The ornithophilous Anagyris foetida is almost the only shrub in the eastern Mediterranean region ... more The ornithophilous Anagyris foetida is almost the only shrub in the eastern Mediterranean region that flowers in winter. We assessed the pollination potential of flower visitors by observing pollen loads on trapped animals and contacts with floral parts. Resident and wintering omnivorous bird species, together with honey bees (Apis mellifera), were found to carry the shrub’s pollen throughout its long flowering period in Israel and thus might be legitimate pollinators. Spring-migrating omnivorous birds passing through Israel carried pollen. The Palestine Sunbird (Cinnyris osea) is the only specialist nectarivorous bird in the Middle East. It carries little pollen and is therefore primarily a nectar thief of A. foetida.
Soil microarthropods of pine forests in Israel were investigated for the first time. Eighty perce... more Soil microarthropods of pine forests in Israel were investigated for the first time. Eighty percent of them belonged to the orders Acari and Collembola, the remainder to another 18 orders. In the second post-fire year only 11 orders were presented. The groups Protura, Palpigradi and Pauropoda in Israel are described here for the first time. Protura and Pauropoda were quite common in the natural forest, but disappeared almost entirely after the fire. By contrast, the pseudococcid Rhizoecus sp., and to some extent also Palpigradi, were rare in unburned forest but behaved as pioneers and flourished two years post fire. The Collembolan fauna were studied in more detail and four genera new to Israel have been identified already. The family Poduridae was the most common Collembolan in natural forest, but they almost disappeared after the fire, while the entomobryoid springtails did not change too much. It was concluded that soil microarthropods play an important role in post-fire succession and are good indicators of resilience processes.
Fire in woodlands causes a dramatic decrease in rodent populations. The aim of this study was to ... more Fire in woodlands causes a dramatic decrease in rodent populations. The aim of this study was to detect rodent succession in three different management regimes of a post-fire habitat on Mount Carmel: (1) a control area of mixed woodlands of burnt pine and oak; (2) a mixed burnt woodland in which the burnt pine trees were cut and left in situ; and (3) a mixed burnt woodland in which burnt pines were cut and removed from the plot. Two plots in an unburnt mixed woodland were used as controls. The first invader species observed in the post-fire habitats were Mus macedonicus, which was the most abundant species in all burnt plots, Gerbillus dasyurus, which was mainly trapped in plots where the burnt pine trees were removed, and Meriones tristrami, which was mainly trapped in plots where the burnt pine trees were left in situ. The highest species diversity was recorded in the control plots of the burnt pine and oak woodland. In these burnt control plots the field mice (Apodemus) of both species reappeared. However, the numbers of trapped A. flavicollis were rather higher than of A. mystacinus. It is thus assumed that the invading species will be replaced by the originial woodland rodent species through resilience. *This study is dedicated in the memory of our colleague Mr. D. Banin.
When it comes to aging, some colonial invertebrates present disparate patterns from the customary... more When it comes to aging, some colonial invertebrates present disparate patterns from the customary aging phenomenon in unitary organisms, where a single senescence phenomenon along ontogeny culminates in their inevitable deaths. Here we studied aging processes in 81 colonies of the marine urochordate Botryllus schlosseri each followed from birth to death (over 720 days). The colonies were divided between three life history strategies, each distinct from the others based on the presence/absence of colonial fission: NF (no fission), FA (fission develops after the colony reaches maximal size), and FB (fission develops before the colony reaches maximal size). The study revealed recurring patterns in sexual reproductive statuses (hermaphroditism and male-only settings), colonial vigor, and size. These recurring patterns, collectively referred to as an Orshina, with one or more 'astogenic segments' on the genotype level. The combination of these segments forms the Orshina rhythm. E...
