DEBRE BERHAN UNIVERSITY

COLLEE OF AGRICULTURE AND NATURAL RESOURCES SCIENCES

DEPARTMENT OF PLANT SCIENCE

REIVEW ON EFFECT OF TEMPERATURE ON GROWTH, YIELD AND

QUALITY OF TOMATO (Lycopersicana esculent Mill)

PREPARED BY: -

MESERET LINGEREW

ID NO: DBUR/1923/09

ADVISOR: - Dr. BEZUAYEHU

A Seminar Paper

SUBMITTED TO DEPARTMENT OF PLANT SCIENCE, COLLEGE OF AGRICULTURE AND

NATURAL RESOURCE, RESEARCH DEBRE BERHAN UNIVERSITY IN FULFILMENTS OF THE
REQUIREMENTS FOR THE COURSE OF SENIOR SEMINAR (PLSC 3104

January, 2019

DBU Ethiopia
 ACKNOWLEDGMENTS

Above all I would like to thank my God for his presence with me in all ups and downs. I express
my deep sense of gratitude to my advisor Dr. Bezuayehu for their guidance, valuable comments
and suggestions that enabled me to complete this senior seminar. My special thanks also extend
to the department of plant science.

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 LIST OF ABBREVIATION

LAR Leaf area ratio

RGR Relative growth rate (RGR)

NAR Net assimilation rate

ULR Unit leaf rate

LWR Leaf weight ratio

SRA Specific leaf area

EARO Ethiopian Agricultural Research Organization

MARC Melkassa agricultural research center

FAO Food agricultural organization

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 TABLE OF CONTENTS
CONTENTS......................................................................................................Page
LIST OF ABBREVIATION……………………………………………………......................... 2
TABLE OF CONTENTS………………………………………………………………………. 4
ACKNOWLEDGMENTS………………………………………………………………………
Error! Bookmark not defined.
SYNOPSIS……………………………………………………………………………………….
Error! Bookmark not defined.
1. INTRODUCTION……………………………………………………………………………. 5
2. OVER VIEW OF GROWTH AND YIELD OF TOMATOES FRUIT……………………
Error! Bookmark not defined.
2.1. General Effect of Temperature on Growth and Yield of Tomato Fruit……………… 7
2.2. Photosynthesis of Tomato Fruits………………………………………………………... 9
2.3. Fruit Growth………………………………………………………………………………
10
2.4. Flowering and Fruit Set of Tomato……………………………………………………...
11
2.5. Quality of Tomato………………………………………………………………………. 11
3. SUMMARY AND CONCLUSION………………………………………………………… 13
4. PROSPECT………………………………………………………………………………….. 14
REFERENCES………………………………………………………………………………….15

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 1. INTRODUCTION

Tomato (Lycopersicana esculent Mill) is one of the most important vegetable in world wide. It
also belongs to the solanaceae family; these families also include other well-known species, such
as Potato, Tobacco, Peppers and Eggplant As it is relatively short duration crop and gives high
yield, economical attractive and their cultivation is increased daily. (Adams et al.2001). The
importance of tomato was widely accepted and commonly used in varieties of dishes as raw,
cooked or processed products more than any other vegetable. But there is no definite time
recorded regarding to the introduction of tomatoes in Ethiopia (Lemma, 2002).However, cherry
types has been growing for long time around big cities and in small gardens. Recently the crop
has expanded to commercial production for home use, export and processing industries. The bulk
of fresh market tomato is produced by small scale farmers. Farmers are interested in tomato
production more than any other vegetable for its multiple harvests, as result in high profit per
unit area like in many countries. The other importance of this vegetables are contributed to a
health, well-balanced diet, as a salad rich in minerals, vitamins, essential amino acid, sugar and
dietary fibers, generate cash in small scale farmers and provides employment in production and
Processing industries (Lemma, 2002 and EIAR, 2002) .It is self-pollinated crop but occasionally
out crossing under high temperature because the growth of the stigma beyond the anther cone.
However, such floral exertion has not been observed in studied with tomato lines in the warmer
season of the year at Melkassa in Rift valley (MARC, 2002 as cited by Lemma
2002)Temperature significantly affects the partitioning of assimilates between the vegetative and
generative parts. At high temperature truss appear faster (Adams et al., 2001), initially there are
more fruit on plants, may cause delay in the newly growth fruit and might even load to flower or
root abortion and developing and flowering trusses are weaker sink than fruiting trusses (The
most common one currently reviewed in the production of tomato blossom end rot, blotch
ripening, cat face, cracking, puffiness and sun card. Those are affecting the growth and yield of
tomato plants, but they generally decrease the number of fruit per plant (Lemma, 2002).

