Browsing by Author "Neelkamal Rastogi"

Now showing 1 - 20 of 30

A single lycaenid caterpillar gets an ant-constructed shelter and uninterrupted ant attendance
(Blackwell Publishing Ltd, 2019) Priya Aradhya Ekka; Neelkamal Rastogi
Ant-lycaenid associations range from mutualism to parasitism and the caterpillars of some species of lycaenids are reported to enter ant nests for shelter, diapause, or pupation. The present study aimed to examine the nature of the association between Euchrysops cnejus (Fabricius) (Lepidoptera: Lycaenidae) and Camponotus compressus (Fabricius) (Hymenoptera: Formicidae) worker ants on the extrafloral nectary-bearing cowpea plant, Vigna unguiculata (L.) Walp. (Fabaceae). The abundance patterns of the ants and the lycaenid caterpillars together with the spatial patrolling patterns of the ants on the plants revealed that ant abundance increased with the occurrence of the lycaenid caterpillars and the ants preferred the lycaenids over the extrafloral nectar. Camponotus compressus worker ants constructed a shelter at the cowpea plant base after interaction with one or more lycaenid caterpillar(s) and tended the caterpillars and pupae till the emergence of the butterfly. The ant-constructed shelters (ACSs) inhabited by the minor caste workers (13 ± 1.3 ants per ACS), were utilized by the caterpillars to undergo pupation. The ants confined their activities predominantly to tending the pod-feeding caterpillars and the solitary pupa within each ACS. It appears that the behavior of the tending worker ants is modulated by the lycaenid vulnerable stages. © 2019 The Netherlands Entomological Society
Ant fauna of the Indian Institute of Science campus survey and some preliminary observations
(1997) Neelkamal Rastogi; Padmini Nair; Milind Kolatkar; Harry William; Raghavendra Gadagkar
On the basis of a survey of ants on the campus of the Indian Institute of Science, a checklist of species and brief descriptions of commonly seen nests is provided. Some observations, especially on diets and daily foraging patterns in a few selected species are also presented. The main objective of this study was to explore the potential of the campus ant fauna for future work in behaviour and ecology.
Ants as dominant insect visitors of the extrafloral nectaries of sponge gourd plant, Luffa cylindrica (L.) (Cucurbitaceae)
(2010) Vivek Mohan Agarwal; Neelkamal Rastogi
The button-shaped extrafloral nectaries (EFNs) located on the bracts, bracteoles, calyces and leaves of cultivated sponge gourd plant, Luffa cylindrica, were visited by insects belonging to five different orders: Hemiptera, Diptera, Coleoptera, Hymenoptera, and Lepidoptera. Insects with biological-control potential recorded at the EFNs included ants, wasps and ladybird beetles. Ants, comprising ten species, constituted by far the most abundant group (84.44 ± 4.34 % of individuals) at the EFNs. Insect pollinators included honey bees, butterflies and wasps, which, while visiting the floral nectaries (FNs), also visited the EFNs. Ants were found in large numbers on EFN-bearing plant parts, particularly leaves and calyces. Aggressive and abundant ant species visiting the plants included Camponotus compressus, C. paria and Pheidole sp. The major insect herbivore was the red pumpkin beetle, Raphidopalpa foveicollis Lucas, which fed predominantly on the corolla of the plants and, to a lesser extent, on each of the EFN-bearing vegetative parts. The low abundance of herbivores on vegetative parts indicates that the ants and, to a lesser extent, wasps, bees and ladybirds visiting the EFN-bearing plant structures may be aiding in crop plant protection from the herbivores. Thus, though the EFNs of sponge gourd plants attract predators, pollinators and also extrafloral nectar thieves such as flies, ants are the major group involved in the facultative association with the annual crop plant. Such studies may aid an environmentally-friendly management approach involving the natural enemies of insect pests of EFN-bearing annual crop plants. © Vivek Mohan Agarwal and Neelkamal Rastogi.
