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1.
Western Friuli, Italy, there is a small area near the town of Pordenone where an ancient rite of spring is still carried out. This is the preparation of a special dish, known as “pistic,” a collection of 56wild herbaceous meadow and wood plants which are boiled and then sautéed together. This practice is still alive in a few areas of Friuli today and possibly goes back to pre-Roman Celtic cultures in this part of Friuli. The number of herbaceous plants used in this dish is extraordinarily high (56), especially when compared to the low number normally used in other conventional dishes. “Pistic” is therefore important, not only because it represents a quantitatively high use of wild herbs in the diet of the rural population, but also because it reflects environmental awareness, in that the archaic method of naming, identifying and using these plants still exists today. Similar rural practices include the use of “pot herbs” in Great Britain and in France the cooking of “mesclun.”  相似文献   

2.
The pesticide efficacy of locally available seven botanicals “Gime” (Chenopodium ambrosioides), “Ayderke” (Jatropha curcas), Neem (Azadirachta indica), Melia (Melia azadirach), “Chobe” (Cisus rotonifolia), “Kelewa” (Maesa lanceolata) and “Antharfa” at a rate of 4% weight by weight was evaluated for the control of cowpea bruchid using 200?g cowpea seeds in 500?cm3 volume jar in 2010 and 2011 under laboratory condition at Sirinka Agricultural Research Centre. The combined analysis showed that “Gime” (both leaf and seed) had high speed of pesticide effect as it showed significantly higher per cent of parent adult mortality (84 and 71%, respectively) as to the standard check Malathion 5% dust (100%) in the first day of adult mortality count. “Antharfa” and “Ayderke” also have shown significantly higher per cent of parent adult mortality as to Malathion in the third and fifth day of adult mortality count, respectively. In the seventh day, all botanicals showed significantly higher per cent of adult mortality as compared to untreated check. “Gime” leaf and seed powder, “Ayderke” seed, Neem seed and “Antharfa” leaf powders significantly reduced the number of progeny emergence per day as compared to all other treatments. Moreover, these botanicals were effective in reducing per cent seed damage (0.00, 0.00, 0.57, 5.86 and 10.86%, respectively) and storage loss (0.00, 0.00, 0.073, 1.02 and 2.27%, respectively). Gime (both leaf and seed powder), “Ayderke” seed and Neem seed are locally available, simple for preparation and environmentally friendly. Therefore, these three botanicals can be recommended to satisfy the demand for organic food and save the seed damage and yield loss of cowpea caused by Callosobruchus maculates and bean bruchid (Zabrotes subfasciatus) which has similar biology with Callosobruchus maculatus.  相似文献   

3.
Achieving food sufficiency in a sustainable manner is a major challenge for farmers, agro-industries, researchers and governments. Amongst agricultural pests supressing crops, root-knot nematodes (Meloidogyne spp.) represent possibly the world’s most damaging one, the control of which has been mainly based on chemical nematicides. In the recent years the environmental, food safety and animal welfare issues pose the need for alternative nematode control measures. Screening naturally occurring compounds in plants, involved in the complex chemical-mediated interactions between a plant and other organisms in its environment, can provide with innovative nematode control measures that can be safely used in integrated pest management programs. The Mediterranean Basin is an area where various soils and climatic conditions allow a vast plant biodiversity providing with chemical botanicals of significant nematicidal potency. This is a review on the Mediterranean botanicals that can control Meloidogyne spp.  相似文献   

4.
A formula for computing the mean infection success per miracidium (“infection index”) is given for every permutation of the numbers of snails and miracidia in miracidial exposure experiments. This “infection index” allows the comparison of the results from quantitatively different exposure methods and may be important for characterizing special trematode- intermediate host systems. By means of the “infection index” it is shown that a laboratory population of Lymnaea stagnalis is homogeneous with regard to its susceptibility to Isthmiophora melis miracidia, i.e. that there is no appreciable rate of resistant individuals. Some experimental results which have been published by other authors and have been interpreted by them as indicating the resistance of a portion of snail populations can be numerically explained by means of the formula of the “infection index” and without necessarily assuming resistance.  相似文献   

