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Effect of Green Manure, Sesbania bispinosa Wight Amendment on Incidence of Sucking Insect Pests, their Predators and Yield in Organic Cotton.

Byline: Jam Ghulam Mustafa Sahito, Tajwar Sultana Syed, Ghulam Hussain Abro and Inayatullah Rajpar

Abstract: Cotton holds the key importance in the economy of Pakistan, but its yield is severely affected due to the infestation of many insect pests. Farmers mostly rely on chemicals to control pests but their adverse effects on human health and their interests are also considerable. Therefore, this study was conducted over two years to evaluate the influence of amendment of soil with green manure (GM) Dhancha, Sesbania bispinosa Wight on the population of cotton sucking insect pests and their predators. Significant impact of GM was found in lowering the population of sucking pests of cotton i.e., Thrips tabaci (Lind), Bemisia tabaci (Gennadus), Amrasca bigutulla bigutulla (Ishida) and Tetranychus urticae (Koch) during both years. Population of predators i.e., Chrysoperla carnea, Geocoris punctipes and Orius sp. was also higher in dhancha treated plots in comparison to control.

Application of neem oil was found effective in lowering the population of sucking insect pests during 2014; whereas, application of C. carnea cards showed significant impact after the mid cotton season during 2015. Overall growth and yield parameters were better in dhancha amended organic cotton treatment in comparison to control.

Keywords: Cotton, dhancha, green manure, pests, predators, yield.

INTRODUCTION

Cotton, Gossypium hirsutum, is a key to economic growth of Pakistan. Its contributed share in GDP is 1.5% along with 7.1% share in value added agriculture goods. Cropping area under cotton cultivation has increased at 5.5% from 2,805,700 in 2013-14 to 2,961,000 hectares in 2014-15 that produced 13.983 million bales. There was a rise of 9.5% in comparison to 2013-14 yield of 12.769 million bales.

Such high production of cotton has brought a worth of US$ 10.22 billion foreign exchange to Pakistan [1]. Although, cotton production has shown increasing trends during recent years, but per hectare yield is still low as compared to competing countries. Insect pests of cotton are the major constraints to profitable cotton cultivation throughout the world and their impact particularly in developing countries like Pakistan is still aggravated [2]. Although cotton is not a food crop, about 60% of cotton production is seed that is further processed to get edible oil. It is also used to manufacture cattle feed, and enter into human food chain [3]. About 162 species of insects have been reported as pests of cotton that deteriorated the yield either by direct sucking sap from leaves or by damaging bolls and other cotton parts [4].

Farmers mostly rely on chemical control strategies to control insect pests of cotton; however, they still lose 29% of their potential yield [5]. Moreover, chemicals used in cotton against pests have many adverse impacts to human and their interests. It is estimated that annually about 10,000 farmers and field workers are poisoned by pesticides in Pakistan [6]. Indiscriminate use of chemical has severely affected the natural enemy populations in agro ecosystem and the populations of natural enemies of insect pests have declined up to 90% in cotton growing areas of the country [7]. Organic agriculture is defined as a farming system, where the use of synthetic chemical i.e., pesticides and fertilizers is prohibited. Such systems mainly depend the practices of crop rotations, nitrogen fixation through natural resources, biologically active soil, use of recycled farm manure or crop residue, and control of pests by using biological or mechanical controls [8, 9].

Organic farming is more environment friendly than conventional intensive farming that heavily depends on the synthetic pesticides and fertilizers to get higher crop production. Recent researches have suggested that organic farming results in higher carbon storage and less leaching of nutrients available to plants [10] and lower the level of pesticides in water systems [11]. Organic agriculture increases biodiversity [12, 13]. Wyss et al. [14] proposed a model of pest management for organic crop production involving cultural methods that are well-suited with the natural practices of crop rotation and soil and vegetation management to enhance the impact of natural enemies either by inundating or inoculating the release of natural enemies along with using approved insecticides of biological origin and mating disruption [15].