Ants as pollination vectors of ant-adapted Euphorbia hirta L. plants
(Springer Science and Business Media B.V., 2022) Joy Nivedita Samuel; Neelkamal Rastogi
A wide range of ant-plant mutualistic associations are known to occur in terrestrial ecosystems. Although many species of plants recruit ants to obtain protection from herbivores, myrmecophily is rare, since only few plant species are known to be adapted for pollination predominantly by ants. The annual herb, Euphorbia hirta, is characterized by the ‘ant-pollination syndrome’ including traits such as unisexual flowers, inconspicuous cyathia clustered in globose cymes, inflorescence-associated tiny nectaries and short, semi-erect stem. In present study, we aimed to examine the pollination ecology of Euphorbia hirta and the role of ants in its pollination. Field and laboratory experiments conducted to understand the association between E. hirta plants and ants revealed that seven ant species (belonging to five genera and three subfamilies) visited E. hirta plants. The visitation patterns of ants revealed that in a single foraging trip the ants visited a number of plants indicating their potential role in cross-pollination. Field-based exclusion experiments revealed production of significantly higher number of fruits in E. hirta plants under open pollination treatment as compared to other treatments. Scanning electron microscopy revealed that the adherence of the pollen grains to the bristles located on ant mouth-parts was facilitated by the three vertical, semi-circular grooves present on the grain surface. The number of fruits produced per plant was higher in ant-included plants as compared to only winged insect-pollinated and only self-pollinated plants suggesting that the plant-visiting ants are successful pollination vectors of E. hirta and while promoting self-pollination also contribute towards cross-pollination services. © 2022, The Author(s), under exclusive licence to Springer Nature B.V.
Bio-transfer and bioaccumulation patterns of heavy metals in mine site-inhabiting ants and grasshoppers, across mine site restoration chronosequence
(Springer, 2023) Shbbir R. Khan; Neelkamal Rastogi; Satish K. Singh
Soil is known to serve as a significant sink for heavy metals in coal mine sites, thus also influence the plant and other organisms of that area. Hence, the presence of heavy metals in coal mine soil is of concern to land managers. Insects occupy different trophic positions in the food chains, thus many insect species accumulate large amounts of heavy metals in their bodies and this is a matter of concern. In the present study, we investigated biotransfer and bioaccumulation of heavy metals from soil, grass species Cynodon dactylon, Vetiveria zizanioides, grasshopper species Gastrimargus africanus, Choroedocus robustus, ant species Cataglyphis longipedem and Camponotus compressus in six different ages (2, 4, 6, 8, 10 and 12 year old) of coal mine sites. Our study revealed that at some extent the heavy metal content and BAF patterns of heavy metals along different pathways (from soil to grass, soil to grasshoppers and from grass to grasshoppers) were not consistent and did not reflect the soil pollution status for all the metals, related to the mine spoil dump age. However, in contrast, ants successfully reflected a consistent pattern in the bioaccumulation of heavy metals via soil, thereby indicating the pollution status of the soil along with the restoration age of mine spoil dumps. Our study showed that ant species can successfully forecast the presence of heavy metals of coal mine spoils along with their restoration. © 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Can a common and abundant plant-visiting ant species serve as a model for nine sympatric ant-mimicking arthropod species?
(Indian Academy of Sciences, 2018) Sudha Kumari; Neelkamal Rastogi
Many arthropods mimic ants to avoid predation risk from visual predators. Our study of ant-mimicking arthropod diversity revealed 10 sympatric myrmecomorphs including spiders, mantids, bugs and grasshoppers. All, except one, were found predominantly on extrafloral nectary-bearing and homopteran harbouring plants. Of the five plant-visiting ant species, Camponotus compressus, Camponotus paria, Camponotus sericeus, Crematogaster subnuda and Tapinoma melanocephalum, only C. compressus showed significantly high occurrence and abundance on these plants. Except for a small spider morph, the remaining nine myrmecomorphic species resembled C. compressus and apparently use this common and abundant ant species as their model. © 2018 Current Science Association.
