an analysis of weather and wheat crop...
TRANSCRIPT
An Analysis of Weather and Wheat Crop Development in
Faisalabad (2012-2013)
Abstract
This study has been carried out in Faisalbad to investigate the impact of day to day changes in meteorological parameters like rainfall, air and soil temperature and soil moisture on plant growth and development during each phenological phase and on final yield of wheat crop. For this purpose, both meteorological and phenological data along with soil moisture data was collected from the experimental field of physiology section of Ayub Agriculture Research Institute Faisalabad. Besides this other important feature of under study crop i.e. sowing time, fertilizer, weeds removing operations and irrigation of crop have also been studied in the current report of season 2012-13. The wheat crop variety FSD-2008 accumulated 1785 heat units in 148 days during its life cycle from sowing to full maturity. The water requirement of crop was fulfilled by flood irrigation from sowing. Due to late sowing of wheat and unfavorable weather conditions i.e. rainfall in month of late February and April lead to less yield of wheat than normal yield because this rain causes disease in wheat crop. The standard yield of wheat crop is 2200 kg per acre.
Introduction
This study is based upon field observations of wheat crop by Regional Agromet Centre Faisalabad, cultivated in the experimental field of Ayub Agriculture research Institute, Faisalabad. In experimental field wheat crop variety FSD-2008 has been cultivated, recommended by AARI. This study will help in getting higher yield of wheat in Faisalabad region under various weather conditions.
Geographical Description and Climate of Pakistan and Central Punjab (Study Area)
Pakistan has a variable climate, ranging from arid (33-254mm annual rainfall) in the south to humid (1016-2032 mm annual rainfall), sub-humid (508-1016 mm annual rainfall) and semi-arid (254-508 mm annual rainfall) in the north. The Indus River that originates from the north with its tributaries irrigates the great plains of country. The area to the left of Indus is much affected by the neighbouring arid and hot Rajashthan Desert [1]. The agriculture in the major portion of upper half of the country which is mainly semi arid depends upon canal irrigation besides considerable intake of rain water also available due to monsoon weather systems. Winter rains occur due to westerly waves that penetrate into Pakistan from northwest. A narrow patch in the upper half of the country is sub-humid to humid, comprising of the mountainous to sub mountainous areas of Punjab and adjoining areas of Khyber Pakhtun Khaw, where heavy precipitation occurs both in summer and winter and agriculture is carried out without canal irrigation [2]. The study has been conducted for “Faisalabad District” with longitude 73.1 degree, latitude 31.43 degree and elevation of 184.5 m from mean sea level. The climate of central and southern Punjab possess the dry semi-arid agro-climatic characteristics but well managed canal irrigation system has placed it among the highly crop productive zones. Mainly summer monsoon produces rainfall and winter has a little contribution. The highest day temperatures termed as maximum temperature range in higher 40s degree Celsius from April to September except some occasional relief from monsoon rains and decreases the evaporation demand of the atmosphere too. Land surface near the study site consist of agriculture fields rotated among wheat, rice, cotton and many other seasonal crops. The study has been conducted at Regional Agromet Center (RAMC) is located at Ayub Agriculture Research Institute Jhang Road, Faisalabad. The longitude and latitude are 73.1˚ and 31.43˚ respectively. The elevation of RAMC from sea level is 184.5 m.
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Objective of the Study
• To analyze and study the impact of various meteorological parameters on crop growth
and its development. • To enhance the yield parameters of wheat crop in irrigated areas of Pakistan. • To investigate the water satisfaction sensitivity of crop in Faisalabad region. • To develop the relationship between weather parameters and crops life cycle. • To determine the onset of pests and diseases related to weather elements. • To get a step forward for formulation of yield estimation.