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1.2 Objective

 To review temperature related tomato research achievements, identify the gaps and give
future line of work for improving yield of tomato fruits.

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 2. LITERATURE REVIEW

2.1 TEMPERATURE EFFECT ON GROWTH, YIELD AND QUALITY OF TOMATO

FRUIT

Growth is increasing the dry matter of the plants. All anther plants and tomatoes including their
reproductive structures can be broken down into photometric primarily made up of a node and
internodes leaf (Fitter and Hay, 2002). Any confusion between growth and development can be
minimized by use of the term expansion or extension rather than growth when referring to
increasing in dimension organ of plants which are not necessarily associated with to increasing
dry matter. The rates of growth of plants are determined by temperature, unless the plants are
exposed to stress, such as drought and nutrient deficiency. The temperature relations of the
different processes are not identical (Adams et al 2002). The growth of young vegetative
tomatoes plants can be characterized by their relative growth rate (RGR).The relative growth rate
describes the rate increasing in plants mass per unit plant mass already present. It can be
explained by different leaf area per unit plant mass (LAR); leaf area ratio or by differences, in
the rate of increasing in plant mass per unit leaf area (NAR); net assimilation rate or unit leaf rate
(ULR), As relative growth rate (RGR) is the product of leaf area ratio (LAR) and net
assimilation rate (NAR) (Hunt, 1990).Leaf area ratio (LAR) the product of specific Leaf area
(SLA; total leaf area per unit leaf mass) and leaf weight ratio (LWR); leaf biomass per unit total
plant mass). Net assimilation rate (NAR) is the proportional to net Leaf photosynthetic rate.
Growth rate of tomato fruit is function of time after flowering (day after a thesis or as function of
development stage (time from flowering until final Harvesting of tomato fruit) (Hunt,
1990). Tomato yield is not isolated characteristic and depends on the growth of the whole plant.
If the tomato plant does not grow well then it will never give a high yield. Therefore yield is
determined by the interaction between plant morphology, physiology and growth conditions.
Decreasing and increasing the temperature will have an influence on different aspects of tomato
growth (e.g., biomass production and development (e.g., leaf and truss appearance, fruit growth
period) (Poleg and Heuvelink, 2005)

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2.1. Effect of Temperature on Growth and Yield of Tomato Fruit

