Southern Peninsular Research Articles

Occurrence and Management of Blast and Leaf Blight in Browntop Millet [Brachiaria ramosa (L.) Stapf

Brown top millet is an underutilized millet crop and grown in Southern Peninsular region of India. Blast as well as leaf blight diseases are frequently noticed in Browntop millet. A study was carried to find out the seasonal occurrence and management of major diseases of the crop at Centre of Excellence in Millets, Athiyandal during 2022-23 and 2023-24. The crop was sown during Second week of July of both years and the blast symptom noticed from 10 days after sowing (DAS) and shows increasing trend upto 40 DAS and later shows decreasing trend till the maturity of the crop. However, the leaf blight noticed from 20 DAS and reached maximum level at 60 DAS in both years. Field experiments were conducted to study the effect of biocontrol agents and fungicides on incidence of blast as well as leaf blight in browntop millet. The results show significant variation observed between the treatments on the disease incidences in both the years. Seed treatment with B. subtilis @10g/kg of seed +Foliar spray of Azoxystrobin 23% SC @ 1ml/l at 20 and 40 DASrecorded the lower incidence of blast as well as leaf blight disease incidence and produced more grain yield when compared to other treatments.

Estimation of Groundwater Drought Propagation in the Selected Districts of Palar River Basin, Southern Peninsular India

Estimation of Groundwater Drought Propagation in the Selected Districts of Palar River Basin, Southern Peninsular India

Correction to: Evaluating the Influence of El Nino–Southern Oscillation (ENSO) Patterns on the Spatio-Temporal Variations of Drought over Southern Peninsular Indian Region

Correction to: Evaluating the Influence of El Nino–Southern Oscillation (ENSO) Patterns on the Spatio-Temporal Variations of Drought over Southern Peninsular Indian Region

Diversity of Wild Gingers (Zingiberaceae) in Southern Peninsular Malaysia: Panti Forest Reserve and Labis Forest Reserve

Family Zingiberaceae is well distributed in Peninsular Malaysia, including the southern region of Johor. A preliminary survey updated the current checklist of wild gingers from Panti Forest Reserve and Labis Forest Reserve. During the brief survey, 28 taxa from 8 genera were recorded. The genera include Amomum, Alpinia, Boesenbergia, Conamomum, Etlingera, Globba, Hornstedtia, Meistera, Scaphochlamys, Sundamomum, and Zingiber malaysianum. Three endemic species to Johor were recorded from the study sites: Scaphochlamys lanceolata, Scaphochlamys klossii var. glomerata, and Zingiber.

Barcoding Mullets (Mugilidae): Genetic Characterization of Exploited Species in Southern Peninsular India

Fishes of the Mugilidae family are poorly known from a taxonomic perspective, largely because of their conservative morphology. In this paper, we aim to fill the knowledge gap and data deficiency regarding the genetic diversity of mullets occurring in southern peninsular India. A comprehensive mitochondrial phylogeny based on 238 COI sequences (78 newly generated) and three species delimitation methods (ASAP, RESL, and ABGD) confirmed the presence of 21 species of mullets within eight genera in southern peninsular India. These include one species each under the genera Rhinomugil Gill 1863, Minimugil Durand, Chen, Shen, Fu, and Borsa, 2012, Plicomugil Schultz 1953, and Ellochelon Whitley 1930; seven species of Planiliza Whitley 1945; four species of Crenimugil Schultz 1946; four species of Osteomugil Luther 1982; and two species of the “Mugil cephalus Linnaeus 1758” complex—though with uncertainty regarding the exact geographic origin of one of the two species of the “Mugil cephalus” complex and one species phylogenetically close to Planiliza subviridis (Valenciennes 1836). We provide an overview of the specific geographical regions in southern peninsular India, and “species groups”, which require future research using an integrative approach, so as to unravel the true extent of mullet diversity and their distribution in the region.

