EJAS-12364.pdf

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European Journal of Applied Sciences – Vol. 10, No. 3

Publication Date: June 25, 2022

DOI:10.14738/aivp.103.12364.

Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity

of Hybrid Varieties of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European

Journal of Applied Sciences, 10(3). 300-317.

Services for Science and Education – United Kingdom

Evaluation of the Productivity of Hybrid Maize (Zea Mays L.)

Varieties under Tropical Climatic Conditions in the Sudanian

Zone of Burkina Faso

Abdoulazize BANHORO

Joseph KI-ZERBO University

Doctoral School of Sciences and Technology

Biosciences Laboratory, 03 BP 7021, Ouagadougou 03, Burkina Faso

Rasmata NANA

Joseph KI-ZERBO University

Doctoral School of Sciences and Technology

Biosciences Laboratory, 03 BP 7021, Ouagadougou 03, Burkina Faso

Hawa Temene KONE

SEMAFORT Seed Company (Strong African Seeds)

01 BP 168 Bobo-Dioulasso RS 01, Burkina Faso

Aboubakar SORY

Joseph KI-ZERBO University

Doctoral School of Sciences and Technology

Biosciences Laboratory, 03 BP 7021, Ouagadougou 03, Burkina Faso

Mahamadi Hamed OUEDRAOGO

Joseph KI-ZERBO University

Doctoral School of Sciences and Technology

Biosciences Laboratory, 03 BP 7021, Ouagadougou 03, Burkina Faso

Mahamadou SAWADOGO

Joseph KI-ZERBO University

Doctoral School of Sciences and Technology

Biosciences Laboratory, 03 BP 7021, Ouagadougou 03, Burkina Faso

Bruno TINLAND

SEMAFORT Seed Company (Strong African Seeds)

01 BP 168 Bobo-Dioulasso RS 01, Burkina Faso

ABSTRACT

In Burkina Faso, maize yields are very low in the farming environment because its

production is severely limited by biotic and abiotic constraints. To meet the

productivity challenge, hybrid maize varieties would be a major asset. However,

hybrids are difficult to access, as their breeding schemes are complex and costly.

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301

Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity of Hybrid Varieties

of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European Journal of Applied Sciences, 10(3). 300-

317.

URL: http://dx.doi.org/10.14738/aivp.103.12364

The objective of this study is to identify hybrids with high yield potential that are

adapted to the climatic conditions of Burkina Faso. To this end, 124 hybrid maize

varieties and four control varieties were evaluated in the rainy season in the

southern Sudanian zone of Burkina Faso. The experimental design used is an alpha

lattice with three replications. Observations on the agro-morphological parameters

made it possible to classify the material evaluated into three groups according to

the productivity of the varieties. All the varieties evaluated had an intermediate

cycle of 100 to 110 days at maturity. The best performing hybrids showed a grain

yield advantage of between 2 and 110% compared to the control varieties. Among

these hybrids, 25 of them showed a grain yield advantage of between 1.5 and 5.5

t/ha over the controls. These varieties are to be subjected to multi-location and

multi-annual tests in order to evaluate the stability of their yields and to allow their

inclusion in the national catalogue. At the end of these tests, the best varieties could

be proposed for extension programs in the farming community.

Keywords: Zea mays, hybrids, yield, Burkina Faso

INTRODUCTION

Maize (Zea mays) is a cereal grown in various agro-ecological zones around the world and is

the staple food of many populations [12]. It is the most produced cereal in the world ahead of

wheat with a global production of about 1.134 billion tons in 2017 [11]. In Africa, maize is an

important subsistence crop for millions of smallholders who produce it for food and feed but

also as a source of income [26].

In Burkina, maize is the leading cereal produced with a total production in 2018 of about 1.78

million tons [14]. In addition to its direct contribution to feeding the population, maize offers

numerous outlets for livestock development, exports to other countries and various industrial

uses [3] ; [15]. However, maize yield is considerably low in the farming environment due to

biotic and abiotic constraints as well as socio-economic factors [8]. Indeed, the mean of maize

yield in Burkina Faso is less than 2 t/ha. However, the productivity has increased from 0.6 t in

1968 to 1.6 t /ha in 2017 [11]. This low productivity is mainly due to the extensive nature of

maize production in the country, which is many based on open pollination varieties that have

essentially of low yield potential [9]. To meet the challenge of maize productivity, hybrid

varieties would be a major asset as they have good agronomic performances favoring high

yields and good resistance to pests [4]. However, hybrids are difficult to access because their

breeding schemes are complex and costly [3].

The present study was initiated to make available hybrid varieties adapted to local ecological

conditions and contribute in the improvement of maize productivity in Burkina Faso. The

general objective of the study is to evaluate the agronomic performance of 124 sub-tropical

maize hybrid varieties. Specifically, the study aims to (i) characterize the cycle of hybrid

varieties, (ii) evaluate their agro-morphological characteristics and (iii) identify hybrids of

agricultural interest to farmers in Burkina Faso.

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European Journal of Applied Sciences (EJAS) Vol. 10, Issue 3, June-2022

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MATERIALS AND METHODS

Experimental site

The experiment was conducted in “Toumousseni”, a village in the southwest of Burkina Faso in

the province “Comoe”. The site is located 25 km from Banfora (Figure 1) on the Banfora-Sindou

road, on the operating site of the company "DRANA FARMING". The geographical coordinates

of the experimental site are 10°40' N and 04°56' W. The climate in this area is Soudanian and is

characterized by two seasons [16]; a rainy season from April to October and a dry season from

November to March [17]. The rainfall recorded during the experiment was 1382.6 mm spread

between March and August for 62 rainy days (Figure 1). This amount of rainfall recorded would

be very favorable to maize production, which is a water-demanding species [12]. July was the

wettest month with a rainfall of over 293 mm. The temperature averaged 27.89°C during the

trial period.

