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Discoveries in Agriculture and Food Sciences - Vol. 11, No. 1

Publication Date: February 25, 2023

DOI:10.14738/dafs.111.14079.

Kebede, B. K., & Mengistu, S. (2023). Review Article: Agro Morphological Trait Evaluation of Garlic (Allium Sativum L.) Response

to Fertilizer. Discoveries in Agriculture and Food Sciences, 11(1). 9-17.

Services for Science and Education – United Kingdom

Review Article: Agro Morphological Trait Evaluation of Garlic

(Allium Sativum L.) Response to Fertilizer

Bekele Kindie Kebede

Ethiopian Biodiversity Institute Harar, Biodiversity Center, Harar, Ethiopia.

Solomon Mengistu

Ethiopian Biodiversity Institute Harar, Biodiversity Center, Harar, Ethiopia.

Abstract

As a review, garlic (Allium sativum L.) is one of the main allium vegetable crops

known through worldwide with respect to its production and economic value.

Garlic belongs to the genus Allium and family Alliaceous. Garlic has high

morphological diversity and adaptable to different agro-climatic regions and

environments. Morphological and agronomic variations in characteristics of garlic

are shown such as color of the bulb, size of the bulb, plant height, number of cloves,

size of the cloves, days to harvesting, resistance to storage capacity, dormancy and

adaptation to agro-climatic conditions. Farmers endeavor to produce high yield and

good quality garlic for consumption and economic value. Correlation between some

quantitative traits of garlic showed the positive and significant correlation with

yield and leaf length. All yield and yield-related traits were significantly influenced

through the interaction of cultivar and nitrogen fertilizer except leaf length, leaf

number per plant, bulb length and sizes of bulbs and cloves of different categories

that were significantly influenced either by both cultivar and nitrogen or one of

these.

Keywords: Diversity, Morphological traits, Growth, Yield, Fertilizer and Nitrogen.

INTRODUCTION

Garlic (Allium sativum L.) is one of the main vegetable crops known worldwide with respect to

its production and economic value. Garlic is a species-rich and taxonomically complicated

genus with more than 750 species. It is an important vegetable crop for its culinary, religious,

grown and medicinal purposes [10], [32]. Garlic is the most widely produced for fresh market,

dehydrated as an ingredient for food processing, essential oil, oil macerate and powder. Garlic

has constituted significant amounts of element such as Ca, P and K, and their leaves sources of

proteins, vitamins and contains antibiotics like garlicin and allistatin [16]. The principal

conservation of gene bank is to maintain genetic diversity active and reduce the loss of genetic

diversity of crop and plant species. Plants cannot be conserved as seeds because of their

unmanageable nature and clonally propagated are traditionally conserved [19]. Phenotypic

variability in the gene banks should be calculated in order to allow effective use of accession

collection and studies on the agro-morphological characterization of cultivars [37].

Morphological traits diversity of crop genetic resources plays a significant role in the breeding

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Discoveries in Agriculture and Food Sciences (DAFS) Vol 11, Issue 1, February- 2023

Services for Science and Education – United Kingdom

programs. Identifying appropriate indices for selecting garlic varieties and understanding the

variation between accessions can be improve the efficiency of breeding programs [43].

Generally, the garlic is an important bulb crops produced for home consumption as a flavor,

medicinal value and source of income in Ethiopia [12]. It grows mainly in the mid-altitudes and

highlands of the country. Garlic is one of the high-value vegetable crops produced in rotation

with pulses during the cold season [11]. Lack of improved high yielding varieties, low soil

fertility, inappropriate agronomic practices and lack of improved postharvest technologies are

among the well-known factors for limited productivity of garlic [13], [28]. Bulb yield and days

to maturity of garlic were disposed to environmental changes resulting in variable yield due to

the significant effect of genotype-by-environment interaction [38]. Lack of appropriate variety

and plant population greatly affects garlic growth, yield and quality [12]. There are local

improved garlic varieties under cultivation in the country. Varieties of garlic may differ in root

architecture; foliage and a cultivar perform differently under different agro-climatic conditions

[35]. This review was to evaluate the growth and yield related traits which could be suitable

descriptors in future clonal selection programs regarding to agromorphological traits.

BOTANICAL AND AGROMORPHOLOGICAL TRAITS DESCRIPTION GARLIC (ALLIUM

SATIVUM L)

Botanically, garlic belongs to the genus Allium, family Alliaceous, which includes important

vegetable crops such as onion (Allium cepa), leek (A. ameloprisum) and shallots (A. asacloncum).

Garlic is propagated asexually and shows highly morphological diversity among cultivars.

These diversity traits have a wide range of adaptations to different environments and agro- ecological zones. Garlic plants have thin tape-shaped leaves up to 30 cm long like that of onions.

