Pesticide residues in Indian spices Thomas Biju Mathew, Thania Sara Varghese, V. Vijayasree, K. Pallavi Nair, P. R. Nithya, S. M. Seena Handbook of Spices in India 75 Years of Research and Development, 2024
Crop Wild Relatives of Pea (Pisum sativum) for Designing Future Climate-Resilient Cultivars R. Beena, P.R. Nithya, Roshni Vijayan Legume Crop Wild Relatives their Role in Improving Climate Resilient Legumes, 2024 Pisum, commonly known as peas, encompasses wild relatives with valuable genetic traits, including resistance to pests and pathogens. Pea, Pisum sativum L. (2n = 2x = 14), belonging to the Leguminosae (Fabaceae) family, is a widely grown vegetable rich in protein, amino acids, and carbohydrates. Peas are consumed alone or mixed with other vegetables and processed for freezing, canning, and dehydration. Originating from Central Asia, the Near East, Ethiopia, and the Mediterranean, they are annual herbaceous plants with racemose inflorescences. They produce single to multiple pods, each containing five to ten seeds. The six species are Pisum sativum (garden pea), P. elatius (Mediterranean pea), P. arvense (field pea), P. abyssinicum (Abyssinian pea), P. humile (dwarf pea), and P. fulvum (red yellow pea). Pea crops are susceptible to fungal, bacterial, and viral diseases. Efforts are made to identify resistance sources and genes. This chapter explores the potential of wild pea varieties for resistance in crop improvement programs, discussing the significant stresses affecting pea crops, and methods to transfer desirable traits from wild to cultivated varieties, emphasizing resistance to pathogens, insects, and nematodes. We also consider the prospects of harnessing wild pea germplasm for sustainable pea production.
Comparative study of the ditrophic interaction between Beauveria bassiana and Plutella xylostella P. R. Nithya, S. Manimegalai, S. Nakkeeran, S. Mohankumar 3 Biotech, 2021 In the present investigation, hyperparasitic interaction between B. bassiana, TM (MH590235) and P. xylostella was studied through scanning electron microscopy and chromatographic techniques. Dose–mortality responses showed an increase in mortality of larva with an increase in spore concentration. The LC50 value for B. bassiana isolate TM (MH590235) was 2.4 × 107 spores mL−1. The ditrophic interaction between B. bassiana and P. xylostella after 24 h revealed the adherence of conidia on stemmata, sensory setae, maxillary palpi and legs. After 48 h post-infection (hpi), germination of the conidia and appressorium formation was observed. Formation of hyphae and initiation of fungal networking was observed at 72 hpi. Complete ramification by mycelia and conidiogenesis of B. bassiana was observed over the mycosed cadaver after 168 hpi. Subsequently, typical sympodial conidiophores of B. bassiana bearing secondary spores were also observed. The metabolome profile of healthy larvae of P. xylostella revealed the presence of non-volatile organic compounds (NVOCs) like docosene, nonadecene, palmitic acid and heneicosane. However, the NVOC profile was different in the P. xylostella larvae hyperparasitized by B. bassiana. The metabolites present in the infected cadaver were phthalate esters, hydroxyquebrachamine and lactones.
