Murugan R.,University of Kassel |
Kumar S.,University of Agricultural Sciences, Bangalore
Biology and Fertility of Soils | Year: 2013
Amino sugars, as a microbial residue biomarker, are highly involved in microbial-mediated soil organic matter formation. However, accumulation of microbial biomass and responses of bacterial and fungal residues to the management practices are different and poorly characterized in rice soils. The objectives of this study were to evaluate the effects of mineral fertiliser (MIN), farmyard manure (FYM) and groundnut oil cake (GOC) on crop yield and co-accumulation of microbial residues and microbial biomass under rice-monoculture (RRR) and rice-legume-rice (RLR) systems. In the organic fertiliser treatments and RLR, rice grain yield and stocks of soil and microbial nutrients were significantly higher than those of the MIN treatment and RRR, respectively. The increased presence of saprotrophic fungi in the organic fertiliser treatments and RRR was indicated by significantly increased ergosterol/Cmic ratio and extractable sulphur. In both crop rotation systems, the long-term application of FYM and GOC led to increased bacterial residues as indicated by greater accumulation of muramic acid. In contrast, the higher fungal C/bacterial C ratio and lower ergosterol/Cmic ratio in the MIN treatment, is likely caused by a shift within the fungal community structure towards ergosterol-free arbuscular mycorrhizal fungi (AMF). The organic fertiliser treatments contributed 22 % more microbial residual C to soil organic C compared to the MIN treatment. Our results suggest that the negative relationship between the ratios ergosterol/Cmic and fungal C/bacterial C encourages studying responses of both saprotrophic fungi and AMF when assessing management effects on the soil microbial community. © 2013 Springer-Verlag Berlin Heidelberg.
Viraktamath C.A.,University of Agricultural Sciences, Bangalore |
Dietrich C.H.,University of Illinois at Urbana - Champaign
Zootaxa | Year: 2011
Sweta gen. n. is described and illustrated based on type species S. hallucinata sp. n. from northeast India and Thailand and placed in the typhlocybine tribe Dikraneurini. The new genus is unique among known Typhlocybinae in having the pronotum enlarged and extended to the scutellar suture. This feature is characteristic of the related subfamily Signoretii-nae, but among other subfamilies is restricted to a few brachypterous forms. Copyright © 2011 - Magnolia Press.
Aghera N.,Tata Institute of Fundamental Research |
Earanna N.,University of Agricultural Sciences, Bangalore |
Udgaonkar J.B.,Tata Institute of Fundamental Research
Biochemistry | Year: 2011
To improve our understanding of the contributions of different stabilizing interactions to protein stability, including that of residual structure in the unfolded state, the small sweet protein monellin has been studied in both its two variant forms, the naturally occurring double-chain variant (dcMN) and the artificially created single-chain variant (scMN). Equilibrium guanidine hydrochloride-induced unfolding studies at pH 7 show that the standard free energy of unfolding, ΔG°U, of dcMN to unfolded chains A and B and its dependence on guanidine hydrochloride (GdnHCl) concentration are both independent of protein concentration, while the midpoint of unfolding has an exponential dependence on protein concentration. Hence, the unfolding of dcMN like that of scMN can be described as two-state unfolding. The free energy of dissociation, ΔG°d, of the two free chains, A and B, from dcMN, as measured by equilibrium binding studies, is significantly lower than ΔG°U, apparently because of the presence of residual structure in free chain B. The value of ΔG°U, at the standard concentration of 1 M, is found to be ∼5.5 kcal mol-1 higher for dcMN than for scMN in the range from pH 4 to 9, over which unfolding appears to be two-state. Hence, dcMN appears to be more stable than scMN. It seems that unfolded scMN is stabilized by residual structure that is absent in unfolded dcMN and/or that native scMN is destabilized by strain that is relieved in native dcMN. The value of ΔG°U for both protein variants decreases with an increase in pH from 4 to 9, apparently because of the thermodynamic coupling of unfolding to the protonation of a buried carboxylate side chain whose pKa shifts from 4.5 in the unfolded state to 9 in the native state. Finally, it is shown that although the thermodynamic stabilities of dcMN and scMN are very different, their kinetic stabilities with respect to unfolding in GdnHCl are very similar. © 2011 American Chemical Society.
