Hasil untuk "Plant culture"

Ofir Katz, Ofir Katz, Mikhail S. Blinnikov et al.

Linjuan Huang, Luocan Zhou, Yandi Qin et al.

Aluminum (Al) toxicity in acidic soils severely restricts plant growth, particularly reducing the productivity of fast-growing timber species—Eucalyptus. Silicon (Si), a beneficial element, can alleviate Al toxicity, but its underlying mechanisms in tree species with contrasting Al tolerance remain unclear. Here, we investigated the effects of Si addition on plant growth, Al uptake, and rhizosphere microbial community and metabolic composition in an Al-sensitive species (Eucalyptus tereticornis) and an Al-tolerant species (Eucalyptus urophylla). Results showed that Al stress significantly inhibited the relative growth rates of roots, stems and leaves, and decreased photosynthetic efficiency. However, Si addition effectively reduced these adverse effects by increasing photosynthetic rate, pigment content, water use efficiency, electron transport rate, and maximum photochemical efficiency of PSII. Aluminum stress also increased soil water-soluble, inorganically bonded and exchangeable Al, promoting root Al accumulation, which was higher in E. urophylla than in E. tereticornis. Microbiome and metabolome analyses revealed species-specific mechanisms by which Si alleviates Al toxicity. In E. tereticornis, Si directly increased bacterial, fungal and metabolite diversity, which facilitated the immobilization of water-soluble and exchangeable forms into less bioavailable forms, including organically bonded, hydrates, and hydrous oxides, thereby reducing Al uptake and upward translocation. In E. urophylla, Si indirectly increased bacterial and metabolite diversity, and recruited specific microbial taxa, including Candidatus Solibacter, Acidothermus, and Occallatibacter, thereby promoting Al uptake, upward translocation and internal detoxification. Our findings reveal distinct Si-mediated mechanisms for alleviating Al toxicity in Eucalyptus, offering practical guidance for the management of Eucalyptus forests in acidic soils.

Laura Mathieu, Maxime Reder, Ali Siah et al.

Abstract Background Investigations on plant-pathogen interactions require quantitative, accurate, and rapid phenotyping of crop diseases. However, visual assessment of disease symptoms is preferred over available numerical tools due to transferability challenges. These assessments are laborious, time-consuming, require expertise, and are rater dependent. More recently, deep learning has produced interesting results for evaluating plant diseases. Nevertheless, it has yet to be used to quantify the severity of Septoria tritici blotch (STB) caused by Zymoseptoria tritici—a frequently occurring and damaging disease on wheat crops. Results We developed an image analysis script in Python, called SeptoSympto. This script uses deep learning models based on the U-Net and YOLO architectures to quantify necrosis and pycnidia on detached, flattened and scanned leaves of wheat seedlings. Datasets of different sizes (containing 50, 100, 200, and 300 leaves) were annotated to train Convolutional Neural Networks models. Five different datasets were tested to develop a robust tool for the accurate analysis of STB symptoms and facilitate its transferability. The results show that (i) the amount of annotated data does not influence the performances of models, (ii) the outputs of SeptoSympto are highly correlated with those of the experts, with a similar magnitude to the correlations between experts, and (iii) the accuracy of SeptoSympto allows precise and rapid quantification of necrosis and pycnidia on both durum and bread wheat leaves inoculated with different strains of the pathogen, scanned with different scanners and grown under different conditions. Conclusions SeptoSympto takes the same amount of time as a visual assessment to evaluate STB symptoms. However, unlike visual assessments, it allows for data to be stored and evaluated by experts and non-experts in a more accurate and unbiased manner. The methods used in SeptoSympto make it a transferable, highly accurate, computationally inexpensive, easy-to-use, and adaptable tool. This study demonstrates the potential of using deep learning to assess complex plant disease symptoms such as STB.

Zixuan Li, Chenyuan Mao, Xinyi Wu et al.

