Effect of Topping Height and Timing on Quantity and Quality Influe-Cured Tobacco (Var.K326)

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Avilble online t http://www.ijbbr.com Interntionl journl of Advnced Biologicl nd Biomedicl Reserch Volume 2, Issue 4, 2014: 1388-1395 Effect of Topping Height nd Timing on Quntity nd Qulity Influe-Cured Tobcco (Vr.K326) Rmine Mesbh*, Rez Mohsenzdeh nd Mohmmd Rez Serji Resrchers of Tirtsh Reserch nd Eduction Center, Behshhr, Mzndrn, Irn Abstrct One of the most importnt prctices in flue-cured tobcco frming is topping nd sucker control t the right time. Topping cuse's development nd root growth, drought tolernce, reduce deployment pests, incresed synthesis of nicotine.this study ws conducted in rndomized complete block design (RCBD) with 10 tretments in 3 replictions over two yers (2008-2009) t Tirtsh reserch nd eduction center. Tretments consisted of three phses(button stge, erly flowering nd full flowering) nd three levels of lef removl (18, 20 nd 22) with the control tretment without topping nd sucker control.the results of combined nlysis showed tht there were significnt differences between tretments for fresh weight, cured lef weight, totl income, net income, men price, sugr nd nicotine percent (α = 1%). According to results the highest nd lowest cured-lef yield belongs to topping t button stge with 22 with 4546 kg/h nd control with 3054 kg/h respectively. Key words: Tobcco, Flue-cured, Topping height, Qulity nd Quntity Introduction To mximize lef production nd encourge lef-ripening, topping (removl of the flowering hed nd young ) is n essentil cultivting mesure for ir-cured tobcco, which switches the plnt from reproductive to vegettive phse (Gooden et l., 2011,Czubck et l., 2012). Topping lwys refers to the removl of the tobcco flower before the re systemticlly removed (Singh et l., 2000, Lin et l, 2004, Wng et l., 2012). Removing the flower switches the plnt from seed producing (reproductive) to lef producing (vegettive) phse (Pndey et l., 2001, Wng et l., 2012). Topping increses the size nd weight of, incresing the overll yield per hectre (Singh et l., 2000, Ho nd cho yng, 2001,Roton et l., 2005, Reed et l., 2012). Topping stimultes root growth, the source of nicotine, which improves drought tolernce. In ddition, topping increses yield through incresed growth, especilly of the upper. Topping stimultes theproduction of secondry plnt products tht ccumulte in the (Yi et l., 2006). These products give the cured lef improved qulity nd smoking chrcteristics (Hu et l., 2000). Topping lowers the popultion of severl insects tht re ttrcted to the plnt by the flowers. Topping is turning point for nicotine formtion nd ccumultion inside tobcco plnt (Hu et l., 2000,Roton et l., 2005). However, before topping the quntity of nicotine formed is reltively smll due to only bout 2.5% of nitrogen bsorbed by tobcco plnt to be used for nicotine formtion. While, fter topping, the proportion of nitrogen bsorbed by tobcco plnt used for Corresponding Author E-mil: mesbh_y@yhoo.com 1388 Pge