Viraktamath C.A.,University of Agricultural Sciences, Bangalore
Zootaxa | Year: 2011
The tribe Agalliini of the subfamily Megophthalminae is revised for the Oriental and Australian regions. Fifteen genera and 86 species have been recognized including 6 new genera, 40 new species, 7 new synonyms and 9 new combinations. The new genera and species described are Austroagallia balii sp. nov. (Indonesia: Bali Is.), A. distanti sp. nov. (India:Karnataka), A. prachuabensis sp. nov. (India, Thailand), Formallia gen. nov., F. ishiharai sp. nov.(Taiwan), F. longipenis sp. nov. (Taiwan), F. longistyla sp. nov. (Taiwan), F. rugosa sp. nov. (Taiwan), F. truncata sp. nov. (type sepcies) (Taiwan), Hemagallia gen. nov. (type-species: Agallia plotina Distant), Ianagallia gen. nov. (type-species Austroagallia bifurcata Sawai Singh & Gill), Igerna aurora sp. nov. (Sunda Is, Timor Is.), I. darjeelingensis sp. nov. (India: Sikkim, West Bengal), I. delineata sp. nov. (India: Tamil Nadu), I. himalayensis sp. nov. (India: West Bengal), I. keyae sp. nov. (India: Sikkim), I. priyankae sp. nov. (India: Himachal Pradesh, Meghalaya. Nepal), I. quinlani sp. nov. (Nepal), I. sikkima sp. nov. (India: Sikkim), I. wilsoni sp. nov. (India: West Bengal), Japanagallia asymmetrica sp. nov. (China: Fukien), J. curvata sp. nov. (China: Fukien), J. javana sp. nov. (Indonesia: Java), J. longipenis sp. nov. (China: Fukien), J. malaisei sp. nov. (Myanmar), J. mussooriensis sp. nov. (India: Uttar Pradesh), J. neotappana sp. nov. (China: Fukien), J. nepalensis sp. nov. (Nepal), J. peculiaris sp. nov. (Nepal), J. sumatrana sp. nov. (Indonesia: Sumatra), J. yoshimotoi sp. nov. (Taiwan), Nandigallia gen. nov. N. matai sp. nov. (India: West Bengal; China: Fukien), N. nandiensis sp. nov. (type-species) (India: Karnataka, Maharashtra), Paulagallia gen. nov., P. maai sp. nov. (Malaysia: Borneo: Sabah), P. punctata sp. nov. (type-species)( Malaysia: Borneo: Sabah), Sangeeta gen. nov. S. dentata sp. nov. (Indonesia: Pahang), S. dlabolai sp. nov. (Laos), S. fyanensis sp. nov. (Vietnam), S. linnavuorii sp. nov. (Vietnam), S. nigra sp. nov. (Indonesia: Java), S. quadriloba sp. nov. (Indonesia: Sumatra), S. sadongensis sp. nov. (type-species) (Malaysia: Sadong) and S. sarawakensis sp. nov. (Malaysia: Borneo: Sarawak) The following new combinations are proposed: Anaceratagallia srinagarensis (Kameswara Rao & Ramakrishnan) comb. nov. (Agallia), Hemagallia biplagiata (Melichar) comb. nov. (Agallia), Hemagallia plotina (Distant) comb. nov. (Agallia), Ianagallia bifurcata (Sawai Singh & Gill) comb. nov. (Austroagallia), Igerna atrovenosa (Melichar) comb. nov. (Agallia), Igerna fasciata (Osborn) comb. nov. (Agalliopsis), Igerna quadrinotata (Melichar) comb. nov. (Agallia), Igerna nigrita (Melichar) comb. nov. (Oncopsis) and Igerna violacea (Distant) comb. nov. (Nehela). The following species are treated as new synonyms: Agallia pseudorobusta Kameswara Rao & Ramakrishnan syn. nov. of Anaceratagallia cuspidata Dlabola; Anaceratagallia delhiensis Kameswara Rao & Ramakrishnan syn. nov. of Anaceratagallia robusta Pruthi; Agallia campbelli Distant syn. nov. and Agallia janaka Distant syn. nov. of Hemagallia biplagiata (Melichar); Agallia rugosa Distant syn. nov. and Agallia bhuntra Sawai Singh syn. nov. of Hemagallia plotina (Distant), Austroagallia bisinuata Viraktamath & Viraktamath syn. nov. of Igerna quadrinotata (Melichar), and Dryodurgades bifurcatus Cai & Shen syn. nov. of Dryodurgades formosana (Matsumura). Most of these taxa are described and illustrated. Keys to genera and species are also included. Copyright © 2011 . Magnolia Press.
Kumaraswamy S.,Indian Institute of Science |
Kumaraswamy S.,University of Agricultural Sciences, Bangalore |
Kunte K.,Tata Institute of Fundamental Research
Biodiversity and Conservation | Year: 2013
To achieve food security and meet the demands of the ever-growing human populations, farming systems have assumed unsustainable practices to produce more from a finite land area. This has been cause for concern mainly due to the often-irreversible damage done to the otherwise productive agricultural landscapes. Agro-ecology is proclaimed to be deteriorating due to eroding integrity of connected ecological mosaics and vulnerability to climate change. This has contributed to declining species diversity, loss of buffer vegetation, fragmentation of habitats, and loss of natural pollinators or predators, which eventually leads to decline in ecosystem services. Currently, a hierarchy of conservation initiatives is being considered to restore ecological integrity of agricultural landscapes. However, the challenge of identifying a suitable conservation strategy is a daunting task in view of socio-ecological factors that may constrain the choice of available strategies. One way to mitigate this situation and integrate biodiversity with agricultural landscapes is to implement offset mechanisms, which are compensatory and balancing approaches to restore the ecological health and function of an ecosystem. This needs to be tailored to the history of location specific agricultural practices, and the social, ecological and environmental conditions. The offset mechanisms can complement other initiatives through which farmers are insured against landscape-level risks such as droughts, fire and floods. For countries in the developing world with significant biodiversity and extensive agriculture, we should promote a comprehensive model of sustainable agricultural landscapes and ecosystem services, replicable at landscape to regional scales. Arguably, the model can be a potential option to sustain the integrity of biodiversity mosaic in agricultural landscapes. © 2013 Springer Science+Business Media Dordrecht.