School Of Environment And Earth Sciences

Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/83

Browse

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Effect of arsenic on the growth and physiology of triticum aestivum L. seedings
    (Central University of Punjab, 2012) Nag, Shilpa; Mittal, Sunil
    The effects of Arsenic (As) were investigated on four varieties of T. aestivum viz. PBW 343, PBW 550, PBW 621 and HD 2967 to elucidate the toxicity of As on morphological, physiological, biochemical and antioxidant processes of plant in early stage. The results showed that seed germination, root length, shoot length and biomass decreased gradually with increase in concentrations of As (125-750'M) and this decrease was biologically significant. The photosynthetic and respiratory activity of the test plants was also investigated. The decrease in chlorophyll and carotenoids content with increase in As content indicates negative effect of As on the photosynthetic pigments. However, the total cellular respiration increased with increase in As concentration and this probably may be due to the enhancement in respiratory enzymes which leads to high production of energy by the respective cells. The contents of water soluble carbohydrates and proteins increased with increasing As concentrations while their hydrolyzing enzymes i.e. ? amylase and protease were decreasing with increase in As concentration. The activity of antioxidant enzymes, superoxide dismutase and peroxidase followed the increasing trend indicating the induction of oxidative stress under high concentration of As. Further, among the various varieties HD 2967 was the most tolerant variety and PBW 550 was most affected variety
  • Thumbnail Image
    Item
    Mutagenic Effect in Vegetables by Pesticides
    (Krishi Sanskriti Publications, 2013) Nag, Shilpa; Jain, A.K.; M.S., Dhanya
    The advent of pesticides in vegetable crops is to control insects, pathogens and weeds aimed at increasing the crop yield, but the applied pesticides are not fully reaching the target pests. It escapes to environment or accumulates in crops resulting in some deleterious changes. The disturbances were observed in physiological and cytological levels of the affected plants by blocking mitosis and producing mitotic and meiotic chromosome abnormalities. Some pesticides like acetamiprid, carbendazim, chlorpyriphos, cypermethrin, dichlorvos, dicofol, dimethoate, fenvalarate, indoxcarb, mancozeb, monocrotophos, profenophos, quinalphos, zineb etc. proved to be mutagens. Researchers reported abnormalities like chromosomes with inactivated centromeres, isochromosome, picnosis, vagrant, stickiness, bridges, precocious separation and lagging chromosomes, reduction in mitotic index, micronuclei, multipolar cells, sister chromatid exchanges, c- mitosis are common in vegetables. Such abnormalities were observed in kharif vegetables like Lycopersicon esculentum, Capsicum annum, Solanum melongena, Abelmoschus esculentus, Cucumis sativus, Vicia faba, Phaseolus vulgaris and rabi vegetables like Allium cepa, Coriandrum sativum, Raphanus sativus, Solanum tuberosum, Pisum sativum etc. The pesticides act as potent environmental mutagens that possess a threat to cause alterations in genetic makeup in vegetables.