Several studies have found comparatively less number of pests in organically grown crops in comparison to crop grown by using synthetic chemicals [16-18]. Organic farming is practiced in more than 170 countries on more than 43.1 million hectares with market value of 72 billion USD. This represents less than 1% of total agriculture area of these countries [15]. Social benefits of cotton organic farming include decrease in exposure to harmful agrochemicals and increased income security [19]. The Textile Exchange Organic Cotton Farm and Fiber Report [20] said that about 27.2 million metric tons of organic cotton was cultivated on 35.7 hectares in 2012, which equals 0.7 percent of global agricultural area. Organic cotton is grown in many countries worldwide led by India [21].

In conventional cotton, Pakistan ranked fourth [22], but in organic cotton, Pakistan is not listed in first top ten producers that indicates the lack of knowledge about cultivation of organic cotton in Pakistan. In recent years, many growers have shifted their cotton cultivation practices towards more eco-friendly practices, where application of green manures is of key importance. A green manure (GM) is a crop pulverized into soil for nutrient enrichment and modification of soil in the succeeding crops to improve the economic viability and reduce adverse environmental impacts [23]. Significant effect of application of green manures has been reported on growth and yield parameters of cotton in many countries of the world [24-27].

The slow release of nitrogen through decomposition of green manure residues may be better matched with its uptake by the plant according to its requirement that the inorganic nitrogen, resulting in efficient N-uptake and improved crop yield with least leaching of nitrogen [28,29]. Application of GM can also result in the permanent improvement in organic matter of soil and microbial biomass [30-32], further improving nutrient retention and N-uptak e efficiency. Application of green manure may reduce soil erosion [33], reduce nutrient or pesticide losses [34, 35], and can lower the pest population and support higher natural enemy populations [36-39].

Therefore, keeping in view the significance of insect sucking pests to cotton, adverse effects of chemicals, significance of C. carnea against sucking pests and potential of green manures to improve and maintain soil fertility as a source of organic fertilizer for cultivation of cotton , a two year comprehensive study was conducted to evaluate the effect of application of green manure using dhancha (Sesbania bispinosa Wight) and C. carnea cards for pest management and predator populations in cotton and their ultimate impact on cotton growth and yield parameters.

MATERIALS AND METHODS

Study Location and Experimental Design

The study was conducted at Latif Experimental Farm, Sindh Agriculture University Tandojam, and Sindh during cropping seasons 2013-14 and 2014-2015. A Randomized Complete Block Design (RCBD) with four replications was used for the experiment. The experiment comprised of two treatments: green manure and control. The treatment plot size was 40x50 sq. meters and the replication plot size was 10x50 sq. meter. The type of soil used in the study was clay loam with good texture.

Cultivation of Green Manure, Dhancha (Sesbania bispinosa Wight) and Cotton

Dhancha, Sesbania bispinosa Wight was cultivated and cultured as Green Manure (GM) in first week of April. All applicable agronomic practices were applied as per practice. After week five, standing crop was pulverized and mixed in soil. Cotton variety (Sindh-1) was planted on May 15, 2014 and May 8 2015 by dibbling method on furrows in both GM and control treatments plots. The distance between plant to plant and row to row was 22.5 cm and 75cms, respectively. Weeding and inter-culturing in the crop was carried out manually one month after germination of the crop. Subsequent weeding was carried out after a time interval of one or two months depending upon weed growth. First irrigation was given one month after sowing, while, subsequent irrigations were applied at 10-15 days interval depending upon requirement of the crop.

Application of Neem Oil and Chrysoperla carnea Stephens Egg Cards

In GM treatment plots, when pest population increased and reached the economic injury level, Neem, Azadirchita indica A. oil was applied at fortnightly interval to keep pest populations below economic threshold levels during 2014. The neem oil was applied at the rate of one liter per acre. The Surf(r) detergent was added @ 5 grams per spray tank to emulsify the spray solution. During 2015 crop, C. carnea cards were used @ 5 cards acre-1 at fortnightly intervals as an integrated pest management intervention to control the sucking insect pests. Chrysoperla carnea cards were provided by the Nuclear Institute of Agriculture (NIA), Tandojam. The cards were hanged randomly in the middle of cotton plants.

