Uji Formulasi dan Uji Efektivitas Repelan Lotion Ekstrak Daun Tembakau (nicotiana tabacum. L) Terhadap Nyamuk Aedes Aegypti

Tobacco leaves (Nicotiana tabaccum. L) have great potential as a pesticide or insect repellent, especially the Aedes aegypti mosquito. Maceration method was used to obtain tobacco leaf extract as much as 127.86 grams from the dried simplicia of tobacco leaves (Nicotiana tabaccum. L) 827 grams (yield 15.46%). The tobacco extract was made in the form of lotio with a concentration of 1%, 2%, and 3%, having repellant effectiveness of 90%, 96% and 100%, respectively. Physical stability test was carried out on the lotion 0%, 1%, 2%, and 3% as follows; organoleptic test (brownish color, typical tobacco aroma and homogeneity), spreadability test (6.1cm; 6.1cm; 6.2cm; 6.4cm), adhesion test (3.06sec; 2.8sec; 2.75sec; 2.61sec), cycling test (brownish color, thick consistency, homogeneity, and distinctive aroma of tobacco), pH test (7; 7; 7; 6,3), and viscosity test (4.708cPs, 4.575cPs, 4.465cPs, 4.403cPs). The results of One Way ANOVA analysis showed that there was a significant difference in each concentration of tobacco leaf extract lotio and Tukey's test showed that the repellant ability of 3% concentration had 100% percent repelance. It can be concluded that the ethanol extract lotion of tobacco leaves (Nicotiana tabaccum. L) has repellant effectiveness.Keywords: tobacco leaves, extract, lotion, repellant, ANOVA AbstrakDaun tembakau (Nicotiana tabaccum. L) memiliki potensi besar sebagai pestisida atau pengusir serangga khususnya nyamuk Aedes aegypti. Metode maserasi digunakan untuk mendapatkan ekstrak daun tembakau sebanyak 127,86 gram dari simplisia kering daun tembakau (Nicotiana tabaccum. L) 827 gram (rendemen 15,46%). Ekstrak tembakau dibuat dalam bentuk lotio dengan konsentrasi 1%, 2%, dan 3% memiliki efektivitas repelan berturut-turut adalah 90%, 96% dan 100%. Dilakukan uji stabilitas fisik terhadap lotio 0%,1%, 2%, dan 3% sebagai berikut; uji organoleptis (warna kecoklatan, aroma khas tembakau dan homogen), uji daya sebar (6,1cm; 6,1cm; 6,2cm; 6,4cm), uji daya lekat (3,06detik; 2,8detik; 2,75detik; 2,61detik), uji cycling test (warna kecoklatan, konsistensi kental, homogen, dan aroma khas tembakau), uji pH (7;7;7;6,3), dan uji viskositas (4.708cPs, 4.575cPs, 4.465cPs, 4.403cPs). Hasil analisis One Way ANOVA menunjukkan adanya perbedaan yang signifikan pada setiap konsentrasi lotio ekstrak daun tembakau dan uji Tukey menunjukkan kemampuan repelan konsentrasi 3% memiliki persen repelansi 100%. Hal ini dapat disimpulkan bahwa lotio ekstrak etanol daun tembakau (Nicotiana tabaccum. L) memiliki efektivitas repelan.Kata kunci: : daun tembakau; ekstrak; lotion; repelan; ANOVA

Qualitative Discrimination of Intact Tobacco Leaves Based on Near-Infrared Technology

To explore the application of near-infrared (NIR) technology to the quality analysis of raw intact tobacco leaves, a nondestructive discrimination method based on NIR spectroscopy is proposed. A “multiregion + multipoint” NIR spectrum acquisition method is developed, allowing 18 NIR diffuse reflectance spectra to be collected from an intact tobacco leaf. The spectral characteristics and spectral preprocessing methods of intact tobacco leaves are analyzed, and then different spectra (independent or average spectra) and different algorithms (discriminant partial least-squares (DPLS) and Fisher’s discriminant algorithms) are used to construct discriminant models for verifying the feasibility of intact leaf modeling and determining the optimal model conditions. Qualitative discrimination models based on the position, green-variegated (GV), and the grade of intact tobacco leaves are then constructed using the NIR spectra. In the application and verification stage, a multiclassification voting mechanism is used to fuse the results of multiple spectra from a single tobacco leaf to obtain the final discrimination result for that leaf. The results show that the position-GV discrimination model constructed using independent spectra and the DPLS algorithm and the grade discrimination model constructed using independent spectra and Fisher’s algorithm achieve optimal results with intact leaf NIR wavenumbers from 5006–8988 cm−1 and the first-derivative and standard normal variate transformation preprocessing method. Finally, when applied to new tobacco leaves, the position-GV model and the grade model achieve discrimination accuracies of 95.18% and 92.77%, respectively. This demonstrates that the two models have satisfactory qualitative discrimination ability for intact tobacco leaves. This study has established a feasible method for the nondestructive qualitative discrimination of the position, GV, and grade of intact tobacco leaves based on NIR technology.