Rodent pests cause extensive damage to agricultural crops worldwide. Farmers’ ability to monitor ... more Rodent pests cause extensive damage to agricultural crops worldwide. Farmers’ ability to monitor rodent activity and damage within crops is limited due to their inability to simultaneously survey vast agricultural areas for rodent activity, the inability to enter certain fields, and the difficulty of monitoring rodent numbers, as well as using traps due to trap shyness and high labor costs. Drones can potentially be used to monitor rodent numbers and damage because they can cover large areas quickly without damaging crops and carry sensors that provide high-resolution imagery. Here, we investigated whether rodent activity (Levant voles Microtus guentheri and house mice Mus musculus) is related to vegetation health and biomass in Alfalfa (Medicago sativa) fields. We used a drone to photograph one hundred and twenty 10 × 10 m plots in nine fields and calculate the plots’ normalized difference vegetation index (NDVI) and biomass. On each plot, we also trapped rodents, counted rodent bu...
When it comes to aging, some colonial invertebrates present disparate patterns from the customary... more When it comes to aging, some colonial invertebrates present disparate patterns from the customary aging phenomenon in unitary organisms, where a single senescence phenomenon along ontogeny culminates in their inevitable deaths. Here we studied aging processes in 81 colonies of the marine urochordateBotryllus schlosserieach followed from birth to death (over 720 days). The colonies were divided between three life history strategies, each distinct from the others based on the existence/absence of colonial fission: NF (no fission), FA (fission develops after the colony reaches maximal size), and FB (fission develops before the colony reaches maximal size). Results revealed that sexual reproductive statuses (hermaphroditism and male only settings), colonial vigorousness and sizes, represent coinciding and repeated rhythms of one or more emerged life/death ‘astogenic segments’ on the whole-genet level, each is termed asOrshina, and the sum of all segments as theOrshinarhythm. EachOrshina...
Each of the few known life-history strategies (e.g., r/K and parity [semelparity and iteroparity]... more Each of the few known life-history strategies (e.g., r/K and parity [semelparity and iteroparity]), is a composite stratagem, signified by co-evolved sets of trade-offs with stochastically distributed variations that do not form novel structured strategies. Tracking the demographic traits of 81 Botryllus schlosseri (a marine urochordate) colonies, from birth to death, we revealed three co-existing novel life-history strategies in this long-standing laboratory-bred population, all are bracketed through colonial fission (termed NF, FA and FB for no fission, fission after and fission before reaching maximal colony size, respectively) and derived from organisms maintained in a benign, highly invariable environment. This environment allows us to capture the strategists’ blueprints and their net performance through 13 traits, each branded by high within-strategy variation. Yet, six traits differed significantly among the strategies and, in two, the FB was notably different. These results ...
Here we describe the structure elucidation and quantification of six glucosinolates (GSLs) from t... more Here we describe the structure elucidation and quantification of six glucosinolates (GSLs) from the roots of the desert plant Ochradenus baccatus, Delile 1813 (family Resedaceae; order Brassicales). The structure elucidation was established on the corresponding enzymatically desulfated derivatives of the native GSLs of the plant. Among these GSLs we describe the previously undescribed 2″-O-(α-L-arabinopyranosyloxy)benzylglucosinolate (1a), for which we propose the name glucoochradenin. The other five glucosinolates (2a-6a) were (2S)-2-hydroxy-2-phenylethylglucosinolate (2a; glucobarbarin), 2″-O-(α-L-rhamnopyranosyloxy)benzylglucosinolate (3a), benzylglucosinolate (4a; glucotropaeolin), indol-3-ylmethylglucosinolate (5a; glucobrassicin) and phenethylglucosinolate (6a; gluconasturtiin), all elucidated as their desulfo-derivatives, 2b-6b respectively). Structures were elucidated by MS and 1D and 2D-NMR techniques, the identity of the arabinose verified by ion chromatography, and the absolute configuration of the sugar units determined by hydrolysis, coupling to cysteine methyl-ester and phenyl isothiocyanate followed by HPLC-MS analysis of the resulted diastereomers. Response factors were generated for desulfo-2″-O-(α-L-arabinopyranosyloxy)benzylglucosinolate and for desulfo-2″-O-(α-L-rhamnopyranosyloxy)benzylglucosinolate and all six GSLs were quantified, indicating that the root of O. baccatus is rich in GSLs (Avg. 61.3 ± 10.0 μmol/g DW and up to 337.2 μmol/g DW).