Data Collection

Sucking Insect Pests and their Predators

Observations on the population of pests and predators were initiated forty days after planting of cotton crop and continued till harvest of cotton at weekly intervals. The data were taken from the plants selected at random (tagged) to check the pest population fluctuation of sucking insect pests in the field. The data were taken in the morning at 8. 30 AM. Observations on sucking complex such as thrips Thrips tabaci (Lind), whitefly Bemisia tabaci (Gennadus), jassids Amrasca bigutulla bigutulla (Ishida) were recorded from five plants per treatment, selected randomly. From each plant, data was collected from one leaf from top, two leaves from middle and two leaves from bottom portion (total five leaves / plant). Both immature and adult insects were recorded for all sucking insect pests. The predator population was recorded from five plants selected at random and whole plant was thoroughly observed for presence of natural enemies.

Population of both nymphs and adult predators was recorded.

Yield Parameters

Plant Height

Height of five randomly selected cotton plants was recorded from each replication, resulting in 20 plants treatment-1. The first observation was taken 60 days after sowing and second after 100 days of sowing of cotton crop. The plant height was measured in centimeters.

Crop Maturity and Yield

The opening of cotton bolls was considered as the maturity of crop. First observation was recorded in the 4th week of August and second in the 3rd week of September. The data on total and opened bolls were taken and percent open bolls were calculated. The data were collected from twenty five plants selected at random from each treatment plot. First picking was done when more than 50% bolls of cotton were open. Two pickings were done and yield per treatment was recorded.

Data Analysis

All collected data was analyzed using Two-way Analysis of Variance, whereas means with significant difference were separated using Least Square Difference (LSD). Statistical software SAS 9.4 was used to analyze all the collected data.

RESULTS AND DISCUssION

Population Fluctuation of Sucking Pests

Results on the population fluctuation of different sucking insect pests showed great variation in dhancha treatment during 2014 in comparison to control. Comparatively higher populations of sucking pests were recorded in control as compared to dhancha. Moreover, a sudden rise in the population of T. tabaci was recorded at the middle of the cotton season, which remained high till the harvesting of cotton. Significant effect of application of neem oil spray was recorded on the population of different sucking pests as reduction in population of pests was recorded during 2014. Significantly higher (F=7.82, DF=1, Pless than 0.011) population of T. tabaci was recorded in control as compared to dhancha. Moreover, significantly higher (F=4.51, DF=1, Pless than 0.043) population of B. tabaci was also recorded in control as compared to dhancha treatment (Figure 1).

No significant difference was recorded between dhancha and control with respect to population of A. bigutulla bigutulla (F=0.49, DF = 1, Pless than .4901) and T. urticae (F=0.11, DF=1, Pless than 0.7447). During 2015, except T. tabaci population of remaining pests fluctuated comparatively less and remained low in both dhancha and control treatments. However, population of B. tabaci showed a sharp increase at the flowering time of cotton, remained at higher densities during the middle growth period of cotton and declined at the end of season in both treatments.

Moreover, application of C. carnea cards did not show any affect in reducing the pest population during the initial growth period of cotton as population of all pests especially T. tabaci tended to show an increasing trend. However, significant influence of application of C. carnea cards was observed after the middle growth period of cotton as population of C. carnea started to establish in the field. No significant difference was recorded in the population of T. tabaci (F=1.23, DF=1, Pless than 0.2810), B. tabaci (F=0.23, DF=1, Pless than 0.6341), A. bigutulla bigutulla (F=0.83, DF=1, Pless than 0.3724) and T. urticae (F=0.07, DF=1, Pless than 0.7997) between control and dhancha treatments (Figure 2). Population of T. tabaci was comparatively higher than other pests; therefore, application of neem oil was made to reduce pest population. Application of neem oil was effective in reducing thrips but it needed repetitive applications because of pest population resurgence.