OPTIMIZATION OF DRYING OF TOBACCO LEAF WITH A SLIT OF THE MIDDLE VEIN ACCORDING TO THE QUALITY INDICATORS OF TOBACCO RAW MATERIALS

При производстве табачного сырья важную роль играет сокращение продолжительности сушки табачных листьев. Одним из способов интенсификации сушки свежеубранных табачных листьев является прием прорезания средней жилки (ПСЖ) листьев вдоль волокон. По результатам исследований 2019–2020 гг. была создана база данных табачного сырья, полученного при естественном способе сушки с применением приема ПСЖ, которая может служить информационным материалом для производителей табака. Проведена оптимизация процесса сушки табачного листа ПСЖ по показателям качества табачного сырья для расширенного диапазона сортотипов табака. Объектом исследований были сорта отечественной селекции, включенные в Государственный реестр селекционных достижений, допущенные к использованию: Самсун 85, Вирджиния 202, Юбилейный новый 142, Трапезонд 92, Трапезонд 204, Дюбек 33, Американ 287 и Крупнолистный Ильский (находится в стадии государственных испытаний). Критерием оценки эффективности применения приема ПСЖ на исследованных сортах табака являлся совокупный сравнительный анализ следующих показателей контрольных (без ПСЖ листа) и опытных образцов: уровень интенсификации сушки, показатели товарного качества, технологических свойств и химического состава полученного сырья. Установлено, что ПСЖ позволяет интенсифицировать процесс сушки в 1,3–2,46 раза в зависимости от сорта табака и положительно влияет на технологические свойства сырья, у большинства сортов увеличивается выход волокна и сохраняются объемно-упругие свойства. Динамика сушки оказывает влияние на изменение химического состава сырья. В процессе сушки за счет гидролизации солей никотина и его освобождения путем окисления кислородом воздуха уровень никотина в ряде образцов снижается в пределах 10–30%. Чем выше содержание никотина, тем выше крепость табака, грубее его вкус. Изменения углеводно-белкового соотношения в сторону повышения углеводов улучшают вкусовые характеристики сырья. По каждому исследованному сорту не удалось выявить закономерной зависимости его структуры и характера процесса сушки при ПСЖ с преобразованиями химического состава сырья. На основе анализа технологических и качественных показателей табачного сырья, представленных в разработанной базе данных по интенсификации сушки различных сортов табака с применением приема ПСЖ табачных листьев, можно планировать выбор оптимального способа сушки для каждого сорта табака, позволяющего повысить эффективность использования сырья и улучшить его качественные характеристики. In the production of tobacco raw materials, reducing the drying time of tobacco leaves plays an important role. One of the ways to intensify the drying of freshly harvested tobacco leaves is the method of cutting the middle vein (CMV) of the leaves along the fibers. Based on the results of research in 2019–2020, a database of tobacco raw materials obtained by a natural drying method using CMV reception was created, which can serve as information material for tobacco producers. The optimization of the process of drying the CMV tobacco leaf according to the quality indicators of tobacco raw materials for an expanded range of tobacco variety types was carried out. The object of research was the varieties of domestic selection included in the State Register of Breeding Achievements, approved for use: Samsun 85, Virginia 202, Yubileyny novy 142, Trapezond 92, Trapezond 204, Dubek 33, American 287 and Krupnolistnyy Ilskiy (under state testing). The criterion for evaluating the effectiveness of the use of CMV intake on the studied tobacco varieties was a cumulative comparative analysis of the following indicators of control (without CMV sheet) and experimental samples: the level of drying intensification, indicators of commercial quality, technological properties and chemical composition of the obtained raw materials. It is established that CMV allows to intensify the drying process by 1,3–2,46 times, depending on the tobacco variety and has a positive effect on the technological properties of raw materials, most varieties increase the yield of fiber and retain volume-elastic properties. The dynamics of drying affects the change in the chemical composition of raw materials. During the drying process, due to the hydrolysis of nicotine salts and its release by oxidation with air oxygen, the nicotine level in a number of samples decreases within 10–30%. The higher the nicotine content, the higher the strength of tobacco, it is coarser in taste. Changes in the carbohydrate-protein ratio in the direction of increasing carbohydrates improve the taste characteristics of raw materials. For each studied variety, it was not possible to identify a regular dependence of its structure and the nature of the drying process at CMV with transformations of the chemical composition of raw materials. Based on the analysis of technological and qualitative indicators of tobacco raw materials presented in the developed database on the intensification of drying of various varieties of tobacco using the use of CMV of tobacco leaves, it is possible to plan the choice of the optimal drying method for each variety of tobacco, which allows to increase the efficiency of using raw materials and improve its quality characteristics.