Figure 1: Rainfall diagram of the Banfora area during the experiment

Source of figures: West Regional Directorate of Environmental and Agricultural Research

Plant material

The plant material is composed of 124 hybrid maize varieties from the company Strong African

Seed (SEMAFORT) and 4 controls which are local varieties. Among these 124 hybrid varieties,

120 originated from Mexico and were coded SX8-121 to SX8-240. The four other hybrids

evaluated, coded MAZ-20, MAZ-21, MAZ-23 and MAZ-24, come from Syngenta Mali. The control

varieties are SR21, Bondofa, Komsaya and WE3205. The control varieties were used as a

reference for maturity cycle, yield and diseases. Thus, the variety Komsaya was used as an early

maturity reference. The varieties SR21 and Bondofa were used as intermediate maturity

references. On the other hand, the varieties WE3205, Komsaya and Bondofa were used as

reference for yield.

METHODS

Experimental design

The experimental design used was an alpha-lattice with 3 replications. Each replication was

composed of four 4 sub-blocks with 32 varieties and each variety was sown on an elementary

plot represented by a line of 5.2 m.

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Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity of Hybrid Varieties

of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European Journal of Applied Sciences, 10(3). 300-

317.

URL: http://dx.doi.org/10.14738/aivp.103.12364

The sowing was carried out with 3 seeds per pocket at a spacing of 0.80 m x 0.40 m. The sowing

density, after a removal and keeping two-plant per-pot, was 26 plants per elementary plot,

corresponding at 62,500 plants/ha. Two border lines were made at the ends of the replications.

Field management

The trial was established on 05/07/2018. Field management consisted in weed control, organic

and mineral fertilization and phytosanitary treatments against armyworm (Spodoptera

frugiperda) and others pest attacks. Fertilizer quantities were applied under intensive

production conditions on all the elementary plots: (i) 5 t/ha of compost was spread 14 days

before sowing corresponding to 2.08 kg for each elementary plot; (ii) 200 kg/ha of NPK (14-

23-14) applied on 15 days after sowing (DAS) corresponding to 83.2 g per elementary plot; (iii)

150 kg/ha of urea (46-00-00): 100 kg/ha of urea applied on 30 days after sowing and 50 kg/ha

of urea applied on 45 days after sowing corresponding to 62.4 g per unit plot. Armyworm

attacks were detected 14 days after sowing and were frequent until plant maturity. The

insecticides Emacot (Emamectin benzoate) and Indoxa (Indoxacarb) were used in an

intercalated manner for armyworm control.

Data collection

Data collection focused on crop cycle parameters, agro-morphological traits and grain yield of

varieties. Thus, these quantitative and qualitative parameters were selected from the studies of

Elola (2012) and in the CIMMYT/IBPGR (1991) maize descriptor [5] [10]. These parameters

are as follows:

• Percentage of emergence (POE): This was assessed on the basis of the proportion of

emerged plants in relation to the quantity of grain sown in the elementary plot. Thus, the

number of emerged plants was counted at 10 days after sowing (DAS) in each elementary plot.

The percentage lift was calculated using the following formula:

!"! = $

!"#

!$$%& ())

With: PEP: Percentage of emergence plants; NEP: Number of emergence plants; NSS: Number

of seeds sown

• Plant height (PH): measured in centimeters after anthesis from the base to the last node

before the panicle, using a measuring rod on a randomly selected sample of 10 plants per

working plot;

• Height of ear insertion (HEI): This consist to the ear insertion height from the base of the

plant to the insertion node of the main ear. It was evaluated in centimeters on a sample of 10

plants per useful plot, using the height gauge, chosen randomly;

• Percentage of lodging (PL): this corresponds to the proportion of lodged plants in the

elementary plot. It was evaluated by considering, per useful plot, the number of plants lodged

at maturity. The counts carried out made it possible to determine the percentage of lodging

using the following formula:

!* = $

!%#

!##%& ())

With: PL: Percentage of Lodging; NLP: Number of lodged plants; TNP: Total number of plants

in the plot.

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European Journal of Applied Sciences (EJAS) Vol. 10, Issue 3, June-2022

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• Percentage of breakage (PB): This was assessed at maturity by counting the number of

plants that had a broken stem before the main ear in each plot. This operation was carried out

simultaneously with the pouring operation and the percentage of breakage was determined

using the following formula:

!+ = $

!&#

'!#%& ())

With: PB: Percentage of breakage; NBP: Number of broken plants; TNP: Total number of plants

in the plot.

• Number of days to 50% tasseling (NDT): this was assessed by counting the number of

days from sowing when the tasseling on half of the plants in the elementary plot;

• Number of days to 50% silking (NDS): this was assessed by counting the number of days

between sowing and silking on half of the plants in the elementary plot.

