Evaluation of Different Substrates Compositions for Acclimatization of Tissue Culture Taro Plantlets in a Propagator

Taro is cultivated in most Regions of Cameroon and it is affected by taro leaf blight disease since 2010 which has decreased its production. Lack of disease-free planting materials has been a main problem to farmers. This study was carried out at International Institute of Tropical Agriculture (IITA) Yaounde and Institute of Agricultural Research for Development (IRAD) Bambui to assess different substrates for acclimatization of tissue culture taro plantlets in apropagator. No information is available on acclimatization of Cameroonian taro plantlets in different substrates. Taro plantlets from tissue culture were acclimatised in a propagator for six weeks under different substrates, the first substrate consisted of sterile three parts of soil and one part of river sand mixed together (3:1), the second substrate consisted of sterile two parts of soil and two parts of river sand mixed together (2:2), the third substrate consisted of sterile two parts of soil, one part of rice husk and one part of river sand mixed together (2:1:1) and the fourth substrate consisted of sterile one part of soil and three parts of river sand mixed together (1:3). After acclimatisation of the different taroplantlets (Dark green petiole with small leaves (L1), Red petiole with small leaves (L2), Light green petiole with large leaves (L3) and Light green petiole with small leaves (L4) in these four substrates, it was observed that the best growth rate of plant was recorded on substrate sand + soil (1:3). The other substrates showed moderate growth of plants. Substrate sand + soil (1:3) can be recommended for acclimatization of Cameroonian taro plantlets.

Comparative Study on the Efficacies of 11 Chemical Agents against Taro Soft Rot Caused by Pectobacterium aroidearum

[Objective]The paper was to screen the effective agents for effectively controlling the occurrence and prevalence of taro soft rot.[Method]The fungicidal effects of 11 fungicides on taro soft rot were determined by inhibition zone method.[Result]0.3%Tetramycin,25%bromothalonil,3%Zhongshengmycin and 30%zinc thiazole had better antifungal effect on Pectobacterium aroidearum at recommended concentration.The indoor toxicity of four fungicides showed that the EC50 of 0.3%tetramycin AS was the smallest of 0.6μg/mL,indicating that tetramycin had the largest toxicity and the best inhibitory effect against P.aroidearum;followed by 25%bromothalonil EC and 3%Zhongshengmycin WP,with the EC_(50) of 2.57 and 97.72μg/mL,respectively;the inhibitory effect of 30%zinc thiazole SC against P.aroidearum was the poorest.[Conclusion]The study provides a reference for screening out new and efficient chemical agents against taro soft rot.

Effect of Different Concentrations of Orange Juice for in Vitro Regeneration and Multiplication of Cocoyam (Taro)

Taro (Colocasia esculenta) and tannia (Xanthosoma sagittifolium) are commonly referred to as cocoyam in Nigeria. They are cherished for their rich taste, nutritional and medicinal properties. Traditionally, cocoyams are vegetatively propagated from tuber fragments, a practice that encourages pathogen distribution. For rapid multiplication and production of quality planting materials, tissue culture technology offers promising alternative compared to the traditional production methods. In this study different concentrations of ripped sweet orange (Citrus sinensis) juice were screened for regeneration and multiplication of 2 months old in vitro cocoyam shoot explants. Among the concentrations, maximum numbers of roots (37 ± 5) were observed in Murashige and Skoog (MS) medium supplemented with 10% orange juice after 8 weeks in culture compared to 16 ± 4 (roots) observed in the control medium. On shoot multiplicity, 16 ± 3 shoots were induced in the control medium in contrast to 12 ± 0.8 shoots in the MS medium supplemented with 10% orange juice after 8 weeks of culture. Higher concentrations (25% and 35%) of the orange juice supplemented medium resulted in concomitant inhibition of all the growth parameters. The study successfully established that ripped orange juice could substitute the use of conventional growth hormones cytokinins (BAP) and auxins (NAA) in in vitro regeneration and rapid multiplication of cocoyam shoot explants.

Effect of Processing on the Oxalate and Calcium Concentrations of Two Local Dishes, Cơm Hến and Canh Chua Bạc Hà, Prepared from Taro Stems

Stems of sweet taro (Colocasia esculenta) grown in Thua Thien HuếProvince in Vietnam and were used as an ingredient to prepare two local dishes, Cơm Hến and Canh Chua Bạc Hà. This study investigated the effect of simple processing treatments used to prepare these popular dishes on the total, soluble and insoluble oxalate and calcium contents of the taro stems. Raw stems were used to prepare Cơm Hến. Three treatments, removing the skin then washing and slicing, slicing and washing, or slicing and then allowing the stems to wilt overnight were compared to the whole raw stems with the skin retained. Overall, processing the stems reduced the soluble oxalate contents by a mean of 8% when compared with the original raw stems. The mean total calcium bound in the insoluble oxalate fraction of the three processing treatments was 43.3% ± 2.0%. Canh Chua Bạc Hà was prepared by boiling peeled taro stems. In this experiment the peeled stems were boiled for 10, 15 and 20 min and this resulted in 63.4%, 74.5% and 76.6% reductions in soluble oxalate content, respectively, when compared to the original peeled stems. Boiling for 20 min was the most effective way to reduce both the total and soluble oxalate contents of the stems. 39% of the total calcium in the raw taro stems was bound to the insoluble oxalate fraction and this was reduced to a mean of 17.2% ± 2.6% by the three cooking treatments.