Hybridization is an important evolutionary mechanism ubiquitous to plants. Previous studies have shown that hybrid polyploidization of cultivated chrysanthemum, ‘Zhongshanzigui’, and Leucanthemum paludosum exhibit spring-flowering traits. This study explores the function of the LpFTLs gene via the phenotype of A. thaliana after heterologous transformation of the LpFTLs gene, and analyzes the mechanism ofthe continuous flowering phenotype and heterosis of hybrid offspring. The results suggest that the flowering phenotype of hybrid offspring in spring may be related to the expression of the LpFTLs gene. Ectopic expression of Leucanthemum paludosumLpFTLs in Arabidopsis thaliana resulted in earlier flowering, indicating that the LpFTLs gene also affects the flowering time in L. paludosum. Compound expression of FTLs in C. morifolium × L. paludosum intergeneric hybridization directly leads to serious heterosis in the hybrid offspring. Moreover, continuous flowering appears to be accompanied by hybrid weakness under the balance of vegetative and reproductive growth. Therefore, in future studies on chrysanthemum breeding, a suitable balance point must be established to ensure the target flowering time under normal growth.

David R. Benson, W. B. Silvester

Frankia strains are N2-fixing actinomycetes whose isolation and cultivation were first reported in 1978. They induce N2-fixing root nodules on diverse nonleguminous (actinorhizal) plants that are important in ecological successions and in land reclamation and remediation. The genus Frankia encompasses a diverse group of soil actinomycetes that have in common the formation of multilocular sporangia, filamentous growth, and nitrogenase-containing vesicles enveloped in multilaminated lipid envelopes. The relatively constant morphology of vesicles in culture is modified by plant interactions in symbiosis to give a diverse array of vesicles shapes. Recent studies of the genetics and molecular genetics of these organisms have begun to provide new insights into higher-plant-bacterium interactions that lead to productive N2-fixing symbioses. Sufficient information about the relationship of Frankia strains to other bacteria, and to each other, is now available to warrant the creation of some species based on phenotypic and genetic criteria.

Efstratios Guillaume Xyrafis, Alain Deloire, Despoina Petoumenou et al.

Own-rooted and phylloxera-free vines have been cultivated on the volcanic soil of Santorini for thousands of years. All this time, vines have been cultivated by using two traditional training systems, the ‘Κouloura’, and the ‘Κladeftiko’, which are well-adapted to the specific climatic conditions of the island. This first report aims to share the scarce existing knowledge on Santorini’s training and pruning systems, looking at some important quantitative and qualitative ripening parameters over four consecutive seasons (2017-2020) and revealing similarities regarding their adaptation to climate conditions on the island.

J. Pospóšilová, I. Tichá, P. Kadlecek et al.

German Sandoya, Jesse J. Murray, Richard N. Raid et al.

Fusarium wilt of lettuce is a disease caused by the fungus Fusarium oxysporum f.sp. lactucae. The disease is present in all lettuce production areas worldwide. Recently this disease has been identified in Florida in localized fields. This new 4-page publication of the UF/IFAS Horticultural Sciences Department presents information about the disease, symptoms, and control measures useful to lettuce growers in Florida. Following these recommendations may help to avoid the spread of this fungus in muck soils at the Everglades Agricultural Area (EAA), where 90% of the lettuce in Florida is planted. Written by Germán V. Sandoya, Jesse J. Murray, Richard N. Raid, and Christian F. Miller. https://edis.ifas.ufl.edu/hs1385

Josh H Freeman, Eugene J. McAvoy, Nathan S. Boyd et al.

This chapter covers production of cucurbits, such as cantaloupe, cucumber, squash, watermelon, and pumpkin. Accessibility Summary: In accordance with Title II regulations this content meets all points of exemption as Archived web content and/or Preexisting conventional electronic documents.