• Number of days to 50% maturity (NDM): this was determined by counting the number of

days between sowing and the day when 50% of the plants in the plot had dry spathes (absence

of green color on the spathes);

• Grain yield (GY): this is the evaluation of variety productivity based on the weight of the

harvested ear, the grains and the relative humidity of the grains after drying. This yield was

calculated from the following formula:

,- = ." &/

,.0

.0"1& /

()) − 3

45 1 &

()

With: WE: weight in kg of harvested ears per elementary plot; WSE weight in kg of the sampled

ears; GWS: grains weight in kg of the sampled ears; H: Relative humidity of grains after drying;

A: area of the plot in square meters.

• Recording of leaf disease (RLD): Diseases were observed at the flowering stage on the

leaves. The diseases recorded were Helminthosporiosis (HEL), Fusarium (FUS), Maize Streak

(MSV) and, Rust (R). These records were made by counting the number of infected plants and

the degree of infection in each useful plot. For each disease observed, the percentage of infected

plants per plot was calculated according to the following formula:

!7! = /

87!

98!1& ())

With: PIP: Percentage of infected plants; NPI: Number of infected plants; TNP: Total number of

plants in the plot.

Based on the percentages obtained, scores on a scale of 1 to 5 were assigned to the varieties

(Table II). Each score corresponds to the level of infection of the plants in the useful plots.

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Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity of Hybrid Varieties

of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European Journal of Applied Sciences, 10(3). 300-

317.

URL: http://dx.doi.org/10.14738/aivp.103.12364

Table I: Disease scores corresponding to percentages of infected plants

Disease

score Appearance of plants corresponding to infection levels

1 Very mild infection:

• Very few leaf lesions, which are usually found on the first few leaves (0 - 10%);

Mild infection :

• low to moderate number of lesions on leaves below the ear;

• no lesions on leaves above the ear (11-25%);

Moderate infection :

• moderate to high number of lesions on leaves below the ear;

• few lesions above the ear (26-50%);

severe infection:

• significant number of lesions on the leaves below the ear;

• moderate to high number of lesions on leaves above the ear (51-75%);

Very severe infection:

• all leaves show a significant number of lesions.

• the plant dies prematurely and the grains are partially filled (76-100%).

Source: CIMMYT (1985)

According to Sanon (2003) and Dabiré (2000) this rating from 1 to 5 allows to classify

genotypes into three groups based on their scores (Table II) [25]; [7].

Table II: Grouping of material according to disease score

Group Note

Resistant hybrid or line 1- 2,5

Tolerant hybrid or line 2,6-3,5

sensitive hybrid or line 3,6-5

Following data collection, the best hybrids were identified using a yield comparison test,

compared to controls. This test has been used by several authors to compare new varieties with

controls under study [21]; [10]; [24]. The following formula was used to calculate the

percentage of superiority of the varieties evaluated over the controls.

!-6 = /

,-9 − ,-:

,-: 1& ())

With: PYA: Percentage of yield advantage of the material evaluated; GYT: grain yield of the

material tested; GYC: grain yield of the control variety.

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European Journal of Applied Sciences (EJAS) Vol. 10, Issue 3, June-2022

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DATA ANALYSIS

Data analysis was performed with XLSTAT 2016 and Minitab 18.1. Descriptive statistics (mean,

coefficient of variation, minimum and maximum) of the parameters were performed using

Minitab 18.1. The mean of the disease scores was also calculated from this software. A

classification according to the leaves scores, using Excel 2016, made it possible to group the

hybrids according to their sensitivity, tolerance or resistance indices for each disease

considered.

Analyses of variance (ANOVA), bi-variate (Pearson correlation) and multi-variate (PCA, HAC,

and DFA) were performed with XLSTAT 2016 software. The analysis of variance (ANOVA) and

the Newman-Keuls test at the 5% threshold were performed to assess the level of variability of

the material. Principal Component Analysis (PCA) was performed to identify the most

representative quantitative parameters. The correlation matrix was performed to study the

association of these variables. These variables were used for the Hierarchical Ascending

Classification (HAC) according to Ward's aggregation method using the Euclidean distance. This

classification made it possible to study the organization of the variability of the material

evaluated. The groups resulting from this classification were characterized using discriminant

factor analysis (DFA).

RESULTS

Agro-morphological characterization of hybrids

Diversity of agro-morphological parameters

The varieties evaluated showed a great diversity regarding to plant height (PH), height of ear

insertion (HEI), rate of lodged plants (PL), rate of broken plants (PB), grain yield (GY) and

diseases such as helminthosporiosis (HEL), maize streak virus (MSV) and rust (R) (Table IV).

These parameters showed a high coefficient of variation ranging from 16% to 80.10 %. But,

parameters like percentage of emergence (POE), number of days to 50% tasseling (NDT),

number of days to 50% silking (NDS), number of days to plant maturity (NDM) and Fusarium

(FUS) leaf scores showed low coefficients of variation (Table IV). Disease scores have been used

to study the diversity among varieties and group them according to their sensitivity, tolerance

or resistance indices for each disease considered. Leaf scores for helminthosporiosis and maize

streak virus averaged 3.4. Varieties with resistance to these diseases ratings scored 1 and those

with susceptibility ratings scored 5. In addition, scores ranged from 1 to 4 for rust with an

average of 1.4 and from 3 to 5 for Fusarium with an average of 5. In addition, the analyses

percentage of leaf score showed that for helminthosporiosis (Picture 4a), 42% of the hybrid

varieties showed susceptibility to the disease, and 48% showed tolerance and 10% showed

resistance. Compared to the control varieties SR21 and WE3205, about 58% of the hybrids

showed good tolerance to helminthosporiosis. About 52% of the evaluated hybrids showed a

good score against maize streak infection (MSV) compared to the controls WE3205, SR21 and

Komsaya (Figure 4d) and 48% of the hybrids showed a susceptibility index to MSV. In addition,

all hybrids tested as well as the controls were susceptible to Fusarium with an average score

ranging from 4.3 to 5 (Figure 4c). However, no genotype showed susceptibility to rust (Figure

4b). Fusarium and rust infection of the plants varied little within the studied accession and were

therefore not considered to distinguish the hybrids.