The nutritious pulp of fleshy fruits facilitates seed dispersal via endozoochory. Frugivores are ... more The nutritious pulp of fleshy fruits facilitates seed dispersal via endozoochory. Frugivores are considered legitimate seed dispersers when they digest only the pulp but do not damage the seeds. Nevertheless, fruit pulp, in contrast to seeds, is low in nitrogen, thus potentially stimulating seed digestion in the fruit consumers, therefore raising a potential conflict of interest between the plant and the fruit consumer. Pycnonotus xanthopygos is an important distributor of seeds of the desert shrub, Ochradenus baccatus. Our study demonstrated that P. xanthopygos consumed fewer O. baccatus fruits compared with Musa acuminata, due to the presence of bioactive substances O. baccatus pulp juice. The passage of the O. baccatus seeds through the digestive system of P. xanthopygos resulted in damage of up to 80% of the seeds and 20% decrease in the weight of the defecated seeds. Despite the damage to the seeds, passage through the digestive system of P. xanthopygos significantly increased the germination of the surviving seeds. Pulp juice and/or drying of the fruits (on the shrub or in the laboratory) reduced seed germination, and separation of seeds from the pulp (manually or by the bird's digestive system) significantly increased germination. Our study demonstrated variable reduced digestibility of seeds and pulp when P. xanthopygos consumed O. baccatus fruits compared with M. acuminata. This effect was correlated with inhibition of digestive enzymes in O. baccatus fruits. Synthesis. Our results show that there is a complex interaction between Ochradenus baccatus and Pycnonotus xanthopygos where consumption of the fruits is both beneficial and harmful to the plant, due to seed damage on the one hand, yet promotion of seed germination on the other. This suggests that frugivory in general may benefit seed distributors and seed predators simultaneously, yet also highlights a potential conflict of interest inherent in endozoochory.
Scaffolds and contigs of Genomic DNA for Phaseolibacter flectens ATCC 12775T (Topology; linear, R... more Scaffolds and contigs of Genomic DNA for Phaseolibacter flectens ATCC 12775T (Topology; linear, Read depth; 1.00). (DOCX 24Â kb)
The ornithophilous Anagyris foetida is almost the only shrub in the eastern Mediterranean region ... more The ornithophilous Anagyris foetida is almost the only shrub in the eastern Mediterranean region that flowers in winter. We assessed the pollination potential of flower visitors by observing pollen loads on trapped animals and contacts with floral parts. Resident and wintering omnivorous bird species, together with honey bees (Apis mellifera), were found to carry the shrub’s pollen throughout its long flowering period in Israel and thus might be legitimate pollinators. Spring-migrating omnivorous birds passing through Israel carried pollen. The Palestine Sunbird (Cinnyris osea) is the only specialist nectarivorous bird in the Middle East. It carries little pollen and is therefore primarily a nectar thief of A. foetida.
Soil microarthropods of pine forests in Israel were investigated for the first time. Eighty perce... more Soil microarthropods of pine forests in Israel were investigated for the first time. Eighty percent of them belonged to the orders Acari and Collembola, the remainder to another 18 orders. In the second post-fire year only 11 orders were presented. The groups Protura, Palpigradi and Pauropoda in Israel are described here for the first time. Protura and Pauropoda were quite common in the natural forest, but disappeared almost entirely after the fire. By contrast, the pseudococcid Rhizoecus sp., and to some extent also Palpigradi, were rare in unburned forest but behaved as pioneers and flourished two years post fire. The Collembolan fauna were studied in more detail and four genera new to Israel have been identified already. The family Poduridae was the most common Collembolan in natural forest, but they almost disappeared after the fire, while the entomobryoid springtails did not change too much. It was concluded that soil microarthropods play an important role in post-fire succession and are good indicators of resilience processes.