Contribution of the nutrient-enriched ant nest debris soil to growth and yield of Kalmegh (Andrographis paniculata) under natural and experimental field conditions
(Taylor and Francis Ltd., 2018) Rakesh K. Shukla; Neelkamal Rastogi; Hema Singh
Andrographis paniculata, commonly known as Kalmegh, is an important medicinal plant which exhibits a range of pharmacological characteristics. The present study revealed that under natural and experimental field conditions, the debris soil of the ground-nesting ant (Pheidole latinoda) colonies increased soil fertility and yield of this plant. The growth of Kalmegh planted in the debris amended soil was significantly enhanced in a dose-dependent manner. The yield, in terms of number of branches, number of leaves, plant biomass and number of pods plant−1 was consistently higher for plants grown in debris amended treatments as compared with plants grown in control soil. Concentrations of total C, P, available N (NH4-N, NO3-N) and microbial biomass C and P were significantly higher in the various debris amended soil treatments as compared with the control soil. Significant positive correlations were found between the ecophysiological traits of Kalmegh plants, i.e. leaf area, total biomass and number of fruits plant−1, and the soil chemical properties of the soil. Under natural field conditions also the biomass of Kalmegh plants growing within 5 m distance of P. latinoda nests was significantly higher as compared with plants located at a distance >10 m. Overall, the results suggested that the ecosystem engineering activities of P. latinoda colonies have the potential to contribute to soil fertility and thereby promote enhanced growth and yield of this medicinally important plant. Since colonies of ground-nesting ant species, such as P. latinoda, are abundant in annual cropping systems, they can contribute to agricultural sustainability. © 2017 Informa UK Limited, trading as Taylor & Francis Group.
Crucial role of the landscape 'matrix' in determining biodiversity within fragmented habitats
(1996) Neelkamal Rastogi
[No abstract available]
Deterrent effect of a guild of extrafloral nectary-visiting ant species on Raphidopalpa foveicollis, a major insect pest of sponge gourd, Luffa cylindrica
(2008) Vivek M. Agarwal; Neelkamal Rastogi
Among the 10 ant species visiting the extrafloral nectaries of sponge gourd plants [Luffa cylindrica L. (Cucurbitaceae)], Camponotus compressus (Fabricius) (Hymenoptera: Formicidae) appears to be the ecologically dominant species, due to its abundance and the high frequency of deterrent encounters with the major insect herbivore, Raphidopalpa foveicollis Lucas (Coleoptera: Chrysomelidae). A significant positive linear correlation was found between the number of extrafloral nectaries per leaf, calyx, bract, and bracteole and the patrolling time of C. compressus, Camponotus paria (Emery), Pheidole spec., and Tetramorium spec. (all Hymenoptera: Formicidae) at the corresponding plant parts. Many one-to-one deterrent interactions between the ant visitors and adult R. foveicollis were recorded, with C. compressus being involved in most encounters on the calyx and bracts, Pheidole spec. on the leaves, and Pachycondyla tesserinoda (Emery) (Hymenoptera: Formicidae) on the bracteoles. Tapinoma melanocephalum (Fabr.) (Hymenoptera: Formicidae) exhibited significant deterrent effects on adult herbivores on the corolla when in groups larger than 15 ants. Ant exclusion and inclusion experiments revealed a significant reduction in the residence time, as well as dose- and time-dependent reduction in the frequency of visits of the herbivore on crop plants with C. compressus, C. paria, Pheidole spec., and T. melanocephalum ants, compared to the control. Results support the optimal defence hypothesis, as the plant structures most closely linked to plant fitness bear the extrafloral nectaries and are defended by the visiting ant species. This is a valuable, indirect plant-protection strategy of an annual crop plant. © 2008 The Authors.