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Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity of Hybrid Varieties

of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European Journal of Applied Sciences, 10(3). 300-

317.

URL: http://dx.doi.org/10.14738/aivp.103.12364

Picture 1: Diseases observed on the plants:

A- Helminthosporiosis; B- rust; C-fusarium; D-streak

On the other hand, the hybrids tested generally have a good percentage of emergence (POE),

up to 100% with an average of about 90%. However, some hybrids had a low emergence

percentage (33%). As for plant height (PH), there is a wide dispersion around the average. Low

plants were 0.80 m high and high plants were 3.0 m high. In addition, the percentage of lodging

was variable between the different hybrid groups. Thus, a high resistance to lodging (0%

lodging) for some hybrids and a high susceptibility (80% lodging) for other hybrids were

observed. The number of days to 50% tasseling was on average about 56 days with a variation

from 50 days to 66 days. All hybrids had an intermediate maturity cycle ranging from 101 days

to 110 days with an average of 105 days. The yield of the germplasm evaluated ranged from 0.5

t/ha to 10.4 t/ha with an average of 5.8 t/ha Analysis of variance showed that quantitative traits

such as percent emergence (POE), plant height (PH), ear insertion level (HEI), percent breakage

(PB), days to 50% tasseling (NDT), days to 50% silking (NDS) and days to plant maturity (NDM)

significantly discriminate between accessions (p < 0.05) (Table III).

Table III: Descriptive statistics and analysis of variance for the 14 variables studied.

ns: difference not significant at the 5% level; *: difference significant at the 5% level; **: difference highly

significant at the 5% level; ***: difference very highly significant at the 5% level. POE: percentage of emergence;

NDT: male semi-flowering date; NDS: female semi-flowering date; PH: plant height; HEI: ear insertion level; PL:

lodging percentage; PB: breakage percentage; NDM: number of days to maturity; GY: grain yield; HEL:

Variables Min. Max. Mean. CV (%) F

POE (%) 33 100 90 11,13 1,7***

HP (m) 0,8 3,0 1,5 16,14 3***

NIE (m) 0,3 1,9 0,8 26,05 2,6***

PL (%) 0 80 6 80,90 1,3ns

PB (%) 0 31 2 75,10 1,5**

NDT 50 66 56 5,47 1,7***

NDS 51 69 59 5,45 1,3*

NDM 101 110 105 2,22 2***

GY (t/ha) 0,5 10,4 5,8 32,02 2,7***

HEL (score) 1 5 3,4 33,5 1,2ns

FUS (score) 3 5 5 4,42 0,9ns

MSV (score) 1 5 3,4 25,9 1,1ns

R (score) 1 4 1,4 54,94 1,5**

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helminthosporiosis; FUS: fusarium; MSV: corn stripe; R: rust; F: Fischer probability at the 5% threshold; Max.

Maximum; Min.: minimum; Avg. Mean; CV: coefficient of variation, m: meter; t/ha: tons/hectare.

Correlations between parameters

The Pearson correlation matrix showed significant correlations between several pairs of

quantitative parameters (Table V). Indeed, yield is strongly positively correlated with plant

height (r = 0.582), but negatively correlated with female semi-flowering cycle (r = - 0.513). On

the other hand, there was a strong positive correlation between the number of days at 50%

tasseling and the number of days at 50% female flowering (r = 0.884)

Table IV: Correlation matrix between measured variables

Variables PL GY PL PB NDT NDS NDM PH

GY 0,236***

PL 0,071 0,076

PB -0,023 -0,02 0,249***

NDT -0,104* -0,41*** -0,056 -0,01

NDS -0,102* -0,51*** -0,04 -0,02 0,884***

NDM -0,095 -0,21*** -0,071 -0,03 0,276*** 0,294***

PH 0,085 0,582*** 0,185*** 0,032 -0,228*** -0,282*** -0,14**

HEI 0,085 0,381*** 0,218*** 0,182*** 0,024 -0,041 -0,1 0,49***

*: correlations significant at the 5% level, **: correlations highly significant at the 5% level; ***: correlations very

highly significant at the 5% level, POE: percentage of emergence; PH: plant height; HEI: ear insertion level; PL:

percentage of lodging; PB: percentage of breakage; GY: grain yield; NDT: number of days to 50% male flowering;

NDS: number of days to 50% female flowering; NDM: number of days to maturity

Description of the variability of the plant material

Principal component factor analysis grouped the quantitative parameters into 3 axes (F1, F2

and F3) which explained 61.45% of the variability among tested varieties (Table V). The

analysis of correlations between variables and factors showed that the percentage of

emergence, plant height, grain yield, number of days to 50% tasseling, number of days to 50%

silking and number of days to maturity of the plants contributed most to the construction of the

first axis, which explained 31.15% of the variance (Table V). This axis can therefore be

described as the axis that determines the yield potential, vegetative and reproductive

development of tested varieties. While the height of ear insertion contributes most to the

formation of the second axis which explains 17.56% of the observed variability. This axis

defines the sensitivity of the plants to lodging and breakage. Two parameters, namely the

percentage of lodged plants and the percentage of broken plants contribute to the formation of

the third axis. This axis, which accounts for 12.73% of the observed variability, provides

additional information to axis 2.

