Optional tool use: The case of wild bearded capuchins (Sapajus libidinosus) cracking cashew nuts by biting or by using percussors

Tool use in humans can be optional, that is, the same person can use different tools or no tool to achieve a given goal. Strategies to reach the same goal may differ across individuals and cultures and at the intra‐individual level. This is the first experimental study at the intra‐individual level on the optional use of a tool in wild nonhuman primates. We investigated optional tool use by wild bearded capuchins (Sapajus libidinosus) of Fazenda Boa Vista (FBV; Piauí, Brazil). These monkeys habitually succeed in cracking open the mesocarp of dry cashew nuts (Anacardium spp.) by pounding them with stones and/or by biting. We assessed whether availability of a stone and resistance of the nut affected capuchins' choice to pound or to bite the nuts and their rates of success. Sixteen capuchins (1–16 years) received small and large dry cashew nuts by an anvil together with a stone (Stone condition) or without a stone (No‐Stone condition). In the Stone conditions, subjects used it to crack the nut in 89.1% (large nuts) and 90.1% (small nut) of the trials. Nut size significantly affected the number of strikes used to open it. Availability of the stone significantly increased the average percent of success. In the No‐Stone conditions, monkeys searched for and used other percussors to crack the nuts in 54% of trials. In all conditions, age affects percentage of success and number of strikes to reach success. We argue that exclusive use of stones in other sites may be due to the higher abundance of stones at these sites compared with FBV. Since capuchins opened cashews with a tool 1–2 years earlier than they succeed at cracking more resistant palm nuts, we suggest that success at opening cashew nuts with percussors may support the monkeys' persistent efforts to crack palm nuts.     

Distribution of Fusarium wilt of Bambara nut (Vigna subterranea (L.) Verdc.) in farmers’ fields’ of Busia County in Western Kenya and its management using farmyard manure

A study was carried out to determine Fusarium wilt distribution in Bambara nut farmers’ fields and its management using farm yard manure (FYM). Four villages in Busia County were purposively sampled for the study. The data generated were subjected to analysis of variance and treatment means separated by least significant difference test. Fusarium wilt incidence in the fields ranged from 14.63 to 43.56%. In the greenhouse, FYM reduced the disease incidence by 10.2% and severity by 9.5% on the black landrace and 1.9 and 12.8%, respectively, on the red landrace. In the field, FYM reduced disease incidence by 9.1% and severity by 6.9% on the black landrace and 10.4 and 10.4%, respectively, on the red landrace. Farm yard manure had the lowest area under disease progress curve irrespective of the landrace. The study confirmed the presence of the pathogen in the fields and the ability to manage the disease using FYM.     

Enrichment of pinolenic acid from pine nut oil via lipase-catalyzed ethanolysis with an immobilized Candida antarctica lipase

Abstract

Pinolenic acid (PLA) enrichment as an ethyl ester from pine nut oil was successfully accomplished in a batch reactor by lipase-catalyzed ethanolysis using Novozym 435 lipase from Candida antarctica as a biocatalyst. PLA is predominantly an sn-3 substituent of the pine nut oil triacylglycerol (TAG), where it accounts for about 39 mol% of the fatty acids esterified at that position. In the presence of ethanol, Novozym 435 exhibited sn-3 regiospecificity with respect to the TAG of pine nut oil. The effect of the molar ratio of reactants on PLA enrichment by ethanolysis was investigated. The molar ratios of pine nut oil to ethanol were varied from 1:20 to 1:100. A fatty acid ethyl ester (FAEE) fraction with higher PLA content was obtained in the early stage of the reaction, although the yield of PLA was small. However, the PLA content of the FAEEs decreased with increasing reaction time, while the yield of PLA increased. The molar ratio of pine nut oil to ethanol that produced the optimum content and yield of PLA in FAEEs was 1:80.     

Predicting walnut (Juglans spp.) crop yield using meteorological and airborne pollen data

Crop yield determines economy by influencing prices on the trade market, and so accurate forecasts of the yield are important for planning various aspects of agricultural production. The main aim of this study is to construct a model for predicting walnut yield in an important walnut production area (the region of Novi Sad in Northern Serbia). Relationships between the amount of walnuts produced annually (2000–2011) and abiotic (e.g. meteorological) and biotic (e.g. airborne pollen data) factors were examined using Pearson correlation analysis. Walnut yield data were then entered into linear regression models with variables that had the highest correlations. The models were constructed using 10 years of data, and tested using 2 years of data not included in constructing the model. This paper has shown that walnut yield is greatly dependent on weather conditions, particularly during fertilisation and seed growth, but the amount of available airborne pollen also plays an important role. The introduction of the seasonal pollen index, as a proxy for the amount of pollen available for fertilisation, improved the performance of models predicting walnut yield.     