5.
Legumes, especially acacias, are considered amongst the most successful invaders globally. However there is still very little known about the role of soil microbial communities in their invasion success in novel ranges. We examined the role of the soil microbial community in the invasion success of four Acacia species (A. cyclops, A. longifolia, A. melanoxylon and A. saligna) and a close relative Paraserianthes lophantha, introduced into novel regions within Australia using a “black-box” approach. Seed and soil material were collected from multiple populations within each species’ native and introduced range within Australia and used in a plant-soil feedback experiment to assess the effect of the soil microbial community on plant growth and nodulation. We found no effect, either positive or negative, of soil origin on species’ performance, however there was a significant interaction between species and seed origin. Seed origin had a significant effect on the biomass of two species, A. cyclops and A. saligna. A. cyclops plants from the native range performed better across all soils than plants from the introduced range. The opposite trend was observed for A. saligna, with plants from the introduced range performing better overall than plants from the native range. Seed or soil origin did not have a significant effect on the presence and number of nodules suggesting that rhizobia do not constrain the invasion success of these legumes. Our results suggest that plant-soil feedbacks are unlikely to have played a significant role in the invasion success of these five species introduced into novel regions within Australia. This may be due to the widespread occurrence of acacias and their associated soil microbial communities throughout the Australian continent.  相似文献   

6.
In plants, narrow geographic distributions are generally associated with low colonization and persistence abilities, therefore narrowly distributed plants are expected to have lower plant recruitment success than widespread species. Determining the association between recruitment success and range size requires the comparison of the success in multiple life-history stages among narrowly distributed and widespread congeners sharing the same habitat, an integrated approach rarely considered. We compared transition probabilities from ovule to reproductive adult between the narrowly distributed annual vine Ipomoea rubriflora O’Donnell (Convolvulaceae) and the widespread Ipomoea purpurea (L.) Roth at sites in Chaco woodland where they co-occur. I. rubriflora had marginally lower ovule fertilization success, a lower probability of seed maturation and lower seedling establishment than I. purpurea. The lowest transition probability for both species was seedling emergence. Seedling establishment in I. rubriflora was similar to seedling emergence. Plant recruitment success in I. rubriflora was an order of magnitude lower than that of I. purpurea. Indeed, I. rubriflora had lower total seed production per plant and smaller seed mass. Our results suggest that understanding processes determining regeneration (i.e., seedling emergence and establishment) may be of high importance for understanding narrow distributions in annual plants. The results also suggest that the narrowly distributed species is not only at a “numerical disadvantage” for colonizing new sites—i.e., lower total seed production per plant—but it also has a lower per-seed probability of establishing and thus to persist. However, as lower establishment success in this species seemed to be associated with the lower ability to survive adverse conditions of seedlings from smaller-seeded species, a narrower regeneration niche might also explain its narrow distribution.  相似文献   

7.
Despite the presence of melon‐headed whales in tropical and subtropical waters worldwide, little is known about this species. To assess population structure in Hawai‘i, dedicated field efforts were undertaken from 2000 to 2009. Using only good quality photographs, there were 1,433 unique photo‐identified individuals, of which 1,046 were distinctive. Of these, 31.5% were seen more than once. Resighting data combined with social network analyses showed evidence of two populations—a smaller, resident population, seen exclusively off the northwest region of the island of Hawai‘i, and a larger population, seen throughout all the main Hawaiian Islands (hereafter the “main Hawaiian Islands” population). A Bayesian analysis examining the probability of movements of individuals between populations provided a posterior median dispersal rate of 0.0009/yr (95% CI = 0–0.0041), indicating the populations are likely demographically independent. Depth of encounters with the Hawai‘i Island resident population was significantly shallower (median = 381 m) than those with the main Hawaiian Islands population (median = 1,662 m). Resightings of individuals have occurred up to 22 yr apart for the Hawai‘i Island resident population and up to 13 yr apart for the main Hawaiian Islands population, suggesting long‐term residency to the islands for both populations.  相似文献   