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Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity of Hybrid Varieties

of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European Journal of Applied Sciences, 10(3). 300-

317.

URL: http://dx.doi.org/10.14738/aivp.103.12364

Table V: Eigenvectors and squared cosines of the characters in relation to the PCA components

Variables F1 F2 F3

POE 0,276 0,045 0,231

PH 0,669 0,409 0,301

HEI 0,436 0,695 0,188

PL 0,238 0,486 -0,500

PB 0,099 0,409 -0,706

GY 0,800 0,102 0,307

NDT -0,743 0,519 0,239

NDS -0,800 0,471 0,181

NDM -0,438 0,147 0,187

Proper value 2,804 1,581 1,146

Variability (%) 31,154 17,564 12,732

% cumulative 31,154 48,718 61,450

POE: percentage of emergence; HP: plant height; NIE: ear insertion level; PV: percentage of lodging; PC:

percentage of breakage; GY: grain yield; NDT: male semi-flowering date; NDS: female 50% flowering

date; NDM: number of days to maturity

Structuring variability according to productivity and plant height

The dendrogram of hierarchical clustering (HC) revealed three distinct groups on the basis of

grain yield and plant height at maturity (Figure 2). Wilks' lamda and Box test (P < 0.0001)

confirm that the three groups are quite distinct entities from each other.

Figure 1 : Dendrogram of hierarchical clustering

Group 1 Group 3 Group 3

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Characteristics of the groups

Discriminant factor analysis (DFA) and analysis of variance (ANOVA) performed on the

different groups resulting from the hierarchical ascending classification, allowed to highlight

the main distinctive traits which are GY, PH, HEI, Hel, MSV, NDT and NDS (Table VII). The

analysis of variance also showed highly significant differences between the three groups for the

variables yield (p = 0.000), plant height (p = 0.000), ear insertion level (p = 0.000), days to 50%

female flowering (p = 0.001), helminthosporiosis (p = 0.005) and maize streak (p = 0.002)

(Table VII). These analyses confirm that the HC groups are well separated from each other.

Thus, group 1 is composed of low height hybrid varieties with low yield (2.5 t/ha). These

hybrids showed susceptibility to streak but are tolerant to lodging, breakage and

helminthosporiosis (Table VII). Group 2 is composed of hybrid varieties with intermediate

plant height and an average yield of 6.2 t/ha. These hybrids showed tolerance indices to

helminthosporiosis and maize streak virus, but were susceptible to lodging compared to Group

1 hybrids. Group 3 consists of hybrids that have taller plants with higher yields (7.5 t/ha). The

hybrids in this group were tolerant to lodging, stripe and helminthosporiosis.

Table VI: Characteristics of the groups resulting from the hierarchical clustering (HAC)

Variables Group 1 Group 2 Group 3 Pr > F

POE 87,3% a 90,2% b 92,1% b 0,023

HP 1,3 a 1,5 b 1,8 c 0,000

NIE 0,7 a 0,8 b 0,9 c 0,000

PV 4,7% a 6,2% a 6,3% a 0,498

PC 2,2% a 2% a 2,2% a 0,915

GY 4,2 a 6,2 b 7,5 c 0,000

NDT 56,3b 55,7 ab 54,7 a 0,028

NJ50%FF 59,9 b 58,8 a 57,8 a 0,001

NDM 105,7 b 105,2 ab 104,7 a 0,078

HEL 3,2 a 3,4 a 3,8 b 0,005

MSV 3,6 c 3,4 b 3,1 a 0,002

Numbers followed by the same letter are not significantly different. POE: percentage of emergence; NDT:

male semi-flowering date; NDT: female semi-flowering date; HP: plant height; NIE: ear insertion level; PV: lodging

percentage; PC: breakage percentage; NDM: number of days to maturity; GY: grain yield

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Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity of Hybrid Varieties

of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European Journal of Applied Sciences, 10(3). 300-

317.

URL: http://dx.doi.org/10.14738/aivp.103.12364

Agronomic performance of hybrids

As a result of the yield comparison test, hybrids from the same genotypic group with a yield

potential 25% higher than the control were identified as performing well. However, hydrids

that were less than 25% higher yielding than the control was considered to have similar yield

potential to the control. Thus, 4 hybrid varieties (SX8-186, SX8-213, SX8-149, SX8-143) from

group 1, with an average yield of 5.5 t/ha, which is 25% higher than the yield of the lowest

yielding control variety SR21 (Table VIII). The other hybrids in group 1 had yields ranging from

2 to 4.8 t/ha; the yields of these hybrids are lower or equal to those of the control varieties SR21

and Bondofa. On the other hand, most of the hybrids in group 2 had higher yields than SR21

and Bondofa. Also, within this group, 24 hybrids yielded 25% more than the control Komsaya

(5.3 t/ha). The best performing hybrids in group 2 that yielded more than the control WE3205

(7.2 t/ha) were SX8-198, SX8-233, SX8-128, SX8-195, SX8-210, SX8-238, SX8-171, SX8-163,

SX8-131, SX8-172, SX8-174 (Table VIII). The hybrids in group 3 each showed higher yields than

the control varieties SR21, Bondofa and Komsaya with yield superiority ranging from 20% to

110% (Table VIII). The yields of these hybrids ranged from 6.4 to 8.7 t/ha. However, the hybrids

SX8-121, SX8-226, SX8-173 and SX8-136 in group 3 had yields 21%, 21%, 19% and 17% higher

than the control variety WE3205, respectively. These varieties expressed the most significant

yields with an average of 8.5 t/ha. In addition to these varieties, seven other hybrid varieties in

group 3 showed slightly higher yields than the control WE3205, with a rate of increase ranging

from 2% to 7% (Table VIII). The other hybrids in group 3 had lower yields than WE3205 (Table

VIII).