nicotine formtion goes up drsticlly, reching 16% or so, resulting in significnt increse of nicotine content in tobcco plnt (Mizuski et l., 1971, Pge et l., 1982,Legget et l., 1977, Wng et l., 2012,Frrokh et l., 2012). Topping stge of tobcco is key time for development of griculturl mesures to promote the qulity of (Hoet l., 2001, Reed et l., 2012). Lte topping increses the number of pretopping suckers tht must be removed s well s the chnce of plnts blowing over in windstorm. Topping height is nother spect of topping mngement. Topping height is mostly mtter of personl preference; there is not one correct topping height. However, burley tobcco should be topped t height resulting in plnts tht re efficiently hndled in the field nd in the brn. Tll plnts re difficult to hndle, requiring extr lbor, nd mke curing more difficult. Ho nd Cho yng (2001) reported tht yield did not continue to increse when plnts were topped t more thn 22 hrvestble. Legget et l (1977) found tht n increse in topping height decresed totl lkloids nd price, but incresed yield nd n increse in plnt spcing tended to increse totl lkloids, but hd little effect on sugrs. Therefore, the objectives of this reserch were to understnd the influence remove of lef number nd topping timing on qulity nd quntity chrcteristics in flue-cured tobcco(vr. K326). Mteril nd Methods The study ws conducted under field conditions t the Tirtsh Reserch nd Eduction Center using completely block rndomized design with three replictions on flue-cured tobcco (vr. K326)over two yers (2008-2009). Tretments wereincluding lef number removl nd topping timing consisting: 1- control, without sucker control nd topping2- Topping t button stge nd removl of 18. 3- Topping t button stge nd removl of 20. 4-Topping t button stge nd removl of 22. 5- Topping t erly flowering nd removl of 18. 6-Topping t erly flowering nd removl of 20. 7- Topping t erly flowering nd removl of 22.8- Topping t full flowering nd removl of 18. 9- Topping t full flowering nd removl of 20. 10-Topping t full flowering nd removl of 22.Plots mesuring 8x5m, with 2m spcing between plots ws demrcted fter disc hrrowing ndridging by trctor. The fertilizers NPK t concentrtions of 300, 100 nd 100 kg h-1 were pplied in the formof mmonium nitrte, dimmonium phosphte nd muritic of potsh, respectively. All of PK nd hlf of N(strter fertilizer) were mixed with the soil t the time of trnsplnting, while remining N ws pplied t erlybutton stge. These fertilizers were pplied over the surfce of the soil nd in order to ssess the uniqueeffect. The seedlings were grown in flot system1 from mid-februry to the beginning of My. Tobccoseedlings were trnsplnting in six-lef nd one-shoot period; then, wter ws poured ppropritely.tobcco plnts spced 50 cm in rows 100 cm. Yield dt were collected fter brn curings the tobcco ws grded. Other fctor s evluted included totl income, net income, men price nd nicotine percent. Dt were subjected to ANOVA using the SAS sttisticl softwre pckgend Duncn's multiple rnge tests were performed to compre the tretment mens. 1389 Pge

Tble 1. Anlysis of vrince of the effect of topping on fresh lef weight, cured lef weight, tobcco price verge, totl income, net income nd nicotine percent in 2008-2009 yers. S. O. V. D. F. Fresh lef Cured lef Tobcco weight weight price verge Totl income Net income Nicotine Block 2 3195174 185080 2401608 112740673 112740673 0.07 Tretment 9 73833797** 21787605** 577027879** 181837020** 2059595989** 4.6** yer 1 529206481** 21787605** 577027879** 743341606** 1935971206** 4.6* AB 9 14938090** 283411** 4054893** 228227751** 232771154** 0.16* Error 36 4558078 81621 698055 53120193 53120193.041 Coefficient of vrition (%) 11.05 10.4 14.58 14.73 11.7 13.44 * nd ** : significnt t 5% nd 1% of probbility levels, respectively. Results nd Discussion Anlysis of vrince of the topping experiment on qulity flue-cured tobcco showed thtdifferences were significnt for chrcters mesured fresh nd cured lef yield, totl income, net income, men price nd nicotine percent. Results in this study shown tht, lef number removl nd topping timing flue-cured tobcco hs significnt influence on fresh nd cured yields (Tble 2). Tble2: Comprison men of fresh lef yield nd cured lef yield of flue-cured tobcco in different tretments (two yers men) tretments fresh lef yield (kg/h) cured lef yield (kg/h) Control 24120 ef 3054 f topping t button stge nd removl of 18 24610 def 3850 d topping t button stge nd removl of 20 27820 bc 4155 bcd topping t button stge nd removl of 22 30530 4645 18 20 22 topping t full flowering nd removl of 18 topping t full flowering nd removl of 20 23870 f 3406 e 27120bcd 3945 cd 29250 b 4398 b 23830 ef 3384 ef 25380 cde 4099 bcd 1390 Pge