Relationship fecundity – morphometrics in the green tiger shrimp, Penaeus semisulcatus De Haan, 1844 (Decapoda, Penaeidae), along the Palk Bay, southern Peninsular India

Abstract The green tiger shrimp, Penaeus semisulcatus, is a commercial species supporting important fishery along the Palk Bay coasts. It is a much sought-after seafood commodity influencing the livelihood of the local fishers. This study aims to investigate the fecundity of the species in relation to its morphometry. Fecundity is an index of reproductive capacity used to calculate a stock’s reproductive potential and the egg’s survival. The absolute fecundity of the shrimp ranged from 26 100 to 750 000 ova alive per female, and the mean absolute fecundity from 59 100 to 583 000 ova alive per female. The relationship between fecundity and the morphometric measurements showed a positive exponential correlation. One-way ANOVA indicated a significant difference in the different size classes’ carapace length, total weight, ovary weight, absolute fecundity, stomach weight, and gastrosomatic index. There was no significant difference between the relative fecundity and the gonadosomatic index. This study provides insight into the reproductive potential of P. semisulcatus for efficient management of the resource in Palk Bay, Tamil Nadu, India.

Paleo–Mesoarchean sedimentary record in the Dharwar Craton, India: Implications for Archean ocean oxygenation

The early Archean oceans were marked by significant redox changes which have subsequently shaped the Earth’s biosphere. Archean chemical sediments of banded Iron and Manganese formations provide important geochemical proxies for these historical shifts in the redox conditions and to trace the ancient sedimentation patterns and protoliths. In this study, we investigate the proto-ore of the Archean Mn-formations of the Sandur, Chitradurga and Shimoga greenstone belts of Dharwar Craton of southern Peninsular India, which is geochemically characterised as quartz arenites, Mn-arenites, Fe-arenites, Mn-argillites and Fe-argillites. The geochemical systematics suggest their deposition in shallow to deeper shelf in the Archean proto-ocean. The detrital zircon U-Pb systematics of Mn arenites and argillites indicate their maximum depositional age of 3230 ± 52 Ma representing the oldest onset of sedimentation during the Paleo–Mesoarchean timeframe in the Chitradurga Group of Dharwar Supergroup. The detrital influx proxies suggest variations in sedimentation rates associated with the Archean transgressive–regressive cycles and fluctuating hydrodynamic conditions, together reflecting an increasing trend in the contributions of recycled sediment from Sandur to Chitradurga and Shimoga greenstone belts. The available detrital zircon ages of the Mn arenites and argillites from these greenstone belts indicate a ∼ 600 Ma prolonged period of Mn deposition for which high-T hydrothermal fluids from Archean mid-oceanic ridges supplied the manganese. The trace element compositions of the concordant detrital zircons suggest 3.3–3.1 Ga Dharwar basement TTG/granitoid source which is corroborated by the zircon crystallization temperatures of 690–820 °C. The source-normalised α-dose rates of the detrital zircons signify greater degrees of sediment transport and multi-cycle nature which correspond to the earliest episode of crustal growth in the Indian sub-continent associated with the Mesoarchean Ur supercontinent. The clastic-chemogenic sedimentation attained through concomitant detrital sediment–seawater-metalliferous hydrothermal fluid mixing at an epicontinental passive margin resulted in the deposition of Mn-arenites and argillites closer to the higher Eh shore, while the Fe-rich sediments formed at a relatively deeper shelf characterised by comparatively lower Eh and more alkaline conditions. The comprehensive geochemical and geochronological data of the Archean Mn arenite-argillite sequences reveal the significance of regional episodes of ocean oxygenation at the shallow shelves of Archean oceans prior to great oxygenation event (GOE) that was mediated by the prolific growth of ancient microbiota which transformed the Earth to a more habitable planet.

A Note on New Records of Ferns at Ayer Hitam Forest Reserve, Johor, Malaysia

On a scientific expedition to Ayer Hitam Forest Reserve at Muar, Johor, Malaysia, 71 fern species belonging to 16 families and 25 genera were collected and identified. Fifty-one of the ferns are native to Peninsular Malaysia while the remaining 20 are non-native. Five newly recorded fern species in Johor, Southern Peninsular Malaysia, namely Angiopteris helferiana, Lindsaea trichomanoides, Lomariopsis brackenridgei, Pteris umbrosa and Pteris cretica were briefly described.