Fluorine in Water and Dental Fluorosis in a Community of Queretaro State Mexico

The community La Llave, Queretaro State, Mexico, has not been identified by the sanitary authorities as living in a hazard area related to dental fluorosis. However;a high concentration of fluoride is found in their drinking water causing them dental fluorosis. Physical-chemical analysis was carried out in the groundwater sources to determine the prevalence of dental fluorosis risk and caries accordingly to criteria of The World Health Organization, and 154 school children of ages 10 to 13 years were examined. As a result, 1.9 mg/L of fluorine concentration in drinking water was obtained;dental fluorosis presence was detected in the school children with an incidence of about 98%, in 47% of cases severe fluorosis with a dental caries index of 3.06 was traced. The groundwater sources in La Llave community contains fluorine above the limits dictated by Mexican regulations, producing serious repercussions on the health of school children, with an unnaturally high incidence of dental fluorosis.

Control Effect and Application Technology of Mandipropamid on Red Taro Blight

The field experiment results showed that 250 g/l mandipropamid suspension had good control effect on red taro blight,and the 1∶1500 suspension was applied twice continuously during the early period( June 25) and culmination period( July 12) of taro blight; the control effect 23 d after the last application reached 79. 28%,significantly better than that of conventional pesticide,and it was safe,so it had good prospects for the development and application in production.

Effect of Pre-Gelatinization Conditions on the Total Oxalate Content and Techno-Functional Properties of Taro (Colocasia esculenta) Flour

Like most roots and tubers, taro (Colocasia esculenta) corms have a short shelf-life due to the high moisture content, which aggravates their post-harvest losses. They also contain high amounts of calcium oxalates, limiting their use in food applications. To help add value and diversify the use of taro corms as well as curb food losses, various strategies have been proposed, such processing of the corms into flour. This study aimed at evaluating the total oxalate content and techno-functional properties of taro flour as affected by the pre-gelatinization conditions (i.e., method and time). Pre-gelatinized taro flour was prepared by subjecting peeled and cleaned taro corms to roasting (190°C), boiling (100°C), and steaming (100°C) for 10 min, 20 min and 30 min, respectively, for each method, followed by drying at 55°C and milling. Generally, all the properties of flour were significantly affected by the pre-gelatinization conditions (P 0.05). The total oxalate content of the pre-gelatinized taro flour ranged from 33.26 to 76.90 mg/100g. Pre-gelatinization by boiling significantly reduced the oxalate content (56.7%), while roasting resulted in the least reduction (36.2%). The flour colour i.e. L*, hue, and chroma ranged from 38.47° - 70.30°, 42.64° - 69.43°, and 7.78° - 10.58°, respectively. Roasting resulted in flour with the largest L* (70.30°) and hue angle (69.43°). Boiling also resulted in flour with the highest bulk density (BD) (0.86 g/cm3) and the lowest water solubility index (WSI) (9.39%). Steamed flour had the highest water absorption index (WAI) (3.81 g/g), water holding capacity (WHC) (4.59 g/g), and swelling capacity (SC) (4.86 g/g). This study shows that pre-gelatinization (i.e. by boiling, steaming or roasting) significantly affects the total oxalate content and techno-functional properties of taro flour, which in turn influences its use in other food applications thus increasing the utilization and production of taro simultaneously.

Genetic Diversity of Taro Landraces from Côte d’Ivoire Based on Qualitative Traits of Leaves

Taro is an important crop species in Côte d’Ivoire. It is cultivated for its tubers and leaves. But its knowledge and genetic diversity and differentiation are very weakly documented. Several morphological types are found in rural area, but their identification is not very clear, and their agronomic potentiality is underexploited. In this context we initiated a survey and collected 213 accessions from 14 growing regions of Côte d’Ivoire. The diversity was evaluated based on seven qualitative traits of leaves (Shape of the base of the leaf, Predominant position (shape) of the leaf blade surface, Margin of the leaf blade, Leaf blade variegation, Profile of the petiolar junction, Shape of the leaf sheath, Shape of the appendix) during an experimentation conducted in rural area. The objective of this study was to characterize the collection of taros collected in different geographical zones of Côte d’Ivoire and identify the genera cultivated. Results of our study indicated that excepted margin of the leaf blade all traits are very discriminant. Several variants were observed for each of traits. According to observations and statistics analysis accessions were separated into two main groups. The characteristics of these groups indicate that taro cultivated in Côte d’Ivoire could belong to two genera: Xanthosoma and Colocasia.