topping t full flowering nd removl of 22 28400 b 4233 bc In our experimentl, fresh nd cured lef yields incresed t topping in button nd erly flowering of 22 but t ll topping time of 18 nd control tretment decresed. Low performnce control nd tretments with 18 indicte tht more number of hrvested in control could not ffect the usefulness of topping tretments. The object of topping is to divert the nutrients of the plnt to the insted of flowers nd seeds with the result gining in the size nd body of the lef (Qi et l., 2011). It gives uniform qulity of product nd prevents excessive corseness in the (Zhou et l., 1996; Wng et l, 2012).Lowest tobcco price verge chieves t control tretment nd topping t full flowering nd removl of 18 (figure 1).Topping in the button stge of plnt development is the culturl prctice tht gives tobcco its desired physicl chrcteristics tht led to high texture nd elsticity of lef nd chieves high price verge (Singh et l., 2000). 20000 19000 18000 17000 16000 d bc bc bc b cd bc 15000 14000 13000 1 2 3 4 5 6 7 8 9 10 tretments Figure 1. Effect of topping height nd timing on tobcco price verge (rils/kg). 1: Control (without topping nd sucker control). 2: topping t button stge nd removl of 18. 3: topping t button stge nd removl of 20. 4: topping t button stge nd removl of 22. 5: topping t erly flowering nd removl of 18. 6: 20. 7: topping t erly flowering nd removl of 22. 8: topping t full flowering nd removl of 18. 9: topping t full flowering nd removl of 20. 10: topping t full flowering nd removl of 22. Topping tbutton nd erly flowering stges of22 hs highest totl nd net income in our experimentl (Tble 3). Reserch results indicte tht witing beyond these stges to top results in decresed yields nd incresed lbor requirements for topping, since stlks re tougher nd suckers must be removed. Also, suckers re usully esier to control when tobcco is topped on time. The lbor requirement for mking two to three "on time" toppings is not significntly greter thn for mking one topping when mny plnts re in full flower. Topping height is mostly mtter of personl preference; there is not one correct topping height (Zuo nd Zhun, 1993). 1391 Pge

Tble 3: Comprison men of totl income nd net income of flue-cured tobcco in different tretments (two yers men) tretments Totl income Net income (1000 rils/h) (1000 rils/h) Control 49210 e 49210e topping t button stge nd removl of 18 71840 c 69940 bc topping t button stge nd removl of 20 75880 bc 70220 bc topping t button stge nd removl of 22 87990 81120 18 20 22 topping t full flowering nd removl of 18 topping t full flowering nd removl of 20 topping t full flowering nd removl of 22 59400 d 57500 de 71700 c 66220cd 81910 b 75280 b 58300 d 56330 e 77080 bc 71870 bc 78090bc 72000 bc Height of topping nd topping timing hs been shown to ffect yield, subjective qulity, nd physicl nd chemicl chrcteristics (Brown nd Terrill, 1973; Tso, 1990). Topping in the erly button stge of plnt development is the culturl prctice tht gives tobcco its desired chemicl nd physicl chrcteristics tht led to high yields of high qulity lef (Singh et l., 2000).Lowest tobcco nicotine percentws in control tretment.results in this study shown tht, lef number nd topping timing flue-cured tobcco hs significntinfluence on nicotine formtion (fig. 2).Mny reserch results show tht nicotine increses by topping on right time.the increse in nicotine synthesis fter topping is one of the typiclresponses of flue-cured tobcco to topping(wng et l., 2012; Frrokh et l., 2012). 1392 Pge

2.5 2 1.5 1 c b b b b b b 0.5 0 1 2 3 4 5 6 7 8 9 10 tretments Figure2. Effect of topping height nd timing on nicotine percent. 1: Control (without topping nd sucker control). 2: topping t button stge nd removl of 18. 3: topping t button stge nd removl of 20. 4: topping t button stge nd removl of 22. 5: 18. 6: 20. 7: 22. 8: topping t full flowering nd removl of 18. 9: topping t full flowering nd removl of 20. 10: topping t full flowering nd removl of 22 Conclusion In experimentl indicted tht, topping stge is the essentil for cured lef yield production in flue-cured tobcco. Topping in tobcco is one of the most importnt opertions to improve growth, development nd qulity. In our experimentl, topping t button or erly flowering stges with 22 hs highest yield, net income nd nicotine percent. Control tretment hs the lowest quntity nd qulity chrcteristics. References Brown GW nd Terrill TR.(1973). Effects of method of hrvest on flue-cured tobcco. Prt II. Chemicl components. Agronomy Journl. 65: 268-273. Czubck A, Doroszewsk T, nd Trojk-Goluch A.(2012). Agronomic chrcteristics of trnsgenic tobccodoubled hploids resistnt to Potto virus Y Journl of Food, Agriculture nd Environment. 10 (4):374-378. Frrokh AR, Azizov I, Frrokh A, Esfhni M, Rngbr M, nd Kvoosi R.(2012). The effect of nitrogen Tretments ndpotssium fertilizer on yield nd minerl ccumultion in flue-cured tobcco. Journl of Agriculturl Science. 4: 167-178.Intl. J. Agron. Plnt. Prod. Vol., 4 (8), 2081-2085 Gooden DT, Brown AB, Ellington G, Fortnum BA, Mrshll MW, Rey-Jones F.(2011). South Crolin tobcco growers guide. Pp: 90Guo H, Kn Y, nd Liu W, 2011. Differentil expression of mirnas in response to topping in flue-curedtobcco (Nicotintbcum) roots. Plos one. 6 (12): 1-15. 1393 Pge