Fire in woodlands causes a dramatic decrease in rodent populations. The aim of this study was to ... more Fire in woodlands causes a dramatic decrease in rodent populations. The aim of this study was to detect rodent succession in three different management regimes of a post-fire habitat on Mount Carmel: (1) a control area of mixed woodlands of burnt pine and oak; (2) a mixed burnt woodland in which the burnt pine trees were cut and left in situ; and (3) a mixed burnt woodland in which burnt pines were cut and removed from the plot. Two plots in an unburnt mixed woodland were used as controls. The first invader species observed in the post-fire habitats were Mus macedonicus, which was the most abundant species in all burnt plots, Gerbillus dasyurus, which was mainly trapped in plots where the burnt pine trees were removed, and Meriones tristrami, which was mainly trapped in plots where the burnt pine trees were left in situ. The highest species diversity was recorded in the control plots of the burnt pine and oak woodland. In these burnt control plots the field mice (Apodemus) of both species reappeared. However, the numbers of trapped A. flavicollis were rather higher than of A. mystacinus. It is thus assumed that the invading species will be replaced by the originial woodland rodent species through resilience. *This study is dedicated in the memory of our colleague Mr. D. Banin.
When it comes to aging, some colonial invertebrates present disparate patterns from the customary... more When it comes to aging, some colonial invertebrates present disparate patterns from the customary aging phenomenon in unitary organisms, where a single senescence phenomenon along ontogeny culminates in their inevitable deaths. Here we studied aging processes in 81 colonies of the marine urochordate Botryllus schlosseri each followed from birth to death (over 720 days). The colonies were divided between three life history strategies, each distinct from the others based on the presence/absence of colonial fission: NF (no fission), FA (fission develops after the colony reaches maximal size), and FB (fission develops before the colony reaches maximal size). The study revealed recurring patterns in sexual reproductive statuses (hermaphroditism and male-only settings), colonial vigor, and size. These recurring patterns, collectively referred to as an Orshina, with one or more 'astogenic segments' on the genotype level. The combination of these segments forms the Orshina rhythm. E...
Rodent pests cause extensive damage to agricultural crops worldwide. Farmers’ ability to monitor ... more Rodent pests cause extensive damage to agricultural crops worldwide. Farmers’ ability to monitor rodent activity and damage within crops is limited due to their inability to simultaneously survey vast agricultural areas for rodent activity, the inability to enter certain fields, and the difficulty of monitoring rodent numbers, as well as using traps due to trap shyness and high labor costs. Drones can potentially be used to monitor rodent numbers and damage because they can cover large areas quickly without damaging crops and carry sensors that provide high-resolution imagery. Here, we investigated whether rodent activity (Levant voles Microtus guentheri and house mice Mus musculus) is related to vegetation health and biomass in Alfalfa (Medicago sativa) fields. We used a drone to photograph one hundred and twenty 10 × 10 m plots in nine fields and calculate the plots’ normalized difference vegetation index (NDVI) and biomass. On each plot, we also trapped rodents, counted rodent bu...
When it comes to aging, some colonial invertebrates present disparate patterns from the customary... more When it comes to aging, some colonial invertebrates present disparate patterns from the customary aging phenomenon in unitary organisms, where a single senescence phenomenon along ontogeny culminates in their inevitable deaths. Here we studied aging processes in 81 colonies of the marine urochordateBotryllus schlosserieach followed from birth to death (over 720 days). The colonies were divided between three life history strategies, each distinct from the others based on the existence/absence of colonial fission: NF (no fission), FA (fission develops after the colony reaches maximal size), and FB (fission develops before the colony reaches maximal size). Results revealed that sexual reproductive statuses (hermaphroditism and male only settings), colonial vigorousness and sizes, represent coinciding and repeated rhythms of one or more emerged life/death ‘astogenic segments’ on the whole-genet level, each is termed asOrshina, and the sum of all segments as theOrshinarhythm. EachOrshina...
Each of the few known life-history strategies (e.g., r/K and parity [semelparity and iteroparity]... more Each of the few known life-history strategies (e.g., r/K and parity [semelparity and iteroparity]), is a composite stratagem, signified by co-evolved sets of trade-offs with stochastically distributed variations that do not form novel structured strategies. Tracking the demographic traits of 81 Botryllus schlosseri (a marine urochordate) colonies, from birth to death, we revealed three co-existing novel life-history strategies in this long-standing laboratory-bred population, all are bracketed through colonial fission (termed NF, FA and FB for no fission, fission after and fission before reaching maximal colony size, respectively) and derived from organisms maintained in a benign, highly invariable environment. This environment allows us to capture the strategists’ blueprints and their net performance through 13 traits, each branded by high within-strategy variation. Yet, six traits differed significantly among the strategies and, in two, the FB was notably different. These results ...