In vitro efficacy of beauveria bassiana (Balsamo) vuillemin against tetranychus urticae koch on tuberose S. Athisintha, S. Manimegalai, P. Nithya, R. Muthulakshmi Journal of Biological Control, 2021 Bio efficacy of virulent isolate of entomopathogenic fungi, Beauveria bassiana (MK918495) was evaluated against two spotted spider mite, Tetranychus urticae on tuberose under pot culture condition at Insectary, Department of Agricultural Entomology, TNAU, Coimbatore. For effective working of any insect pathogen, it is mandatory to develop an effective formulation. Keeping this point in view, in the present study, compatibility of the fungal isolate with two different oils, viz., ground nut and sunflower were tested at different concentrations, viz., 1, 3, 5 and 10%. The results revealed that the groundnut oil was compatible with B. bassiana at all concentrations with respect to colony growth and spore yield compared to sunflower oil which was compatible only at one percent. Based on the results, oil in water and oil based formulations were prepared. At higher concentration of 10%, groundnut oil recorded the radial colony growth of 36.90 mm diameter and spore yield of 1.2 x 10 8 spores mL -1 . Among the seven formulations (A-G) tested, formulation D which contained surfactant mixture having HLB value of 10.00 (53.33% Tween 80 and 46.67% Span 80) formed a better suspension with less flocculation layer and dispersion of conidia in spray fluid and was found to be better as it formed a good emulsion with water by mere shaking. Results of pot culture studies revealed that groundnut oil based fungal formulation was effective with a cumulative mean mite population reduction of 64.98% followed by crude fungal spore suspension (62.16%) and both were statistically on par with each other. Standard chemical check, Fenazaquin 10% EC @ 1.5 mL L -1 recorded significantly highest population reduction of mites (77.20%).Â
Enriched bioformulations of Lecanicillium lecanii (Zimmermann) Zare and Gams against sucking pests of yard long bean, Vigna ungiculata L. Walp sesquipedalis P.R. Nithya, O.P. Reji Rani Journal of Entomological Research, 2019 The formulations were sprayed at two levels of infestation of the major sucking pest, the black pea aphid, Aphis craccivora Koch, first at 5% (vegetative phase) and second at 50% (reproductive phase). The experiment was laid out in randomized block design with six treatments (1-untreated control) and four replications. The treatments comprised the following (i) Formulation I-chitin enriched groundnut oil (CGNO) + Adjuvant combination (AC) 1 + boric acid (BA) 1% (ii) Formulation II-CGNO + AC 2 + BA 1% (iii) Formulation III-CGNO + AC 3 + BA 1% (iv) Talc based KAU product of Lecanicillium lecanii (v) chlorpyriphos 0.05% as chemical check and (vi) untreated control. Analysis of the data on population revealed that plots treated with Formulation I was equally effective as chlorpyriphos 0.05% resulting in 98.93% control at 5% level of infestation and 96.74% at 50% level of infestation levels of aphids, seven days after spraying (DAS). The percentage reduction noted in population of mites, jassids and whiteflies was 92.58, 58.81 and 96.74%, respectively at seven DAS. The yield recorded with Formulation I and II was 10.98 t/ha and 10.53 t/ha respectively, which were on par with the chemical check.
Metabolome heterogeneity in the isolates of entomopathogenic fungus, Beauveria bassiana (Balsamo) Vuillemin P.R. NITHYA, S. MANIMEGALAI, S. NAKKEERAN, S. MOHANKUMAR, S.JAYARAJAN NELSON, , , , , and Journal of Biological Control, 2019 Entomopathogenic fungi are known to produce a multitude of low molecular weight secondary metabolites involved in different biological processes including fungal development, intercellular communication and interaction with other organisms in complex niches. In the present investigation, heterogeneity in metabolome profile of three isolates of Beauveria bassiana viz., MH590235 (TM), MK918495 (BR) and KX263275 (BbI8) were analyzed through GC-MS. Distinct differences in metabolite profile of the isolates were observed. A total of 63 metabolites were detected from all the isolates combined. Metabolites, 5-Oxotetrahydrofuran-2-carboxylic acid and undecane were found to be specific to BR isolate. Macrocyclic gamma lactones were detected in culture filtrates of BR and BbI8, oleic acid and hexadecanoic acid in TM and BR. An insecticidal compound, levoglucos an was detected in all the fungal isolates. Among the isolates, TM revealed higher variability in the metabolite production through PCA analysis. The metabolome of TM isolate contained compounds having several biological functions, viz., insecticidal and antimicrobial activity, lipid and fatty acid metabolisms and virulence enhancing factors.
