Relative Levels of Tolerance to Pea Aphid (Acyrthosiphon pisum Harris) in Selected Lentil Genotypes in Ethiopia

doi:10.7176/jbah/11-22-02

Abstract

The experiment was conducted with five lentil genotypes of known reaction to pea aphid for resistance. The trail was carried out with two identical but separate experiments as infested and un-infested trial under DZARC lath house. Infested seedlings were compared with uninfested ones in terms of plant height, biomass, root weight, and leaf area to quantify tolerance. The field performance of those lentil genotypes used in the experiments was assessed at Chefe Donsa substation, which is found in the East Shewa administrative zone, Ethiopia. Alemaya(lentil varity) reduces pea aphid damage cumulatively by the reduced percent dry and fresh biomass, percent plant height reduction and increased dry biomass, plant re-growth after 12 days of infestation compared with other tested genotypes, thus Alemaya had high tolerance to A. pisum. Similarly, comparable tolerance was found on ILL-7664 which exhibited longer plant re-growth, increased dry biomass after 12 days of infestation compared with other tested genotypes, except Alemaya. Chalow also showed reduced percent plant height and dry biomass reduction and increased leaf number after 12 days of infestation. Using genotypes that had tolerance for pea aphid management is wise decision as it reduces selection pressure on A. pisum. Alemaya (genotype which had tolerant resistance) is more important for integrated pest management program (IPM) than all the remaining tested genotypes. Keyword s : tolerance, field resistance, pea aphid, lentil DOI: 10.7176/JBAH/11-22-02 Publication date: November 30 th 2021

Highlights

Wide use of synthetic insecticides for the control of major pests has resulted in more pest problem due to upset of balance between insect and natural enemies, insecticide resistance development, and effect on non target beneficial organisms (Thomas and Waage, 1996)
Smallest plant height reduction caused by 10 pea aphids feeding for 12 days was on Alemaya, followed by ILL7664 and Chalew; whereas the highest plant height reduction was recorded on ACC-21688 (Table 1)
Lath house and field studies were conducted for better understanding of category of resistance in lentil genotypes to A. pisum

Summary

Introduction

Wide use of synthetic insecticides for the control of major pests has resulted in more pest problem due to upset of balance between insect and natural enemies, insecticide resistance development, and effect on non target beneficial organisms (Thomas and Waage, 1996). Such adverse effects of dependence on chemical insecticides prompted for an increased interest in the development of integrated pest management (IPM) program, which is sustainable and environmentally friendly pest management method. IPM uses different pest management tactics such as cultural practices, host plant resistance, semi chemicals, biological control, etc. From 16 promising genotypes that gave better yield under the prevailing aphid infestation pressure Alemaya, ILL-7664, ILL-4422, ILL-2595 and R-186 were included in current study

Methods

Findings

Discussion

Conclusion