Bio-potential of Aqueous Extract of Verbesina encelioides, Moringa oleifera, Cassia fistula against Meloidogyne incognita

Background: The Meloidogyne incognita is the most destructive pathogen and causes loss of yield of various economically important plants of various families. It is polyphagous in behaviour and has a high reproductive rate, these parameters are a hurdle in management of it. Various chemicals are used to control nematode worldwide that are very expensive and highly toxic to the environment and human beings. For ecologically safe method, three plants i.e. Verbesina encelioides, Moringa oleifera, Cassia fistula and their various parts such as leaf, stem and flower’s cold aqueous extracts were tried in vitro to test their nematicidal activity. Methods: Cold aqueous extracts (10% w/v) of each plant material were prepared by mixing 10g of each plant material in 100 ml of distilled water and kept aside for 48 hours. To estimate inhibition of egg hatching and mortality rate of second stage juveniles of Meloidogyne incognita, eggs and juveniles were exposed for 24, 48 and 72 hours in different concentrations (20 ppm to 200 ppm) of plant extracts. Result: All three tested plant extracts showed promising nematicidal activity against Meloidogyne incognita and the leaf extract of Moringa oleifera prevents the hatching of eggs. Inhibition of larval hatching from egg and nematode mortality rate were strongly influenced by concentration of extract, plant species and duration of exposure.

Verbesina encelioides: A Fast Spreading Weed in Semi-arid Regions of North-Western India. Is Climate Change Responsible?

Alterations in rainfall pattern and rise in temperature along with various anthropogenic disturbances are contributing greatly to biological invasion. In response to ongoing climate change, the sub-tropical and semi-arid regions are shifting towards dry deserts and arid regions, which create a propitious chance for the establishment of highly efficient and opportunistic invasive plant species at the cost of native vegetation. Verbesina encelioides is one of such exploitative plants spreading fast in many semi-arid as well as arid regions of the world. Although the presence of V. encelioides dates back to 1960s, but its emergence as a dominant invasive weed of dry areas is recent in India. The present study focused on the rapid spread of V. encelioides in the north-western states of India owing to its ecological traits as well as changing climate patterns of the country.

Remarks and clarifications on the type material of Ximenesia encelioides (Verbesina encelioides; Asteraceae, Heliantheae), with a new lectotype designation

In a recent paper, the name Ximenesia encelioides was lectotypified on material conserved at MA. However, the selected “lectotype” includes several fragments collected at three different times, and that herbarium sheet is therefore to be considered to contain three different specimens as defined in Art. 8.2 of the International Code of Nomenclature of algae, fungi and plants. This fact makes that “lectotype” invalid since contrary to Art. 8.1, and hence the previous lectotypification is to be disregarded. Accordingly, a new lectotype is designated for that name, currently accepted as Verbesina encelioides.