The effect of temperature on growth and yield of tomato (Lycopesicon esculents Mill) are
reviewed with special emphasis on cultivar differences. When the temperature below the level
chilling injury occurs and when the temperature above the level wilting finally delaying occurs.
Temperature has a large effect on all aspect of growth .Leaf and truss initiation rates decrease
linearly with decreasing temperature. Although these rates may be different for different
cultivars their response to temperature is the same (Burgs man et al., 1992) Young plants grown
at not optimal temperatures produce thicker leaves, so they intercept less light, therefore have
lower relative growth rate. There was an interaction between temperature and cultivar for relative
growth rate and relative traits in crop producing fruit, this is aspect is less important as most of
the light is intercepted any ways. At sub- optimal temperature fruit set is reduced the result of
poorer pollen quality. The period between anthesis and ripening of the fruit is increasing and as
the growth rate of fruit at certain development is independent of temperature, fruits become
larger at sub-optimal temperature .Higher temperature leads to an increase in early yield, at the
cost of vegetative growth, but may also cause delay in later trusses. Total yield over a whole
season might be equal at lower temperature, but higher tomato price early in the season do not
make it economically profitable and reduce the temperature the green house (Cradle et al.,
1997). At high temperature, the relative growth rate (RGR) is initially, but decrease rapidly with
time ( on to genetic decrease);while, for lower temperatures ,the relative growth rate (RGR) is
initially low, but the decline is also lower than at the higher temperatures(Adams et
al.,1997),because faster internal shading at high temperatures. Therefore several scientist have
chosen to compare RGR at fixed plant weight (Lind hout et al., 1991) over weight interval
(Heuvelink, 1989), or at the stage of development (Venema et al., 1999). In the unfavorable
temperature range the relative growth rate (RGR) of tomatoes plants were reduced at lower
average temperatures (Hoek et al., 1993; Venema et al., 1999) as well as when plants are grown
any lower night temperature (Franco, 1990; Nieuwhof et al., 1991).Tomato plants that are grown
under day temperature higher than night temperature regime are also reduced in height, due to
shorter internodes (De conning, 1988; Heuvelink, 1989; Longton et al., 1997). The effect of
temperature regime is well-known in many horticultural crops as the “DIF EFFECT “(the
different between day and night temperature effects ;( Erwin et al., 1989). The decreasing in

8
relative growth rate at no optimal night temperature is caused by decreasing in leaf assimilation
rate (LAR), while net assimilation rate (NAR) is not affected by night temperature (Franco,
1990; Nieuwhof et al., 1991).The decreasing in net assimilation rate (NAR), which is small
compared to the decreasing in leaf assimilation rate (LAR) at lower temperature could be
confirmed by the lower rate of net photosynthesis. Photosynthesis decreased when day
temperature (DT) was reduced from 25oc to 16oc(Venema et al., 1999).Photosynthesis decreased
under lower night temperature, due to increased leaf thickness. Different temperature during
vegetative growth influence the rate of development and timing to first flowering (Grimstad,
1995;Sauser, 1998).Other research indicated that the duration, magnitude and timing of short
term temperature pulses during the growing season influenced fruit development (Adams and
Valdes, 2002)

Tomato yield is determined primarily by the amount of intercepted light (Newton et al., 1999)
and assimilate partitioning (Ho, 1996). The effect of temperature on the partitioning is probably
not directly affect (Heuvelink, 1995), but on indirect effect of temperature on the rate of
development, fruit set and abortion. At higher temperature truss appear faster (Nieuwhof et al.,
1997; Adams et al., 2001) and there are more fruit on the plants at higher temperature. This will
growth expense of vegetative growth but may also cause delaying the growth newly fruit set and
might even lead to flower of fruit abortion (De konning, 1989) as developing and trusses are
weaker than fruiting trusses. Plant production at higher temperature fruit set was poor and many
fruit are parthenocarpic, resulting in lower tomato production compared to tomato plant which
growth under normal condition of temperature (Adams et al., 2001).When the temperature fall
below the level where fruit set is affected, yield are lower than at temperatures where fruit set is
not effected (Nieuwhof et al., 1997; Adams et al., 2001). At lower temperature fruit are
parthenocarpic, small, and hard and had no marketable value (Adams et al., 2001). In lower
temperature plants produce thicker leaves, resulting in lower total light interception, also the rate
of photosynthesis is slightly lower although this effect maybe counterfeited by the lower
respiration rate in fruits Producing crop, these effects are likely to be less important as most light
is intercepted. However at higher temperature the initial fruit load is high, as there are more
trusses on each plant (Ploeg and Heuvelnk, 2005).