Differences in the behaviour of model and non-model species of ants in interactions with the pod-sucking myrmecomorphic bug Riptortus linearis (Hemiptera: Alydidae)
(Czech Academy of Sciences, 2021) Joy Nivedita Samuel; Neelkamal Rastogi
Ants are common invertebrate models of many myrmecomorphic arthropods since they are unpalatable and pose a threat for many species. Natural habitats harbour a diverse community of different species of ants and their mimics. The myrmecomorphic bug, Riptortus linearis uses a variety of extrafloral nectary-bearing or hemipteran-harbouring legumes as host plants, which are also visited by various sugar-loving species of ants. In the present study, we investigated the responses of the antmimicking and non-mimicking stages of the pod-sucking bug, Riptortus linearis, its ant model, Camponotus compressus and a co-occurring ant, Crematogaster subnuda, during experimental encounters, under laboratory conditions. Cr. subnuda ants were much more aggressive than Ca. compressus ants towards the myrmecomorphic bug. However, the pod-sucking bug exhibited similar responses to both of the species of ants. More importantly, Ca. compressus ants did not bite the first instar nymph of the bug. The results of this study show that the non-model ant was significantly more aggressive than the ant model towards different stages of R. linearis. These results have important implications for the management of the pod-sucking bug, R. linearis, which is an important pest of many legumes. © 2021. All Rights Reserved.
Do Ant-Mediated Multitrophic Interactions Enhance the Fitness of an Aphid-Infested Extrafloral Nectary-Bearing Plant?
(Springer, 2022) Joy Nivedita Samuel; Neelkamal Rastogi
The net effect of multitrophic interactions among members (belonging to various feeding guilds such as herbivores, predators) of arboreal arthropod assemblages on the host plants may be enhancement in herbivory or in protection of the plants. Many species of ants are arboreal foragers on extrafloral-nectary (EFN)-bearing and/or harboring honeydew producing hemipterans. The present study reports the consequence of multispecies interactions among ants, ant-tended aphids, other insect herbivores and predators on the fitness of an EFN-bearing plant, Clerodendrum infortunatum. By manipulating the presence of ants and arthropod predators on the plants, ant presence was found to increase aphid abundance but reduced the abundance of three species of insect herbivores and two species of arthropod predators on the plants. The plants’ fitness (number of flowers/buds and fruits) was significantly higher in the presence of ants irrespective of the presence or absence of arthropod predators. The fitness of the plants was significantly low when both the ants as well as the arthropod predators were excluded from the plants. We suggest that the presence of aggressive ant bodyguards on the plants accounts for the reduced occurrence of other damage-causing insect herbivores, resulting in a net positive impact on the plant fitness. Our study suggests that the fitness gains of the EFN-bearing plants arise due to the facultative association between the sugar-loving, ant species and EFN-bearing plants and multitrophic interactions among the aphid-tending ants, diverse insect herbivores and the arthropod predators attracted to the plants due to the presence of potential aphid prey. © 2022, The National Academy of Sciences, India.
Do the food availability conditions influence the stage-specific prey choice and predation attributes of agroecosystem-inhabiting spiders?
(Springer, 2022) Abhinav Mishra; Bhupendra Kumar; Neelkamal Rastogi
Present study was designed to assess the predation attributes of the hunting (Oxyopes javanus and Pardosa sumatrana) and web-weaving (Neoscona theisi and Tetragnatha javana) spiders on the wingless and winged stages of the economically important wheat aphid (Sitobion avenae) pests under varying prey quantity conditions. The experiments were carried out in two parts. First part included optimization of the experimental prey conditions (scarce/ optimal/ abundant) per spider species. The second part assessed the consumption rate, conversion efficiency and growth rate of each of the four spider species under fluctuating experimental prey conditions. Results revealed that: (1) irrespective of the spider species, predation attributes (viz. consumption rates, conversion efficiencies and growth rates) were highest on scarce prey and lowest on abundant prey; (2) amongst the four spider species, larger spiders (i.e. N. theisi and O. javanus) had higher prey consumption and utilization efficiencies over the smaller ones (T. javana and P. sumatrana); and (3) all species of spiders utilized higher biomass of wingless as compared to winged morphs under optimal and abundant conditions but displayed no such significant differences in consumption patterns under scarce conditions. The present results therefore reveal that the four studied spider species exhibit compensatory feeding under prey scarce conditions. However, larger species are more efficient in overcoming scarce prey conditions than the smaller species. Since spiders have enormous potential as biological control agents the results would be of significance in the management of wheat aphids. © 2022, International Society for Tropical Ecology.