8.
In the early twentieth century, viruses had yet to be defined in a material way. Instead, they were known better by what they were not – not bacteria, not culturable, and not visible with a light microscope. As with the ill-defined “gene” of genetics, viruses were microbes whose nature had not been revealed. Some clarity arrived in 1929 when Francis O. Holmes, a scientist at the Boyce Thompson Institute for Plant Research (Yonkers, NY) reported that Tobacco mosaic virus (TMV) could produce local necrotic lesions on tobacco plants and that these lesions were in proportion to dilutions of the inoculum. Holmes’ method, the local lesion assay, provided the first evidence that viruses were discrete infectious particles, thus setting the stage for physicochemical studies of plant viruses. In a field where there are few eponymous methods or diseases, Holmes’ assay continues to be a useful tool for the study of plant viruses. TMV was a success because the local lesion assay “made the virus visible” and standardized the work of virology towards determining the nature of the virus.  相似文献   

9.
Using surrogate taxa in the monitoring of restoration success is strongly advocated but currently under debate. Are butterfly and vascular plant communities good surrogates for each other in monitoring the restoration of calcareous grassland grassland? The research was conducted in a small area in Tuscany (central Italy), which was the focus of a restoration project. We sampled vascular plants using 35 plots (1 m2) and butterflies using 20 transects (100 m in length) belonging to four treatment types: control scrubland, restored ex-arable, restored grassland and reference grassland. A mixed model nested ANOVA showed that reference grassland, 3 years after restoration, had the highest number of vascular plant species and the highest number of butterfly species. The different treatments were found to be distinct from a compositional point of view: pRDA showed that the “treatment” factor, independent of spatial variables, accounted for 22.1 and 21.9% of the total variance in the plant community and butterfly community, respectively (p < 0.01). The butterfly community was significantly correlated with the entire plant community data set and with the phanerophyte community (i.e. shrubs); larval host plants were significantly correlated with the composition of non-migratory butterflies. The results indicated that butterfly and vascular plant communities were congruent, suggesting the use of community composition of different taxa as a valuable tool for the evaluation of management success.  相似文献   

10.
The nettle caterpillar, Darna pallivitta (Moore) (Lepidoptera: Limacodidae), is an invasive pest on the island of Hawai’i, causing defoliation of ornamental nursery stock and posing a human health hazard due to their urticating hairs that can cause painful stings. Wind tunnel and field tests with 2–3‐day‐old moths revealed behavioral responses of males to caged females, which is indicative of a female‐released sex pheromone. Coupled gas chromatography‐electroantennogram detection (GC‐EAD) analysis of female abdominal tip extracts revealed two male electroantennographically active compounds produced by female D. pallivitta. Mass spectral analysis and subsequent synthesis identified the active compounds as n‐butyl (E)‐7,9‐decadienoate (major component) and ethyl (E)‐7,9‐decadienoate (minor component), both structurally similar to sex pheromone components previously reported from related Darna spp. Additionally, methyl (E)‐7,9‐decadienoate was identified from female abdominal tip extracts and a strong EAD response was elicited by the synthetic compound. n‐Butyl (E)‐7,9‐decadienoate was the only component detected by solid phase microextraction (SPME) collections from single calling female moths, however, the apparent absence of minor components may be a result of their lower abundance. Field trials showed significant attraction of male moths to all lures containing the n‐butyl ester, while the methyl and ethyl esters did not increase trap captures at the levels and ratios tested. Synthetic pheromone lures (2.5 mg) outperformed virgin moths as attractant baits and could be used for monitoring D. pallivitta populations of the island of Hawai’i and detection on other Hawai’ian islands and at ports and nurseries that receive plants from Hawai’i (e.g., California and Florida).  相似文献   

11.
The “Midichloria clade” is a recently discovered but well-established evolutionary lineage clustering inside the order Rickettsiales (Alphaproteobacteria). Not much is known about the biology of these organisms. The best characterized ones are endocellular symbionts of very different eukaryotic hosts, ranging from arthropods to protists. “Candidatus Midichloria mitochondrii”, the most studied organism of the group, is an interesting object of study because of its unique capability to infect metazoans’ mitochondria and the presence of flagellar genes in its genome. With this work, we aim at increasing the knowledge on the biodiversity and phylogeny of the “Midichloria group”. We characterized according to the “full cycle rRNA approach” two novel endosymbionts of ciliated protozoa, i.e. Paramecium nephridiatum and Euplotes aediculatus. According to the nomenclatural rules for uncultivated prokaryotes, we established the novel taxa “Candidatus Defluviella procrastinata” and “Candidatus Cyrtobacter zanobii” for the two bacterial symbionts. Our phylogenetic analysis based on 16S rRNA gene sequences confirms that the evolutionary histories of “Midichloria clade” representatives and of their hosts are very different. This suggests that the symbiotic processes arose many times independently, perhaps through ways of transmission still not described in Rickettsiales.  相似文献   