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2.2. Photosynthesis of Tomato Fruits

The photosynthesis rate of tomato decreased significantly with high and low temperature at both
pre-flowering and flowering stage. High temperature can cause the declines in photosynthesis
rate have some things to do with stomata factor and also have some things non-stomata factors.
They also the synthesis of chlorophyll content is blocked, the content of carotenoids is decreased
and the ratio between various pigments is also changed which has directly effect on the
absorption of light energy (Kitano et al., 1998; Araki et al., 2000; Adams et al., 2001). Tomato
growth under high and low temperature produced lower fruit yield (Ho, 1996; Adams et al.,
2001).

2.3. Fruit Growth

The period between anthesis and maturity of a fruit decrease with increasing average temperature
between 14oc and 26oc (De konning, 1994; Adams et al., 2001).This effect is greater at lower
temperature (De konning, 2000).When progress to maturity is plotted against average
temperature (AT), linear response is found (Adams et al., 2001).However, temperature
sensitivity is not the same over the whole fruit growth period. Higher temperature during an
thesis shortened the time to maturity (De konning, 1994). At this period the relative growth rate
of tomato fruit is high and in this interval, cell division and elongation take place. Then there is a
period during high temperature hardly increases the development rate of tomato fruit (Adams et
al., 2001).When cell elongation takes place, relative growth rate steadily decreased, also when
the fruit close to maturity, increasing temperature. Again large influence on decreasing the time
to maturity of the fruit (De konning, 1994; Adams et al., 2001) in that period, the relative growth
rate is almost zero and it is likely that processes involved in the ripening of tomato are affected
by the temperature.The relationship between growth and development stage of tomato fruit
calculated as the time after anthesis divided by the time from flowering until maturity is almost
independent of temperature between 17oc and 25oc.However, longer growth period with
decreasing temperature between 17oc and 26oc cause fruit to become large when growth at lower
temperature (De konning ,1994;Newton et al.,1999;Adams et al.,2001).When temperature was
increased for short time during the growth period of tomato fruit, the absolute fruit growth rate
increased (Pearce et al., 1993; Kitano et al., 1998).This increases could be achieved when only

10
the fruit were heated (Kitano etal., 1998; Araki et al., 2000; Adams et al., 2001). Thus
discrepancy exists between the long-term and short-term effect of temperature on fruit growth
rate. The difference between the short-term and long-term temperature response of fruit growth
could possible explained by accumulation the amount of enzymatic machinery responsible for
the up take processing of assimilates. The dry matter content of fruit increases slightly with
increasing temperature between 17oc and 23oc (De konning, 1994) therefore, have positive
influence on flavor. Consumer also preferred the flavor of tomato produced at 23oc compared to
tomato produced at 17oc (Buitelaar and Janse, 1990). Effect of high and low temperature at
different stages of tomatoes is different at immature stage highly sensitive to temperature
because the tomato fruit is immature to tolerate with high and low temperature. But after mature
and post-flowering stage less sensitive to high and low temperatures due to developed their organ
food production and adaptable with environmental conditions(Adams SR,et al 2001).

2.2. Effect of Temperature on Flowering and Fruit Set of Tomato

High and low temperatures affect the flowering and fruit set of tomato fruit. Low temperature
reduce the number of leaves, darkening of the leaf or stem tissues, damage fruit areas later wilt
and turn brown. It may difficult initially to determine whether the growing point has been killed
and damaged may evident on the day after the frost (Dicleman and Heuvelink, 1992). Low
temperature also reduce the rate leaf appearance, but does not reduce the time to first flowering
which is longer at lower temperatures (Hurd and Gravels, 1985) and heating the flower bud
hastens flower opening (Adams et al.,2001).Tomato plants are also susceptible to chilling injury
at temperature between 0oc and 5oc and it cause stunted growth, wilting, and surface pitting or
necrosis of foliage and increase susceptibility to disease (De konning, 1988), and low soil
temperature also stunt plant growth and prevent root development. Temperature below 10oc
during flowering can interfere with pollination and resulting in cat facing of fruit, but fruit set is
optimum between 18oc and 20oc(De konning,1994) the reducing of fruit set at lower or
higher temperature does the result of stigma level or ovule viability and poorer quality of pollen
(Picken,1990).