Ho J, nd Cho yng C.(2001). Effects of topping nd remined on the yield nd qulity of fluecuredtobcco vriety K326. Journl of Fujin Agriculturl University. 2001-2003. Hu GS, Li ZY, Mu L nd Hn JF.(2000). Studies on chrcteristics of nicotine ccumultion in Nicotin tbcuml. Chin Tobcco Journl. 6(2): 6-9. Leggett JL, Sims JL, Gossett DR, Pl UR nd Benner JF. (1977). Potssium nd mgnesium nutrition effectson yield nd chemicl composition of burley tobcco nd smoke. Journl of Plnt Science. 57:159-166. Lin GH, Zhou JH, Fn QF, Yng HQ nd Co YX.(2004). Effects of topping technology on lef yield, qulitynd lkloid content of flue-cured tobcco. ActBotnicBoreli-OccidentliSinic. 7: 1362-1366. Mizuski S, Tnbe Y, Noguchi M nd Tmki E.(1971). Phytochemicl studies on tobcco lkloids. XIV.The occurrence nd properties of putrescine N-methyltrnsferse in tobcco roots. Plnt Cell Physiology. 12(4):633-640. Pge AL, Miller RH nd Keeney DR.(1982). Methods of Soil the shoot pex increse the nicotine Concentrtion nd nitrogen contents in tobcco plnts. Annls of Botny. 96:793-797. Pndey RS, Ros N, Wite FH, nd Elliot JM.(2001). Rpid estimtion, of some flue-cured tobcco chemiclchrcteristics by infrred reflectnce spectroscopy. Tobcco science. 22:27-31. Qi YC, M L, Wng FF, nd Liu, WQ.(2011). Construction nd nlysis of roots suppression subtrction hybridiztion cdna librry fter tobcco topping. ScientiAgriculturSinic. 44(7): 1331-1337. Reed TD, Johnson CS, Semtner PJ, nd Wilkinson CA.(2012). Flue-cured tobcco production guide. Incoopertion with the Virgini Bright Flue-Cured Tobcco Bord. Pp: 140. Roton C, Wiernik A, Whlberg I, nd Vidl B.(2005). Fctors influencing the formtion of tobccospecificnitrosmines in french ir-cured tobccos in trils nd t the frm level. BeitrgezurbkforschungInterntionl/Contributions to Tobcco Reserch. 21: 305-320. Singh KD, Tripthi SN, nd Pndey AK. (2000). Influence of topping on yield, physicl lef qulity prmetersnd economic return in chewing tobcco. Tobcco Reserch. 1999. P: 61. Wng T, Wng S, Kng X, Tng J, Wei X, Peng W, nd Gun G.(2012). Effect of phosphorus nd potssiumnutrition on nicotine nd nutrient ccumultion during topping stge of NicotintbcumL. Journlof Food, Agriculture nd Environment.10(2): 732-740. Yi JH, Ji ZH nd Sun ZJ.(2006). Effect of the topping time on the root growth nd the content of nicotine offlue-cured tobcco. Journl of Anhui Agriculture Science. 34(12): 2762-2777. 1394 Pge

Zuo TJ nd Zhun ZQ.(1993).Production, Physiology nd Biochemistryof Tobcco. Shnghi Yundong Press, Shnghi. pp. 35-186. 1395 Pge