2(2)33-43

Abstract
Detailed information on the genetic diversity between maize germplasm
(Zea mays L.) is useful for their systematic and efficient use in breeding
programs. Fourteen early maize genotypes were studied to assess their
performance and genotypic diversity at Doti, Nepal in 2015. Days to
tasseling, days to silking, plant height, ear height, ear length, ear diameter
and grain yield were significant among genotypes. Genotype SO3TEY-PO-
BM, COMPOL-NIOBP and ACROSS-99402 were found higher yielder with
earlier maturity. Days to tasseling (0.85), days to silking (0.82), plant height
(0.79), ear length (0.71) and ear diameter (0.66) were found highly heritable
traits. Grain yield (0.39) and ear height (0.47) medium and remaining traits
showed low heritability. High PCV was observed for grain yield (35.10%),
number of plants/plot (34.46%), tesseling silking interval (26.85%),
harvested ears/plot (24.45%) and husk cover rating (22.85%) where other
traits showed medium to low PCV. Grain yield showed high GCV (21.96%),
ear height and husk cover had medium and remaining traits showed low
GCV (<10%). Plant height (r₌0.498), harvested plants/plot (r₌0.412),
harvested ear/plot (r₌0.762), ear length (r₌0.472) and ear diameter (r₌0.470)
showed significant positive correlation with grain yield. The yield can be
improved if selection applied in favor of those yield components.

ISSN : 2580-2410
eISSN : 2580-2119

Agronomic performance and genotypic diversity for
morphological traits among early maize genotypes

Bhim Nath Adhikari1, Jiban Shrestha2, Bishal Dhakal1, Bishnu Prasad Joshi1,

& Naba Raj Bhatta1

1Regional Agriculture Research Station (RARS), Dipal, Doti, NARC, Nepal
2National Commercial Agriculture Research Program, Pakhribas, Dhankuta, Nepal

Introduction

Maize (Zea mays L.) is second important crop after rice in Nepal. It is cultivated in
891583 ha with 2503 kg/ha national productivity (MOAD, 2017). The majority of the maize
area lies in the mid hills across the country where it is the first principal staple food and feed
crop and produce about 70% of national maize production. Therefore maize can be
considered as source of livelihood for hilly farmers. It is a traditional crop cultivated on
slopping upland terraces (bariland) in the hills under rainfed condition during the summer on
which fingermillet is relayed in majority, however sole maize was dominantly followed by
wheat. Hilly areas of western Nepal is mostly food deficit, drought prone areas where annual

OPEN ACCESS International Journal of Applied Biology

Keyword
Maize
Variability
Heritability
Genetic advance
Correlation

Article History
Received 30 October 2018
Accepted 25 December 2018

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International Journal of Applied Biology, p-ISSN : 2580-2410 e-ISSN : 2580-2119.
Journal homepage : http://journal.unhas.ac.id/index.php/ijoab

International Journal of Applied Biology, 2(2), 2018

average rainfall is about 1000 mm and rainfall distribution is erratic and unpredictable. Lower
productivity of maize is associated with lack of suitable varieties for stress environments,
inadequate variety in the existing system, lack of agricultural inputs like irrigation, fertilizers
etc. Early maturing maize will also ensure for timely wheat sowing in maize-wheat system
which may lead proper germination and initial growth of wheat because wheat is grown on
residual moisture and if sown late germination and growth may be adversely affected due to
lack of moisture in bariland farming. In addition early maturing maize also compete less with
fingermillet for sunlight, nutrients and moisture than full season maize in maize/millet relay
cropping with ultimately support to increase fingermillet yield. Thus improved maize
genotypes with early maturity and high yield, tolerant to drought and better fit into existing
system will increase and stabilize yield of maize, fingermillet and wheat on bariland farming
system of hilly areas.