Phyllospheric Microbial Composition and Diversity of the Tobacco Leaves Infected by Didymella segeticola

A Myriad of biotic and abiotic factors inevitably affects the growth and production of tobacco (Nicotiana tabacum L.), which is a model crop and sought-after worldwide for its foliage. Among the various impacts the level of disease severity poses on plants, the influence on the dynamics of phyllospheric microbial diversity is of utmost importance. In China, recurring reports of a phyto-pathogen, Didymella segeticola, a causal agent of tobacco leaf spot, accentuate the need for its in-depth investigation. Here, a high-throughput sequencing technique, IonS5TMXL was employed to analyze tobacco leaves infected by D. segeticola at different disease severity levels, ranging from T1G (least disease index) to T4G (highest disease index), in an attempt to explore the composition and diversity of phyllospheric microbiota. In all healthy and diseased tobacco leaves, the most dominant fungal phylum was Ascomycota with a high prevalence of genus Didymella, followed by Boeremia, Meyerozyma and Alternaria, whereas in the case of bacterial phyla, Proteobacteria was prominent with Pseudomonas being a predominant genus, followed by Pantoea. The relative abundance of fungi, i.e., Didymella and Boeremia (Ascomycota) and bacteria, i.e., Pseudomonas and Pantoea (Proteobacteria) were higher in diseased groups compared to healthy groups. Healthy tissues exhibited relatively rich and diverse fungal communities in contrast with diseased groups. The infection of D. segeticola had a complex and significant effect on fungal as well as bacterial alpha diversity. FUNGuild analysis indicated that the relative abundance of pathotrophs and saprotrophs in diseased tissues proportionally increased with disease severity. PICRUSt analysis of diseased tissues indicated that the relative abundance of bacterial cell motility and membrane transport-related gene sequences elevated with an increase in disease severity from T1G to T3G and then tended to decrease at T4G. Conclusively, the current study shows the typical characteristics of the tobacco leaf microbiome and provides insights into the distinct microbiome shifts on tobacco leaves infected by D. segeticola.

Data Research on Tobacco Leaf Image Collection Based on Computer Vision Sensor

In the process of tobacco silk making, how to better improve the quality of stem and leaf separation has become an issue of concern. His research mainly discusses the data collected from tobacco leaf images based on computer vision sensors. In LM (Levenberg-Marquarelt) as a training function, the algorithm uses threshing effect samples for training and learning. This paper is aimed at extracting the shape characteristic parameters of tobacco leaves and obtains the shape parameters of the length, width, area, circumference, and roundness of the tobacco leaves. In this paper, boundary tracking is used to obtain the coordinate and direction information of the tobacco leaf boundary pixels in the image, which provides a basis for obtaining the subsequent extraction of tobacco leaf characteristic parameters. In the tobacco leaf grading system, the tobacco leaf feature parameter extraction module displays the geometric characteristics of tobacco leaf, such as length, width, area, aspect ratio, rectangularity, and color characteristic, hue H , saturation S , A channel, and B channel in detail through the computer vision sensor. Finally, the subjective and objective combination weighting method is used to combine and weight the indicators of the threshing effect of the first-level threshing machine, which not only considers the quantity of information provided by the indicators but also takes into account the subjective view of the experts, which increases the weight of the indicators, accuracy, and scientificity. The approximation accuracy of the training samples of the threshing effect prediction model based on the BP neural network LM algorithm is 99.495%, the approximation accuracy of the validation set is 96.535%, and the approximation accuracy of the test set is 98.392%. This research will greatly improve production efficiency and meet the enterprise’s requirements for high efficiency and low cost.

Response of Intermediate Ripening Tobacco (Nicotiana tabacum) Cultivars to Frog Eye (Cercospora nicotianae) and Alternaria Leaf Spot (Alternaria alternata) in the Medium Growing Areas of Zimbabwe