Megalithic Cemeteries and Land Use in the Yān Oya River Basin of Sri Lanka

Megalithism is a cultural phenomenon associated with mortuary rituals. Societies that practise megalithism construct burials and memorials using stone slabs in memory of the dead as a form of ancestor worship. Archaeological evidence shows that the remains of these cultural practices that originated during the Neolithic period, occur in various geographical zones around the globe. Across peninsular southern India and Sri Lanka megalithism is observed, reflecting the cultural identity of Early Protohistoric-Iron Age communities of South Asia and practised even today, in certain parts of India. In Sri Lanka, the Yān Oya macro region of the North Central Dry plains is a geographical region where megalithism is prevalent and visible on the landscape. Megalithic groups appear to have widely dispersed across the Yān Oya river basin from the early quarter of the 1st millennium BCE to the early quarter of the 1st millennium CE with their adaptive strategy contributing to the formation of the cultural landscape of the region. In this paper, the megalithic cultural complex in the Yān Oya macroregion is discussed using evidence from archaeological surveys and excavations, with a focus on territorial expansion, resource exploitation and land use pattern. Archaeological evidence points to a series of three patterns or phases where the megalithic community in the region developed from a nomadic or semi nomadic pastoral subsistence to a sedentary village based agro-pastoral subsistence.

Assessment of Reliability, Resilience, and Vulnerability (RRV) of terrestrial water storage using Gravity Recovery and Climate Experiment (GRACE) for Indian river basins

Understanding the changes in water storage of a certain region is crucial for planning and managing water resources since it is inevitable due to climate change and anthropogenic activities. Sustainability analysis using Reliability, Resilience, and Vulnerability (RRV) approch give an idea about the exploitation of the water resources, steps taken to restore the water storage, and how sustainable the overall water resources are with changing climate and anthropogenic influence. To determine the sustainability of water resources in a region, extensive data of different hydrological variables above, below, and on the earth's surface are required. But, the data for those hydrological variables are difficult to get and not available at all sites. The Terrestrial water storgae (TWS) data of Gravity Recovery and Climate Experiment (GRACE) has some benefits in this regard, as it provides a column integrated data representing groundwater, soil moisture, surface runoff, and snowmelt. This study presented the sustainability analysis of the TWS using the Reliability-Resiliency-Vulnerability (RRV) assessment over the Indian River basins. The GRACE-based index is presented to define the deficit (or excess) of the TWS over an area. The RRV assessment helps to find the frequency of satisfactory water storage (reliability), the capacity to recover from the water storage deficit (resilience), and the magnitude of the extreme deficit (vulnerability) of TWS. The spatial distribution of sustainability is analyzed by combining the Reliability, Resiliency, and Vulnerability of TWS. The results of the GRACE's TWS-based sustainability analysis are validated with the individual hydrological variables of the Global Land Data Assimilation System (GLDAS) and in-situ groundwater observations. The study demonstrated the applicability of the GRACE's TWS data for analyzing the sustainability of water resources across different River basins in India, and found that there is a decreasing trend of groundwater storage in Punjab and Haryana, an increasing trend of snowmelt in the Himalayas, and decreasing trend of surface runoff in the Southern peninsular, which indicates the overall water availability across the country is decreasing.

Evaluating the Influence of El Nino–Southern Oscillation (ENSO) Patterns on the Spatio-Temporal Variations of Drought over Southern Peninsular Indian Region

Evaluating the Influence of El Nino–Southern Oscillation (ENSO) Patterns on the Spatio-Temporal Variations of Drought over Southern Peninsular Indian Region

Assessing the Morphological Quality of the Calore River (Southern Italy)

As highlighted by the EU Water Framework Directive from 2000, the hydromorphology of a stream, besides water quality and biological aspects, is one of the main elements to be evaluated to correctly assess its ecological state. Notwithstanding this, there are no such studies in peninsular Southern Italy. This study provides a contribution to filling this gap by assessing the morphological quality of one of the major rivers of this area, i.e., the Calore River, by using the IDRAIM method. The latter presents the advantage of taking into account the specific Italian context in terms of channel adjustments and human pressures, together with pre-existing geomorphological approaches developed in other countries. The method is based on data obtained by means of GIS analysis, remote sensing, and field survey. The analysis provided encouraging results, highlighting the good morphological quality of the Calore River. To maintain such quality, accurate monitoring of the human activities and/or careful planning of structures that could negatively affect the river’s morphological quality is unquestionably needed. The Calore River morphological quality seems to be controlled by artificiality rather than by the channel changes experienced since the 1950s. The results will be fundamental for already planned studies dealing with flood hazard and risk assessment.