Integrated genome sequence and linkage map of physic nut (Jatropha curcas L.), a biodiesel plant

The family Euphorbiaceae includes some of the most efficient biomass accumulators. Whole genome sequencing and the development of genetic maps of these species are important components in molecular breeding and genetic improvement. Here we report the draft genome of physic nut (Jatropha curcas L.), a biodiesel plant. The assembled genome has a total length of 320.5 Mbp and contains 27 172 putative protein‐coding genes. We established a linkage map containing 1208 markers and anchored the genome assembly (81.7%) to this map to produce 11 pseudochromosomes. After gene family clustering, 15 268 families were identified, of which 13 887 existed in the castor bean genome. Analysis of the genome highlighted specific expansion and contraction of a number of gene families during the evolution of this species, including the ribosome‐inactivating proteins and oil biosynthesis pathway enzymes. The genomic sequence and linkage map provide a valuable resource not only for fundamental and applied research on physic nut but also for evolutionary and comparative genomics analysis, particularly in the Euphorbiaceae.     

Arecoline and the 30–100 kDa fraction of areca nut extract differentially regulate mTOR and respectively induce apoptosis and autophagy: a pilot study

Areca nut (AN) is recognized as a human carcinogen; however, few studies of the cytotoxic effects of AN ingredients on cells have been reported. In Taiwan, AN, lime and inflorescence of Piper betle are the common components of betel quid (BQ). We recently noticed that extract of AN (ANE), but not those of lime and inflorescence of Piper betle, induces rounding cell morphology and nuclear shrinkage in different types of carcinoma cells. In this study, the rounding cell activity was first traced to the partially purified ≥10 kDa fraction (ANE ≥ 10 K) and subsequently to the 30–100 kDa fraction (ANE 30–100 K). ANE and ANE ≥10 K stimulated nuclear shrinkage (P < 0.001 in both cases) and the clearance of the cytoplasm. ANE, ANE ≥ 10 K, and ANE 30–100 K induced the cleavage of LC3-I (P < 0.05, 0.01, and 0.05, respectively) and the emergence of autophagic vacuoles (AVs) and acidic vesicles. On the other hand, arecoline (Are, the major alkaloid of AN) triggered caspase-3 activation, peri-nuclear chromatin condensation, and micronucleation. Meanwhile, ANE 30–100 K, but not Are, inhibited the phosphorylation of the mammalian target of rapamycin (mTOR)-Ser²⁴⁴⁸. In conclusion, this study demonstrates that different AN ingredients exerting differential impact on mTOR-Ser²⁴⁴⁸ phosphorylation are capable of triggering apoptosis and autophagy. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Shyun-Yeu Liu, Mei-Huei Lin, Yu-Rung Hsu and Ya-Yun Shih contributed equally to this work.     

A historical review of research on the weaver ant Oecophylla in biological control

1 Although the weaver ant Oecophylla is the first written record of biological control, dating from 304 ad , there have been fewer than 70 scientific publications on this predator as a biological control agent in Asia, from the early 1970s onwards, and fewer than 25 in Africa. 2 Apart from crop‐specific ecological and perceptual factors, a historical review shows that political and market forces have also determined the extent to which Oecophylla was incorporated into research and development programmes. 3 In Africa, research on weaver ants in biological control concentrated on export crops, such as coconut and cocoa, whereas, in Asia and Australia, research focused on fruit and nut crops, primarily destined for domestic markets. 4 Increased evidence of pesticide inefficiency under tropical smallholder conditions, changing paradigm shifts in participatory research and a growing scientific interest in local knowledge in the early 1990s opened up new avenues for research on conservation biological control. 5 Lobbying and advocacy have been needed to ensure that Oecophylla was recognized as an effective biological control agent. 6 With an increased market demand for organic produce, holistic approaches such as conservation biological control, particularly the use of Oecophylla, are increasing in importance. 7 Multi‐stakeholder strategies for collaborative learning are proposed for a better control of major fruit, nut and timber tree pests in Africa, Asia and Australia.