Variability is the differences between individuals in a population due to genetic
composition and growing environment (Sumanth et al., 2017). The existence of variability is
utmost role as success of any plant breeding program depends on the genetic variability and
selection skill of plant breeder (Adhikari et al., 2018). Selection is only effective if the parent
population have significant amount of variability. Phenotypic coefficient of variation (PCV)
and genotypic coefficient of variation (GCV) provides insight information on magnitude of
variability in a population and heritability shows the component of a character transmitted to
future generations (Pal et al., 2016; Girma et al., 2018) Further, heritability coupled with
genetic advance shows the expected genetic gain in next generation (Shukla et al., 2006). In
addition, correlation between yield and yield attributing traits are prime important for
indirect selection for those traits which have high heritability and closely associated to
contributes to improve yield (Aditya & Bhartiya, 2013). Therefore, the study was under taken
to identify suitable early maturing genotypes and to know the information on variability,
heritability, genetic advance and traits correlation on tested materials to utilize it on future
maize breeding activity which aim to develop suitable genotype for rainfed bariland farming
of mid hills areas of Nepal.

Materials and Methods
Experimental Location

The experiment was conducted at Regional Agricultural Research Station, Dipayal,
Doti. Geographically, it is situated at 80° 55' east longitude and 29° 15' north latitude and the
altitude of this station is 510 masl (RARS, 2015). The climate is sub tropical, generally
monsoon starts late in July and it is erratic with average annual rainfall of about 900mm.
Experimental field soil was shallow in depth and porous, sandy loam, slightly acidic with pH
5.5-6.0, low in nitrogen and organic matter i.e. 1-2% and 0.6 % respectively and the water
holding capacity of the soil is very low (RARS, 2015).

Genotypes

The experiment was carried out with fourteen different early maize genotypes in
which 13 were received from National Maize Research Program (NMRP), Rampur and
Farmer’s variety was collected from Dipayal, Doti. The tested genotype were: Earlymid
Katamani, Rajahar Local, S97TEYGHAYB(3), POP-445/POP-446, COMPOL-NIBP, RC/POOL-17,
S03TEY/LM, Arun-4 (standard check variety), Farmer’s variety (local check variety),
ZM621/POOL-15, EEYC1, SO3TEY-LN/PP, SO3TEY-PO-BM and Across-99402.

International Journal of Applied Biology, 2(2), 2018

Experimental Design and cultural practices
The experiment was planted on 2nd week of June in Randomized Complete Block

Design (RCBD) with three replications. Along with FYM @ 10 t/ha chemical fertilizers at the
rate of 60:60:40 N P2O5 K2O kg/ha in the form of Urea, DAP and Murate of Potash were applied
during final land preparation. Top dressing was done by 60 kg N/ha in two splits, i.e. 30 kg
N/ha at knee high stage and 30 kg N/ha at just before tasseling stage. Individual plot size was
3m × 3m (4 rows of 3m long). Seed was shown @ 2 seeds/hills in 75 cm apart rows by
maintaining 25 cm between hill to hill in a row. Thinning was done to maintain plant
population after 3 weeks of germination. Intercultural operations were done as per
recommendation of National Maize Research Program.

Data measurement

Days to tasseling, days to silking, number of plants harvested, number of cob
harvested, field weight were taken from central 2 rows from each plot. Five plants form
central rows randomly selected and plant height, ear height, ear length, ear diameter
recorded and mean values was taken for analysis. Husk cover rating was taken as 1-5 scale
where 1 is good and 5 is poor. After taking field weight, composite grains from five randomly
selected ears prepared and moisture reading taken for thrice and mean was used for yield
estimation. Grain yield was estimated at 15% moisture and 80% shelling coefficient by below
formula which was also adopted by Carangal et al. (1971) and Shrestha et al. (2018).