Molecular Detection of Phytophthora colocasiae of Taro Leaf Blight Based on PCR

The present PCR assay was conducted to develop rapid and sensitive detection of Phytophthora colocasiae,in order to provide a robust and reliable tool for healthy seedling production of taro and limiting the transmission and spread of the causal organism of taro leaf blight in taro planting regions.The samples were used to extract total DNA and to be detected by PCR with P.colocasiae specific primer pairs PCSP-RL F/PCSP-RL R and PCSP-T F/PCSP-T R,respectively.Distinct fragments of about 200 bp and 240 bp were amplified by PCR using primers PCSP-RL F/PCSP-RL R and PCSP-T F/PCSP-T R,respectively.The analysis of the nucleotide sequence of the PCR products were found to be 99% identical to sequence of RAS-related protein (Ypt1) and phospho-ribosylanthranilate isomerase (TRP1) in P.colocasiae,respectively.It is concluded that rapid and sensitive developed PCR assay for detection of P.colocasiae could be used in routine diagnosis and aid in management practices to mitigate taro leaf blight.

Risk Assessment of Agricultural Products Supply-Chain Finance Based on D-S Theory

Agricultural products supply-chain finance, as one of the solutions to the issue of “capital problems” of agriculture, countryside and farmers, has proposed a kind of characteristics model to assess the risk of agricultural production, processing and marketing, which can improve the issue of farmers and enterprises lacking of funds. This model is proposed on the basis of uncertain information processing method of D-S theory and its data combination rules, combined with the “discount rate” correction model, and it includes a risk assessment index system of agricultural products supply-chain finance, fully considering the five aspects of production, processing, marketing, cooperation of supply chain and collateral. At last, a taro supply chain is taken for example. And the risk assessment of its supply-chain finance based on this model has been discussed in detail. And the result has proved that the model and its algorithm are practical and feasible.

芋圆的微波间歇干燥工艺研究

为保证芋圆的干燥效率与良好品质,试验选取芋圆直径、微波功率和间歇比为影响因素,以复水比、感官评分、熟化时间和干燥总时间这4个指标的隶属度综合评分为评价指标,通过单因素和响应面试验,对微波间歇干燥芋圆的工艺条件进行优化。结果表明,所选试验因素对隶属度综合评分影响大小顺序为芋圆直径>微波功率>间歇比;最佳工艺参数为芋圆直径0.8 cm、微波功率350 W、间歇比2.0。此条件下得到的干燥芋圆的品质最优,其隶属度综合评分为2.417±0.007。

木薯变性淀粉在芋圆制作中的应用研究

将木薯原淀粉、木薯醋酸酯淀粉、木薯羟丙基淀粉、木薯磷酸酯双淀粉以不同比例添加到芋圆中,探究不同淀粉对芋圆品质及其冷藏性能的影响,并对这四种淀粉的糊化特性、透明度和冻融稳定性进行分析研究。结果表明:木薯羟丙基淀粉具有良好的保水性、透明性和冻融稳定性。加水量为10%~15%,变性淀粉添加量为60%左右,此时芋圆的感官品质和冷藏稳定性最好。添加木薯羟丙基淀粉,不仅可以降低芋圆的失水率,而且在改善芋圆的透明度、光泽和色泽等方面的效果尤其明显。

Multitemporal landslide inventory analysis of an intertropical mountain in west-central Mexico——Basis for hazard management

Landslides in intertropical mountainous areas of Mexico are a natural hazard that could potentially generate a disaster. Despite this, many areas lack landslide inventories, making it difficult to monitor and efficiently manage the associated risks for local populations. For this reason, the aim of this research was to undertake a multitemporal landslide inventory and analyze its conditioning factors in the Pico de Tancítaro stratovolcano, which, in recent decades, has presented several high-risk geomorphological events with disastrous consequences for nearby localities. The spatial distribution of landslides and its conditioning factors were mapped at a 1:50,000 scale for the 1995-2020 period, through visual interpretation of orthophotos and satellite images(Landsat, SPOT, and SENTINEL). The conditioning factors that link the most to landslides were Quaternary andesite and basaltic andesite rocks;volcanic cones, mountain river valleys, and very steep to steep slopes(30° to >45°), oriented to the South, North, and East;Andosols and Leptosols;and the oyamel fir and mixed forests. 505 landslide events classified into slides and flows that occurred in 1995, 2004, 2010, and 2015 were identified. New scars generated by the reactivation of landslide processes were also observed. The landslides in the study area were triggered by torrential rains caused by hurricanes and tropical storms;such as hurricanes Alex and Patricia. The inventory and analysis of conditioning factors highlighted the distribution and dynamics of slides and flows in the study area. In addition, the most important factors for studies of landslide susceptibility, hazards, and risks in the Pico de Tancítaro stratovolcano were identified, contributing to the management of geomorphological risks in intertropical mountain areas.