Page 13 of 19

European Journal of Applied Sciences – Vol. 10, No. 3

Publication Date: June 25, 2022

DOI:10.14738/aivp.103.12364.

Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity

of Hybrid Varieties of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European

Journal of Applied Sciences, 10(3). 300-317.

Services for Science and Education – United Kingdom

Table VIII: Best hybrid varieties in grain yield of genotypic groups from CAH

N°

G1 GY SD1 SD7 SD8 SD9

N°

G2 G

SD1 SD7 SD8 SD9

N°

G3 G

SD1 SD7 SD8 SD9

1 SX8-

186

5,9 -

18%

11% 1 SX8-

198

11% 93

% 1 SX8-

121

21% 110

106

2 SX8-

213

5,5 -

23%

4% 2 SX8-

233

11% 92

2 SX8-

129

7% 86% 82% 45

3 SX8-

149

5,5 -

24%

3% 3 SX8-

128

8% 87

% 3 SX8-

136

17% 103

99% 58

4 SX8-

143

5,3 -

26%

0% 4 SX8-

195

7% 85

% 4 SX8-

139

-5% 65% 62% 28

5 SX8-

144

5,1 -

29%

-3% 5 SX8-

210

6% 84

% 5 SX8-

147

2% 78% 74% 38

6 SX8-

125

5,1 -

29%

-4% 6 SX8-

238

4% 81

% 6 SX8-

150

-8% 59% 56% 24

7 SX8-

135

5,0 -

30%

-5% 7 SX8-

171

3% 78

% 7 SX8-

155

3% 79% 76% 39

8 SX8-

168

5,0 -

30%

-5% 8 SX8-

163

2% 77

% 8 SX8-

160

-3% 68% 65% 31

9 SX8-

216

5,0 -

31%

-6% 9 SX8-

131

2% 76

9 SX8-

169

3% 78% 75% 39

SX8-

182

4,8 -

33%

-9% 1

SX8-

172

1% 75

SX8-

173

19% 106

102

SX8-

156

4,7 -

34%

-11% 1

SX8-

174

1% 74

SX8-

178

2% 78% 74% 38

SX8-

159

4,7 -

34%

-11% 1

WE320

0% 73

SX8-

179

-2% 70% 67% 32

SX8-

201

4,7 -

35%

-12% 1

SX8-

194

-1% 72

SX8-

225

5% 83% 79% 42

SX8-

223

4,6 -

35%

-13% 1

SX8-

123

-2% 71

SX8-

226

21% 109

105

Page 14 of 19

301

Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity of Hybrid Varieties

of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European Journal of Applied Sciences, 10(3). 300-

317.

URL: http://dx.doi.org/10.14738/aivp.103.12364

N°: number, G1: Group 1; G2: Group 2; G3: Group 3; GY: grain yield; SD1: WE3205; SD7: SR21; SD8: Bondofa; SD9: Komsaya

MAZ-20 4,6 -

36%

8% -14% 1

SX8-

126

-5% 66

SX8-

229

11%

54% 51% 20

SX8-

212

4,5 -

37%

9% 7% -15% 1

SX8-

138

-5% 64

SX8-

231

0% 73% 70% 35

SX8-

183

4,5 -

37%

9% 7% -15% 1

SX8-

211

-6% 64

SX8-

239

7% 85% 82% 44

SX8-

162

4,3 -

40%

5% 3% -18% 1

SX8-

209

-6% 63

SX8-

145

4,3 -

40%

4% 2% -19% 1

SX8-

146

-6% 62

SX8-

199

4,2 -

41%

2% 0% -20% 2

SX8-

200

-7% 62

SX8-

218

4,1 -

42%

1% -1% -21% 2

SX8-

122

-7% 62

SD7 4,1 -

42%

0% -2% -22% 2

SX8-

187

-7% 61

SX8-

207

4,1

42%

0% -2% -22% 2

SX8-

197

-8% 60

SX8-

230

4,0 -

44%

-3% -4% -24% 2

SX8-

151

10%

SX8-

233

4,0 -

44%

-4% -5% -25% 2

MAZ-21 6,

10%

Page 15 of 19

European Journal of Applied Sciences – Vol. 10, No. 3

Publication Date: June 25, 2022

DOI:10.14738/aivp.103.12364.

Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity

of Hybrid Varieties of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European

Journal of Applied Sciences, 10(3). 300-317.

Services for Science and Education – United Kingdom

Following the different analyses of the yield comparison test of the varieties studied against the

controls, 15 hybrids were identified on the basis of their grain yields (Table IX).