Grain yield (
kg
ha

) =
F. W. ( kgplot) × (100 − HMP) × S × 10000

(100 − DMP) × NPA

Where,
F.W. = Fresh weight of ear in kg per plot at harvest
HMP = Grain moisture percentage at harvest
DMP = Desired moisture percentage, i.e. 15%
NPA = Net harvest plot area, m2
S = Shelling coefficient, i.e. 0.8

Data analysis

Analysis of variance and correlation among traits were done by using Genstat 18th
edition at 0.05 level of significance. Likewise significance of correlation coefficient was done
as proposed by Kothari (2004). The phenotypic and genotypic variances were computed
according to Falconer (1981). Broad sense heritability was calculated using formula suggested
by Allard (1960) and categorized as low (0-0.3), moderate (0.30-0.6) and high (>0.6). The
estimates of genetic advance were obtained at 5% selection intensity and categorized as high
(>20%), medium (10-20%) and low (<10%) as suggested by Johnson et al. (1955). Coefficient
of genotypic and phenotypic variation were also categorized as high (>20%), medium (10-
20%) and low (<10%) as proposed by Sivasubramanian and Madhavamenon (1973).

International Journal of Applied Biology, 2(2), 2018

Results and Discussion
Analysis of Variance

The analysis of variance for 10 quantitative characters showed significant differences
among the evaluated genotypes for days to tasseling, days to silking, plant height, ear height,
ear length, ear diameter and grain yield. However, differences were not significant for
tasseling silking interval days, number of harvested plants/plot, number of harvested
cobs/plot and husk cover rating (Table 1 and 2). Statistical traits indicated the existence of
inherent genetic variation among tested genotypes for those traits. Thus there is scope to
enhance genetic yield potential through selection and hybridization. Existence of significant
genetic variability among maize genotypes for yield and major yield attributing traits were
reported by Vashistha et al. (2013), Ogunniyan and Olakojo (2014), Pahadi and Sapkota
(2016), Bhusal et al. (2017), Kandel et al. (2018) and Sharma et al., (2018). Prasai et al. (2015)
also reported genetic variability on early maize. Similarly, Shrestha (2014) observed
morphological variation in maize inbred lines in Chitwan, Nepal.

Agronomic performance

Agronomic performance observed on yield and yield attributing characters were
summarized and presented in Table 1 and 2.

Days to tasseling, silking and tasseling silking interval

Genotypic differences were observed significant for both days to silking and tasseling
but the interval between silking and tasseling remained statistically non-significant. The
silking tasseling intervals remained 2-3 days for all tested genotypes. Farmers variety
observed earliest in tasseling and silking took 37 and 40 days respectively which was followed
by S97TEYGHAYB(3) and Arun-4 both took 45 and 48 days respectively for tasseling and
silking. Genotype S03TEY/LM observed late took 51 days for tasseling and 53 days for silking.
This observation clearly indicated that farmer’s variety is extra early and could be one of the
parents for maize hybridization program to develop early maturing variety. Significant
difference among tested maize genotypes for days to tasseling and silking were previously
reported by (Vashistha et al., 2013; Prasai et al., 2015; Sharma et al., 2018; Bhusal et al., 2017).

Plant and ear height

Significant differences for plant and ear height observed indicated the existence of
genetic variability among genotypes kept under study. Rajahar Local was the tallest genotype
in plant height (287 cm) and ear height (126 cm) whereas farmers' variety was observed as
dwarf genotypes. Standard check variety (Arun-4) and ZM621/POOL-15 were found medium
in plant and ear height. In favor of present study, genotypic variation on plant and ear height
were previously reported by (Ogunniyan and Olakojo, 2014; Parsai et al., 2015; Sharma et al.,
2018).

Plant and ear harvested

Tested genotypes were not differed statistically for number of plants and ear
harvested per unit area. Mean harvested plants and ear were found 14 and 16 respectively.
Similar result on harvested plant and ears on early maturing maize were reported by Katuwal
et al. (2017).