识别手写字体自动建模书法机器人

基于大规模实时文字处理,海量文字录入以及模仿个人笔迹等应用需求,设计识别手写字体自动建模书法机器人,采用微信小程序与下位机结合的框架,通过与写字机器人上的8266Wi-Fi芯片建立WebSocket进行数据通信。基于OpenCV的轮廓检测进行字符提取,通过训练分类器和样本文件识别文字。采用onActivityResult回调处理,实现拍照录入字体,基于Taro+React框架适配不同小程序平台,完成手写字体的识别与自动建模。写字机器人机械结构采用Hbot机械控制结构,采用前梯形加减速控制与Bresenham直线算法相结合实现对机构的运动速度规划。经过对识别系统的600次测试,字库识别准确率可达92%,模仿笔迹自动建模准确率可达83%。

Antiproliferative piperidine alkaloids from giant taro(Alocasia macrorrhiza)

The rhizome of giant taro(Alocasia macrorrhiza(L.)Schott),which is a highly adaptable wild plant,is a traditional Chinese herbal medicine.In the current study,the antiproliferative constituents of giant taro were investigated and six new(1−6)and four known piperidine alkaloids(7−10)were isolated from its rhizomes.Their chemical structures and absolute configurations were elucidated using various spectroscopic methods and the Mosher ester method.The isolated alkaloids were screened for the antiproliferative activity through MTT assay.The results indicated that piperidine alkaloids exerted potential antiproliferative activity against HepG2,AGS and MCF-7 tumor cells.Further researches showed that compounds 3−5 dose-dependently decreased the colony formation rate and induced the apoptosis of AGS cells,while compound 4 induced AGS cell death via the proapoptotic pathway.This study demonstrates that the piperidine alkaloids isolated from giant taro exhibit significant antitumor activity,which provides phytochemical evidence for further development and utilization.

An easy-to-implement method for fabricating superhydrophobic surfaces inspired by taro leaf

An easy-to-implement method by which to fabricate superhydrophobic surfaces inspired taro leaf was successfully applied on316 L stainless steel via combining nanosecond laser(NL)processing and spin-coating techniques.The laser-textured surface composed of microscale frameworks and central bumps was fabricated by NL processing based on properly designed biomimetic patterns,and a layer of nanoscale carbon black/polydimethylsiloxane(CB/PDMS)particles was covered on it by spin-coating.The effect of pattern parameters(i.e.,the inscribed circle radius of framework and the radius of central bump)on wettability of biomimetic surface was investigated.All as-prepared biomimetic surfaces with micro-nano hierarchical structures showed excellent superhydrophobicity with the water contact angle of~155°and contact angle hysteresis of~2°.By comparing the untreated surface,the wetting behavior and evaporation mode of the biomimetic surface occurred an obvious transformation.Meanwhile,experiments indicated that the biomimetic surface not only had liquid-repelling and self-cleaning functions,but also maintained remarkable mechanical robustness and superhydrophobic durability.The method is efficient for fabricating biomimetic superhydrophobic surfaces applied to liquid-repelling,evaporation-transforming and self-cleaning fields.

Sugar Coated Taro

Taro is smooth and sticky in texture and rich in fat,protein and sugar.According to Chinese traditional medicine, taro nourishes the spine and stomach and helps energy. Ingredients:500 grams taro (peeled and chopped into diamond-shaped cubes), 15 grams sugar. 250 grams vegetable oil. Method: 1. Heat oil in a wok and add taro cubes. Fry unti they turn golden brown. 2. Take out the taro with a sieve and pour the oil into a container for later use. Add sugar and one tablespoon oil.Stir continuously to prevent burning. When

即墨白庙芋头软腐病病原菌鉴定

芋头(Colocasia esculenta (L.) Schoot)属天南星科芋属单子叶多年生草本植物,是世界上分布最广的作物之一[1]。其地下块茎富含淀粉和各种微量矿物元素,在世界各地广泛种植,是一种深受人们喜爱的健康食品,并且在医药和观赏方面具有多种用途[2-3]。我国是世界芋头种植大国之一,各地区均有种植[4]。白庙芋头为山东即墨特产,有600余年的栽培历史。