Population development of B. tabaci, A. b. bigutella and T. urticae was comparatively less severe in dhancha amended cotton than control mainly due to the repeated application of neem oil. Swezey et al. [40] compared pest population between organic and conventionally grown cotton, found Lygus bugs significantly more abundant in the organic than in the conventional fields. Thrips tabaci and T. urticae abundance were not statistically different between the organic and conventional treatments in any of the three years. Jackson [41] conducted experiments on effect of organic and conventional methods of cotton cultivation on pests and predator population and observed comparatively higher populations of T. tabaci in organic treated plots as compared to conventional cotton. Studies by [42, 43] have also reported that populations of A. gossypii, B. tabaci and A. b. biguttula started appearing on cotton around mid-June and peaked in August.

As such, these findings support findings of our study as populations of all above mentioned sucking insect pests have been recorded with T. tabaci being a dominant species.

Population Fluctuation of Predators

Results on the population of predators, showed a great variation in both dhancha and control during 2014 and 2015. Comparatively, higher populations were recorded in dhancha in comparison to control (Figures 4 and 5). Among natural enemies, only significant difference was recorded in the population of C. carnea (F=3.17, DF=1, Pless than 0.0048) during 2015 where higher population of the predator was recorded in dhancha as compared to control treatment. Population of big-eyed bug, Geocoris punctipes (Say) (F=0.41, DF=1, Pless than 0.6731 and F=1.80, DF=1, Pless than 0.3660) and pirate bug, Orius sp. (F=1.20, DF=1, Pless than 0.2442 and F=0.47, DF=1, Pless than 0.6433, respectively) showed no significant difference between dhancha and control treatments in both 2014 and 2015, respectively.

Population of coccinellid predators was recorded only during 2015 with no significant difference (F=0.57, DF=1, Pless than 0.450.2) recorded in the population between dhancha (0.270.12 per plant) and control (0.250.10 per plant). Population of natural enemies remained comparatively high in green manure amended treatment compared with control treatment. Population of C. carnea was higher during 2015 because this predator was released in cotton crop for population management of sucking pests. Swezey et al. [40] while comparing the population of predators in organic and conventional cotton, found population of predatory Lygus bugs significantly abundant in organic cotton. Jackson [41] reported higher populations of Orius spp., L. lineolaris and Lady beetles on organic cotton as compared to conventional cotton treatments.

Study by [44] also reported higher populations of G. punctipes (Say), Omus insidiosus (Say) and various species of spiders in organically managed cotton compared with conventional cotton. Many previous studies have shown positive impacts of organic farming on the population of natural enemies because of no use of pesticides, better habitat for beneficial organisms due to crop rotation, greater crop diversity, and conservation of natural enemies [45-48]. Fertilizer type and concentration and herbivore feeding damage may also interact to affect foliar concentrations of phytochemical and affect insect-plant interactions [49,50].

Plant Growth and Yield Parameters

Plant Height

There was no significant (F=0.11, DF=1, Pless than 0.7450) effect of green manure (dhancha) on plant height during 2014, at 60 days after sowing. However, during 2015, significantly higher (F=51.84, DF=1, Pless than 0.001) plant height was recorded at 60 days after sowing in dhancha treatment as compared to control. Moreover, significant effect of dhancha was recorded on plant height at 100 days after sowing as compared to control during 2014 (F=67.57, DF=1, Pless than 0.001) and 2015 (F=160.28, DF=1, Pless than 0.001) (Figure 5).

Total No of Bolls

Data on number of bolls recorded in dhancha and control treatments are given in Figure 6. According to results, during both years, after 100 days (F=133.63, DF=1, Pless than 0.001 and F=334.16, DF=1, Pless than 0.001, respectively) and 150 days (F=61.46, DF=1, Pless than 0.001 and F=177.69, DF=1, Pless than 0.001, respectively) of sowing, significantly higher number of bolls was recorded in dhancha treatment in comparison to control treatment.

