Bio-efficacy of potassium phosphonate against nut rot disease of areca nut (&lt;em&gt;Areca catechu&lt;/em&gt; L.) in the northern Karnataka of India

G M Hegde

doi:10.4038/sljfa.v1i2.14

Abstract

Phytophthora arecaea, a causal agent of nut rot disease (koleroga) of areca nut (Areca catechu L.) is one of the major fungal pathogens affecting the crop in the northern Karnataka of India. The estimated loss associated with this disease extends up to 60%. In the endemic regions of India, the disease occurs immediately after the onset of the monsoon rains (June) and prevails till mid-August due to congenial weather conditions. For the effective management of this devastating disease, potassium phosphonate was tried during June and July 2013-2014 at the farmer’s fields. The results revealed that potassium phosphonate applied at the rate of 6.0 ml/L has reduced the per cent disease incidence (PDI) in areca nut (PDI=19.5%), where the results were on par (p>0.05) with metalaxy MZ applied at 2.0 g/L (PDI=16.81%) and Bordeaux mixture applied at 1% (w/v; PDI=18.84%). However, potassium phosphonate at 3.0 ml/L (PDI=43.10%) and 4.5 ml/L (PDI=39.45%) was not effective in reducing the PDI. The maximum PDI of 52.87% was recorded in unsprayed control plots. The highest yields of 26.42 q/h was recorded from the plots sprayed with metalaxy MZ at 2.0 g/L, which is in par (p>0.05) with potassium phosphonate applied at 6.0 ml/L (24.76 q/ha) and Bordeaux mixture at 1% (25.12q/ha). The lowest yield (12.48 q/ha) was recorded from the control (unsprayed) plots.

Highlights

Areca nut (Areca catechu L.), popularly known as betel nut, is an important plantation crops in India
The results revealed that potassium phosphonate applied at the rate of 6.0 ml/L (T3) significantly reduced the koleroga incidence in areca nut (19.48% p
The market sample of potassium phosphonate (Akomine®) applied at 3.0 ml/L showed a per cent disease incidence (PDI) of 36.18%

Summary

Introduction

Areca nut (Areca catechu L.), popularly known as betel nut, is an important plantation crops in India. This crop is being grown in an area of 0.38 m ha with an annual production of 0.48 mt in major cities such as Karnataka, Kerala, Assam, Maharashtra, West Bengal and Tamilnadu of India (Jose et al, 2008). The control measures suggested by the previous workers to control the disease comprised of either providing covers made out of areca nut leaf sheaths (kotte) or dried grass (karada) to areca nut bunches or spraying Bordeaux mixture (1% w/v) to the bunches 2-3 times (Narasimhan, 1922). The present study was undertaken to evaluate the bio-efficacy of a new molecule potassium phosphonate (Phosfik 8®) in managing koleroga of areca nut in the endemic region of Uttara Kannada district in India

Materials and Methods

Results and Discussion

Control