Characterization of Mungbean yellow mosaic India virus genome with a recombinant DNA-B in Southern Peninsular India.

Mungbean yellow mosaic India virus (MYMIV) is a representative of the genus begomovirus/Begomoviridae, which is prevalent in the northern part of Indian subcontinent causing yellow mosaic disease (YMD). This virus is rapidly evolving and breaking the resistance in the advanced lines causing huge economic losses in the pulse production. In this context, the present investigation on characterization of the causal organism of YMD was undertaken METHODS AND RESULTS: A novel recombinant isolate (YMV-BG-BPT) causing YMD was identified from blackgram in Andhra Pradesh, southern peninsular region of India. The association of a bipartite begomovirus with the disease was done by sequence analyses of the cloned full-length genome. The full length genome sequences were submitted in NCBI GenBank with accession numbers MZ235792 (DNA-A) and MZ356197 (DNA-B). The sequence analysis of DNA-A of YMV-BG-BPT showed maximum of 99.12% similarity at nucleotide level with Mungbean yellow mosaic India virus (MYMIV) isolate reported from Tamil Nadu (KC911719), India which is also confirmed by clustering pattern in phylogenic analysis and DNA-B showed 95.79% with Mungbean yellow mosaic virus (MYMV) isolate reported from Tamil Nadu (KP319016) and 95.05% with MYMIV isolate reported from Karnataka (MT027037). The huge variation in DNA-B lead us to suspect a recombination in DNA-B, where a recombination event in the CR, region coding for nuclear shuttle protein and movement protein of DNA B was detected in which MYMV-BG-AP-IND (KF928962) and MYMIV-GG-CH-IND (MN020536) have been identified as major and minor parents, respectively. Overall, the present study revealed occurrence of MYMIV with recombinant DNA B component in southern peneinsular India.

The Enigma of Mehri and Southern Peninsular Arabic Existential śī and šī

Abstract The Modern South Arabian languages and the many varieties of Arabic share in the functions of a particle, realised in the largest extant MSA language, Mehri, as si and variously in Arabic as šay(y), še, ši and ši. In the Modern South Arabian languages and in the Arabic varieties of southern Arabian Peninsula, si and reflexes of ši serve as existential particles with a meaning analogous to English ‘there is/was’. The doublet si/ši also performs other grammatical operations in both sets of languages, functioning as partitives, polar interrogatives and as expressing the various meanings of ‘thing’. This similarity of form and function in Arabic and MSA suggests borrowing from one language to the other, although shared inheritance cannot be discounted completely. The assumption about Arabic reflexes of ši is that their grammatical functions derive originally from that word for ‘thing’ (of which there are others in both languages). Similarly, the assumption has been that MSA si is borrowed from the same Arabic word. Nevertheless, the analogous usages between Mehri and Arabic give cause to reassess such assumptions, leading to the opposite conclusion: The borrowing proceeded from MSA to Arabic and the substantive meaning is the end form, not the origin.

Regional modulating behavior of Indian summer monsoon rainfall in context of spatio-temporal variation of drought and flood events