Maturity Percentage

Results of the maturity percentage of bolls indicated that during 2014, after 100 days of sowing, significantly (F=6.30, DF=1, Pless than 0.0365) higher maturity percentage was recorded in control as compared to dhancha treatment. No significant difference (F=0.0441, DF=1, P=0.8363) was recorded between both treatments during 2015 after 100 days of sowing. However, in comparison to control, dhancha treatment showed higher (P less than 0.05) maturity percentage during both 2014 (F=5.41, DF=1, Pless than 0.0467) and 2015 (F=41.73, DF=1, Pless than 0.0002) after 150 days of sowing (Figure 7).

Boll Weight

Results of the boll weight showed that significantly (F=15.13, DF=1, Pless than 0.0081) higher boll weight was recorded in dhancha treatment during 2014; whereas, there was no significant difference (F=0.85, DF=1, Pless than 0.3931) in boll weight during 2015 (Figure 8).

Yield

There was a significant effect of dhancha on the yield of cotton as during both years, significantly higher (F=6.35, DF=1, Pless than 0.0342 and F=141.37, DF=1, Pless than 0.001, respectively) yield was obtained from dhancha treatment as compared to control cotton treatment (Figure 9). In the present study, application of green manure (dhancha) exhibited substantial and significant effects on various growth parameters (plant height, number of bolls, maturity %, boll weight and yield) of cotton. The difference in plant height at 60 days after sowing was not significant but as the nutrients from amendment of green manure were made available, plant growth accelerated and became significantly higher than control. Similarly, other important yield parameters such as number of bolls and boll weight were also significantly higher and heavier than control.

It shows the positive effect of green manure on yield of cotton. [24, 40] have also reported the significant effect of the of green manure on growth and yield traits of organically grown cotton as compared to traditionally cultivated cotton because of low pest incidence and more number of bolls per plan. Similar results have also been reported by [51-53], where comparatively higher yields were recorded in organic cotton treatments.

Bauer et al. [30] Observed significant impact of the application different green manures on yield and lint quality parameters of cotton as green manures provided readily available Nitrogen to cotton as compared to Urea. Eyhorn et al. [54] reported 30-40% higher gross margins from organic than conventional cotton production system However, [55] recorded similar pattern of yield and lint quality parameters of cotton with the application of organic and traditional methods. Accordingly, all above mentioned results supported the findings our study as comparatively higher yield was recorded in green manure applied treatment as compared to control.

CONCLUSION

In the present study of two years, in comparison to control plots, comparatively minimum population of sucking pests was recorded in treatment plots applied with green manure (Dhancha). Moreover, application of green manure also attract more population of predators as comparatively higher populations of C. carnea, Orius spp., G. punctatis and coccinellid predators were recorded in green manure treatment. Significant effect of application of neem oil during 2014 and fixing of C. carnea during 2015 was observed in the reduction of sucking pest population. Application of dhancha also showed improvement in the growth, yield quality parameters of cotton.

ACKNOWLEDGEMENT

Authors are thankful to the Pakistan Science Foundation, Islamabad, Pakistan for award of research grant, project No. PSF/NSLP/S-SAU (242) granted to GHA.

REFERENCES

[1] GOP. Pakistan Economic Survey 2014-15, Government of Pakistan 2016.

[2] Fitt GP. An Australian approach to IPM in cotton: integrating new technologies to minimise insecticide dependence. Crop Prot 2000; 19: 793e800.

[3] Eyhorn F, Ratter SG, Ramakrishnan M. Organic cotton crop guide. A manual for practionners in the tropics 2005.