Review of Agriculture Production in Pakistan
Pakistan is an agrarian country whose population and economy directly or in directly (70 % directly and 16% indirectly) depends upon agriculture. Agriculture is the mainstay of Pakistan's economy. It accounts for 21% of the GDP and together with agro-based products fetches 80% of the country’s total export earnings. More than 48% of the labour force is engaged in this sector. Within the agricultural sector, the contribution from crop production is about 52 % while livestock contributes 44 %. Therefore any change in agricultural productivity creates a ripple effect throughout the rural population of Pakistan. Thus rapid agricultural growth can stimulate and sustain the pace of industrial growth, setting into motion a mutually reinforcing process of sustained economic growth (Economic Survey of Pakistan, 2009). In Pakistan Punjab is a revenue generator for the agricultural economy . Agriculture accounts 24% of GDP and Punjab has the largest contribution in the GDP among all provinces. The 48% of labor is engaged with agricultural sector and most of the land in Punjab is fertile. According to the Agriculture Punjab website “Punjab has 57% of the total cultivated and 69% of the total cropped area of Pakistan. It provides about 83% of cotton, 80% of wheat, 97% fine aromatic rice, 63% of sugarcane and 51% of maize to the national food production. Among fruits, mango accounts for 66%, citrus more than 95%, guava 82% and dates 34% of total national production of these fruits (Punjab Agriculture Department). Source: http://www.defence.pk/forums/national-political-issues/102679-punjab-door-revolution.html#ixzz2PWvbxY6r
Wheat Production in Pakistan
Wheat flour or “Atta” is the common food for most Pakistanis, supplying 72 % of caloric energy in the average diet. It is the main food cereal crop in Pakistan and is essentially better from nutritional point of view then most cereals and other foods. It is estimated that in our country wheat consumption per capita is 124 kg per year, which is the highest amount over the world (USDA Foreign Agriculture Service Report, 2010). The above fact reflects the importance of wheat crop for our country. Therefore every year variation in the total yield of wheat due to several factors including climate and weather variations directly affects the economy and social balance of the country. Wheat is a Rabi crop that is grown in the winter season. In Pakistan sowing of wheat takes place from October to December and harvesting during the month of March to May. In Punjab sowing time of wheat is November to December whereas harvesting period is March to April. Data, Materials and Methodology
For this purpose both meteorological and crop data were recorded during the crop season. In order to compile the data of each development stage, carefully and timely recording of different meteorological parameters were undertaking at 0300, 0900, and 1200 UTC. Crop data including phenological and soil moisture were collected according to World Meteorological Organization (WMO) recommended criteria.
Table 2-1: Observed Meteorological Parameters
1. Air Temperature (˚C)
2. Maximum & Minimum Temperature (˚C)
3. Soil Temperature (˚C)
4. Relative Humidity (%)
5. Precipitation (mm)
6. Pan Evaporation at 0300 & 1200UTC
7. Bright Sunshine Hours
8. Wind Speed (km/hour)
9. Wind Direction
10. Soil Moisture (%)
Table 2-2: Brief Summary of the Wheat Crop 1 Field size ½ acre
2 Crop variety FSD-2008
3 Date of Sowing 20-11-2011
4 Information about any disease/ pest
attack, -///
5 Pesticides and weedicides details (28-12-2012)
Exiel 300 ml per acre Buetrel super 300 per acre
6 Quantity of seed per acre 50kg
7 Row spacing 25cm
8 Schedule and quantity of dose of fertilizer a- DAP 2 bag/acre b- Urea 2 bag/acre
9 Type of irrigation Flood irrigation
10 Irrigation schedule
11-12-2012 14-01-2013 12-03-2013
11 Heat units consumed from sowing to full maturity
1785
12 Total days taken by the crop from sowing to full maturity
148
13 Date of harvesting 24-04-2013
14 Actual / Potential yield 1600 kg /acre
Phenology
A sound understanding of plant growth and development, Phenology of plant is an essential
element of efficient economic cotton management system. The impact of heat, drought, diseases,
insects, and weeds can be more accurately predicted with a clear picture of the relationship
between growth stage and plant response to stress. The optimum timing of fertilizer, irrigation,
herbicide, insecticide, and fungicide applications are also best determined by crop growth or
phenological stage rather than calendar date.
Table 2-3: Phenological stages of wheat crop
1 Germination
2 Emergence
3 Third Leaf
4 Tillering
5 Shooting
6 Heading
7 Flowering
8 Milk Maturity
9 Wax Maturity
10 Full Maturity
Phenological Observations
Generally the field selected for Phenological observations should be of one hector size but in
this case area of field selected for observation was one and half acre and it was divided into 4
replications. Over all 10 plants were selected from each replication (pheno– phase trials). These
plants were tagged in a row in each replication. Thus Phenological observations were recorded
on 40 plants and continued throughout the period on the same plants.
Total number of plants in a particular Phenological phase at the same time was observed from
each replication on every Monday, Wednesday and Saturday and these observations were
recorded on the prescribed Performa. When 10% of the selected plants were in certain phase,
that particular phase was considered to be started. If 50% of the selected plants displayed a
certain phase, that phase was considered to be in full swing. Similarly, 75% occurrence of a
certain phase displayed by the selected plants was considered as completion of that particular
phase and next Phenological phase observations were started at their proper time. Thus next
phenological stage is not bound to appear after the completion of first one. It has been observed
that at a time two phenological phases exist too.
