Evaluation of bio-agents, synthetic insecticides and organic amendment against the root-knot nematode, <i>Meloidogyne</i> spp. in cardamom [<i>Elettaria cardamomum</i> (L.) Maton]

Abstract

&lt;p&gt; Investigations were made to study the effects of three nemato-pathogenic fungi&lt;em&gt; viz.&lt;/em&gt; &lt;em&gt;Purpureocillium lilacinum&lt;/em&gt;, &lt;em&gt;P. lilacinum&lt;/em&gt; + neem cake, &lt;em&gt;Pochonia chlamydosporia&lt;/em&gt; and&lt;em&gt; Trichoderma&lt;/em&gt; sp. as well as two synthetic insecticides (cartap hydrochloride and carbosulfan) against the Root-knot Nematodes (RKN) of cardamom at the farmers’ fields in three locations of Idukki district, Kerala, India during 2016- 2019. Results revealed that the combined application of &lt;em&gt;P. lilacinum&lt;/em&gt; with neem cake gave maximum reduction of typical symptoms of infestation like the leaf narrowing (6.42%) and root knot formation (1.32 nos.) followed by &lt;em&gt;P. chlamydosporia&lt;/em&gt; with 8.04% narrowed leaves and 1.83 root knots. The application of &lt;em&gt;P. lilacinum&lt;/em&gt; and neem cake in combination (0.82 kg/plant and 2.99) followed by&lt;em&gt; P. chlamydosporia&lt;/em&gt; (0.71 kg/plant and 2.71 recorded highest yield and Benefit Cost Ratio, respectively). Bio-control agents are therefore efficient and environmentally safer for managing the RKN in cardamom. Future studies can be directed to focus on the compatibility and efficiency enhancement of these bio-agents with organic amendments.&lt;/p&gt;