12.
The “Quan Fang Bei Zu”, a first dictionary for Chinese plants, which contains 27 volumes in its first collection and 31 volumes in its second collection, was completed by Chen Jing-yi in 1253, the First Year of Bao You of Li Zong in Song Dynasty. The first part of this encyclopaedia of plants is devoted to flowers. The second part is of more varied nature, dealing with fruit trees, plants in general, herbs, trees, agriculture and sericulture, vegetables, and medicinal herbs. These two collections cover 267 kinds of plants, each of which is described under two categories separately: The first category, “Si Shi Zu” in Chinese, meaning “facts of the plants” concerned, which again divided into 3 entries, i.e. the history, miscellaneous information and sundry bits of the plants. The second category, “Fu Yong Zu” in Chinese, meaning poetry, which divided into 10 meters, wherein the plants are described and eulogized in poetrical expressions. Later on, the “Quan Fang Bei Zu” was used as a blueprint for some famous books in China, for example, the “Qun Fang Pu” and the “Guang Qun Fang Pu” all written and compiled after its model. It is known today that in China there are only two extant hand writting copies of it, one in Beijing Library, the other in the Library of Yunnan University. Both of them are listed as the best national books. Outside China, it is known that a third copy of is in the Congress Library in U.S.A. As for the original wood-carving copy printed during the period of the Song Dynasty, it is known so far that one copy is kept in the Library of Culture Ministry of Japan. The Beijing Agriculture Publishing House has made a decision to photograph this carved copy in the Culture Ministry of Japan as one of the “Precious Series of China Agriculture Science”. The book plays a very important role in the study of chinese botany, agri-culture science, medicine, history and literature.  相似文献   

13.
This study investigated the use of woody plants by a rural community in an area of dry land Caatinga vegetation in northeastern Brazil. Information was obtained concerning this woody species with a diameter that is equal to or greater than 3 centimeters (cm) at soil level surveyed in 100 sample plots totaling 1 hectare (ha). The following question is the hypothesis we tested. Is a plant’s relative importance (as measured by its use value) related to its “apparency,” as measured by its abundance and ecological dominance? “Apparency” explains the use value of plants in four categories: medicinal, construction, fuel, and technology. The most important uses of woody plants are related to harvesting for energy and construction purposes.  相似文献   

14.
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16.
In most populations of Solidago altissima, a small proportion of plants have a growth pattern in which the stem bends early in the season so that the apex is pointing downward (i.e., a “candy-cane” stem) then straightens up again later in the season. The majority of plants, however, do not show this pattern. Instead their stems remain erect from emergence through flowering and senescence. It has recently been shown that the candy-cane stems are a result of a ducking strategy that reduces the risk of attack by apex-attacking herbivores. With such a resistance advantage, it is unclear why the candy-cane morphology is always in the minority, and why the erect morphology persists at all in S. altissima populations. In this study, we tested the hypothesis that the advantage of ducking is inversely frequency dependent and thus will not be an effective resistance strategy when ducking plants are in the majority. In a series of trials, we introduced gall flies (Eurosta solidaginis) into enclosures with relatively low (15%) and relatively high (85%) frequencies of candy-cane versus erect stems. Candy-cane stems were more resistant than erect stems regardless of relative frequency; thus, the hypothesis was rejected. Overall, attack rates were lower for both stem types in the high candy-cane frequency groups than in the low candy-cane frequency groups. This frequency-dependent attack rate suggests that erect-stemmed plants gain “associational resistance” by having a majority of candy-cane neighbors, while candy-cane plants suffer from “associational susceptibility” when surrounded by erect-stemmed neighbors.  相似文献   

