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In Southeast Asian forests, there are dramatic supra-annual peaks in fruit availability known as mast fruiting, followed by low-fruit periods. Gibbons are frugivorous small apes. In this study, we investigated how gibbons varied their social and calling behaviors in response to changes in fruit availability. Activity budget, travel distance, sleeping time, and song duration of two wild Northern Gray gibbon (Hylobates funereus) groups were investigated during both mast and non-mast fruiting periods at the Danum Valley Conservation Area, Sabah, Malaysia. Gibbons traveled longer, entered the sleeping tree later, and spent more time engaged in singing, playing, and grooming behaviors during the mast fruiting period. Playing and grooming are intra-group social interactions. Gibbon songs were sung antiphonally within and among groups, indicating that singing is both an intra- and inter-group social interaction. Furthermore, copulatory behaviors that occurred during female pregnancy were observed during the mast fruiting period, suggesting this might be a social interaction behavior rather than a reproductive activity. Our results show that gibbons extended their daily activity schedules during the mast fruiting period and spent this extra time on social interactions. We examined whether male song complexity increased during the mast fruiting period by using the Levenshtein distance method, but we did not find such a trend. In the mast fruiting period, gibbons may consume more energy than in the non-mast fruiting period. Social and calling behaviors are energetically costly. Our results show that there is a link between energy intake and social and calling behaviors. [ABSTRACT FROM AUTHOR]

Black pepper (Piper nigrum L.) is one of the most popular and oldest spices in the world with culinary uses and various pharmacological properties. In order to satisfy the growing worldwide demand for black pepper, improved productivity of pepper is highly desirable. A primary constraint in black pepper production is the non-synchronous nature of flower development and non-uniform fruit ripening within a spike. The uneven ripening of pepper berries results in a high labour requirement for selective harvesting contributes to low productivity and affects the quality of the pepper products. In Malaysia, there are a few recommended varieties for black pepper planting, each having some limitations in addition to the useful characteristics. Therefore, a comparative study of different black pepper varieties will provide a better understanding of the mechanisms regulates fruit development and ripening. Plant hormones are known to influence the fruit development process and their roles in black pepper flower and fruit development were inferred based on the probe-based gene expression analysis and the quantification of the multiple plant hormones using high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC–MS/MS). In this study, jasmonic acid and salicylic acid were found to play roles in flowering and fruit setting, whereas auxin, gibberellin and cytokinins are important for fruit growth. Abscisic acid has positive role in fruit maturation and ripening in the development process. Distinct pattern of plant hormones related gene expression profiles with the hormones accumulation profiles suggested a complex network of regulation is involved in the signaling process and crosstalk between plant hormones was another layer of regulation in the black pepper fruit development mechanisms. The current study provides clues to help in elucidating the timing of the action of each specific plant hormone during fruit development and ripening which could be applied to enhance our ability to control the ripening process, leading to improving procedures for the production and post-harvest handling of pepper fruits. [ABSTRACT FROM AUTHOR]

Introduction: Pineapple harvesting work contributes to the reporting of musculoskeletal symptoms (MSS) and ergonomic risks. Pineapples are harvested manually in some parts of Malaysia using rattan baskets and workers are exposed to excessive bending, pain and discomfort. This intervention study developed and tested a prototype of an ergonomic harvesting basket to potentially reduce discomfort and physiological workload during a simulation of harvesting activity. Methods: The development and testing of improved harvesting basket was performed in laboratory and workshop. The improved basket had adjustable cushion straps, foam back pad and an opening for unloading of fruits. Harvesting was simulated using improved and existing basket by human subjects and questionnaires were used to assess discomfort. Physiological workload was assessed by heart rate and energy expenditure. Results: A total of 12 male respondents with average age of 22.4 (2.2) years participated in harvesting simulation. Discomfort as measured in Likert scale (mean (standard deviation) for improved basket 4.13 (6.1) vs existing basket 12.26 (11.2); p<0.05) was significantly reduced. Average heart rate (94.13 beats/min vs 89.05 beats/min) and energy expenditure (6 kJ/min vs 5 kJ/min) improved. Conclusion: The use of improved basket was linked to reduction of discomfort and overall workload. Improving design of agricultural manual tools may be able to improve health of workers and prevent MSS. Future fabrication of the improved basket using lightweight materials has potential to be expanded into plantation sectors not limited to pineapples in Malaysia and across Asia. [ABSTRACT FROM AUTHOR]