[4] Sattar M, Abro GH. Mass rearing of Chrysoperla carnea (Stephens)(Neuroptera: Chrysopidae) adults for integrated pest management programmes. Pak J Zool 2001; 43: 483-7

[5] Khan M, Damalas CA. Farmers' knowledge about common pests and pesticide safety in conventional cotton production in Pakistan. Crop Protection 2015; 77: 45-51. http://dx.doi.org/10.1016/j.cropro.2015.07.014

[6] Ahmed I, Soomro MH. Policy Strategy on Rational Use of Pesticides in Pakistan. Undp / Fao Project 2000.

[7] Abbuldahaab A, Hassanin MA. Analytical study of yield and its components of Egyptian cotton under different N levels and plant populations densities. Bulletin of Faculty of Agri Uni Cairo 1999; 42: 1029-41.

[8] Swedish Control Association of Ecological Farming 2003 (Krav-Regler, Uppsala, Sweden).

[9] SoilAssociation 2003; Homepage http://www.soilassociation. org/web/sa/saweb.nsf/Living/whatisorganic.html

[10] Drinkwater LF, Letoumeau DK, Worknoh F, Van Bruggen AHC, Shennan C. Fundamental differences between conventional and organic tomato agro ecosystems in California Ecol Appl 1995; 5: 1098-112.

[11] Mader PM, Pfiffner L, Fliessbank A, Von Lutzow M, Munch JC. Soil Ecology-The Impact of Organic and Conventional Agriculture on Soil Biota and Its Significance for Soil Fertility. In: T.V.Ostergaaard (Ed.) Fundamentals of Organic Agriculture, Proc. 11th Ifoam Scientific Conf. Copenhagen 1996; 1: 24-46.

[12] Paoletti MG, Pimentel D, Stinner BR, Stinner D. Agro ecosystems biodiversity: matching production and conservation biology. Agric Ecosyst Environ 1992; 40: 3-23. http://dx.doi.org/10.1016/0167-8809(92)90080-U

[13] Ahnstron J. Organic Farming and Biodiversity: A Literature Review. Centre for Sustainable Agriculture 2002.

[14] Wyss E, Luka H, Priffner L, Sthlatter C, Uehlinger G, Daniel C. Approaches to Pest Management in Organic Agriculture: A Case Study in European Apple Orchards. Organic Research 2005; pp. 33-36.

[15] Zehnder G, Gurr gm, Kuhne S Wade MR, Wratten SD, Wyss E. Arthropod Pest Management In Organic Crops. Annu Rev Entomol 2007; 52: 57-80. http://dx.doi.org/10.1146/annurev.ento.52.110405.091337

[16] Eigenbrode S, Pimentel D. Effects on Manure and Chemical Fertilizers on Insect Pest Populations on Collards. Agric Ecosyst Environ 1988; 20: 120-5. http://dx.doi.org/10.1016/0167-8809(88)90151-X

[17] Kajimura TY, Maeoka IN, Widcarta T, Sudo K, Hidaka F, Naka S. Effect Of Organic Farming Of Rice Plants on Population Density Of Leaf Hoppers and Plant Hoppers Population Density And Reproduction Rate. Japan J Appl Entomol Zool 1993; 37: 137-44. http://dx.doi.org/10.1303/jjaez.37.137

[18] Aranon NQ, Galvis P, Edwards C. Suppression of insect pest populations and damage to plants By Vermicomposts. Biores Technol 2004; 96: 1137-42. http://dx.doi.org/10.1016/j.biortech.2004.10.004

[19] Franz J, Bobojonov I, Egomberdiev O. Assessing the economic viability of organic cotton production in Uzbekistan: A First Look. J Sustain Agri 2010; 34: 99-119. http://dx.doi.org/10.1080/10440040903396821

[20] Organic Exchange Farm and Fibre Report. Organic Exchange: La Rhea Pepper, 2008. www.TextileExchange. org/FarmHub

[21] Soil Association. Cool Cotton: organic cotton and climate change 2015. Page http://www.soilassociation.org

[22] Anonymous. Country Report Presented by Pakistan Delegation at the 70th Plenary Meeting of International Cotton Advisory Committee held at Buenos Aires, Argentina 4-10th September 2011.