International Journal of Applied Biology, 2(2), 2018

Ear length, diameter and Husk cover rating
Genotypic differences were observed for ear length and diameter but rating based on

husk cover remained at par between genotypes. Across-99402 was observed highest ear
length and farmer’s variety was shortest ear length. Likewise, genotype ZM 621/POOL-15 was
found having highest ear diameter while farmer’s variety was lowest. Husk cover rating was
observed 2-3 for all genotypes. Genetic difference on ear length and diameter were also
reported by (Vashistha et al., 2013; Pahadi & Sapkota, 2016).

Grain Yield

The grain yield was found statistically significant indicating the existence of genetic
variability on yield potential on the tested genotypes. Higher yielder genotypes observed
were SO3TEY-PO-BM, COMPOL-NIOBP, ACROSS-99402 could be selected as promising
genotypes for early maturing groups or may be used as a parent in maize breeding program
to develop early maturing maize varieties. Likewise, farmer’s variety was poor yielder but due
to its early maturing character it can also be used as a parent for the purpose. Genetic
variability on maize genotypes was reported by many authors including (Vashistha et al.,
2013; Bhusal et al., 2017; Katuwal et al., 2017).

Genetic parameter estimation

Estimated genetic parameter such as the phenotypic coefficient of variation (PCV), the
genotypic coefficient of variation (GCV), broad sense heritability, and genetic advance as
percent of means are presented in Table 3. Yield and yield attributing traits under study
showed higher phenotypic coefficient of variance than genotypic coefficient of variance
indicated high environmental influence on the expression of these trait, however, as
compared with others, less environmental influence was observed for days to silking,
tasseling and plant height. Similar results were presented by (Pahadi and Sapkota, 2017; Bisen
et al., 2018; Sharma et al., 2018). High PCV was observed for grain yield, number of
plants/plot, tesseling silking interval, harvested ears/plot and husk cover rating where as
remaining traits showed medium to low PCV. Similarly high GCV was estimated for grain yield,
medium for ear height and husk cover rating and remaining traits showed low GCV. In line
with this findings high PCV and GCV for grain yield was also reported by (Ogunniyan and
Olakayo, 2014; Bhusal et al., 2017; Bisen et al., 2018; Sharma et al., 2018).

Table 1. Mean performance of yield attributing traits on maize

SN Genotype DT DS TSI PH EH
1 Early Mid Katamani 50fg 52def 2.33 250def 100abcd
2 Rajahar Local Variety 48bcdf 50bcde 2.67 287g 126d
3 S97TEYGHAYB(3) 45b 48b 3.00 211ab 75a
4 POP-445/POP-446 46bcde 49bcd 3.67 222bc 78ab
5 COMPOL-NIBP 50fg 53ef 3.00 232bcd 77ab
6 RC/POOL-17 47bcdef 50bcd 2.33 251def 111cd
7 S03TEY/LM 51g 53f 2.33 256ef 107cd
8 Arun-4 45bc 48bc 3.00 245cde 106cd
9 Farmer’s Variety 37a 40a 2.67 195a 75a

10 ZM621/POOL-15 48cef 51cdef 3.00 241cde 97abc
11 EEYC1 45bcd 48b 2.67 271fg 101abcd
12 SO3TEY-LN/PP 49fg 52def 2.33 253def 96abc

International Journal of Applied Biology, 2(2), 2018

13 SO3TEY-PO-BM 49fg 52def 3.00 273fg 102bcd
14 ACROSS-99402 49fg 51def 2.33 233bcd 90abc

Mean 47 50 2.74 244 96
SEM 1.17 1.24 0.57 9.97 11.14
P value <.001 <.001 0.534 <.001 0.002
CV% 3.0 3.1 25.9 5.0 14.2
LSD (0.05) 2.4 2.56 20.48 22.9

Means followed by a superscripted common letter with in a column are not significantly different from each other at P ≤ 0.05.
DT= Days to tasseling, DS= Days to silking, TSI= Tasseling silking interval, PH= Plant height (cm), EH=Ear height (cm)

Due to the lower differences estimated between PCV and GCV selection based on

phenotypic performance for days to tasseling, silking and plant height would be effective to
bring about considerable genetic improvement on the tested maize population for these
traits but agronomic performance can’t improve by providing favorable environment without
selection. Traits showing higher difference between GCV and PCV indicated that these traits
are more influenced by growing environment thus selection is not effective on those traits,
can be maintained by providing optimum growing environment.