Impact of Meteorological Parameters on Wheat Crop
Wheat variety FSD-2008 is one of the most productive and suitable wheat variety cultivated in
Punjab. Normally the wheat crop takes 100-120 days to be fully matured. Normally the crop is
cultivated in the start of November up to the end of December. In order to investigate the chief
causes about variation in the crop’s growth, development and yield related to varying weather
conditions and some other factors during each Phenological stages of wheat crop is studied as
follow
2.3.1 Rainfall and Wheat Crop Growth during Rabi Season in Faisalabad
Rainfall is one of the most important factor that affect annual wheat production in Pakistan.
Annual variation in rain and snowfall over plains and hills of the country also casuses the proper
supply of canal irrigation water. In time or effective rainfall i.e. before sowing and shooting to
grain formation stage is necessary input in yield production, but with suitable intervals in
required amount of the Phenological phase before full maturity contributes to normal or above
normal yield of the crop as continuous rainy and moist atmosphere does not suit normal growth
to wheat crop. In the same way, rain after sowing and before germination and at the time of full
maturity negatively affect crop growth and ultimately reduce the yield.
2.5 5.911
19.1 22 21.5
0
16.4
3.2
54.3
1.9
19
0
10
20
30
40
50
60
Nov Dec Jan Feb Mar Apr
Rai
nfal
l (m
m)
Rainfall during Rabi season 2012-13
Normal Actual
Irrigated Water during Crop Growth (2011-2012)
The wheat crop was irrigated three times during the entire season before full maturity. First
irrigation was made to the wheat crop 20 days later after sowing.
Air Temperature and Wheat Crop Growth
Air temperature is most important climatic variable that affects plant life. The growth of higher
plant is restricted to a temperature between 0 and 60 ˚C whereas crop plants are further restricted
to a narrower range of 10 to 40 ˚C. However each species and variety of plants and each age
group of plants has its own upper and lower limits. Beyond these limits, a plant becomes
considerably damaged and may even be killed. It is therefore the amplitude of variations in
temperature, rather than its mean value, that is more important to plant growth
(Agrometeorology; Harpal S. Mavi, Graeme J. Tupper).
Reasons for low and variable cotton yields are associated with extreme of temperature
(Oosterhuis, 1977). Yield and fiber characteristics respond to variations of daily mean and
amplitude of temperature ( Liakatas, Roussopoulos, and Whittington, 1988). Mean temperature
reduction improves yield comoponents, but high temperature, particularly high day temperature,
increase fiber length, uniformity, and strength. Large daily temperature amplitude produces an
intermediate number of flowers and the lowest retention percentage. An adverse effect of low
minimum temperature on lint and fiber property was also observed (Agrometeorology; Harpal S.
Mavi, Graeme J. Tupper). Detail of Mean Monthly Air Temperature, Monthly Mean Maximum and
Minimum Temperature and Absolute Maximum and Minimum Temperature are presented in Table-
7 along with Normals
051015202530
Nov Dec Jan Feb Mar Apr
Tem
pera
ture
(˚C)
Monthly Mean Temperture during Rabi season 2012‐13
Normal Actual
0
10
20
30
40
Nov Dec Jan Feb Mar Apr
Tempe
ratur (˚C)
Mean Max. Temperature during Rabi seanson 2012‐13
Normal Actual
0
5
10
15
20
25
Nov Dec Jan Feb Mar Apr
Tempe
rature (˚C )
Mean Min. Temperature during Rabi season 2012‐13
Normal Actual
Mean monthly temperature during Rabi season 2012-13 at RAMC. Faisalabad Month Monthly Mean
(C) Monthly Mean
Max. (C)
Monthly Mean Min.