This paper describes the flowering behaviour of Jatropha curcas cultivated under Malaysian tropical climate. Investigation was carried out by observing the floral morphology, flowering sequence of pistillates, floral anthesis time, flower daily anthesis, flowering and fruiting plant behaviour, flower sex and fruit set ratio. Floral reproductive organs were examined using Scanning Electron Microscope (SEM). Jatropha is monoecious and it produces individual flowers in a dichasial cyme. Each Jatropha inflorescence has at least six compound cymes. The male flower anthesis started the earliest at 12.00 am and once again at 6.10 am to 6.46 am. The female flower anthesis commenced at 6.35 am to 8.25 am. The male flowers opened for a period of 8 to 11 days, while the female flowers opened for only 3 to 4 days. The reading of the male to the female flower ratio was taken twice, 22:1 in December 2008 and 27:1 in April 2009. The flower to fruit ratios were 6:5 (January 2009) and 2:1 (May 2009). Numerically, 0-10 female flowers and 25-215 male flowers are produced in the same inflorescence. In this study, the terminal stem of Jatropha bore fruits profusely in January, May and August 2009. Meanwhile, the development of the floral meristem consists of three stages which include a vegetative stage, a transition from vegetative to floral stage and development of flower parts. The meristem was in the transition stage at day 6. Although all sepals and a petal were developed at day 18, the presence of reproductive organs developing at this particular stage was not detected. Flower and fruit development took approximately 3 months to complete the full cycle, i.e. from the initiated floral bud stage until fruit maturity. [ABSTRACT FROM AUTHOR]

We examined fruiting behaviors of 24 dipterocarp species in a lowland rain forest of Peninsular Malaysia during two consecutive episodes of general flowering (GF). The first GF episode (GF2001) occurred from August 2001 to February 2002, and the second GF episode (GF2002) followed immediately, from March to September 2002. The magnitude of GF2002 was greater than that of GF2001 at the community level. Significant positive size dependence of fruiting behavior at the community level was found in both GF2001 and GF2002, but there was no significant association between the fruiting behaviors in GF2001 and GF2002 except for one species. These results imply that tree size was one of the explanatory factors for fruiting behavior of dipterocarp species, but there was no evidence that adjacent reproduction caused the absence of reproduction and decreased fecundity in the subsequent fruiting event. In contrast, strong spatial aggregation of fruiting trees was found in GF2001, suggesting that external factors may affect fruiting behavior of dipterocarps in a minor GF episode. Among the 12 study species, there were large variations in fruiting behavior, but growth type (e.g., fast-growing or slow-growing) did not simply explain the inter-specific pattern of fruiting behavior. Thus, tree size may account for fruiting behavior of dipterocarps during the consecutive GF episodes through species-specific differences in phonological responses to internal and external conditions. [ABSTRACT FROM AUTHOR]

We observed the diet and activity of Bornean orangutans (Pongo pygmaeus morio) in the primary lowland dipterocarp forests of Danum Valley, Sabah, Malaysia, during 2005–2007, including two mast fruitings. We collected 1,785 hr of focal data on 26 orangutans. We identified 1,466 samples of their food plants and conducted a fallen fruit census to monitor fruit availability in the study area. Their activity budget was 47.2% feeding, 34.4% resting, and 16.9% traveling. Fruits accounted for the largest part (60.9%) of feeding time, especially during mast fruiting periods (64.0–100%), although the percentages of leaves (22.2%) and bark (12.3%) were higher than those reported for P. abelii and P. pygmaeus wurmbii. Although 119 genera and 160 plant species were consumed by focal animals, only 9 genera accounted for more than 3% of feeding time (total: 67.8% for 9 genera). In particular, the focal orangutans fed intensively on Ficus and Spatholobus during most of the study period, especially in periods of fruit shortage. The percentage of fruit feeding changed markedly from 11.7 to 100% across different months of the year, and was positively correlated with the amount of fallen fruit. When fruit feeding and availability decreased, orangutans fed primarily on leaves of Spatholobus and Ficus, and the bark of Spatholobus and dipterocarp. The percentage of time devoted to feeding during mast fruitings, when the orangutans foraged almost exclusively on fruits, was lower than during seasons when the orangutan diet included leaves and bark as well as fruits. Resting increased as feeding decreased in the late stage of each fruiting season, suggesting that the orangutans adopted an energy-minimizing strategy to survive the periods of fruit shortage by using energy stored during the fruit season. Am. J. Primatol. 72:820–840, 2010. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The effects of temperature and light integral on fruit growth and development of five cacao genotypes (Amelonado, AMAZ 15/15, SCA 6, SPEC 54/1 and UF 676) were studied in semi-controlled environment glasshouses in which the thermal regimes of cacao-growing regions of Brazil, Ghana and Malaysia were simulated. Fruit losses because of physiological wilt (cherelle wilt) were greater at higher temperatures and also differed significantly between genotypes, reflecting genetic differences in competition for assimilates between vegetative and reproductive components. Short-term measurements of fruit growth indicated faster growth rates at higher temperatures. In addition, a significant negative linear relationship between temperature and development time was observed. There was an effect of genotype on this relationship, such that time to fruit maturation at a given temperature was greatest for the clone UF 676 and least for AMAZ 15/15. Analysis of base temperatures, derived from these relationships indicated genetic variability in sensitivity of cacao fruit growth to temperature (base temperatures ranged from 7.5°C for Amelonado and AMAZ 15/15 to 12.9 for SPEC 54/1). Final fruit size was a positive function of bean number for all genotypes and a positive function of light integral for Amelonado in the Malaysia simulated environment (where the temperature was almost constant). In simulated environments where temperature was the main variable (Brazil and Ghana) increases in temperature resulted in a significant decrease in final pod size for one genotype (Amelonado) in Brazil and for two genotypes (SPEC 54/1 and UF 676) in Ghana. It was hypothesised that pod growth duration (mediated by temperature), assimilation and bean number are all determinants of final pod size but that under specific conditions one of these factors may override the others. There was variability between genotypes in the response of bean size and bean lipid content to temperature. Negative relationships between temperature and bean size were found for Amelonado and UF 676. Lipid concentration was a curvilinear function of temperature for Amelonado and UF 676, with optimal temperatures of 23°C and 24°C, respectively. The variability observed here of different cacao genotypes to temperature highlights the need and opportunities for appropriate matching of planting material with local environments. [ABSTRACT FROM AUTHOR]