Here we describe the structure elucidation and quantification of six glucosinolates (GSLs) from t... more Here we describe the structure elucidation and quantification of six glucosinolates (GSLs) from the roots of the desert plant Ochradenus baccatus, Delile 1813 (family Resedaceae; order Brassicales). The structure elucidation was established on the corresponding enzymatically desulfated derivatives of the native GSLs of the plant. Among these GSLs we describe the previously undescribed 2″-O-(α-L-arabinopyranosyloxy)benzylglucosinolate (1a), for which we propose the name glucoochradenin. The other five glucosinolates (2a-6a) were (2S)-2-hydroxy-2-phenylethylglucosinolate (2a; glucobarbarin), 2″-O-(α-L-rhamnopyranosyloxy)benzylglucosinolate (3a), benzylglucosinolate (4a; glucotropaeolin), indol-3-ylmethylglucosinolate (5a; glucobrassicin) and phenethylglucosinolate (6a; gluconasturtiin), all elucidated as their desulfo-derivatives, 2b-6b respectively). Structures were elucidated by MS and 1D and 2D-NMR techniques, the identity of the arabinose verified by ion chromatography, and the absolute configuration of the sugar units determined by hydrolysis, coupling to cysteine methyl-ester and phenyl isothiocyanate followed by HPLC-MS analysis of the resulted diastereomers. Response factors were generated for desulfo-2″-O-(α-L-arabinopyranosyloxy)benzylglucosinolate and for desulfo-2″-O-(α-L-rhamnopyranosyloxy)benzylglucosinolate and all six GSLs were quantified, indicating that the root of O. baccatus is rich in GSLs (Avg. 61.3 ± 10.0 μmol/g DW and up to 337.2 μmol/g DW).
The nutritious pulp of fleshy fruits facilitates seed dispersal via endozoochory. Frugivores are ... more The nutritious pulp of fleshy fruits facilitates seed dispersal via endozoochory. Frugivores are considered legitimate seed dispersers when they digest only the pulp but do not damage the seeds. Nevertheless, fruit pulp, in contrast to seeds, is low in nitrogen, thus potentially stimulating seed digestion in the fruit consumers, therefore raising a potential conflict of interest between the plant and the fruit consumer. Pycnonotus xanthopygos is an important distributor of seeds of the desert shrub, Ochradenus baccatus. Our study demonstrated that P. xanthopygos consumed fewer O. baccatus fruits compared with Musa acuminata, due to the presence of bioactive substances O. baccatus pulp juice. The passage of the O. baccatus seeds through the digestive system of P. xanthopygos resulted in damage of up to 80% of the seeds and 20% decrease in the weight of the defecated seeds. Despite the damage to the seeds, passage through the digestive system of P. xanthopygos significantly increased the germination of the surviving seeds. Pulp juice and/or drying of the fruits (on the shrub or in the laboratory) reduced seed germination, and separation of seeds from the pulp (manually or by the bird's digestive system) significantly increased germination. Our study demonstrated variable reduced digestibility of seeds and pulp when P. xanthopygos consumed O. baccatus fruits compared with M. acuminata. This effect was correlated with inhibition of digestive enzymes in O. baccatus fruits. Synthesis. Our results show that there is a complex interaction between Ochradenus baccatus and Pycnonotus xanthopygos where consumption of the fruits is both beneficial and harmful to the plant, due to seed damage on the one hand, yet promotion of seed germination on the other. This suggests that frugivory in general may benefit seed distributors and seed predators simultaneously, yet also highlights a potential conflict of interest inherent in endozoochory.
Scaffolds and contigs of Genomic DNA for Phaseolibacter flectens ATCC 12775T (Topology; linear, R... more Scaffolds and contigs of Genomic DNA for Phaseolibacter flectens ATCC 12775T (Topology; linear, Read depth; 1.00). (DOCX 24Â kb)
Uploads
Papers by Ido Izhaki