( C)
Absolute Max. ( C)
Absolute Min. ( C)
Nov 19.3 (18.8)
27.3 (27.4)
11.3 (10.3)
31.0 (31.4)
6.7 (6.0)
Dec 13.7 (13.5)
20.6 (21.6)
6.6 (5.4)
28.1 (25.6)
3.0 (2.2)
Jan 11.6 (11.8)
18.8 (19.4)
4.4 (4.3)
24.7 (23.1)
-0.5 (08)
Feb 15.1 (14.4)
21.0 (21.8)
9.1 (6.9)
25.4 (26.8)
5.2 (2.0)
Mar 21.2 (19.3)
28.8 (26.5)
13.6 (12.2)
33.6 (32.1)
8.8 (6.3)
Apr 27.1 (25.8)
34.4 (33.7)
19.8 (18.0)
38.0 (40.3)
14.4 (12.4)
Soil Moisture Observations during Crop Growth
The soil moisture plays a vital role during crop’s life. Variation in soil moisture during crop’s life especially at the initial stages and at full maturity stage plays major role in the net crop’s yield. The soil samples are taken on 7th, 17th and 27th of each month, however next day the soil samples also taken if some anomalous event occurred in any month in four replications at 5, 10, 20, 30, 40, 50, 70, 90 and 110 cm depths. During this crop, soil samples were taken on Different days as mention in Table 4 below, with the help of augar and then weighed and dried in the oven for about 8 hours. Thus soil moisture present in the soil was calculated by the difference of wet and dry weights of soil. Moisture contents of the soil varied by the dry and wet spells throughout the season. These fluctuations were more prominent in the shallow layers of the soil. After each effective irrigation or rain the moisture level increased in the shallow layers as compared to deep layers of the soil followed by somewhat dry spell, the soil moisture slightly decreased in shallow layers.
Soil moisture (%) at different meteorological stages.
Depth
(cm)
26/11/2012 5/12/2012 04/01/2012 25/01/2013 5/3/2013 25/3/2013 15/04/2013
05 10.3 8.5 7.7 15.5 15.7 13.1 14.1
10 10.9 9.7 8.3 13.6 13.8 11.3 11.9
20 11.1 9.7 8.7 12.5 13.3 11.6 11.2
30 10.7 10.2 9.4 13.2 13.6 11.7 12.0
40 11.6 10.5 9.8 13.4 15.0 12.0 14.3
50 12.3 11.2 10.4 13.3 12.9 12.3 13.6
70 12.5 11.8 11.0 13.4 12.1 13.2 13.4
Soil Temperature and Crop Growth
Soil temperature plays an important role in crop growing period, right from the germination to
maturity. In comparison to air temperature, the amplitude of variation in soil temperature is
much more pronounced because of the varying characteristics, texture, composition, and organic
material of soil. Soil temperature influences the germination of seeds, the functional activity of
the root system, the incidence of plant diseases and the rate of plant growth. For each species, a
favorable for ion and water uptake. The daytime soil temperature is more important than the
nighttime temperature, because it is necessary to maintain the internal crop water status to match
the evaporation rate. (Agrometeorology; Harpal S. Mavi, Graeme J. Tupper). Temperatures
below 60°F are detrimental to germination, emergence, and seedling growth of cotton. During
the first 60 to 100 hours of germination, the radicle tip is easily damaged by chilling, lack of
oxygen in the soil, or too much moisture. If the tip is killed, a shallow system of secondary roots
develops that makes the plant more subject to moisture stress later in the season.
To measure soil temperature, the soil thermometers were installed at different depths to monitor
the thermal regime of the soil. The soil temperatures in 0C were observed and then recorded three
times a day at 0300, 0900 and 1200 UTC. The depth at which the soil temperatures were
observed on daily basis includes 5 cm, 10 cm, 20 cm, 30 cm, 50 cm and 100 cm depths. It was
observed that major root concentration centered between 30 cm to 40 cm depth which is just
close to the rooting depth of cotton in such soils. Soil temperature of different depths from
November, 2012 to April, 2013 is shown in Table given below.
90 13.0 12.5 10.9 13.6 13.6 12.8 13.6
Heat Units during Crop Growth
Heat units, Growing Degree Days, effective heat units or Growth units are a simple means of
relating plant growth, development, and maturity to air temperature. Heat units are often used in
agronomy, essentially to estimate or predict the length of the different phases of development in
crop plants (Bonhomme, 2000).
The heat units concept assumes a direct and linear relationship between plant growth and
temperature. It starts with the assumption that total plant growth is dependent on the total
amount of heat to which it is subjected during its life time. The heat units for a particular crop on
any day are the difference between the daily mean temperature (T) and the base temperature
(Tb) of the crop. Base temperature or Biological zero is the minimum temperature below which
no growth occurs. The base temperature or threshold varies with different plants, and for the
majority it ranges from 4.5 to 12.5°C.Here for wheat crop base temperature is 5°C. This concept
assumes that a given cultivar requires the same summation (k) of the daily mean temperature for
going one phenological stage to next stage, regardless of temperature distribution. Generally
only positive values above the biological zero (Tb) are considered. The period of negative value
is termed as “dormant” because crop does not grow under such conditions.