Makes observations on the fruiting characteristics of bird-dispersed Ficus trees in a lowland forest in Malaysia. Asynchronous fruiting morphology; Seasonality of fruiting patterns; Duration of fruiting intervals; Crop size.

• Jackfruit cv. Tekam Yellow has nine stages of growth and took about 107 ± 19 days to complete its growth cycles. • Fundamental knowledge on the growth and development could be used in other scientific works on jackfruit. • Knowledge of cellular structure changes during syncarp development can be particularly helpful growers to apply proper cultivation practices. Jackfruit (Artocarpus heterophyllus Lam.) that belongs to the family Moraceae is an important fruit crop in Malaysia. The planting acreage of jackfruit especially cv. Tekam Yellow has increased by 17.08 % from 2014 until 2018. Jackfruit is highly nutritional with rich phytochemical composition where the flesh and seeds are used as a cooling tonic and as a remedy for overcoming the influence of alcohol in the body. The dietary fibres in jackfruit protect the colon mucous membrane by binding to and eliminating cancer causing chemicals from the colon. Despite the importance of jackfruit to human dietary, little is known about the growth and structural changes during the inflorescence and syncarp development of jackfruit. The study was conducted at a jackfruit commercial farm in Bukit Beruntung (latitude 3°25′32.7432 N; longitude 101°33′21.0240 E), Selangor, Malaysia from January to December 2017. A total of 120 inflorescences and 64 syncarps were used in this study with a randomized complete block design. The earliest phase of the inflorescence involves the development of the ovary and decision to abort or to proceed with further cell division and fruit development, known as syncarp set. In the second phase, the growth of syncarp involves primarily cell division. The third phase begins after cell division ceases. During this phase, syncarp growth continues, mostly by cell expansion, until the syncarp reaches its final size. This growth phase is more prominent and physiologically most significant because of the strong sink activity exerted by the expanding cells. Each stage of syncarp development is marked differently by its cellular activities. A comprehensive study on the phenology growth stage of jackfruit has been published by Kishore (2018). However, the study on growth stage and changes in the cellular structure of jackfruit has yet to be published. Therefore, the aim of this study was to determine growth stages and structural changes in the inflorescence and syncarp development of jackfruit cv. Tekam Yellow. Knowledge of cellular structure changes during the syncarp development is crucial especially for growers to apply proper cultivation practices at different growth stages according to industrial demands for optimum yields and profits. [ABSTRACT FROM AUTHOR]

Masting, the production of large seed crops at intervals of several years, is a reproductive adaptation displayed by many tree species. The predator satiation hypothesis predicts that starvation of seed predators between mast years and satiation during mast years decreases seed predation and thus enhances tree regeneration. Mast fruiting comes at demographic costs such as missed reproduction opportunities and increased density-dependence of recruits, but it remains unknown if predator satiation constitutes a sufficiently large benefit for masting to evolve as a viable life-history strategy. So far, no studies have quantified the net fitness consequences of masting. Using a long-term demographic data set of the dipterocarp Shorea leprosula in a Malaysian forest, we constructed stochastic matrix population models and performed a demographic cost-benefit analysis. For observed values of mast frequency and seed predation rates, we show that strict masting strongly increases fitness compared with fruiting annually. Model results also show that the demographic costs of mast fruiting are very low compared to the demographic losses due to seed predation in a scenario of annual fruiting. Finally, we find that mast fruiting would still be selected for even at low levels of seed predation and when including additional costs such as decreased adult growth rates, limiting crop size and density-dependent seedling survival. Synthesis. Our results are consistent with the predictions of the predator satiation hypothesis: mast fruiting increases fitness for a range of seed predation levels. Under seed predation pressure annually fruiting species are at a strong disadvantage and as a result a mast fruiting strategy may swiftly confer a fitness advantage. Our study shows that demographic modelling allows the weighing of fitness benefits and costs of life-history phenomena such as strict masting. [ABSTRACT FROM AUTHOR]