Table 2. Mean performance of grain yield and yield attributing traits on maize

SN Genotypes P/P E/P EL ED HC GY
1 Early Mid Katamani 14 16 14.00bc 4.20bc 3.00 2945abcd
2 Rajahar Local Variety 18 17 13.33b 4.17b 2.67 3013abcd
3 S97TEYGHAYB(3) 19 17 14.33bcd 4.37bcde 2.67 3109bcd
4 POP-445/POP-446 11 13 14.00bc 4.40bcde 2.67 2225ab
5 COMPOL-NIBP 14 18 14.67bcd 4.60ef 2.33 4179d
6 RC/POOL-17 15 15 13.67b 4.40bcde 3.00 2299ab
7 S03TEY/LM 9 17 14.67bcd 4.53ef 3.00 3409bcd
8 Arun-4 15 14 14.00bc 4.20bcd 2.67 2834abcd
9 Farmer’s Variety 10 11 10.00a 3.87a 2.00 1409a

10 ZM621/POOL-15 14 11 14.33bcd 4.77f 2.33 2392abc
11 EEYC1 18 18 14.33bcd 4.50cef 2.00 3880bcd
12 SO3TEY-LN/PP 14 18 14.00bc 4.37bcde 2.00 3522bcd
13 SO3TEY-PO-BM 14 17 15.33cd 4.60ef 2.00 4333d
14 ACROSS-99402 18 18 15.67d 4.63ef 2.33 3976cd

Mean 14 16 14.02 4.40 2.48 3108.93
SEM 3.91 2.97 0.64 0.13 0.41 695.1
P value 0.314 0.273 <.001 <0.001 0.108 0.01
CV% 33.2 23.3 5.6 3.6 20.4 27.4
LSD (0.05) 1.32 0.26 1428.8

Means followed by a superscripted common letter with in a column are not significantly different from each other at P ≤ 0.05.
P/P= Number of harvested plants/plot, E/P= Number of harvested ears/plot, EL= Ear length (cm), ED= Ear diameter (cm)
HC= Husk cover rating in 1-5 scale, GY= Grain Yield kg/ha

Among the studied traits broad sense heritability ranged from 0.04 (TSI) to 0.85 days

to tasseling. Heritability is grouped as low (<0.3), moderate (0.3-0.6) and high (>0.6). Based
on this category days to tasseling, days to silking, plant height, ear length and ear diameter
were found highly heritable traits. Grain yield and ear height medium and remaining traits
showed low heritability. High heritability for days to tasseling, days to silking, plant height,

International Journal of Applied Biology, 2(2), 2018

ear length and ear diameter and high to medium for grain yield were also reported by
(Vasistha et al., 2013; Bhusal et al., 2017; Sharma et al., 2018). Medium heritability for grain
yield may be due to the influence of the environment on the yield as it is polygenic trait. Low
heritability estimates might be due to the variation of environmental component involved for
those traits and vice versa. High heritability estimated traits indicated a high response to
selection for particular traits.