Agus Budi Setiawan, Aziz Purwantoro, Ari Wibowo

The genus Cucumis including timun suri, melon and cucumber, is an important horticultural crop of flowering plants. The dispute of timun suri terminology is leading to false-positive results in the nomenclature of timun suri in Indonesia. Although molecular research on these species has been widely conducted, detailed information and precise evidence based on the molecular cytogenetic approach are poorly investigated. The FISH technique was applied to reveal the cytological distinctions among these species. Here, this research conducted physical mapping of 45S ribosomal DNA (rDNA) on six accessions of Cucumis. The chromosome number of cucumber is 14 chromosomes, while timun suri and melon are 24 chromosomes. The number of 45S rDNA loci in cucumber, melon and timun suri was highly conserved. All cucumber accessions in this study had nine to ten 45S rDNA loci with strong and weak signal intensities located at proximal regions of the short arms. In melon and timun suri the signals of two pairs of 45S rDNA were located at the terminal and interstitial regions of the short arms. These were clear shreds of evidence to confirm that timun suri was cytogenetically closed to melon instead of cucumber. It confirmed that timun suri cannot be classified as a cucumber

maria Beihaghi, Abdolreza Bagheri, hasan marashi et al.

Introduction: Plant tissue culture is a collection of techniques used to maintain or grow plant cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition and widely used to produce clones of a plant in a method known as micropropagation. Plant research often involves growing new plants in a controlled environment. These may be plants that we have genetically altered in some way or may be plants of which we need many copies all exactly alike. These things can be accomplished through tissue culture of small tissue pieces from the plant of interest. These small pieces may come from a single mother plant or they may be the result of genetic transformation of single plant cells which are then encouraged to grow and to ultimately develop into a whole plant. Tissue culture techniques are often used for commercial production of plants as well as for plant research. Tobacco (Nicotiana tabacum L.) is one of the most important model plants used in the physiologic, genetic and tissue culture studies. The manipulation of tobacco genetic structure requires an efficient technique of gene transferring and regeneration. Whereas, the tobacco plant is a very effective bioreactor in the production of recombinant proteins, in this research we optimized the best tissue culture system and also, genetic transformation process of this plant. Materials and Methods: Our plant tissue culture protocols, Include helpful information for Murashige and Skoog media, plant growth regulators, plant growth hormones, plant transformation systems, and other products for plant tissue culture. For this purpose, different concentrations of sucrose and 4 combinations of growth regulators (BAP and NAA) on callus induction, direct shoot regeneration and rooting were examined in a factorial experiment based on completely randomized design with 3 replications. The sensitivity of tobacco explants to kanamycin was examined through the cultivation of them on the selective medium with different concentrations of antibiotic. For genetic transformation, agrobacterium tumifacious (GV3101) harboring plasmid pBI121 was used and the transgenic plants were confirmed by PCR analysis. Results and Discussion: The results of variance analysis and the means comparison showed that the best medium for callus induction was M1 (0.1 mg/l NAA and 1 mg/l BAP) with 15 g/l sucrose in the leaf explants, while the most direct shoot regeneration rate was obtained on the M1 medium with 30 g/l sucrose concentration. High-frequency of rooting was also influenced by 0/1 mg/l NAA and 60 g/l sucrose. So, supplementing the medium with NAA and BAP at different concentrations facilitated induction of multiple shoots from explants. NAA was proved to be the best and the number of shoots increased with increase in the concentration up to (0.1 mg/l), and exceeding this concentration resulted in decline in percent response as well as number of shoots was recorded shoot regeneration. The concentration of BAP was further increased a linear increase in the number of shoots was observed up to an optimal level (1 mg/l). Beyond the optimal concentration (1 mg/l), a decrease in the response as well as number of shoots was recorded due to profuse basal callusing. The effect of cytokinins on multiple shoot regeneration, higher concentrations of NAA found to be inhibitory for shoot regeneration because of huge callusing which hampered the growth and development of new shoots. Also different concentrations of sucrose have a different effect on the shoots and callus. The concentration of sucrose had significant effect on direct shoot regeneration. The main effect of sucrose concentration, concentration of 30 grams per liter, compared with a concentration of 15 grams per liter had the highest direct shoot regeneration. Concentration of 50 mg/l kanamycin could completely prevent the regeneration of untransformed explants so was used in the selective culture medium. Subsequently, the presence of nptII gene (798 bp) in the transgenic plants was confirmed and the transformation efficiency obtained by using the agrobacterium-mediated transformation was more than 95%. Conclusions In present research, an efficient in vitro regeneration protocol has been developed for tobacco, where different factors including the age of the explant and plant growth regulators were optimized for maximum propagation of tobacco. The results showed that regeneration and transformation method described here is highly efficient and fast for the introduction of any foreign gene directly in tobacco plant.

