Bio

John H. Nderitu

Prof John H. Nderitu was born in 1952.

Publications


2018

2017

Wafula1, GO, Muthomi JW, Nderitu JH, Chemining’wa GN.  2017.  Efficacy of Potassium Salts of Fatty Acids in the Management of Thrips and Whitefly on Snap Beans. Sustainable Agriculture Research. 6(4):45-54.
Nderitu, JH.  2017.  A life of struggles. , Nairobinderitu_autobiography.pdf

2016

Hutchinson, DM, Andika DD, Kioko DE, Mulwa DR, Isutsa PD, Musieba MF.  2016.  Role of AIVs in Climate Smart Agriculture. , 2016role_of_aivs_in_climate_smart_agriculture.pdf
M. Otim, Kasina M, Nderitu J, Katafiire M, Mcharo M, Kaburu M, Bwire G, Bwire J, Ol F.  2016.  Effectiveness and profitability of insecticide formulations used for managing snap bean pests. Uganda Journal of Agricultural Sciences. 17 (1):111-124.Effectiveness and profitability of insecticide formulations used for managing snap bean pests1.pdf

2015

Evans, W, Nderitu, J., Cheminingwa.  2015.  management bean pests. , Nairobimgt_of_snap_beans_pests.pdf
(IIRR), TO,(KAPP) FO,(KAPP) EIC,(MKU) NJH,(IIRR) EM,(IIRR) CM,(IIRR) NB.  2015.  Fruits of our toil. , Nairobi: Ministry of Agriculture, Livestock and Fisheries Cathedral road, NairobiFruits of our toil kapap_book_d10-1.pdf
J., M, J.N. K, D. K, G.O. A, J.H N.  2015.  Prolonging the shelf-life of seed potato tubers at farm level: Cold storage or Diffused light store. International Journal of Horticulture. 5(12):1-4.prolonging_the_shelf.pdf

2014

  2014.  G. O. Wafula, J. W. Muthomi, J. H. Nderitu and G. N. Chemining'wa (2014). Management of snapbean pests by integrated seed dressing, foliar sprays and intercropping with maize. Conference on HAK, Nairobi, 1-5th December 2014. Abstract

MANAGEMENT OF SNAP BEAN PESTS BY INTEGRATING SEED DRESSING, FOLIAR SPRAYS AND INTERCROPPING WITH MAIZE
G. O. Wafula*, J. W. Muthomi, J. H. Nderitu2 and G. N. Chemining’wa
Department of Plant Science and Crop Protection,University of Nairobi. P. O Box 29053-00625 Kangemi, Nairobi, Kenya
2. Mount Kenya University, P. O. Box 342-01000, Thika, Kenya
Email: ongoya@gmail.com, Tel. 0723144690
Abstract
Insect pests remain a major constratint in the production of snap beans and farmers mainly rely on chemical pesticides to manage the insect pests and diseases. However, the introduction of maximum residue levels (MRLs) for export vegetables by European markets pose a challenge to the use of pesticides. This study was carried out to develop sustainable options of managing snap bean pests and reducing chemical residues on snap bean produce.
Field experiments were carried out in farmers’ fields in Mwea and Embu from July 2013 to January 2014 for two planting cycles under irrigation. The integrated pest management strategies evaluated included: i) seed dressing only, ii) seed dressing followed by three neem sprays, iii) seed dressing followed by two pyrethrid sprays and one neem spray, iv) seed dressing followed by three pyrethrin sprays and intercropping snap bean with maize, v) seed dressing followed by two pyrethrin sprays plus one spray with a biological product, vi) seed dressing followed by two neem sprays plus one spray with a biological product, and vii) two pyrethrin sprays and one neem spray only. The data collected included: emergence, plant stand, nodulation, thrips population, bean stem maggot population, whitefly population, yield and pest damage. The combination of seed dressing, two pyrethrin sprays and neem applied at the vegetative stage, early flowering and early podding reduced white fly and thrips population by up to 54% and 60% respectively. Similar results were also observed on plots where seeds dressing was done before planting combined with intercropping with maize plus three pyrethrin sprays at the vegetative stage, early flowering and early podding. Seed dressing had a direct effect on the bean stem maggots that attack the seedling at a very young stage. Spraying with pyrethrin sprays had a quick knockdown effect on the population of whitefly and thrips while the maize intercrop also reduced the pest population. These options also reduced pod damage due to thrips by up to 75 and 93% and increased yield of extra-fine by up to 157 and 162% and fine pods by up to 148 and 133%. The results showed that seed dressing followed by two pesthrin sprays at the vegetative stage and early flowering stage plus a single spray with Nimbecidine at early podding, sprays and intercropping with maize were effective in managing snap bean pests. This demonstrates that integrated pest management options would be viable alternatives to chemical pesticides thereby enabling farmers meet the strict maximum chemical residue level requirements set by European consumers.

Key words: Phaseolus vulgaris L, seed dressing, bio-pesticides, intercropping, integrated pest management

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