Effects Of Plant Growth Regulators On Physiology Property And Quality Of Upper Leaves Of Flue-cured Tabacco In Bijie

Abstract:Field experiments were conducted in Bijie tobacco region of Heba country, Heishitou town, Weining county, Bijie city, Guizhou province in2012. Effect of Plant Growth Regulators on growth, physiological characteristics, appearance quality, internal quality and economic characters was studied, aiming to provide theoretical reference for producing high-quality flue-cured tobacco in Bijie tobacco-growing area.The main results as follows:1. Research showed that three kinds of agent all promote the leaf expansion. Gibberellin-based B1effects A1and A2, so that the upper leaves width compare with the comparison, increasing by12.07%,16.40%respectively, and leaf area increased by34.79%,35.67%. Besides, B3showed good effect on A2. Leaf width increased by9.39%and leaf area increased by16.33%. B2showed the worst effect among the three, but also better than the comparison. Upper leaves of mature period and bottom area index data synchronization showed difference among the treatments.2. Each period, chlorophyll SPAD value of A1comparison was significantly higher than that of A2comparison. Three kinds of agent all improved chlorophyll SPAD value of flourishing interim and budding stage in different degrees.3. Three kinds of agent all improved net photosynthetic rate of A1illumination, and the order of increasing amplitude is as follows:B1>B3> B2. Light saturation points of A1B1, A1B2, A1B3were higher than that of the comparisons, and value of A1B1was the biggest,1557μmol·m-2·s-1, which was very different with other treatments. In A2, only B1improved net photosynthetic rate and light saturation point of each illumination, but three kinds of agent all reduced their light compensation points, from low to high in turn:A2B1, A2B2, A2B3, A1CK. From other photosynthetic response curves, we can see that both B1and B3improve stomatal conductance of A1and A2, reduce their stomatal limitation, but the two kinds of agent increase transpiration rate of A1, while B2shows advantage in reducing transpiration rate of the two and improving their water use efficiency.4. After spraying conditioning agent the first time, A1B1and A2B1improved the content of IAA significantly, and A1B1, A2B3increased GA/ABA, ZR/ABA, IAA/ABA significantly. After spraying the second time, A1B2and A2B2, which were affected by B2, improved the content of ZR and IAA significantly, and A1B1, A2B2can improve GA/ABA, ZR/ABA, IAA/ABA significantly, but A2B1reduced the GA/ABA, ZR/ABA significantly.5. From mature organizational structure, we can see that A1B1, A1B3reduced the palisade tissue and leaf thickness significantly, A1B1also significantly reduced the density of palisade cells. In A2, three kinds of agent reduced the palisade tissue significantly, but other indicators had no significant difference compared to the comparison.6. Three kinds of agent all increased leaf width and leaf weight, the widened effect is:B1> B3> B1. The cured-tobacco leaves of A1and A2, after spraying B1, showed that the oil becomes less, the chromaticity becomes weaker, the structure becomes loose, and identity becoming thin. B2makes A1structure become dense, while B3made the upper leaf thinning of the identity and perform stably relatively.7. The results showed that the three preparations have contributed to the improvement of economic efficiency of tobacco, of which the most prominent effect of B1, A1B1and A2B1compared with the control, respectively, an increase of2407.11yuan,2407.11yuan, the upper leaf superior tobacco to increase the proportion of18.25%、16.67%.Followed by B3, A1B3and A2B3mu value compared with the control, respectively, an increase of1595.16yuan,1699.41yuan, the upper leaf superior tobacco to increase the proportion of, respectively,14.10%,10.50%, the lowest value-added B2, A1B2and A2B2mu value than the control were increased by994.56yuan,1699.41yuan, upper leaves superior tobacco to increase the proportion of6.33%and11.17%.8. The effect of B1on two varieties was "reducing sugar, reducing alkali, increasing potassium, increasing chlorine". The reducing sugar and total sugar of A1B1were lower than the comparison A1CK23.57%,31.14%by19.51%,24.22%. That of A2B1were lower than the comparison A2CK24.96%,31.56%by22.72%,30.52%. Their reduction amplitudes of nicotine are9.94%,14.13%and potassium content increased by18.75%,5.33%respectively. The chlorine ion values increased by0.14and0.03. The interaction rules of remaining two kinds of agent in two varieties are not consistent.9. Three kinds of agent all played a lifting effect on phenylalanine, chromoplast alkanes, brown product aroma substances of roasted middle leaves. From all kinds of aroma components content of roasted upper leave, we can see only B1has same effect on A1, A2and increases phenylalanine Aroma content.10. The evaluation results showed that spraying B3in two varieties significantly improves the sensory quality of middle and upper leaves. It showed good performance on aroma quality, aroma content and aftertaste. Sensory quality of tobacco leaves sprayed by Bl decreases obviously compared with the comparison, very different from other treatments, particularly in impurity gases. On the whole, spraying naphthalene acetic acid-based B3in this tobacco-growing area can improve net photosynthetic rate and light saturation point of A1, and it also can improve leaf area index of A1and A2, increasing leaf width, reducing the blade thickness and nicotine content of roasted leaf. Besides, both economic trait and tobacco sensory quality of middle, upper leaves were better than other treatments. So, further demonstration study is valuable in this tobacco-growing area.