Table IX: Varieties with the best potential yields compared to control varieties

SD1: control variety WE3205; SD7: control variety SR21; SD8: control variety Bondofa; SD9:

control variety Komsaya

DISCUSSION

Agro-morphological parameters such as emergence percentage, plant height, ear insertion

height, lodging susceptibility, breakage susceptibility, yield, and plant cycles discriminate most

between the varieties evaluated. These parameters have been used by several authors to

characterize or evaluate local and improved maize varieties [18]; [20]; [27]. In addition to these

parameters, diseases such as helminthosporiosis and maize streak observed on maize hybrid

plants were also used to evaluate the performance of the varieties. All these parameters were

used to classify the varieties into three groups. The hybrids in group 1 are those least adapted

to the climatic conditions of the Banfora area in southwestern Burkina Faso. Thus, these hybrids

have the lowest emergence percentages (33%) and have a relatively long cycle with lower plant

height (0.8 m) and produce low yields (2 t/ha). These low emergence percentages could be due

to the relatively high temperature (27°C) at sowing time. This temperature is higher than the

optimum for maize germination which is 21-22°C [19]; [23]. This temperature does not seem

to favor the germination of these hybrid maize varieties. These results are comparable to those

of Nyembo et al. (2014) who obtained germination rates of 22% to 66% with 17 maize varieties

submitted for evaluation under similar temperature conditions (on average 27°C) [20].

However, in our study, some hybrids showed good emergence percentages reaching 100%.

This difference could be explained by the size of the genetic material used. Indeed, the number

of varieties used (128 varieties) in this study is larger than the one used by Nyembo et al., 2014;

Code Grain Color Type Grain Grouped GY (t/ha) SD1 SD7 SD8 SD9

SX8-121 Yellow Dent/Flint 3 8,7 21% 110% 106% 64%

SX8-226 White Flint/Dent 3 8,6 21% 109% 105% 63%

SX8-173 Yellow Dent/Flint 3 8,5 19% 106% 102% 60%

SX8-136 Yellow Flint/Dent 3 8,4 17% 103% 99% 58%

SX8-198 Yellow Dent/Flint 2 8 11% 93% 90% 50%

SX8-233 White Flint/Dent 2 7,9 11% 92% 89% 50%

SX8-128 Yellow Flint/Dent 2 7,7 8% 87% 83% 45%

SX8-129 Yellow Flint/Dent 3 7,7 7% 86% 82% 45%

SX8-239 White Dent/Flint 3 7,7 7% 85% 82% 44%

SX8-195 Yellow Flint/Dent 2 7,6 7% 85% 81% 44%

SX8-210 Yellow Flint/Dent 2 7,6 6% 84% 81% 43%

SX8-225 White Flint/Dent 3 7,5 5% 83% 79% 42%

SX8-238 White Dent/Flint 2 7,5 4% 81% 78% 41%

SX8-155 Yellow Flint 3 7,4 3% 79% 76% 39%

SX8-169 Yellow Flint 3 7,4 3% 78% 75% 39%

SX8-171 Yellow Flint/Dent 2 7,3 3% 78% 75% 39%

Page 16 of 19

301

Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity of Hybrid Varieties

of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European Journal of Applied Sciences, 10(3). 300-

317.

URL: http://dx.doi.org/10.14738/aivp.103.12364

this could express a greater genetic variability [20]. In addition, the small plant height of the

varieties in this group, the cycle length as well as the low yield would be related to growth

delays. Indeed, the plants of these hybrids were spindly, stunted or showed tillers. This

abnormal vegetative development had a negative impact on ear formation and consequently on

the yield of these varieties. Thus, under certain climatic conditions, apical dominance is reduced

and stems can develop from the axillary buds at the base of the stem. These secondary stems

usually do not bear ears, but most often a panicle with a few grains [2]. A hormonal disorder

linked to climatic conditions, in particular strong solar radiation, would be at the origin of this

phenomenon in the most sensitive genotypes [2]. It should be noted that maize generally grown

in the tropics does not till and has only one main stalk. However, some highland maize varieties

in Mexico have very high tillering [22]. Thus, the tillering of some of the tested hybrids would

be related to the Mexican origin of the plant material. Most of the tillers were unproductive

because they presented a panicle and an ear without grains. This tillering could be an advantage

for fodder production.

The hybrids in groups 2 and 3 showed good vegetative growth and acceptable productivity

compared to the control varieties. The plants of the hybrids in these groups had average heights

of 1.5 m and 1.8 m respectively; average yields of 6.2 and 7.5 t/ha respectively. However, these

hybrids had a relatively short cycle and were more susceptible to lodging and breakage. In

general, the plants of these hybrids were tolerant to helminthosporiosis and maize streak. In

addition, it was found that taller plants were more susceptible to lodging and breakage. These

results are comparable to those obtained by Moussa et al. (2018) on an evaluation of the agro- morphological performance of local and improved maize varieties in southwestern Niger [18].

This could justify the high susceptibility of group 2 and 3 hybrids to lodging and breakage.

However, some hybrid varieties, notably SX8-170, SX8-174, SX8-225, SX8-226, SX8-231, SX8-

239, were not insensitive to lodging and breakage although their plants were also very tall. The

tolerance of these varieties to lodging and breakage could be due to the presence of anchor

roots observed in these hybrids, which impose a certain resistance to these two phenomena

because these anchor roots help to consolidate the fixation of the plant to the soil. Indeed,

Liebhargr and Murdock (1965) have shown that root lodging is due to the poor development

of anchor roots, which are in smaller numbers and cover a smaller area of the soil under severe

potassium deficiency [13]. Soil and fertilizer potassium significantly reduce lodging and

increase anchorage strength [1]; [28]. The intensive crop-type mineral fertilization applied to

the plants during the experiment could therefore account for the development of anchoring

roots and the resistance to lodging and breakage observed in the hybrid varieties SX8-170, SX8-

174, SX8-225, SX8-226, SX8-231, and SX8-239.