[23] Cherr CM, Scholberg JMS, McSorley R. Green manure approaches to crop production. Agronomy Journal 2006; 98: 302-19. http://dx.doi.org/10.2134/agronj2005.0035

[24] Blaise D. Tillage and green manure effects on BT transgenic cotton (Gossypium hirsutum L.) hybrid grown on rainfed Vertisols of central India. Soil and Tillage Research 2011; 114(2): 86-96. http://dx.doi.org/10.1016/j.still.2011.04.008

[25] Erdogan O, Gore M, Ozbek N. Effects of green manure applications in the control of wilt disease (Verticillium dahliae Kleb.) and yield on organic cotton production. Bitki Koruma Bulteni 2012; 52: 81-91.

[26] Channagouda R, Babalad H, Ajjappalavara P. Effect of organic manures, green manures and liquid organic manure on yield, economics, energy use efficiency and energy pro- ductivity in cotton. Int Journal Trop Agric 2014; 32: 427-32.

[27] Channagouda R, Babalad H, Dineshkumar S. Effect of organic manures, green leaf manures, liquid organic manures and micronutrients on yield and economics of cotton (Gossypium spp.). Indian J Agric Sci 2015; 85.

[28] Aulakh MS, Khera TS, Doran JW. Yields and nitrogen dynamics in a rice-wheat system using green manure and inorganic fertilizer 2000.

[29] Cline GR, Silvernail AF. Effects of cover crops, nitrogen, and tillage on sweet corn. Hort Technol 2002; 12: 118-25.

[30] Bauer PJ, Camberato JJ, Roach SH. Cotton yield and fiber quality response to green manures and nitrogen. Agronomy Journal 1993; 85: 1019-23. http://dx.doi.org/10.2134/agronj1993.0002196200850005000 12x

[31] Chander K, Goyal S, Nandal DP, Kapoor KK. Soil organic matter, microbial biomass and enzyme activities in a tropical agroforestry system. Biol Fertility Soils 1998; 27: 168-72. http://dx.doi.org/10.1007/s003740050416

[32] Campbell CA, Biederbeck VO, McConkey BG, Curtin D, Zentner RP. Soil quality-effect of tillage and fallow frequency. Soil organic matter quality as influenced by tillage and fallow frequency in a silt loam in southwestern Saskatchewan. Soil Biol Biochem 1998; 31: 1-7. http://dx.doi.org/10.1016/S0038-0717(97)00212-5

[33] Dapaah HK, Vyn TJ. Nitrogen fertilization and cover crop effects on soil structural stability and corn performance. Communications in Soil Science and Plant Analysis 1998; 29: 2557-69. http://dx.doi.org/10.1080/00103629809370134

[34] Dabney SM, Delgado JA, Reeves DW. Using winter cover crops to improve soil and water quality. Communications in Soil Science and Plant Analysis 2001; 32: 1221-50. http://dx.doi.org/10.1081/Css-100104110

[35] Gaston KJ. The structure and dynamics of geographic ranges. Oxford University Press 2003.

[36] Mote UN, Patil MB, Tambe AB. Role of intercropping in population dynamics of major pests of cotton ecosystem. Ann Plant Prot Sci 2001; 9: 32-6.

[37] Saminathan VR, Mahadevan NR, Muthukrjshnan N. Crop diversity approach to manage cotton leafhopper Amrasca devsatans. Indian J Entomo 2002; 64: 351-7.

[38] Hegde M, Kulkarni KA, Lingappa S. Impact of intercrops on conservation of Chrysoperla carnea (Stephens) and other natural enemies in cotton ecosystem. Indian J Plant Protect 2003; 31: 98-104.

[39] Kavitha G, Ram P, Saini RK. Impact of Strip Crops on the Population of Arthropod Predators and Insect-pests in Cotton. J Biol Cont 2003; 17: 17-21.

