Intellectual property in entomology: Analysis and perspective on recent trends in global patent publications

Intellectual property (IP) is an important consideration for entomological research and provides a means to capture value from new discoveries. Herein, we describe an analysis of more than 26 000 patent publications from 2007–2017 related to the field of entomology. These patents were divided among 8000 patent assignees; however, only 5% of the assignees had ≥10 patents. Corporations accounted for the largest share of patents (59%), with individuals (20%), academic institutions (17%) and government organizations (4%) making up the remaining segments. From 2007–2017 the number of entomological patents increased by 400%, with the largest number being from China. However, unlike patents from Europe, Japan or the US, which target a range of countries, the Chinese patents almost exclusively focus on China. Among the array of subjects covered are transgenic insects and plants, repellents, recombinant insect cells, with the highest proportion of patents focused on insecticides (39%), followed by insecticide mixtures (27%) and formulations (21%). The top 30 patent assignees included companies/institutions from China (18), Europe (3), Japan (6) and the US (3). Among the top 12 entities, IP from the US assignees was distributed across insecticides, mixtures and insecticidal traits while those from China were more focused on mixtures. However, given expanding IP numbers from China it is expected that in the future there will be a greater impact on new insecticides and related technologies. © 2020 Society of Chemical Industry     

Interference Effects in Grass Varieties Grown as Pure Stand, Complex Mixture and Binary Mixture with White Clover

The study aimed at: i) assessing the agronomic value of the pure stand (PS), of the complex mixture (CM) and of the binary mixture with each of six white clover genotypes (MWC) of eight grass varieties belonging to four species and contrasting for earliness of flowering; and ii) investigating the relationships of competitive abilities in CM and MWC with some morpho-physiological traits of the grass varieties. CM showed a 24 % dry matter yield (DMY) advantage over mean value of PS but did not outyield the pure stand of the best yielding component. For grass-white clover associations, the DMY advantage as Relative Yield Total over PS of the components averaged 43 %. DMY of the grass varieties averaged across MWC conditions was related positively to total DMY (r = 0.99) and negatively to associated clover DMY (r = - 0.96). Competitive abilities as Relative Yield of the grass varieties in CM and in MWC correlated (r = 0.84) and were both positively associated to DMY, canopy height and inclination of leaves in PS. The results suggested that association of white clover with a grass of moderately high vigour, intermediate earliness and relatively erect leaves may provide the best option for rotational meadows in the experiment environment.     

Yielding Ability of Pure Stands and Equal Proportion Blends of Rapeseed (Brassica napus L.) with Double-low Quality

Yielding ability of intraspecific mixtures is an important issue not only for homozygous and homogeneous crops but also for heterozygous and/or heterogeneous ones. The goal of the present study was to examine the performance of mixtures and synthetics from double-low (low in erucic acid and glucosinolates) rapeseed ( Brassica napus L.) as compared to pure stands. The material consisted of seven lines and from 1982/83 to 1984/ 85 lines, all possible biblends and syn₁'s (1983/84 and 1984/85 exclusively) were grown in a completely randomized block design. An analysis of variance was conducted and general mixing effects (g.m.e.) and specific mixing effects (s.m.e.) were calculated for components of biblends. A few pure-standing lines yielded higher than some mixtures. Nevertheless, the overall mean of mixtures was not exceeded by any pure stand. For selection purposes, the higher variance of 'among lines' in comparison with 'among blends' would not result in higher yields because of the generally higher yielding ability of blends. Additionally, mixtures were marked by higher yield stability as compared to pure-standing lines. On the average of two years of testing yields of syn₁'s amounted higher than yields of mixtures. Differences between 'g.m.e.' of lines were proved and moreover, the variance component of 's.m.e.' was on a lower level than that of 'g.m.e.'. Consequently, in order to find the best mixture it seemed not necessary to analyse a complete diallel rather than to apply factorial or incomplete factorial concepts.     