As for productivity, 25 varieties with significantly higher grain yields than the control varieties

were identified. Despite this performance, the yields of some varieties remain below their

potential. Indeed, the yields of the control varieties SD8 and SD8 averaged 4.2 t/ha and 5.3 t/ha

respectively, which is far below the yields mentioned in the national catalogue of varieties in

2014. Nyembo et al (2014) obtained yields of 8-15 t/ha on improved varieties under evaluation

in the Democratic Republic of Congo [20]. Compared to these results, this general decrease in

yield of the hybrid varieties studied could be justified by the infection of the plants by diseases

and armyworm attacks during the experiment. Indeed, armyworm attacks were observed 14

days after sowing and were frequent until harvest. Similar cases were observed by Elola (2012)

Page 17 of 19

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European Journal of Applied Sciences (EJAS) Vol. 10, Issue 3, June-2022

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who noted a general low yield of the hybrids tested at the INERA Farako-Bâ station, due to a

lack of rainfall during the trial period [10]. Elola (2012) obtained a yield of 1.10 t/ha with the

control variety SD8 and a yield varying between 0.07 and 6.03 t/ha for the hybrids evaluated

by this author [10]. Nevertheless, despite the pressure of disease infections and armyworm

attacks, some of the varieties evaluated expressed significantly higher yields than the local

controls. The best varieties identified were characterized by advantage grain yields compared

to the local control varieties, up to 5.5 t/ha, and were genotype groups 2 and 3. Compared to

the control variety WE3205, which is resistant to water stress and insect attack, none of the

varieties evaluated showed a grain yield superiority of up to 25%. But, the tested varieties SX8-

121 and SX8-226 with 8.7 t/ha and 8.6 t/ha respectively showed yields more than 20% higher

than WE3205. The varieties SX8-173 and SX8-136 yielded 8.5 t/ha and 8.4 t/ha respectively,

19% and 17% higher than WE3205. These four varieties, SX8-121, SX8-226, SX8-173 and SX8-

136, showed an average yield gain of 1.4 t/ha compared to the control WE3205. These yield

gains over the control varieties are similar to those obtained by Elola (2012) [10].

In sum, the identified varieties namely SX8-121, SX8-226, SX8-173 and SX8-136, in addition to

being distinct from the control varieties, combine high values for parameters as growth, yield

and lodging resistance score parameters. Based on the good combination of growth

parameters, yield and lodging resistance, Nyembo et al., (2014) recommended improved

varieties with grain yields similar to local controls (8 to 15 t/ha) for production under climatic

conditions in Lubumbashi, Democratic Republic of Congo [20]. This is because these agronomic

traits are important in germplasm selection programs [19]. According to Moussa et al. (2018),

the positive correlation between yield and growth parameters is a good indicator for direct

selection of high-yielding genotypes [18]. The same authors indicate that relatively short-cycle

varieties with individuals with more developed vegetative traits produce better yields. In

addition, armyworm and disease attack showed that the varieties tested have good tolerance

to these biotic stresses. These results come at a time when the armyworm threat is becoming

an increasing scourge of maize cultivation in Burkina Faso. According to Nyembo (2010), the

use of improved varieties is a response to the problem of low yields and abiotic stresses that

can lead to drastic reductions in maize production [19].

Page 18 of 19

303

Banhoro, A., Nana, R., Kone, H. T., Sory, A., Ouedraogo, M. H., Sawadogo, M., & Tinland, B. (2022). Evaluation of the Productivity of Hybrid Varieties

of Maize (Zea Mays L.) Under Tropical Climatic Conditions in the Sudanian Zone of Burkina Faso. European Journal of Applied Sciences, 10(3). 300-

317.

URL: http://dx.doi.org/10.14738/aivp.103.12364

CONCLUSION

The evaluation based on the yield, growth parameters and diseases of the 128 hybrid varieties

made it possible to group the varieties evaluated into three homogeneous groups. The most

discriminating variables used to form the groups were: percentage of emergence, yield, plant

height, ear insertion level, susceptibility to lodging and breakage, number of days to 50% male

flowering, number of days to 50% female flowering and number of days to plant maturity. A

total of 25 varieties with the best grain yields compared to the control varieties were identified.

These varieties, with an average height of 1.7 m, had yields above 7 t/ha. They were

characterized by good emergence percentage, good resistance to lodging and breakage; and

recorded tolerance ratings to helminthosporiosis and maize streak. These varieties can be

recommended for farmer extension in the Banfora area following additional multi-year studies.

They can also be recommended for growing areas with climatic conditions similar to those of

Banfora, where annual rainfall varies between 900 mm and 1200 mm with an average

temperature of 27°C. In view of the grain yields of these varieties despite armyworm attacks,

these varieties can be included in armyworm control programs.

As a result of this study, multi-location and multi-year testing of the 25 best varieties identified

can be recommended in order to test their grain yield stability in the three climatic zones of

Burkina Faso. This stability study will allow to propose to farmer hybrid varieties with good

yield potential adapted to the climatic conditions of Burkina Faso.

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