Michael T. Olexa, Tatiana Borisova, Jarrett Davis

La Ley del Agua de la Florida de 2016 es una política de agua integral que aborda los problemas críticos de abastecimiento de agua y calidad de la Florida. Entró en vigor el 1 de julio de 2016. La Ley del Agua de la Florida de 2016 creó la Ley de Protección de Acuíferos y Manantiales de Florida, codificó la Iniciativa de la Florida Central y revisó la Ley de los Everglades y Estuarios del Norte.

Nicole Benda, Adam G. Dale

Resistance to insecticide or miticide is a worry for landscape managers. Around the world, chinch bugs, leafminers, and other insect and mite pests have become resistant to dozens of insecticides, but with diligent insecticide resistance management, we can still maintain long-term effective chemical control. With few new modes of action coming onto the market, landscape managers need to be good stewards of existing products. Ultimately, resistance management means reducing exposure of pests to any one pesticide. Fortunately, there are many ways to prevent resistance and still control pests of ornamental plants and lawns, and this 6-page fact sheet written by Nicole Benda and Adam Dale and published by the UF/IFAS Entomology and Nematology Department explains how. http://edis.ifas.ufl.edu/in714

Zeinab J. Aawad, Ekbal H. Al- Khateeb

The present study was performed using the tissue culture technique , where by roots formation was stimulated shoot tips of Digitalis  purpurea L plant using auxins in this study ,shoot tips (1cm length ) were excised from sterilized seedlings of Digitalis purpurea L.Var Excelsior mixed , then they were cultured on MS medium with the addition of one of the auxins IAA, IBA  ,NAA of different concentration ( 0.0 ,0.05 ,0.1 ,0.5 and 1.0 mg / L ).  After 45 days of starting the culture results showed that the treatment 0.5 mg/ L of IBA had a high significant effect on the dry weight of roots formation and containing Digitoxin and Gitoxin whose quantities as a rate of ( 2.96 gm , 30.01 and 11.05 mg/gm dry weight respectively .Also this treatment has given highest values with the other studied characteristics where the percent of the soluble sugars and starch and they are ( 2.48 % , 2.82%) respectively  Abbreviation  (Indole Butyric Acid )IBA , ( Indole Acetic Acid )IAA ,  ( Murashige and skoog medium , 1962 )  MS ,  (Naphthalen acetic Acetic )  NAA  , ( Milligram ) Mg , ( Microgram )ug , (Litter ) L , (Gram) gm .

W.S.I. de Silva, M.M.N. Perera, K.L.N.S. Perera et al.

The promoter region of a drought and abscisic acid (ABA) inducible gene, osr40c1, was isolated from a salt-tolerant indica rice variety Pokkali, which is 670 bp upstream of the putative translation start codon. In silico promoter analysis of resulted sequence showed that at least 15 types of putative motifs were distributed within the sequence, including two types of common promoter elements, TATA and CAAT boxes. Additionally, several putative cis-acing regulatory elements which may be involved in regulation of osr40c1 expression under different conditions were found in the 5′-upstream region of osr40c1. These are ABA-responsive element, light-responsive elements (ATCT-motif, Box I, G-box, GT1-motif, Gap-box and Sp1), myeloblastosis oncogene response element (CCAAT-box), auxin responsive element (TGA-element), gibberellin-responsive element (GARE-motif) and fungal-elicitor responsive elements (Box E and Box-W1). A putative regulatory element, required for endosperm-specific pattern of gene expression designated as Skn-1 motif, was also detected in the Pokkali osr40c1 promoter region. In conclusion, the bioinformatic analysis of osr40c1 promoter region isolated from indica rice variety Pokkali led to the identification of several important stress-responsive cis-acting regulatory elements, and therefore, the isolated promoter sequence could be employed in rice genetic transformation to mediate expression of abiotic stress induced genes.