Beyond redundant kill: A fundamental explanation of how insecticide mixtures work for resistance management

The use of insecticide mixtures for resistance management has been a controversial topic for many decades. Here, we provide a reassessment of the fundamental theory of insecticide mixtures. First, we examine how mixtures differ from other strategies. We suggest that the fundamental strategy concept of a mixture is defined by the simultaneous use of insecticides and their overlapping exposure. Second, we provide a simple, illustrative model to show how mixtures affect resistance evolution. Following the existing literature, we identify a role for ‘redundant kill’ acting against resistant individuals, which we link to the overlapping exposure of insecticides. We also identify the occurrence of ‘additional kill’ acting against susceptible individuals, which is the immediate consequence of the simultaneous use of insecticides. Third, we take a basic approach to the comparison of mixtures and other strategies using a simple model. We find that a common comparison of the time to resistance alone leaves the effects of additional kill unaccounted for. Moreover, we demonstrate that different approaches to comparison can lead to different results because of biases that are introduced in the comparison setup. Fourth, still using the same model, we showcase a more sophisticated approach to comparison using optimised strategies. We find that optimised mixtures always perform better than other strategies due to the combination of redundant and additional kill. We suggest that the comparison of optimised strategies is unbiased because each strategy is performing the best that it can. On this basis, in theory (but not necessarily practice), we believe that mixtures are better than other strategies and, through the steps of our argument, we can tie this success back to the fundamental properties (of simultaneous use and overlapping exposure) that distinguish mixtures from other strategy concepts. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Protein,energy and mineral utilization in rats fed rice-legume diets

Protein, energy and mineral utilization were examined in growing rats fed cooked, dry legume seeds in combination with polished rice. The legumes tested included 3 varieties of common beans, black, white and brown (Phaseolus vulgaris), lentils (Lens esculenta) and peas (Pisum sativum). The rice:legume mixtures (1:1 N ratio) were the only dietary sources of protein, Zn, Fe and Cu. The rice:black bean mixture was also tested at a 4:1 N ratio. Nutrient utilization was studied by balance trials and mineral utilization was further assessed by tissue analyses. True protein digestibility (TD) and energy digestibility of the rice:legume (1:1) mixtures were high. Biological value (BV) varied only little but was lowest in the rice:lentil mixture. The rice:brown bean mixture had the lowest amount of utilizable protein (UP). The (1:1) rice:legume mixtures did not adversely affect Fe status, as measured by liver Fe content and blood hemoglobin and hematocrit, or Cu status, as measured by liver Cu content and plasma ceruloplasmin. However, femur zinc content indicated a sub-optimal Zn status. Increasing the dietary N from rice in combination with black beans resulted in a substantial improvement of BV, NPU and Zn status of the animals but had a negative effect on UP and Fe status of the rats.     

Columns and Detectors Recommended in Gas Chromatography to Measure Greenhouse Emission and O2 Uptake in Soil: A Review

ABSTRACT

Gas chromatography (GC) is a technique used to analyze substances/molecules (as chemical species) with a system composed of chromatograph, column, and detector. This study has the objective of reviewing the use of GC in monitoring greenhouse gases (GHG; carbon dioxide: CO₂; methane: CH₄; nitrous oxide: N₂O) emission and O₂ (oxygen) uptake in soil, demonstrating results from experiments around the world and alternative use of sensors to monitor these gases in soil. Our study shows that the correct column and detector depend on analyzing gas and the advantages and disadvantages of the column and the detector. The columns, packed and capillary, have been more used and are considered better options to analyze GHG emission and O₂ uptake in soil science. Thermal conductivity detector (TCD), electron capture detector (ECD) and mass selective (MS) are great choice to monitor CO₂ emission; flame ionization detector (FID) equipped with methanizer allows the detection of CO₂ and CH₄ emission; and ECD detects the amount of N₂O emitted. Moreover, both, TCD and ECD, also can be used to detect O₂ uptake. GC system is complex, and to identify of GHG emission and O₂ uptake is necessary the use of column (packed or capillary) and may contain multiple detectors, i.e. three (TCD, ECD, and FID) or two detectors (FID and ECD). Field and laboratory study should be run to verify the efficacy of sensors to monitor GHG emission and O₂ uptake as an alternative of GC system.     

Do invertebrate decomposers affect the disappearance rate of litter mixtures?