Estimated heritability is not very much useful because it includes the effect of both
additive and non additive gene. The genetic advance with heritability is therefore a useful
indicator to achieve expected result on the trait of interest of a population after selection.
Further, genetic advance in percentage of mean give more precise result in comparison to
only genetic advance. Genetic advance as percent mean was categorized as low (0-10%),
moderate (10-20%) and high (≥20%). In the present study high genetic advance as percent of
mean was estimated for grain yield. Days to tasseling, days to silking, plant height, ear height
and ear length showed medium and remaining traits showed low genetic advance as percent
of mean. In conformity to this findings, high genetic advance for grain yield and medium to
low for other traits also reported by (Vasistha et al., 2013; Ogunniyan and Olakayo, 2014;
Sharma et al., 2018). High to medium heritability coupled with medium to low genetic gain
indicate observed characters among tested genotypes governed by non-additive gene action
and thus heterosis breeding, family selection and progeny testing methods is used for
improvement on such traits.

Table 3. Phenotypic (Vp) and genotypic variance (Vg), phenotypic coefficient (PCV) and

genotypic coefficient of variance (GCV), heritability (broad sense), genetic advance
(GA) and genetic advance as percent of mean (GAM) for observed traits

SN Traits Treatment Error Vg Vp Hbs GCV PCV GA GAM

1 DT 36.26 2.06 11.40 13.46 0.85 7.17 7.79 6.40 13.60
2 DS 34.65 2.33 10.77 13.11 0.82 6.59 7.27 5.28 10.60
3 TSI 0.57 0.50 0.02 0.53 0.04 5.52 26.85 0.05 2.01
4 PH 1830.05 148.96 560.36 709.32 0.79 9.69 10.90 37.35 15.29
5 EH 690.50 186.18 168.11 354.29 0.47 13.53 19.65 15.85 16.55
6 P/P 28.34 23.01 1.77 24.79 0.07 9.22 34.46 0.63 4.38
7 E/P 17.31 13.28 1.34 14.62 0.09 7.41 24.45 0.62 3.98

10 EL 5.15 0.62 1.51 2.13 0.71 8.76 10.42 1.83 13.08
11 ED 0.17 0.02 0.05 0.07 0.66 4.92 6.08 0.31 7.08
12 HC 0.45 0.25 0.06 0.32 0.20 10.23 22.85 0.20 8.13
15 GY 2123268 724770 466166 1190936 0.39 21.96 35.10 758.22 24.39

DT= Days to tasseling, DS= Days to silking, TSI= Tasseling silking interval, PH= Plant height (cm), EH=Ear height (cm), P/P=
Number of harvested plants/plot, E/P= Number of harvested ears/plot, EL= Ear length (cm), ED= Ear diameter (cm), HC= Husk
cover rating in 1-5 scale, GY= Grain Yield kg/ha, Vg=genotypic variance, Vp=phenotypic variance, Hbs= Heritability broad
sense, GCV= Genotypic coefficient of variation, PCV= Phenotypic coefficient of variation, GA= Genetic advance, GAM= Genetic
advance as percent of mean.

Correlation study

Days to tasseling and silking sowed significant positive correlation. These traits both
showed significant positive association plant height, ear length and ear diameter indicated
that plant height, ear length and ear diameter can be simultaneously increase while selecting
relatively late plants. In line with this findings (Ogunniyan and Olakaago, 2014; Bhusal et al.,
2017) reported significant positive correlation between days to tasseling, silking and plant

International Journal of Applied Biology, 2(2), 2018

height. Further, in conformity to present study (Pahadi and Sapkota, 2016; Khan et al., 2018)
also reported significant positive correlation for days to silking with ear length and diameter,
however Khan et al. (2018) reported non-significant positive relationship between days to
tasseling with ear length and diameter. Similarly, significant positive relationship with days to
siliking and non significant positive with days to tasseling towards ear length and ear
diamenter was also reported by Sharma et al. (2018). Further plant height have shown
significant positive correlation with ear height indicated that ear height can be altered
simultaneously while selecting plants on the basis of height. In addition, plant height has
shown significant positive association with number of ear harvested showed that ear
prolificacy is higher in tall plants. Very similar findings on relationship between plant height,
ear height and number of harvested plants were also reoprted by (Ogunniyan and Olakaago,
2014; Bhusal et al., 2017; Sharma et al., 2018). Harvested plants/plot showed significant
association with harvested ear/plot. Likewise number of harvested ear showed significant
positive association with ear length and ear diameter. Significant positive relation was also
observed between ear length and ear diameter. These findings were also partially supported
by (Pahadi and Sapkota, 2016; Bhusal et al., 2017; Sharma et al., 2018).