Does prey characteristics influence web-building plasticity of the ecologically dominant orb-web weaving spider, Neoscona theisi (Walckenaer 1841)?
(Institute for Ionics, 2023) Abhinav Mishra; Neelkamal Rastogi
Spiders are the pre-eminent silk producers and many species construct orb webs to capture the insect prey. The present study was focused on the design and the orientation patterns of Neoscona theisi orb webs, during the crop growing seasons of rice and wheat. Architectural design of webs constructed by the orb web spider was examined in the crop fields by walking through the fields to locate the spider webs. Results revealed that web height and diameter increased along with increase in the diversity and availability of insect pests of rice. The proportion of vertically oriented webs of N. theisi increased progressively with increase in the availability of highly active and large-sized, prey in the paddy fields. In the wheat agroecosystem, the proportion of spiders without webs increased in response to the availability of the most abundant, small sized (with very low mobility) aphid prey, Sitobion avenae. It is likely that the adaptive plasticity in web size and orientation patterns exhibited by N. theisi not only helps it to maximize its prey capture efficiency but also plays an important role in contributing towards its dominance among the orb web-making species. © 2022, African Association of Insect Scientists.
Exploring the influence of ground-dwelling ant bioturbation activity on physico-chemical, biological properties and heavy metal pollution in coal mine spoil
(Elsevier GmbH, 2024) Shbbir R. Khan; Poonam C. Singh; Martin Schmettow; Satish K. Singh; Neelkamal Rastogi
Coal mining activities increase the soil concentrations of heavy metals manifold thus impacting soil health and biodiversity. The understanding of the impact of bioturbation activities by ant colonies on soil in coal mine spoil site across different restoration ages is not studied. The study aimed to investigate the influence of bioturbation activities by two most common and distinct coal mine site inhabiting ant species (C. compressus and C. longipedem) at six different ages (2, 4, 6, 8, 10 and 12 years old) on the soil heavy metal concentrations of Fe, Zn, Mn, Cu, Ni, Pb, Cd and Cr, pH, OM, TC, TN, soil enzyme activity of DH, ACP, β-glucosidase and proteases properties of soil. Soil samples were collected from opencast coalmine spoils during October and November 2017. Reference (Ref.) soil samples (n=10 per site) were collected (from area adjacent to ant nest colony approximately 2–5 m distance) from a depth of 0–15 cm and ant nest debris soil of each ant species (n=10 per site) were collected from each site. Heavy metal pollution decreased and pH, OM, TC, TN and soil enzyme activity of DH, ACP, β-glucosidase and proteases of soil in both Ref. soil and ant nest debris soil increases with the increase of mine site restoration age. Our study revealed that different age of the mine spoil have more profound effects on the soil quality and heavy metal content. Contrary to our hypothesis, regression analysis did not support our notion that ant bioturbation activity directly accelerate heavy metal breakdown. Instead, our findings suggests that ant colonies prefer to construct their nest for the locations with lower heavy metal concentrations and higher enzyme activity and increase in soil porosity is a key factor behind the low heavy metal concentration in the nest debris soil. © 2024 Elsevier GmbH
Facultative associations of two sympatric lycaenid butterflies with camponotus compressus – field study and larval surface ultrastructure
(Department of Zoology and Environmental Sciences, 2020) Priya Aradhya Ekka; Sudha Kumari; Neelkamal Rastogi
The present study focused on the associations of two sympatric lycaenid species, Chilades pandava Horsfield, 1829 and Euchrysops cnejus Fabricius, 1798 with their respective host plants and the lycaenid tending Camponotus compressus Fabricius, 1787 ants by conduction of field studies and by examination of the ultrastructure of the larval myrmecophilous organs. The study revealed two facultative association complexes: ants-the defoliating Cl. pandava larvae-Cycas revoluta (Thunb.) plants and ants-the pod-boring E. cnejus larvae-cowpea plant, Vigna unguiculata (L.) Walp. The association of Cl. pandava was strongly synchronized with its host plant phenology and relatively less strongly with its late-arriving ant partner since the young, curled up leaves provided resources only to the caterpillars. The provision of resources to both the ants and the lycaenids by the cowpea plants contributed to the synchronization of E. cnejus association with the early arriving ants as well as the host plant. Presence of a single type of setae in Cl. pandava and of two types of setae in E. cnejus larvae indicates their facultative adaptations for resisting attack by their host ants. Ultrastructural similarity in the dorsal nectary, pore cupola and tentacle organs suggest that the basic myrmecophilous organs are conserved in these two lycaenid species. © PRIYA ARADHYA EKKA, SUDHA KUMARI AND NEELKAMAL RASTOGI.
