground at 100 m intervals along transects (total of 80 traps). Traps were operated for 12 days each month (October 1999-September 2000). Dispersal and longevity were investigated in several of the more abundant species. Dispersal and longevity were investigated in seevral of the more abundant species. Dispersal and longevity were investigated in several of the more abundant species. Dispersal and longevity did not differ between habitats or sexes but did differ between species in relation to body size and subfamily. The maximum distance moved by an individual in this study was 4670m and the maximum lifespan was 175 days (Bassarona dunya in both cases)

Phylogeography of Mycalesis roses (Lepidoptera: Satyrinae) in Sabah, Borneo based on nested clade analysis of mitochondrial DNA variation

The main objective of this study was to investigate the phylogeography of Mycalesis orseis Fruhstorfer 1906 on Borneo using nested clade analysis of mitochondrial DNA variation. Nine individuals of adult M. orseis were collected from each of the 10 study sites: two sites in contiguous forest (Maliau, Danum) and eight sites in fragments of different sizes (Tabin, Tawau Hill, Lungmanis Virgin Jungle Reserve (VJR), Sepilok VJR, Keruak VJR, Ulu Sapa Payau VJR, Sg. Sapi VJR, Labuk VJR). MtDNA from thoracic material was analysed using ‘George’ and ‘Btyls’ primers from a 796bp sequence on the cyctochrome oxidase II (COII) gene. The significant associations between clades and geography observed in this study were only detected within the 0-step clade level of the nested analysis. The lack of any significant effects at any other levels of the nested clade analysis indicated very recent gene flow and historical associations among subpopulations of M. orsei

Kajian tentang status kerintangan insektisid terhadap Plutella Xylostella, perosak utama sayur-sayuran Cruciferae di Kundasang, Sabah

Kajian ini dijalankan bertujuan untuk mengetahui status kerintangan insektisid terhadap larva Piute/la xylostella terhadap bahan aktif insektisid Cypermethrin, Spinosad, Avermectin, Chlorantraniliprole, Chlorfenapyr, Tolfenpyrad dan Lufenuron. Kajian ini telah dijalankan selama dua (2) tahun bermula pada tahun April 2013 - April 2015 menggunakan peruntukan Universiti Malaysia Sabah (SBK0136-STWN-2014). Tinjauan terhadap penggunaan insektisid oleh 40 responden yang mengusahakan ladang-ladang sayuran juga dilaksanakan bagi mengetahui hubungkait kerintangan insektisid dengan cara penggunaan insektisid di Kundasang. Kajian ini telah dilaksanakan di makmal dan ladang Fakulti Pertanian Lestari (FPL) UMS (Sandakan) yang merangkumi tiga peringkat iaitu i. penanaman kobis yang bebas dari serangan insektisid, ii. persampelan larva P. xylostella di Kundasang dan iii. ujian bioasai celup daun. Faktor Kerintangan Cypermethrin (FR > 160), Avamectin (FR > 10.1 - 40.0), Chlorantraniliprole (FR > 160) dan Chlofenapyr (FR > 160) adalah pada julat sederhana rintang hingga amat rintang. Cypermethrin dan Avamectin adalah bahan aktif insektisid yang telah direkodkan penggunaannya seawal tahun 1990an. Spinosad, Tolfenpyrad, Lufenuron, Chlorantraniliprol

Efficacy of column hydroponic system for increasing growth and yield of pak-choy (Brassica rapa L.) per unit area

Increasing the domestic production of Brassica vegetables is important to sustain the local food supply, maintain the healthy diets of the population, reduce the country's foreign exchange, and improve the local economy. In this study, a column hydroponic system (CHS) of 1.2 m L 1.2 m W 1.5 m H was built and tested to increase Brassica vegetable production per unit area. There were 16 rectangular polyvinyl chloride tubes (10.2 cm L 5.1 cm W 1.5 m H) positioned upright (PVC columns) at 30.0 cm apart in four rows. Each column had 36 planting cups (4 lines 9 levels). The seeds of curly dwarf Pak-choy were germinated on mop yarns in the cups. The nutrient solution was supplied using a 0.5HP non-submersible pump. Data were recorded on day 37 by measuring the vegetable yield, development, growth, and quality. The data were analyzed using Microsoft Excel®2019 by performing one- and two-way ANOVAs, followed by posthoc tests ( = 0.05). The vegetable yield/area of the CHS (12.7 kg/m2 , or 400 plants/m2 ) was 60% higher than that of a raft hydroponic system (5.1 kg/m2 , or 63 plants/m2 ), but the mean weight/plant was 62% lower than that of the latter system (31.3 g/plant vs. 82.1 g/plant). There were statistically significant (P < 0.05) effects of column horizontal position (CHP) or vegetable vertical location (VVL) on the parameters studied. However, the effects of CHP VVL was statistically significant only on yield and leaf area. Pak-choy in outer columns facing the morning and afternoon sunlight directly or at the top were heavier (39.2 - 71.7 g/plant) than those in inner columns or at the bottom (8.8 - 20.3 g/plant). The CHS can be used effectively to increase Brassica vegetable production/area, but its full potential is yet to be achieved. Research is recommended to determine the ideal column spacing to achieve the best balance between plant/area and weight/plant to increase further the system's growth, yield, and quality of vegetables