Dr. Amanullah, Shams-ul-Tamraiz Khan, Asif Iqbal

The objective of this research was to evaluate the impact of organic sources (animal manures vs. plant residues at the rate of 10 t ha-1 each) on the productivity profitability of small land rice (Oryza sativa L.) grower under different levels of phosphorus (0, 30, 60 and 90 kg P ha-1) fertilization. Two separate field experiments were conducted. In experiment (1), impact of three animal manures sources (cattle, sheep & poultry manures) and P levels was studied along with one control plot (no animal manure and P applied) as check was investigated. In experiment (2), three plant residues sources (peach leaves, garlic residues & wheat straw) and P levels was studied along with one control plot (no plant residues and P applied) as check. Both the experiments were carried out on small land farmer field at District Swabi, Khyber Pakhtunkhwa Province (Northwest Pakistan) during summer 2015. The results revealed that in both experiments the control plot had significantly (p≤0.05) less productivity than the average of all treated plots with organic sources and P level. The increase in P levels in both experiments (animal manure vs. plant residues) had resulted in higher rice productivity (90 = 60 > 30 > 0 kg P ha-1). In the experiment under animal manures, application of poultry manure increased rice productivity as compared with sheep and cattle manures (poultry > sheep > cattle manures). In the experiment under plant residues, application of peach leaves or garlic resides had higher rice productivity over wheat straw (peach leaves = garlic residues > wheat straw). On the average, the rice grown under animal manures produced about 20% higher grain yield than the rice grown under crop residues. We concluded from this study that application of 90 kg P ha-1 along with combined application of animal manures especially poultry manure could increase rice productivity. We conclude from this study that application of 90 kg P ha-1 along with combined application of animal manures, especially poultry manure, increases rice productivity. Also, the use of either garlic residues or peach leaves, never applied before as organic manures, can increase crop productivity

Adriana Barbosa Costa, Adolfo Marcito Campos de Oliveira, Ana Mara de Oliveira E Silva et al.

Na busca pela identificação de novas fontes de antioxidantes naturais e de esclarecer lacunas acerca das reais propriedades benéficas atribuídas ao Noni (Morinda citrifolia Linn), este trabalho teve como objetivo realizar a caracterização química e avaliar a atividade antioxidante da polpa, casca e sementes do noni. Foram determinadas a composição centesimal (umidade, cinzas, proteínas, carboidratos e lipídios); os compostos bioativos (fenólicos totais, carotenoides totais e vitamina C) e a atividade in vitro em extratos aquoso, etanólico e acetônico. Os resultados demonstraram que o Noni possui quantidades significativas de carboidratos (27,21%; 9,70% e 8,37%) e de proteínas (2,64%; 2,23%; e 2,24%) nas sementes, casca e polpa, respectivamente. A polpa apresentou maior teor de vitamina C (23,1 mg/100g) e de carotenoides totais (3,90 mg/100g). No extrato acetônico da polpa, foram quantificados 109,81 mg/100g de fenólicos totais, seguidos pelos extratos acetônicos da casca (76,01 mg/100g), das sementes (28,75 mg/100g) e do extrato etanólico da polpa (20,33 mg/100g). Todos os extratos avaliados apresentaram atividade antioxidante in vitro; os extratos acetônico e etanólico da casca e das sementes do Noni apresentaram maior atividade pelo método β-caroteno/ ácido linoleico, enquanto o extrato etanólico da polpa teve maior atividade antioxidante pelo ensaio DPPH e ABTS, e o extrato acetônico da polpa, pelo método ABTS. O noni é um fruto com significativo teor de compostos fenólicos totais que apresentam atividade antioxidante in vitro.

H. Hoffmann, T. Rath

Neeta D. Salvi, L. George, S. Eapen

N. Trolinder, J. Goodin