Food resource and temporal partitioning amongst a guild of predatory agroecosystem - inhabiting ant species
(Chinese Academy of Sciences, 2009) Vivek Mohan Agarwal; Neelkamal Rastogi
Prey diversity and temporal foraging patterns of six abundant, predatory ant species were investigated seasonally in an agroecosystem with two main vegetable crops. Pheidole sp. demonstrated the highest predation success and therefore appears to be the dominant species while Tapinoma melanocephalum showed the lowest success under the natural field conditions. Investigation of prey diversity and temporal activity patterns with the null model tests of niche overlap revealed a significant overlap indicating that the activity periods and prey diversity may not be solely influenced by interactions among the co-existing ant species. However, niche partitioning in the daily peak activity periods was demonstrated during all the three seasons (summer, rainy and winter) particularly between Pheidole sp. and T. melanocephalum. Pheidole sp. exhibited a high intensity, broadly extended mono-modal foraging pattern. Camponotus compressus and C. paria showed bi-modality in their foraging activity during the rainy season and mono-modal patterns during summer and winter seasons. Pachycondyla tesserinoda, Tetramorium sp. and T. melanocephalum exhibited peak foraging activities in the morning hours during the summer and rainy seasons. The activity profiles of C. compressus and T. melanocephalum were skewed towards late afternoon hours during the winter season indicating avoidance of foraging activity during the favourable periods when the more aggressive Pheidole sp. is active. In the sponge gourd agroecosystem, the ants captured predominantly hymenopteran, orthopteran and coleopteran insects. While Pheidole sp. hunted mainly the large orthopteran prey, other ant species captured worker ants in the sponge gourd agroecosystem. In the cauliflower agroecosystem, while other species captured prey chiefly belonging to six orders, i.e., Lepidoptera, Hymenoptera, Coleoptera, Hemiptera, Isoptera and Diptera, Pheidole sp. was the only species to also hunt orthopteran prey. The agroecosystem-inhabiting ant species prey on a large number and wide variety of insect herbivores as evident from the differences in the peak foraging times and the proportion of each type of prey hunted. Overall, our results indicate that the structure of agroecosystem-inhabiting ant assemblage may be influenced by a variety of factors including competition, temporal heterogeneities, prey availability and its characteristics such as size and mobility. © 2009 Current Zoology.
