Screening of Cowpeas for Resistance to the Flower Bud Thrips, Megalurothrips sjostedti Trybom (Thysanoptera: Thripidae)

The extracts of pods of West African black pepper, Piper guineense, at 5, 10 and 20% (w/v), were applied at two, four and six weekly schedules to control the legume flower bud thrips, Megalurothrips sjostedti on flowers of cowpea, Vigna unguiculata. The trials were conducted for 2 years under rain fed conditions in the northern Guinea savanna region of Nigeria. The results showed that the M. sjostedti population was significantly controlled on treated plots compared with the untreated check in both years. The extracts at the 20 and 10% rates and with six or four weekly applications significantly (P < 0.05) reduced thrips pressure on cowpea flowers, were better than the 5% extract at all spraying schedules, and had the same efficacy as the synthetic insecticide treatment. Pod density per plant was significantly higher (P < 0.05) on plots treated with the 20% extract at six or four weekly applications compared to other extract rates and was similar to that of the synthetic insecticide treatment. Thus, the extracts could be a good alternative to the synthetic insecticides on organically managed farms as well as on farms of limited resource farmers in the tropics and subtropics.

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Genetic analysis of resistance to flower bud thrips (Megalurothrips sjostedti) in cowpea (Vigna unguiculata [L.] Walp.)

Euphytica ◽

10.1007/s10681-008-9776-4 ◽

2008 ◽

Vol 165 (1) ◽

pp. 145-154 ◽

Cited By ~ 6

Author(s):

E. E. Omo-Ikerodah ◽

C. A. Fatokun ◽

I. Fawole

Keyword(s):

Genetic Analysis ◽

Vigna Unguiculata ◽

Flower Bud ◽

Megalurothrips Sjostedti

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Screening of 25 cowpea genotypes for resistance to Megalurothrips sjostedti Trybom in southern Ghana

Legume Research - An International Journal ◽

10.18805/lr-477 ◽

2019 ◽

Author(s):

Patrick Bonney ◽

John Saviour Yaw Eleblu ◽

Vincent Eziah

Keyword(s):

Insect Pest ◽

Sub Saharan Africa ◽

Flower Bud ◽

Megalurothrips Sjostedti ◽

Lattice Design ◽

Cowpea Varieties ◽

Sub Saharan ◽

University Of Ghana ◽

Moderately Resistant

In sub-Saharan Africa, Megalurothrips sjostedti Trybom are the most destructive insect pest of cowpea. It causes approximately 100% reduction in cowpea yield. Synthetic insecticides are widely used in controlling this pest, however, health and environmental hazards are another challenge. This study sought to evaluate 25 cowpea genotypes from Ghana, Mali, Nigeria, Niger, Burkina Faso, Togo and South-Sudan for resistance to this pest under field screening using a 5 by 5 alpha lattice design with 2 checks at University of Ghana farms. The results revealed Laduni 1B as resistant, 20 moderately resistant and 4 susceptible genotypes were also identified in this study. In the determination of correlated and non-correlated variables, ten traits were reported important to the resistance of cowpea genotypes to flower bud thrips. The genotypes with resistance could be used to introgress the resistant trait into other preferred but susceptible cowpea varieties.

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Effect of Native Soap on Insect Pests and Grain Yield of Cowpea (Vigna unguiculata (L) Walp) in Asaba and Abraka during the Late Cropping Season in Delta State, Nigeria

Sustainable Agriculture Research ◽

10.5539/sar.v1n2p275 ◽

2012 ◽

Vol 1 (2) ◽

pp. 275 ◽

Cited By ~ 1

Author(s):

E. O. Egho ◽

E. C. Enujeke

Keyword(s):

Grain Yield ◽

Insect Pests ◽

Block Design ◽

Maruca Vitrata ◽

Flower Bud ◽

Megalurothrips Sjostedti ◽

Ecological Zones ◽

Cropping Season ◽

Pod Borer ◽

Legume Pod Borer

Studies were conducted to test the effectiveness of native soap against cowpea insect pests during the late cowpea cropping season in two agro-ecological zones-Asaba and Abraka, Delta State. Four major insect pests, namely the cowpea aphid, Aphis craccivora Koch, the legume flower bud thrips, Megalurothrips sjostedti Tryb, the legume pod borer, Maruca vitrata Fab and pod sucking bugs were studied. The experiment was made up of five treatments-1, 2 and 3 percent concentrations of native soap, cypermethrin (as conventional chemical and check) and a control. Each treatment was replicated three times. The experiment was arranged into a randomised complete block design (RCBD). The results showed that all the major insect pests occurred in the study areas but were more at Asaba compared to Abraka. Native soap was effective against A. craccivora and flower bud thrips population at Asaba. Maruca vitrata was not affected by soap application. Grain yield was high at Abraka and significantly (P<0.05) higher than Asaba. The use of native soap as non-conventional insecticide in cowpea insect pests management appears promising, more so as it is not expensive and safe to handle. Farmers may prefer it to synthetic chemical pesticides with their associated dangers.

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Genetic variability and trait association under thrips (Megalurothrips sjostedti Trybom) infestation in cowpea (Vigna unguiculata [L.] Walp.)

Euphytica ◽

10.1007/s10681-021-02849-1 ◽

2021 ◽

Vol 217 (6) ◽

Author(s):

Johnson Oluwaseyi Toyinbo ◽

Christian Fatokun ◽

Ousmane Boukar ◽

Morakinyo Abiodun Bamidele Fakorede

Keyword(s):

Genetic Variability ◽

Agronomic Traits ◽

Insect Pests ◽

Sub Saharan Africa ◽

Phenotypic Variance ◽

Flower Bud ◽

Megalurothrips Sjostedti ◽

Genetic Components ◽

Resistant Varieties ◽

Sub Saharan

AbstractFlower bud thrips is one of the most destructive insect pests of cowpea in sub-Saharan Africa. Information on genetic variability among cowpea germplasm and interrelationships among traits under thrips infestation would facilitate the development of resistant varieties. The objectives of the study were to assess genetic variability for thrips resistance, estimate heritability of yield and other traits and investigate inter-trait relationships under thrips infestation. One hundred and fifty-six cowpea lines, including one resistant and one susceptible check, were screened for resistance under natural infestation at two locations in Nigeria, in 2016. Test lines were scored for thrips damage weekly for three consecutive weeks, after removal of spreader plants, to obtain damage scores (DS) 1, 2 and 3 while data were collected on agronomic traits. The data were subjected to analysis of variance from which genetic components of the phenotypic variance were computed. Interrelationships among traits were determined using phenotypic and genotypic correlation, and sequential path analyses. Significant variability was observed among test lines. Lines TVu 6824 and TVNu 1307 were identified as possessing thrips resistance. DS3 had significant genetic and phenotypic correlations with DS1, DS2 and yield-related traits. Number of pods per peduncle, number of peduncles per plant and DS3 were identified as first-order traits. Heritability estimates ranged from 0.55 to 0.73. Genetic variability among the lines suggests the possibility of genetic control of thrips while number of pods per peduncle, number of peduncles per plant and DS3 would serve as useful selection criteria for thrips resistance.

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