The Open Conference Proceedings Journal

2016, 7 : 144-148
Published online 2016 December 13. DOI: 10.2174/2210289201607010144
Publisher ID: TOPROCJ-7-1-144

RESEARCH ARTICLE
 Evaluation of High Beta Carotene Cassava Genotypes at Advanced Trial in Nigeria

N.L. Edoh, * , J. Adiele , I. Ndukwe , H. Ogbokiri , D.N. Njoku and C.N. Egesi

* Address correspondence to this author at the Biotechnology Programme, National Root Crops Research Institute, P.M.B. 7006 Umudike, Umuahia Abia State, ; Tel: +2348035662511; E-mail: , edohlink@yahoo.com

ABSTRACT

Thirteen cassava genotypes were evaluated from advanced field trial for total carotene content (TCC), % dry matter content (DMC), fresh root yield (FRY) and biotic stresses alongside two widely cultivated cassava varieties (UMUCASS 36 and TMS 30572) as checks in 2013/2014 cropping season at research station of National Root Crops Research Institute (NRCRI) Umudike in Nigeria. The objective of the experiment was to select promising clones for possible release to Nigeria farmers. The results of the TCC analysis ranged from 1.68-10.16 µg/g. Genotypes NR11/0063, NR11/0123 and NR11/0140 had TCC ranged from 10.47-8.72 (µg/g) which are above the national checks (UMUCASS 36 and TMS 30572) of 8.34 and 1.68(µg/g) respectively. The DMC of the genotypes ranged from 33.0-15.0 %. TMS 30572 gave the highest DMC (33.0%) while genotype NR11/0064 had the least (15.0%) DMC. Severity of cassava mosaic disease (CMD), cassava bacterial blight (CBB), cassava green mite (CGM) and cassava anthracnose disease (CAD) evaluated for 12 months varied among the genotypes. Symptom expressions of CMD, CBB and CAD were relatively higher (3.0) for genotype NR11/0123 and this resulted to low fresh root yield (FRY) of 18 t/ha whereas TMS 30572 with moderate severity (1.8) had a higher FRY of 32.6 t/ha. The severity of CGM was moderate across the genotypes with no significant difference (P<0.05) observed. Further analysis showed that CMD, CBB and CAD were significantly correlated (r=0.618, 0.699 and 0.621, p<0.05) with harvest index (HI) among the genotypes evaluated. Three genotypes were selected for further evaluation and possible release to Nigeria farmers.

Keywords:

Biotic stress, Cassava, High Beta-carotene, Harvest index.