17.
Distinguishing things from beings, or matters from lives, is a fundamental question. Extending E. Schr?dinger's neg-entropy and I. Prigogine's dissipative structure, we propose a chemical kinetic view that the earliest "live" process is embedded essentially in a special interaction between a pair of specific components under a particular, corresponding environmental conditions. The interaction exists as an inter-molecular-force-bond complex(IMFBC) that couples two separate chemical processes: one is the spontaneous formation of the IMFBC driven by a decrease of Gibbs free energy as a dissipative process; while the other is the disassembly of the IMFBC driven thermodynamically by free energy input from the environment. The two chemical processes coupled by the IMFBC originated independently and were considered non-living on Earth, but the IMFBC coupling of the two can be considered as the earliest form of metabolism: the first landmark on the path from things to a being. The dynamic formation and disassembly of the IMFBC, as a composite individual, follows a principle designated as "… structure for energy for structure for energy…", the cycle continues; and for short it will be referred to as "structure for energy cycle". With additional features derived from this starting point, the IMFBC-centered "live" process spontaneously evolved into more complex living organisms with the characteristics currently known.  相似文献   

18.
A number of examples exist of trade-offs between mating success and survival; that is, success in one fitness component comes at the cost of success in the other fitness component. However, these expected trade-offs are – perhaps even more commonly – not observed. One explanation for this apparent paradox of missing trade-offs could be that the other factors generating fitness variation across individuals confound or obscure the expected trade-off. These confounding effects could arise in two general ways: (i) the additional source of variation could positively (or negatively) influence both fitness components (“shared confounder” hypothesis), or (ii) the additional source of variation could influence only one fitness component (“non-shared confounder” hypothesis). We tested whether parasitism by Gyrodactylus spp. could be a confounder of trade-offs between female preference and susceptibility to predation for male Trinidadian guppies (Poecilia reticulata). As in previous work, we did not find the expected trade-off; that is, the males preferred by females were not more likely to be eaten by predators. Because half of the experimental males were infected by Gyrodactylus in a paired design, we were able to show that females discriminated against infected males, but that infected males were not more susceptible to predation. Our results thus provide support for the non-shared confounder hypothesis. That is, by negatively affecting one fitness component (female choice) but not the other (susceptibility to predation), parasitism by Gyrodactylus could obscure the expected trade-off between female preference and susceptibility to predation.  相似文献   

19.
Starch-slab gel electrophoresis showed two patterns of peroxidase isoenzymes in the polymorphic taxon. Xanthium strumarium L. The “strumarium” morphological complex (X. strumarium, in the sense of Millspaugh and Sherff), the putative indigenous plants of the Old World, contained a different pattern from that shown by putative introductions from the New World. Experimental F1 hybrids between “strumarium” and other complexes, “italicum-pennsylvanicum”, “chinense”, “oviforme” and “cavanillesii”, had the peroxidase pattern of the American plants. These peroxidase isoenzyme patterns were not influenced by the environmental growing conditions, but, along with partial genetic incompatibility, support the taxonomic separation of X. strumarium from other taxa of section Euxanthium.  相似文献   

20.
Little is known about the network structure of competition in large populations of plants, despite the importance of such knowledge for understanding population dynamics. In this study, we used complex network analysis to examine temporal changes in the network structure of competition in an even-aged multi-individual stand of the Sakhalin fir Abies sachalinensis in Hokkaido, Japan. Using census data, which were measured over 30 years (1948–1978; seedlings were planted in 1929), on the sizes and locations of these plants, we regarded a plant as a node and competition between plants as a link. We then introduced two indices, the binary and weighted out-degrees (BO and WO, respectively), to interpret complicated plant interactions. The BO of a plant represents the number of links from the target plant to its neighbors, and the WO is the total strength of competition from the target plant to its neighbors. The analysis showed that the distributions of BO and WO were heavy-tailed in all years and that large plants had large BO and WO. These results suggest that only a few (i.e., large) plants have a very large impact on the growth and survival of a much larger number of neighboring plants and thus on population dynamics, whereas most of the others (i.e., small and medium-sized plants) have only a small impact on a few neighbors. By introducing binary and weighted connectivities (BC’ and WC’, respectively), we were able to identify the size classes of neighbors with which the target plant preferentially and strongly competed. The BC’ and WC’ results showed that large plants competed preferentially and more strongly with other large plants in 1948, but they competed more strongly with small plants after 1963. These results clarify targets of the very large impact of large plants, as shown by the results of BO and WO: the impact was exerted on the growth and survival of other large plants in 1948, whereas the impact was exerted on those of small plants after 1963. Our study demonstrates that the statistical properties of the competition network structure, which have been largely ignored in plant competition research, are important for understanding plant population dynamics.  相似文献   

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