The present study is to understand the intrinsic ecological trait of invasive plant Senna alata relating to soil characteristics and seasonality distributed in the Puducherry region located under tropical climate. Plant biomass, soil parameters linked with soil enzyme activities are examined in six sites where S. alata is found growing. From the study, it is demonstrated that invasive species S. alata exhibits heterogeneity in invaded soil characteristics but variation in aboveground biomass (AGB) of S. aalata is not significant. Soil moisture and soil enzymes activities and AGB are significantly positively correlated whereas pH and EC negatively correlated. Seasonal variation in total nitrogen, phosphorus, and elements viz. Mg, Ca, and Na is inconsistent in their seasonality. Based on observations made and results obtained in the study, it is stated soil characteristics and their seasonality in the S. alata invaded soil is, site-specific resulting in heterogeneity; but such heterogeneity is not exhibited in AGB in six sites and it is, therefore, reported that such an idiosyncratic trait of S. alata is one of the potential traits influencing successful invasion by S. alata as mono-species population. The statistical analyses also confirmed the observation made. The outcome of the study would help to prepare management programmes to check spreading of invasive species so as to restore native plant diversity in and around Puducherry region.

An attempt is made to examine prevalence of insect pests and their seasonality in Senna alata L. from Puducherry region, India covering a period of one year. Totally, five insects found to make use of S. alata for ovideposition viz. butterfly (Catopsilia pyranthe), Jewel bug (potamid Chrysocoris stollii), flower bud worm (Hendecasis duplifascialis) Aphides (Aphis sp.), and Mealy bugs. All egg masses collected from leaves and flower buds are reared and developmental stages are documented. Secondly, two virulent borers viz. flower bud borer H. duplifascialis and pod borer Etiella zinckenella and their developmental stages are also documented for the first time in S. alata; thirdly, the extent of caterpillars that destroy medicinally important leaves of S. alata mostly young leaves, has also been documented. Adult insects viz. aphides (Aphis sp.) and green stink bug Acrosternum hilare, are also found feeding on leaves of S. alata. The last but unique observation made during field study is sighting of a worm inside anther for the first time. The seasonal study revealed that ovideposition is influenced by temperature and rainfall and showed higher level of ovideposition during late post-monsoon and early summer. The overall picture on association of insect pest with S. alata indicated a low level of insect pest faunal diversity. Present report would be considered as the important input into the annals of medicinally important member of the genus Senna.

Present investigation is focused on fungal infection and consequent disease prevalence in a commercially important plant Cassia alata L., profusely growing in and around Pondicherry region covering four seasons in 2015. Observation and collection of infected leaves, flower buds and pods are done monthly infected leaves and flower buds are subject to culture adopting suitable methods. The common fungal diseases recorded in leaves of C. alata are leaf spot disease and Anthracnose and fungal species namely slimy Aureobasidium, two species of Aspergillus, Rhizopus sp. Alternaria sp. are recorded from these infected plant parts. One of the important results obtained from the present study is that cut ends of the leaves made by folivory insects are found to be infected by the fungi whereas the cut ends of the leaves left by caterpillars are not infected. Relevant photographs in support of fungal disease are also given. The report includes information on the progress of leaf spot and Anthracnose in leaves-stage with photographs which is considered as an important useful input for commercial cultivators in disease management. The uniqueness/ highlight of this work includes one interesting observation that the cut ends of the leaves left by the caterpillars are not infected with fungal species even under ambient climate. This opens up a new avenue in the field of bioactive compounds from caterpillars particularly of the migrant butterfly, Catopsilia pyranthe. Taxonomic authentication of the host plant Cassia alata is also done by the molecular method and obtained NCBI Accession number after submitting sequences.

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