Background: Alternaria leaf spot (Alternaria alternata) and Frog eye leaf spot (Cercospora nicotianae) are foliar diseases of tobacco (Nicotiana tabacum) which occur mainly in mature tobacco. Hence, the diseases are often associated with maturity of cured tobacco leaf at the tobacco sales floor in Zimbabwe. Where they occur, they can result in significant reductions in yield and quality of cured tobacco leaf. Methods: A study was carried out in Trewaney, Mashonaland West province in Zimbabwe to investigate the response of newly developed ten flue cured tobacco varieties to the two foliar diseases Alternaria leaf spot (Alternaria alternata) and frog eye leaf spot (Cercospora nicotianae). The experiment was laid out as a randomized complete block design (RCBD) with three replicates. Standard agronomic practices in tobacco farming were followed and disease assessments were done 18 weeks after planting. Result: Significant differences (p less than 0.05) for resistance to alternaria leaf spot were observed with the experimental hybrid T60 showing the highest resistance to the disease with a disease score of 1.6 under a 0-6 disease scale that ranges from 0 (no disease) to 6 (severely affected). However, there were no significant (p greater than 0.05) differences among the varieties for frog eye leaf spot resistance, yield (kg/ha) and quality as measured by the grade index, however, K 326 showed the highest resistance to frog eye leaf spot. All the varieties, however, showed resistance to the two diseases. It was concluded that K 326 was the source of the resistance to frog eye leaf spot in all the experimental hybrids evaluated and that T60 had the highest Alternaria leaf spot resistance obtained from its parents which are both classified as resistant to the disease.

Heat Triggered Release Behavior of Eugenol from Tobacco Leaf

Fragrance is a commonly used substance in a number of commercial products, and fine control over the release behavior of the fragrance is essential for its successful application. Understanding the release behavior of the fragrance is the key to realizing the control of its release. Herein, we use tobacco leaf as the model substrate and investigate the mechanism of eugenol release from tobacco leaf. Our results show that interaction between eugenol and tobacco leaf is weak physical adsorption, and the eugenol release from tobacco leaf substrate is a temperature-dependent process. Further analysis on the release behavior reveals that eugenol release is closely associated with the morphology change of tobacco leaves under heating conditions. Our results provide insight into the release mechanism of fragrance from polymer substrate and may be useful for the future design of fragrance release systems.

Bio-efficacy of Plants based Formulations for the Management of Cowpea Aphid (Aphis craccivora Koch.)

Background: The cowpea (Vigna unguiculata) is damaged by various insect pests of which cowpea aphid (Aphis craccivora) causes heavy damage to the tender leaves of the plant and reduces its yield. Two plant based formulation (prepared in the Chemistry Laboratory) viz. Polygonum hydropiper floral parts and Tobacco (Nicotiana tabacum) leaf, were used for safe management. Methods: The studies were done during 2019-2020 in BCKV, Kalyani, West Bengal, India for controlling of cowpea aphid by using plant based formulation. For preparing wettable powder formulation from Polygonum hydropiper floral parts and tobacco leaf the different ingredients are required viz. china clay, silica gel, wetting agent, dispersing agent etc. Physico-chemical analysis was done for preparation of accurate Wettable Powder formulation. Result: Cowpea aphid causes damage the tender leaves of the plant. It was revealed that imidacloprid (Confidor 17.8 SL) @ 1.0 ml/3L was found the most effective treatment against aphids giving more than 80% control followed by tobacco leaf (50 WP) @ 8 g/L of water (more than 70% control), fipronil (Regent 5% SC) @ 2.5 ml/L of water and Polygonum floral parts (50 WP) @ 8 g/L of water (more than 65% control both). The quality parameters of WP (50%) formulation was satisfactory as per the FAO specifications in terms of wet sieved test, wettability, foaming and suspensibility performed on the 0-day and also after 15th day at room temperature, at 65°C and at freezing temperature conditions.

Leaf Plasmodesmata Respond Differently to TMV, ToBRFV and TYLCV Infection

Macromolecule and cytosolic signal distribution throughout the plant employs a unique cellular and intracellular mechanism called plasmodesmata (PD). Plant viruses spread throughout plants via PD using their movement proteins (MPs). Viral MPs induce changes in plasmodesmata’s structure and alter their ability to move macromolecule and cytosolic signals. The developmental distribution of a family member of proteins termed plasmodesmata located proteins number 5 (PDLP5) conjugated to GFP (PDLP5-GFP) is described here. The GFP enables the visual localization of PDLP5 in the cell via confocal microscopy. We observed that PDLP5-GFP protein is present in seed protein bodies and immediately after seed imbibition in the plasma membrane. The effect of three different plant viruses, the tobacco mosaic virus (TMV), tomato brown rugose fruit virus (ToBRFV, tobamoviruses), and tomato yellow leaf curl virus (TYLCV, begomoviruses), on PDLP5-GFP accumulation at the plasmodesmata was tested. In tobacco leaf, TMV and ToBRFV increased PDLP5-GFP amount at the plasmodesmata of cell types compared to control. However, there was no statistically significant difference in tomato leaf. On the other hand, TYLCV decreased PDLP5-GFP quantity in plasmodesmata in all tomato leaf cells compared to control, without any significant effect on plasmodesmata in tobacco leaf cells.