Month 5 cm 10 cm 20 cm 30 cm 50 cm 100 cm
Nov, 2012 18.6 18.8 19.4 19.9 21.1 23.6
Dec, 2012 13.2 13.4 14.0 14.7 16.3 19.4
Jan, 2013 11.2 11.3 11.7 12.2 13.3 16.2
Feb, 2013 14.7 14.8 14.8 14.9 15.3 16.5
Mar, 2013 21.6 21.6 21.0 20.6 20.3 19.5
Apr, 2013 27.1 27.0 26.9 26.3 25.4 23.6
Many methods to calculate the GDD are available in literature (Perry et al., 1997; Vittum,
Dethier, and Lesser, 1995). In this study the effective method has been used for deterimining
heat units which is represented by the following equation
GDD =∑ (T - Tb) = k if T > Tb ;
And
GDD = 0 = k if T < Tb
Where T = Mean daily temperature, Tb = Biological Zero (10°C),
K = Heat Unit
InterPhase period for wheat crop during 2012-13 and corresponding heat units at RAMC
Faisalabad observed at different phenological stages varies from phase to phase. Heat
unit requirements of different phases and cumulative heat units for the crop have been
worked out, are shown in Table-5. Total heat units consumed by the crop under
discussion were 1785 accumulated from germination to full maturity in 148 days. It
means that on average of 12 heat units were consumed by the crop per day.
Sr. No
Inter Phase
Period
No. of Days
Taken
Cumulative
Total
Degree Days
( T-5 °C)
Cumulative Frequency ∑(T-5°C)
1. Date of sowing
20-11-2012
2. Germination
28-11-2012 To
2-12-2012
05
05
55
55
3. Emergence
3-12-2012 To
16-12-2012
14
19
147
202
4. Third leaf
17-12-2012 To
4-01-2013
19
38
115
317
5. Tillering
5-01-2013 To
3-02-2013
30
68
222
539
6. Shooting
4-02-2013 To
24-02-2013
21
89
215
749
7. Heading
25-02-2013 To
10-03-2013
14
103
197
946
8. Flowering
11-03-2013 To
24-03-2013
14
117
227
1173
9. Milk maturity
25-03-2013 To
7-04-2013
14
131
220
1393
10. Wax maturity
8-04-2013 To
18-04-2013
11
142
248
1641
11. Full maturity
19-04-2013 To
24-04-2013
06
148
144
1785
12. Date of harvesting
24-04-2013
0200400600800100012001400160018002000
Cumalative Heat Units
Phenological Stages
Cummative Frequency of Growing Degree Days for Wheat Crop for 2012‐13
Sr. No
Phenological
Stage
Period
Days
Mean Temp. (°C)
Mean RH (%)
Mean
Windspeed Km per day
Pan Evaporation
ETo
Total
Bright Sunshine (Hours)
1. Sowing 20-11-2012
2. Germination 28-11-2012 To
2-12-2012
05
14.5 To
17.7
53
3.9
2.1
1.2
33.08
3. Emergence 3-12-2012 To
16-12-2012
14
12.8 To
16.3
60
3.2
1.8
1.1
75.75
4. Third leaf 17-12-2012 To
4-01-2013
19
9.5 To
15.8
66
3.8
1.9
1.0
62.25
5. Tillering 5-01-2013 To
3-02-2013
30
4.1 To
16.0
58
3.7
1.4
1.1
147.33
6. Shooting 4-02-2013 To
24-02-2013
21
12.6 To
17.0
66
5.1
1.9
1.6
93.33
7. Heading 25-02-2013 To
10-03-2013
14
15.0 To
23.0
57
5.6
2.4
2.5
108.42
8. Flowering 11-03-2013 To
24-03-2013
14
18.8 To
24.3
55
4.7
3.3
2.7
87.08
9. Milk maturity
25-03-2013 To
7-04-2013
14
20.3 To
25.1
47
4.8
4.1
3.5
113.58
10. Wax maturity
8-04-2013 To
18-04-2013
11
24.8 To
28.9
39
4.6
5.1
5.0
90.33
11. Full maturity 19-04-2013 To
24-04-2013
06
27.5 To
30.3
36
7.1
5.9
5.6
35.83
12. harvesting 24-04-2013
Other Meteorological Parameters
Monthly total precipitation (mm), means reference evapotranspiration (mmday-1), solar radiation (MJ m-2 day-1), wind speed ( km hour-1), wind direction and relative humidity (%) during the growth period are also given in the Table below. The frequency of occurance of very wet days with relative humidity greater than 80 is mentioned.