In the present study non significant positive correlation observed between plant
height and ear length (r₌0.304), plant height and ear diameter (r₌0.285), plant height and
number of plants/plot (r₌0.267). Similarly ear height showed non significant positive
correlation with plants/plot (r₌0.227) and husk cover rating (r₌0.22). Further both silking and
tasseling days shown non significant positive association with husk cover rating and number
of ears/plot. Number of harvested pods/plant showed non significant positive correlation
with ear length (r₌0.285) and ear diameter (r₌0.304). On the other side, non significant
negative correlation observed between husk cover and ear diameter, husk cover and number
of harvested ear/plot, husk cover and number of harvest plants/plot and both days to
tasseling and silking with harvested plants/plot.

Table 4. Phenotypic correlation coefficient of grain yield and yield attributing traits on early

maize genotypes.
Traits DT DS PH EH P/P E/P HC EL ED

DT 1
DS 0.981** 1

PH 0.355* 0.351* 1

EH 0.162 0.165 0.733** 1

P/P -0.078 -0.038 0.267 0.227 1

E/P 0.282 0.257 0.378* 0.146 0.587** 1

HC 0.225 0.219 0.018 0.220 -0.108 -0.147 1

EL 0.701** 0.718** 0.304 0.071 0.285 0.360* 0.108 1

ED 0.467** 0.492** 0.285 0.037 0.304 0.316* -0.150 0.684** 1

GY 0.300 0.274 0.498** 0.158 0.412** 0.762** -0.264 0.472** 0.470**
* and ** significant at P₌0.05 and P₌ 0.01 level of significance respectively.
DT= Days to tasseling, DS= Days to silking, TSI= Tasseling silking interval, PH= Plant height (cm), EH=Ear height (cm), P/P=
Number of harvested plants/plot, E/P= Number of harvested ears/plot, EL= Ear length (cm), ED= Ear diameter (cm), HC= Husk
cover rating in 1-5 scale, GY= Grain Yield kg/ha

Grain yield had shown significant positive association for plant height, number of

harvested plants/plot, number of harvested ears/plot, ear length and ear diameter indicated
that selection in favour of these traits will improve grain yield on early maturing maize

International Journal of Applied Biology, 2(2), 2018

genotypes. These findings were in conformity with previous reporting by (Bhusal et al., 2017;
Ogunniyan and Olakaago, 2014; Khan et al., 2018; Sharma et al., 2018). In addition non
significant correlation was observed for days to tasseling (r₌0.3), days to silking (r₌0.274), ear
height (r₌0.158) and husk cover rating (r₌-0.264)with grain yield.

Conclusions

This study identified maize genotypes SO3TEY-PO-BM, COMPOL-NIOBP and ACROSS-
99402 suitable for rainfed bariland farming based on the maturity and yield performance.
Dipal local was found extra early, thus it could be one of the parents for maize breeding
program for developing early maturing maize varieties. This study indicated the genetic
variability on the studied genotypes mostly inherited by non additive gene action and direct
selection is not fruitful, so hybridization followed by selection is recommended for
improvement. As plant height, number of harvested pods/plot, number of harvested
ears/plot, ear length and ear diameter were found significantly positively correlated with
maize grain yield thus selection applied in favour these traits will simultaneously improve
maze yield of selected plants.

Acknowledgments

The authors would like to thank National Maize Research Program, Rampur for
providing testing genotypes and technical support. We would like to thank technical officer
Mr. MB Chodaro and technical assistant staffs of Regional Agricultural Research Station, Doti,
Nepal for their support on conducting research activities.

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