In this paper, daily modulating behaviors of Indian summer monsoon rainfall (ISMR) has been evaluated over eight important sub-zones of India viz Northwest India (NWI); Northcentral India (NCI); West Peninsular India (WPI); Eastern Peninsular India (EPI); Southern Peninsular India (SoPI); Central India (CI), Northeast India (NEI) and Western Ghat (WG) using latest SA-CORDEX simulated climate data during 1981–2015. The climate extreme indices, standardized precipitation index (SPI) and empirical orthogonal function (EOF) have been utilized to uncover substantial regional spatial patterns and temporal variability of monsoon precipitation over India and its sub regions to understand the regional modulation of these events based on duration, frequency and severity. The comprehensive assessment of ISMR modulated characteristics (intensity, spell, and frequency) were showing significant decreasing trend over NEI and NCI which can be leading factors for demarcating major hotspots for land degradation, effective management and adaptation towards water resources and hazards related to the flood/drought events. India has received flood events (1983, 1988, 1994, 2005, 2011, 2013) and drought event (1982, 1987, 2002, 2004 and 2009) during 1981–2015, which have been verified with SA-CORDEX RCMs (RegCM4.7, COSMO & REMO2015) using SPI. The first mode of EOF(IMD), explained 17% of the total SPI variability on the interannual scale, shows anomalous large positive values concentrated over the western peninsular region and extending towards central India as well as the NWI region of India. On the other hand, high anomalous negative values dominated over the NEI and eastern parts of the Indo-Gangetic Plain. Therefore, this study underscores the importance to uncover the prevalent dynamics and climate change variability on changing trend variability of the precipitation indices, drought and flood characteristics. As moderate to severe drought variability portrays a diversity over regional scale viz northwest India, north central India, eastern ghat of the southern peninsular region and northeast India while the occurrence of moderate to severe flood are dominated towards Himalaya region (26°N-35°N; 70°E-80°E), western peninsular region and western ghat.

A tale of bifaces from southern peninsular India (British Museum and Musée de l'Homme collections): a geometric morphometric and classical approach

Bifacial tools (especially handaxes and cleavers) have played an important role in the Lower Palaeolithic studies trying to decode Acheulean lifeways through them. The methodological approach based on classical metrical analysis, could be insufficient and often subjective, especially in instances of asymmetrical tools, and incorrect orientation for capturing the morphological data. Recent years have seen the application of geometric morphometric methods on lithic tools (2D contours and 3D volumetric forms) as an accurate, efficient and objective method of data collection. This alternative approach has the additional advantage of being both interactive and reversible analytic process, reducing the time and effort in collection of data. Traditionally the museum collections of Palaeolithic artefacts of old surveys and fieldworks, are seldom subject to study due to their incomplete and often doubtful or mixed context. In the current study, both geometric morphometric on 2D contour analysis as well as classical techno-typological analytical methods has been applied to bifaces from Southern Peninsular Indian Palaeolithic kept in the British Museum (London, UK) and Musée de l’Homme (Paris, France). The aim of this study is to highlight the complementary nature of both analytical methods in deciphering and throwing light on the patterns of bifaces (handaxes and cleavers), their technological variability and stability and to identify if there are regional technological trends. The results obtained from both classical analysis and geometric morphometric analysis allow to show that handaxes were highly variable in both the regions while the cleavers show high standardization. While the former approach throws light on the knapping techniques and preferences, the latter complement the results with the shape preferences and variations across regions.

Holocene Monsoonal Variations Over Southern India: Looking Into Its Antecedents

A proper understanding of the paleoclimatic variability in the Southern Peninsular India demands a high-resolution paleoclimate reconstruction record. Hence, in this paper, we compiled all the available paleoclimate records from various locations across the Southern India that receives the southwest and the northeast monsoon. We delineated the southwest monsoon (SWMR) and Northeast monsoon (NEMR) variations within the Holocene Period based on the existing paleoclimatic record from this region. Paleoclimate records are primarily based on various paleoclimate archives and proxies. A detailed study of these variations unravels, (i) that SWMR gradually intensified since the younger dryas during the Early Holocene period. On the contrary, NEMR records indicate a dry phase during the same period. (ii) During the mid-late Holocene, precipitation in SWMR-dominated regions decreased, whereas precipitation in NEMR-dominated regions shows an increasing trend. (iii) Then, in the late Holocene Period, SWMR exhibits an overall wet phase with a few drier periods, and NEMR shows an intense dry period with shorter wet phases, which can be correlated to the demise of Chola dynasty, in the Southern India.

Peninsular southern Europe refugia during the Middle Palaeolithic: an introduction

ABSTRACTNeanderthals faced great environmental and climatic instability during the Pleistocene, which may have influenced their lithic technology, subsistence patterns, mobility, behaviour and survival. Modern research assessing the effect of climate and environment on the Middle Palaeolithic and transition to the Upper Palaeolithic has often turned to southern Europe, specifically peninsular southern Europe (Iberia, Italy and the Balkans). These are regions typically regarded as refugia during periods of unfavourable climatic conditions, inspiring hundreds of palaeoenvironmental studies at Neanderthal sites and hypotheses on late Neanderthal survival in locations with relative ameliorated conditions. Here, we present the topic of the special issue focusing on peninsular southern Europe refugia during the Middle Palaeolithic covering the three main peninsulas. Its 16 contributions discuss relevant data on peninsular southern Europe as possible refugia during periods of unfavourable climate during the Middle Palaeolithic and transition to Upper Palaeolithic.