Month Rainfall (mm)
Rainy Days
Wind Speed
(km hr-1)
Wind Direction
Mean RH %
No of days with mean RH 80%
SunshineDuration
(hour)
ETo (mm
day-1)
Solar Radiation (MJ
)
Nov, 12 TR (2.5)
01 3.2 SW 57 0 191.7 1.1
Dec, 12 16.4 (8.6)
02 3.2 (1.4)
WNW (W)
65 (67)
8 164.1 (204.9)
1.1
Jan, 13 3.2 (11.5)
03 3.6 (2.3)
W (WNW)
62 (66)
4 153.6 (203.5)
1.2
Feb, 13 54.3 (20.1)
10 4.6 (3.0)
SSE (NW)
68 (61)
4 135.9 (203.0)
2.3
Mar, 13 1.9 (25.7)
03 5.2 (3.9)
SW (N)
54 (58)
0 248.3 (231.6)
3.0
Apr, 13 19.0 (16.9)
05 3.9 (3.6)
W (NNE)
52 (47)
0 251.8 (271.6)
5.0
Agro Meteorological Summary of Crop Cycle at Phenological Stages
Different meteorological parameters were recorded at various phases of wheat crop 2012-13. The temperature and relative humidity regime at different Phenological stages of wheat crop are discussed as under.
Emergence
Emergence phase was distinguished by the appearance of spike above the ground. When plant emergence stage was completed, the field was divided into four replications. The mean relative humidity during this phase was 60 %. Mean air temperature range during emergence was 12.8 -16.3 °C and however optimum ranges vary generally for all varieties of wheat crop.
Third Leaf
In the third leaf phase with 75 % occurrence, the mean relative humidity was 66 %, mean air temperature ranged between 9.5 -15.8 °C.
Tillering
This stage of crop growth started on 5-01-2013 and 75 % occurrence was completed on 30-01-2013. The mean air temperature range during this phenological stage was 4.1-16.0 °C and mean relative humidity was around 58 %.
Shooting
During this phase stem extension occurred in the crop. For the wheat crop, mean air temperature ranged between 12.6 and 17.0 °C, the soil temperature at the sowing depth remained 14 °C at 5 cm depth and the relative humidity was 66 %.
Heading
It was the initiation of reproductive stage of wheat crop. Heading stage started on 25-02-2013 and was completed on 9-03-2013. The mean air temperature range was between 15 and 23 °C during the heading phase. The relative humidity was around 57 %.
Flowering
Flowering phase of wheat started on 11-03-2013 and completed on 23-03-2013. The mean air temperature range was recorded as 18.8 -24.3 °C and relative humidity around 55 %.
Milk Maturity
Wheat has varying requirements for temperature and soil moisture during seed formation hence effects of meteorological factors have been examined separately. This phase started on 25-03-2013 and ended on 6-04-2013. The mean air temperature was recorded as 20.3 to 25.1 °C whereas mean relative humidity during this phase was 47 %.
Wax Maturity
This phase started started on 8-04-2013 and completed on 17-04-2013. The mean air temperature range between 24.8 to 28.9 °C and relative humidity was recorded as 39 % during wax maturity phase.
Full Maturity
Wheat requires high temperature at this stage for maturity. The mean air temperature range
during phase was recorded as 27.5 to 30.3 °C and the relative humidity was 36 %.
Results and Discussion
The crop variety FSD-2008 is one of the most cultivated varieties of wheat in Punjab including
Faisalabad. The variety has been cultivated for second time (2011-12 and 2012-13) so far in the
experimental field of Ayub Agriculture Research Institute Faisalabad. The Rabi sowing starts in
Pakistan from mid of October and remains up to the end of November. It is recommended that
sowing of wheat should be completed from October, 20 to November,15 in the irrigated areas of
Pakistan. But the crop under discussion was sown on 20-11-2012, which indicates that it was
cultivated late by a week from the recommended period. The time of sowing of wheat is directly
related to with the yield and quality of grain produced.
.
Conclusions
Though Faisalabad is lying in the grain belt of Punjab, but even then far below than standard yield was obtained. This less yield of wheat may partly be attributed to the unfavorable weather conditions and partly to the late sowing of the crop than the recommended period. Moreover, more rain in the month of February and April causes the disease in wheat crop. This unfavorable weather conditions may be responsible for below than normal yield of wheat crop.