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2.3. Effect of Temperature on Quality of Tomato

Quality parameters of tomato fruits have been reported to be under genetic control and also
strongly determined by the environmental conditions present from a thesis to harvest. The effect
of climatic conditions and season on tomato quality and yield has been studied extensively
(Dorias m.et al.2001).even though the effect of light and temperature regimes on tomato yield
appears well established, (Adams et.al 2001) .the influence of these two parameters on tomato
quality is still a matter of considerable debate. This is, at least partly, due to a variety of reasons:
(i) parameters of tomato quality have often been related to me a climatic data over the entire
season or growing cycle, being then only slightly indicative of the climatic conditions that
actually occurred from an thesis to harvest; (ii) the source/sink balance has been reported to
influence tomato quality. (Bertin. N .et.al, 2001) and (iii) the response of tomato quality to
environmental conditions is cultivar dependent (Anza.m.et.al 2006) and also depends on fruit
position within the truss. (Gauiter.h.et.al 2005). Temperature also affects fruit quality, as
temperature has a direct influence on metabolism and, thus, affects cellular structure and other
components that determine fruit quality such as color, texture, size and organoleptic properties
(Dorais et al., 2001). Lower temperatures increase the time required for ripening and therefore
increase the size of fruits. However if the temperature is too low and fruit set is affected, the
number of “hollow” fruits is increased.

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 3. SUMMARY AND CONCLUSION

Tomato (Lycopersicum esculent Mill) is one of the most important vegetable in world wide. The
most widely accepted and commonly used in varieties of dishes as raw, cooked or processed
products more than any other vegetable. Farmers are interested in tomato production more than
any other vegetable for its multiple harvests, Tomato research program in Ethiopia was started in
the 1960s to address (solve) various production constraints .It is self-pollinated crop but
occasionally out crossing under high temperature because the growth of the stigma beyond the
anther cone. At high temperature truss appear faster and initially there are more fruit on plants,
this will grow expense of vegetative growth. As temperatures increase, fruit set is reduced as a
result of poorer pollen quality. The period between anthesis and ripening of the fruit increases
and, as the growth rate of the fruit at a certain developmental stage is independent of
temperature, fruits become larger at sub-optimal temperature. Higher temperature leads to an
increase in early yield, at the cost of vegetative growth, but may also cause a delay in later
trusses. Total yield over a whole season might be equal at lower temperatures, but higher tomato

13
prices early in the season do not make it economically profitable to reduce the temperature in the
greenhouse. Short-term effects might thus be different from long-term effects. Quality
parameters of tomato fruits have been reported to be under genetic control and environmental
conditions present from a thesis to harvest. In young, vegetative tomato plants growth is reduced
because the plants produce thicker leaves. In mature plants this aspect can be neglected as most
of the light is intercepted anyway. Early yield is affected by temperature because less assimilate
goes to fruits at lower temperatures, due to lower fruit and truss development rates early in the
season. But short-term temperature effects could be different from long-term temperature effects,
as a high initial fruit load might lead to a limited assimilate supply for developing trusses

4. PROSPECT
Even though industries are extended widely also the climatic change can also lead to increasing
temperature, optimum temperature is required to increase the production of tomato. Therefore all
possible adaptation strategies should be studied and adopted to improve tomato production
through the following;

 Research trials to evaluate response of the crop by using shade so as to reduce high
temperature exposure and water loss.
 Selecting or introducing best performing genotypes and make adaptation trial to different
agro climatic condition of the country.
 Researchers must look for alternatives source of variation in the temperature response to
tomato, wild relatives of the cultivated tomato provide.

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