Source Parameters of Shallow Microtremors Induced by Seasonal Groundwater Recharge in Hyderabad, Southern Peninsular India

Abstract Source parameters were estimated using multiple empirical Green’s functions (meGf) method for 2 clusters of shallow depth and small-magnitude earthquakes induced by the infiltration due to gravity into the groundwater zone after heavy monsoons during October 1998 and October 2017, in Hyderabad, South India. First, four decades of earthquake catalogue data recorded by HYB seismic station at CSIR-National Geophysical Research Institute (NGRI) was used to characterize the spatiotemporal variation in seismicity. Enhanced seismicity was noticed because of the strong seasonal fluctuations of the groundwater table during the post-monsoon season. Second, focus was on the estimation of source parameters for two cluster of swarm events whose local magnitude (Ml) are in -0.09<Ml<1.52 range. Stress drops (<1Mpa) was observed in correlation with the seismic moment for both earthquakes sequence. The results indicate that the difference in corner frequency between the two swarm sequences is more than a factor of two, which results in a difference of more than an order of magnitude in the stress drop and seismic moment. The spatial migration of micro-earthquakes is most striking feature observed in both series of microearthquakes because of the diffusion of fluids. Groundwater level response in post monsoon have a significant effect in triggering the earthquakes during the observed time period. The spectrograms are estimated to understand the mechanism of sounds generated by the events with shallow hypocentres during 2017 swarm activity. Spectrogram analysis of the events revealed high energy at frequencies ≥20 Hz. In addition, the particle motion was dominated by retrograde elliptical motion consistent with Rayleigh waves at higher frequencies. This study of source parameter characterization of swarm activity may provide additional information about induced seismicity for seasonal fluctuations.

Magmatic and metamorphic evolution of a layered gabbro-anorthosite complex from the Coorg Block, southern India: Implications for Mesoarchean suprasubduction zone process

As one of the oldest crustal blocks in Southern Peninsular India, the Coorg Block has been the focus of investigations related to crustal evolution in the early history of the Earth with implications on Mesoarchean plate tectonic processes. The Coorg Block is dominantly composed of arc magmatic rocks and bordered on the north by the Mercara Suture Zone, a Mesoproterozoic subduction-collision zone hosting extruded high-pressure and ultra-high temperature metapelitic and meta-mafic rocks. Here, we report the occurrence of a dismembered gabbro-anorthosite complex corresponding to a layered intrusion from the northern margin of the Coorg Block. We present results from an integrated study on the petrology, mineral chemistry, P-T phase equilibria, whole-rock geochemistry, and zircon and monazite U–Pb geochronology to understand the magmatic and metamorphic evolution of the layered intrusion and associated rocks. The geochemical data suggest that the parental magma was generated within a suprasubduction zone setting. Phase equilibrium modelling of garnet-bearing metagabbro from the Coorg Block suggests metamorphic P–T range of 10.5–11 kbar at 1000–1100 °C corresponding to ultra-high temperature conditions. The zircon U-Pb data from the various rock types of the mafic–ultramafic suite yield weighted mean ages at 3176 Ma, 3174 Ma, 3143 Ma, and 3124 Ma whereas the associated charnockite shows a slightly older age of 3319 ± 12 Ma. Metamorphic zircon from charnockite yield an age of 3101 Ma, close to the monazite age of 3110 ± 24 Ma from the same rock, constraining the timing of metamorphism as Mesoarchean, and marking the collisional event between the Coorg Block and the Dharwar Craton along the Mercara Suture Zone. We propose a tectonic model involving southward subduction of the Western Dharwar Block beneath the northern margin of the Coorg Block that can explain the extensive arc magmatism and suprasubduction zone rock suites, followed by ocean closure and collision along the Mercara Suture Zone, accompanied by high P-T metamorphism.