The roots have reached up to 50 cm depth and more. The bulbs and heads are white skinned

which divided into certain types of sections called cloves and each bulb could have 6 up to 12

cloves covered by a white or reddish papery layer [16].

The sexual propagation of garlic has been facilitated the exchange of genetic traits from one

genotype to others to improve garlic cultivars in classical breeding [18]. It does not produce

true seed but propagates through planting cloves. The select seed bulbs should be large,

smooth, fresh, and free from disease. Garlic bulb is the best for planting garlic because larger

cloves yield larger size and mature bulbs at harvesting time. To plant the garlic properly dig a

hole, place the unpeeled clove gently into the hole with the pointed side up the stem end down

and cover the clove with smoothed soil and the setting of cloves has been in an upright position

to make sure a straight neck [26].

PRODUCTION AND PRODUCTIVITY OF GARLIC IN ETHIOPIA

Garlic is one of the important agricultural bulb vegetables grown and seasoning vegetables

mainly used for flavoring and has many traditional and modern medicinal properties [1]. The

small growers of garlic in the highlands are grown through traditionally faulty agricultural

practices and the yields are low [6], [5]. Generally, garlic is adapted to cool climates and the

amount of rainfall during the growing period (4 to 6 months) with 600 mm to 700 mm. It should

not be planted at altitudes below 2000 m. a. s. l. The optimum temperature for growing garlic

lies between 12°C and 24°C. It is essential to select land with high fertility and apply

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Kebede, B. K., & Mengistu, S. (2023). Review Article: Agro Morphological Trait Evaluation of Garlic (Allium Sativum L.) Response to Fertilizer.

Discoveries in Agriculture and Food Sciences, 11(1). 9-17.

URL: http://dx.doi.org/10.14738/dafs.111.14079

considerable quantities of manure or fertilizers to obtain good yields of garlic bulbs [6]. Under

the comparison of countries in garlic production, Ethiopia has been placed the 12th in the world

ranking [7].

ECOLOGY AND METHODS OF GARLIC PRODUCTION

Garlic has a wide area of adaptation and cultivation throughout the world. The ecological

requirement of garlic is a mild winter season which has certain rainfall with a sunny dry

summer season which is good for garlic production but very high humidity and rainfall are

unfavorable to vegetative bulb formation and reduce its production [4]. The productivity of

garlic in many parts of the world is low due to genetic variability, ago ecological and

environmental factors affecting the quantity and quality of yield and yield-related traits. Yield

and quality will vary with climate, altitude, soil, pH, cultural practices and the variety of garlic

[30]. It is advisable to conversation with local growers who have experience growing garlic and

experiment with different cultural practices and varieties. Water stress during the growing

season can cause bulbs to be smaller and to cause a multiple stem disorder [2], [36]. The ‘seeds’

needed per hectare are very variable as the cloves of different species vary greatly in size. The

upper 15-20 cm of the soil surface should be always moist, but not wet, because most of the

root system will be grown in this depth [41].

Development and Growthing of Garlic

Garlic is a cool season growth plant that all vitality and leaf growth when the temperatures are

cool and the day is short. When the temperature becomes warm and the day is lengthen the

growthing of garlic plant stop making leaves and activates to form bulbs. The life cycle of the

plant under goes successive stages of growth and development the dormancy of mature cloves,

induced through the temperature of 25-30 0C is eliminated most quickly at 6-7 0C vegetative

growth is optimal at 18-20 0C [27]. When 12-14 leaves have been produced, bulb swelling is

induced at a temperature below 20 0C. The total growing period varies from 4 months to 9

months. Garlic cloves require a period of 6-8 weeks of cool weather after planting in low winter

temperatures. The clove will swell considerably forming a globular bulb with many fine roots

and a pair of intertwined leaves will emerge from the terminal end of the bulb. Leaf

development also will accelerate with flat and dark green leaves on stems reaching a height of

30 cm or more. As temperatures rise and day length increases, bulb formation begins. The

results showed the following development stages in garlic: Sprouting: from sowing to 20-30

days, adventitious roots, leaf emergence, and total soluble carbohydrate assimilation in seed

cloves are observed. Shoot growth: from the end of sprouting until 140 days after sowing.

Translocation of photosynthesis to the bulb begins afterwards. Bulb growth: during the

inductive stage from sprouting, no increase in dry weight of total soluble carbohydrates can be

observed up to 90 days [22]. Garlic is a species of vegetative propagation, showing high

morphological diversity and has specific adaptations to different agro-climatic regions and

environments [31]. Extensive morphological and agronomic variations in the characteristics of

garlic are shown such as color of the bulb, size of the bulb, plant height, number, of cloves, size

of the cloves, days to harvesting, resistance to storage capacity, dormancy and adaptation to

agro-climatic conditions [9].