[40] Swezey SL, Goldman P, Jergens R, Vargas R. Preliminary Studies Show Yield and Quality Potential of Organic Cotton. California Agric 1999; 53: 9-16. http://dx.doi.org/10.3733/ca.v053n04p9

[41] Jackson LD. Beneficial and Pest Insect Populations in Conventional and Organic Cotton, and Organic Cotton with Habitat. In: The 2005 ESA Annual Meeting and Exhibition, Chicago, USA 2006.

[42] Abro GH, Syed TS, Tunio GM, Khuhro MA. Performance of transgenic BT cotton against insect pest infestation. J Biotech 2004; 3: 75-81. http://dx.doi.org/10.3923/biotech.2004.75.81

[43] Hanumantharaya L, Goud KB, Naik LK. Use of green lacewing, chrysoperlacarnea (Stephens) and Neem seed kernel extract for management of insect pests on cotton. Karnataka J Agric Sci 2008; 21: 41-4.

[44] Tillman, G, Lamb M, Mullinix Jr B. Pest insects and natural enemies in transitional organic cotton in Georgia. J Entomol Sci 2009; 44(1): 11.

[45] Van Elzakker B, Caldas T. Chapter 3. Organic cotton production. pp. 21-34. In: Organic cotton: from field to final product [eds. Myers, D., and S. Stolton. Intermediate Technology, London 1999; p. 267.

[46] Berry NA, Wratten SD, McErlich A, Frampton C. Abundance and diversity of beneficial arthropods in conventional and "organic" carrot crops in New Zealand. New Zealand J Crop Hort Sci 1996; 24: 307-313. http://dx.doi.org/10.1080/01140671.1996.9513967

[47] Bengtsson J, Ahnstrom J, Weibull A. The effects of organic agriculture on biodiversity and abundance: a meta-analysis. J Appl Ecol 2005; 42: 261-269. http://dx.doi.org/10.1111/j.1365-2664.2005.01005.x

[48] Letourneau DK, Goldstein B. Pest damage and arthropod community structure in organic vs. conventional tomato production in California. J Appl Ecol 2001; 38: 557-570. http://dx.doi.org/10.1046/j.1365-2664.2001.00611.x

[49] Letourneau DK, Goldstein B. Pest damage and arthropod community structure in organic vs. conventional tomato production in California. J Appl Ecol 2001; 38: 557-570.

[50] Gomiero T, Pimentel D, Paoletti MG. Environmental impact of different agricultural management practices: conventional vs. organic agriculture. Critical Reviews in Plant Sci 2011; 30(1-2): 95-124.

[51] Mygdakos E, Patsiali S, Mygdakos G. Economics of Organic Growing Cotton versus Conventional Cotton under Greek Conditions. J Food Agric Environ 2007; 5(/4): 231-236.

[52] Lakha SY, Sidibe H, H'mida S. Comparing Conventional and Certified Organic Cotton Supply Chains: The Case of Mali. Int J Agri Res Governance Ecol 2008; 7(3): 243-255.

[53] Satpute TG, More ss, Sanap DJ. Costs, Returns and Resource Use Efficiency. In: Organic And Inorganic Cotton Farming in Parbhani District. Agriculture Update 2009; 4(1/2): 138-142.

[54] Eyhorn F, Ramakrishnan M, Mader P. The viability of cotton- based organic farming systems in India. Int J Agric Sustainability 2007; 5(1): 25-38.

[55] Bilalis D, Patsiali S, Karkanis A, Konstantas A, Makris M, Efthimiadou A. Effects of cultural system (organic and conventional) on growth and fiber quality of two cotton (Gossypium hirsutum L.) varieties. Renewable Agriculture and Food Systems 2010; 25(03): 228-235. http://dx.doi.org/10.1017/S1742170510000190
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Author:Sahito, Jam Ghulam Mustafa; Syed, Tajwar Sultana; Abro, Ghulam Hussain; Rajpar, Inayatullah
Publication:Journal of Basic & Applied Sciences
Article Type:Report
Geographic Code:9PAKI
Date:Dec 31, 2016
Words:5414
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