Linking Measure of the Tropical Stingless Bee (Apidae,Meliponini, and Heterotrigona itama) Honey Quality with Hives Distance to the Source of Heavy Metal Pollution in Urban and Industrial Areas in Sabah, Borneo

Honey is a natural product of bees, and its chemical composition depends on the nectar sources of the surrounding flora as well as environmental factors. However, keeping hives in areas polluted with heavy metals can affect the quality of bee products such as honey. To date, there have been very few studies on the health risks of consuming honey at various locations in the Malaysian state of Sabah, Borneo, in relation to food standards and heavy metal contamination of honey from the stingless bee, Heterotrigona itama in association with pollutant sources. A total of 63 samples of raw and unprocessed honey were collected directly from beekeepers producing honey at five sites in the industrial areas. All selected heavy metals were measured using an inductively coupled plasma optical emission spectrophotometer (ICP-OES). Overall, the most frequently detected element was Zn (0.090 mg/kg), followed by Pb (0.012 mg/kg), As (0.004 mg/kg), and Cr (0.003 mg/kg), while Cd (0.001 mg/kg) was the lowest element in honey from all areas. With the exception of Cr and Zn, a significant correlation was found between PCA factor score 1 and heavy metal concentration in honey for Pb, Cd, and As, suggesting that the source of pollution for these metal elements was from hives closer to major roads, cities/town, petrochemical hub, and power plants. Although the heavy metal concentrations in the honey samples did not exceed the food standard limits and therefore do not pose a health risk, the observed increase in heavy metal concentrations in honey in industrial areas could pose a potential risk in the future due to the growing interest in rearing of stingless bees for honey production in these areas of Sabah

Growth, Yield and Economic Potential of Cavendish Banana Planted in Oil Palm Gaps

The mortality of a few trees leads to the emergence of palm gaps or unproductive areas in oil palm plantations. These areas offer the potential for integrating a secondary crop, such as, the Cavendish banana (Musa acuminata Colla). This banana is a well-established clonally propagated variety which is well known to local planters, but to date, little information is reported about its agronomy, yield, management, and economic potential as an intercrop in oil palm plantations. In the present study, Cavendish suckers were planted in palm gaps and the respective information was assessed. The suckers were collected from the mother plants in Kota Belud, Sabah. The suckers were planted in polybags for conditioning, and after a month, transplanted at 1.8 m 1.8 m distance in palm gaps of the oil palm area in UMS Campus, Sandakan. The planting density was 10 saplings/(2.3 m x 6.0 m) gap. Weeds were machine-cut in the first 11 months, but after that, only when necessary. The weeds were also controlled with application of Glyphosate once/year. Fertilizer was applied once/year as 0.5 kg of NPK15:15:06, NPK15:15:15, and NPK12:12:17, respectively. Compost was added once/year as 1.5 kg of chicken dung and goat manure, respectively. Trees yielded fruits within seven to eight months of transplantation. The banana trees were 2.2±0.2 m tall at fruiting. The yield was 14.6±0.2 kg banana-hand/bunch. The banana hands were 2.0±0.1 kg/hand. There were seven banana hands per bunch, with a weight that ranged from 3.29±0.22 kg (top), 1.92±0.05 kg (middle) to 1.37±0.19 kg (bottom/last) per hand. The banana hands were sold at RM4.0/kg. The profit was RM56.0/bunch, or RM4.06/m2 /banana. The net profit was RM40.39/banana, or RM29.26/m2 , not accounting fruit processing and marketing costs, which was not so applicable in this study. In addition, the banana foliage shaded and thereby suppressed the growth of weeds, reducing the manpower and associated cost of weeding in the oil palm area