Transcript Evaluation of adaptability and yielding ability of bt

Evaluation of Adaptability and Yielding
Ability of BT Cotton Varieties under Arid
Region of Bahawalpur.
Introduction
Cotton:
 Cotton being a non‐food cash crop contributes significantly in
foreign exchange earning. Cotton accounts for 8.6 percent of
the value added in agriculture and about 1.8 percent to GDP.
 In the year 2009-10 total production was 12698 thousands
bales. Crop was sown on the area of 3106 thousand hectares
(GOP,2010).
Conti…..
Bt Cotton
 Bt cotton is developed by Genetic Engineering techniques
(Biotechnology). Bt cotton contains Genes from bacteria
Bacillus thuringiensis (Bt.)
 Eight countries commercially grew Bt cotton (USA, Australia,
China, India etc.). Protein of this gene is deadly for the Chewing
Pests.
 There may be 30% increase in cotton yield due to resistance
against chewing pest and hence additional income to poor
farmers.
Conti…..
 The Bt. cotton varieties including Bt hybrids currently grown
in Pakistan are from exotic sources which are given to farmers
for cultivation without validating these performance and
without providing production technologies based on research
conducted according to local environment.
(Economic survey of Pakistan 2009-2010)
 All the Bt. cotton varieties grown are susceptible to Cotton
Leaf Curl Virus (CLCV) and sucking pest i.e. mealy bug,
Jassid and White fly which are a major threat to cotton crop.
Review of Literature
 Among the comparative growth and yield performance of four
cotton varieties, Bt-121 had maximum value for seed cotton
weight per boll and maturity percentage and produced 26%
higher seed cotton yield than all other cultivars (Aziz et al).
 Seed cotton is mainly a function of boll number per plant. The
significant difference in boll number per plant among different
cotton cultivars observed might be due to inherent capacity.
and inability of some genotypes to provide photosynthates to
large number of bolls (Nisar et al., 2007 and Tahira at et al
2007).
Conti…..
 Maximum seed cotton yield was produced when cotton was
sown from 15th April to 1st May in Nawabshah (Arain et
al.,2002).
 The yield decreased significantly in mid and end June sowing
dates (Muhammad et al.,2002) .
 Cotton yield is affected by different sowing dates under the
various climatic condition (Ali et al.,2004) .
Conti…..
 Short season cultivars produced more dry matter than long
season cultivars due to greater radiation use efficiency and
light interception. It is only due to earlier canopy development
(Bang and Milory.,2000).
 Early sowing (20thMay) produced 10% more flowers,23%
more open bolls, 18% more seed cotton yield and 13% more
ginning out turn (GOT) than the late sowing (10th June)
(Arshad.,2005).
Objectives
 To study the impact of sowing time on phenology and growth
of Bt cotton cultivars.
 To study the yield performance of Bt cotton sown at various
sowing dates.
Materials and Methods
 The experiment was conducted in 2011 at Regional Agriculture
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Research Institute, Bahawalpur.
Design: RCBD with split plot arrangement.
plot size: 3m ×7m
R×R: 75cm
P×P: 22cm
Seed rate: 25kg ha-1
Other cultural practices were kept normal .
Materials and Methods
Treatments:
Factor A: Sowing dates
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SD1=15 February
SD2=15March
SD3=15April
SD4=15May
SD5=15June
Factor B: BT Varieties
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V1=886
V2=121
V3=3701
V4=703
Crop growth data
 Leaf Area Index
LAI= Leaf area / Land area
 Crop Growth Rate
CGR=W2-W1 / T2-T1
 Leaf Area Duration
LAD=(LAI1+LAI2)×(T2-T1)/2
 Net Assimilation Rate
NAR=TDM / LAD
Yield and yield component
 No. of plants per plot.
 Plant height(cm).
 Total number of bolls per plant.
 Number of un opened boll per plant.
 Number of opened boll per plant.
 Average boll weight.
 Seed cotton yield Kg per hactere.
 Ginning out turn.
 Harvest index.
Number of plants m-2 at harvest
 Total number of plants in each plot was counted and it was
divided to total plot area to get plants m-2.
Plant height(cm)
 Plant height was determined
at maturity with the help of
a meter rod. The heights of
three randomly selected
plants plot-1 was measured
from soil surface to the tip of
the plant and then averaged.
No. of monopodial branches plant-1
 Number of monopodial
branches plant-1 were
counted from 5 randomly
selected plants from each
plot and then averaged in
each treatment.
Number of sympodial branches plant-1
 Number of sympodial branches per plant were also counted
from 5 randomly selected plants from each plot and average
number of sympodial branches was calculated.
Number of boll plant-1
 For number of bolls per
plant,5 plants were selected
randomly from each plot and
then averaged.
Number of un-opened boll plant-1
 For un-opened bolls, 5 selected plants were examined and un-
opened bolls were calculated and then averaged.
Number of opened bolls plant-1
 The selected 5 plants were picked separately, counted the
number of opened bolls plant-1 ,and then the average was
calculated.
Average boll weight(g)
 Average boll weight was obtained by dividing the total yield of
seed cotton per plant by the total number of bolls picked from
that particular plant. Then the average boll weight plant -1 was
computed for each plot.
100-cotton-seed weight(g)
 100-cotton seed were selected randomly from each plot and
weighed.
Seed cotton yield(kg ha-1)
 Crop was picked three times
at present. Seed cotton
weight plot -1 was weighed in
addition.
References
 Ahsan, A., N. Akhtar, M. Afzal, M. Ashraf, A. Tanveer, R. Ahmad
and M. Ehsan. 2011. Comparative performance of Bt cotton with
some elite conventional cotton cultivars under arid to semi-arid
Conditions. African J. of Agricultural Research. 5(6): 1600-1606.
 Ali. M., Ghulam mohy-ud-din, M. Anjam ali, S. Bashir and L. ali
2004. Response of cotton genotypes to time of sowing. Asian J. of
Plant. Sci., 1 (5): 538-539.
 Arain, M.H., M.J.Baloach, C.K. Kalwar, and A.A. Memon. 2002.
performance of new developed cotton strains under different
sowing dates. Pak. J.Bio. Sci., supplementary Issue No. 1.
 Arshad, M. 2006. Modeling the growth, development and
radiation use efficiency of four cotton, cultivars with two sowing
dates under the climatic conditions of Faisalabad. Msc. thesis
Dept. of Agron. Univ. of Agri. Faisalabad.
 Bang, M.P., and S.P. Milory. 2000. Timing of crop maturity in
cotton. Impact of dry matter production and partioning. CSIRO.
Plant Industery, Australian Cotton cooperation Reseach center,
Fid. Crop Res., 68(1): 143-155.
 Economic Survey of Pakistan. 2009-10. Ministry of Finance,
Government of Pakistan.