Functional biodiversity and ecophysiology of animals
(2009) Neelkamal Rastogi; Dinesh Kumar
[No abstract available]
Gerris spinolae Lethierry and Severin (Hemiptera: Gerridae) and Brachydeutera longipes Hendel (Diptera: Ephydridae): Two effective insect bioindicators to monitor pollution in some tropical freshwater ponds under anthropogenic stress
(Hindawi Limited, 2012) Arijit Pal; Devashish Chandra Sinha; Neelkamal Rastogi
The abundance patterns of two insects, Gerris spinolae and Brachydeutera longipes, were found to be affected by abiotic aquatic factors including free carbon dioxide, dissolved oxygen, BOD, and phosphate concentrations prevailing in four tropical freshwater ponds, three of which being anthropogenically stressed. Regression analysis between each individual-independent water quality variable and insect abundance demonstrated a significant positive correlation in each case between B. longipes abundance and BOD, phosphate, free CO 2, and algae dry weight, while a significant negative correlation of each of these variables was found with Gerris spinolae abundance. Moreover, a significant negative correlation of B. longipes abundance was calculated with dissolved oxygen concentration, while G. spinolae abundance exhibited a positive correlation with the same. Thus, G. spinolae appears to be a pollution sensitive, effective bioindicator for healthy unpolluted ponds, while B. longipes has potential as a pollution-resistant insect species indicative of pollution occurrence. Copyright © 2012 Arijit Pal et al.
Heavy metal accumulation and ecosystem engineering by two common mine site-nesting ant species: implications for pollution-level assessment and bioremediation of coal mine soil
(Springer International Publishing, 2017) Shbbir R. Khan; Satish K. Singh; Neelkamal Rastogi
The present study focuses on the abundance, heavy metal content, and the impact of ecosystem engineering activities of two coal mine site-inhabiting ant species, Cataglyphis longipedem and Camponotus compressus. The abundance of Ct. longipedem increased while that of C. compressus decreased, with increasing soil pollution. Correspondence analysis reveals a close association between soil heavy metal concentrations and Ct. longipedem abundance, but this association is lacking in the case of C. compressus. Cataglyphis ants which occupy stress-characterized niches appear to be pre-adapted to tolerate heavy metal pollution. Higher concentrations of Zn and Mn in Ct. longipedem may contribute to the strengthening of the cuticular structures, necessary for nest excavation in the hard, arid soil and for single load carrying. C. compressus ants appear to be pollution sensitive. Their higher Fe content may be related to metal uptake via plant-derived liquids and species-specific regulatory mechanisms. The metal pollution index and biota-to-soil accumulation factors, calculated by using the ant body metal content of the two species, indicate an overall decrease of soil heavy metal concentrations with increase of the site age, which reflects the degree of pollution related to the mine site age. The concentrations of total and available heavy metals (Fe, Zn, Mn, Pb, and Cu) were significantly lower in the ant nest debris soil as compared to the reference soil. The results of the present study highlight the role of ants as bioindicators and in bioremediation of contaminated soil. © 2017, Springer International Publishing Switzerland.
How effective are disturbance – tolerant, agroecosystem – nesting ant species in improving soil fertility and crop yield?
(Elsevier B.V., 2016) Rakesh K. Shukla; Hema Singh; Neelkamal Rastogi
Study of the abundance, diversity and nest densities of agroecosystem-inhabiting ant species, in fallow, freshly tilled and cultivated farmers’ fields revealed that Pheidole latinoda had highest abundance, nest density and disturbance-tolerance ability. Thirty-one arthropod morphospecies belonging to 12 orders were recorded in the nest entrance rim debris piles of this ant species. Hence, P. latinoda was selected to study the impact of nest rim debris soil on soil fertility and yield of two common crops, rice and tomato, widely cultivated in the Indo-Gangetic plains of India. Experimental field studies revealed that ant-related enrichment results in significant increase of the C, N and P contents of the bulk soil and a doubling of the soil microbial biomass. The soil enrichment significantly enhanced the yield of both the crop plants in a dose-dependent manner. A significant positive correlation was found between the ecophysiological traits including the specific leaf area, plant height and total plant weight of both rice and tomato plants, and the soil chemical constituents i.e. total C, N, P, NH4-N, NO3-N, microbial biomass C, N and P. The ecosystem engineering activities of P. latinoda ant colonies apparently enriched the soil via the nutrient cycling activities of the debris arthropods, on the externally discarded organic refuse. Since P. latinoda increases productivity via increase in soil fertility and also has the potential to suppress insect pests of crops, conservation of such ant species could enhance agricultural sustainability, through multiple pathways. © 2016 Elsevier B.V.