We designed an experiment using litter bags with fine and coarse mesh size to analyse interacting effects between invertebrate decomposers and the number of litter species on litter disappearance rates. We used litter of nine broad-leaved tree species to compare disappearance rates of litter from single species with mixtures of two to six species. Species composition of litter and invertebrates interacted strongly in their effects on litter disappearance rate. Contribution of invertebrates to litter disappearance increased with time mainly for litter which disappeared slower in the absence of invertebrates. Disappearance rates were positively correlated with initial N content and negatively correlated to initial C content of litter. These relationships were stronger in the presence of invertebrates, suggesting that their activity is positively related to initial litter chemistry. Number of component litter species, however, had no effect on disappearance rate irrespective of the activity of invertebrates. Using individual rates of disappearance for single species, we calculated the expected rates of disappearance for each of the experimental mixtures of leaf litters. We found that mixtures of several species of leaf litter resulted in significant deviations from the expected values. These deviations showed a significant effect of the number of component litter species. However, this result was caused by a strong negative deviation of one single mixture of six species. The presence of invertebrates resulted in even greater deviations from the expected values, suggesting an important contribution of invertebrates to the effects of litter mixing on litter disappearance rates. Hence, our results underline the importance of idiosyncratic effects of species traits in mixtures. Our results suggest that the influence of invertebrate decomposers interacts with litter chemistry during decomposition, but is not affected by litter species richness per se.     

Plant growth and nitrogen concentration of Tillandsia species produced in organic,volcanic, and lignocellulosic substrates

We analyzed the effect of substrate mixtures containing vermicompost (VC), tezontle (TZ), and pine bark (PB) in the following percentage proportions (v/v): T1: 00VC-20TZ-80PB; T2: 10VC-20TZ-70PB; T3: 20VC-20TZ-60PB; T4: 30VC-20TZ-50PB, plus two reference controls identified as T5: peat-moss (100%; PM) and T6: tree branch (TB) on growth and nitrogen concentration of Tillandsia flavobracteata and T. limbata. Tillandsia flavobracteata displayed the greatest height in T6 and T4, while the greatest height for T. limbata was obtained in T3. In T. flavobracteata the greatest number of leaves was obtained in T1, whereas in T. limbata no significant differences were found. Nitrogen was higher in T. limbata, especially when grown in T1 and T6. We were able to demonstrate that both Tillandsia species can grow and produce healthy plants under our experimental conditions, while the tested substrates differentially affected growth and nitrogen concentration in each species.     

Robustness in the mineral supply from temporary grasslands

Abstract

The current study examined the capacity of different temporary grassland legume–grass mixtures under different N supply levels to supply similar amounts of elements in systems where the herbage is cut for feed. Mixtures showed a good robustness in supplying equal amounts of mineral elements in the combined herbage as well as equal concentrations in dry matter of mineral elements compared with the same species in monocultures. The reasons for the mixed systems to be able to buffer differences in N supply levels as well as different compositions of the mixtures were that legume leaves and stems had similar concentrations of mineral elements, whether in monocultures or in mixtures with grasses. Grasses in mixture with legumes had however higher N, Ca, S, Zn, Cu and tended to have higher Mg concentration, both in stems and leaves, while Mn were less concentrated in mixtures’ dry matter. Further, the mixtures doubled their dry matter accumulation in the two weeks just around grass heading. The systems partly buffered the time-wise differences in the sense that the P accumulation paralleled dry matter but the N was diluted. This was mirrored in a decrease in N concentration and maintenance of the concentration level of P and other elements. As the stem–leaf ratio was higher (p<0.05) in festulolium than in ryegrass and as the stems of festulolium have lower concentrations of N, K, Ca, S, Mg, Fe and Cu than leaves, the mixtures including festulolium had a rapidly declining proportion of these elements in the combined mixtures’ dry matter. Management options in improving the mineral supplies are thus to choose species when establishing the temporary grasslands according to functionality, to manipulate the content of legumes by the N supply level, and to time the harvest of the herbage.     

Nitrogen fixation of annual temperate clover species determined by the nitrogen difference method

The nitrogen fixation ability of Trifolium vesiculosum cv. Amclo and Trifolium subterraneum cv. Mount Barker in pure and mixed stands with Lolium multiflorum cv. Midmar were compared using the nitrogen difference method (NDM). The percentage and quantity of apparent legume‐derived nitrogen, as affected by different nitrogen applications and grass seeding rates, was estimated. The response of both clover species varied with treatments in pure and mixed stands. The apparent legume‐derived nitrogen ranged from 15–98% and from 43–94%, while quantities ranged from 20–102 kg ha^?1 and from 68–260 kg ha^?1 for T. vesiculosum and T. subterraneum, respectively. Results indicate that the uptake of available soil nitrogen contributed to the total nitrogen content of both clover species. However, since the application of the NDM is limited, conclusions as to the response differences and the possible transfer of nitrogen to the grass component could be unreliable.