Notulae Botanicae Horti Agrobotanici Cluj-Napoca
Not a member yet
2546 research outputs found
Sort by
NIRS and multivariate methods for discrimination of morning glory species at different growth stages
Get PDFMorning glory species are weeds very common in tropical crops, where they cause direct and indirect damage. The management of these species primarily relies on the application of herbicides, disregarding the growth stage and spatial distribution. Studies addressing new techniques for identifying these species may contribute to the development of proximal sensors for carrying out specific and rational management. Thus, the objective of this work was to use near infrared spectroscopy (NIRS) and multivariate analysis to discriminate two species of morning glory in three growth stages. NIRS spectra were collected from Ipomoea hederifolia and Merremia aegyptia were collected at three different stages in the spectral range of 4.000 to 10.000 cm-1. PCA and PC-LDA were used to analyze the entire spectrum and specific bands. NIRS associated with PCA and PC-LDA were sufficient to discriminate I. hederifolia and M. aegyptia species and their growth stages. PCA allowed a proper segregation of stages and species when applied individually PC-LDA correctly classified between 90.93 to 100% of species and stages. The best discrimination results were observed in the NIR spectra ranges from 4.500 to 6.000 cm-1 and 4.500 to 6.000 + 6.500 to 7.750 cm-1. This study represents an advance in the research and implementation of NIRS technology to discriminate weed species for the future development of equipment to assist in the adoption and/or performance of a specific management of weeds, capable of contributing to the reduction in the use of herbicides in crops
Physiological responses and adoptive mechanisms in oat against three levels of salt stress
Get PDFTo identify the propagation mechanisms and the adaptive strategies of oat seedlings exposed to NaCl, NaHCO3 and Na2CO3 the main salts in the soils of the salt-alkali grasslands of the Songnen Plain of China, growth rates and physiological indices of oat seedlings were measured in plants grown in soils with different concentrations (48-144 mmol L-1) of the three salts. The results demonstrated that although oat seedlings survival rates were unaffected by NaCl stress, the tiller number, plant height, and shoot and root dry weights decreased with increasing salt concentration, in the order of Na2CO3＞NaHCO3＞NaCl. In addition, propagation mechanisms higher concentrations of Na+ accumulated in the shoots and roots of oat seedlings under Na2CO3 stress and NaHCO3 stress than in seedlings under NaCl stress. Reductions in concentrations of K+ were also greater under both Na2CO3 and NaHCO3 stress than NaCl, especially in the roots. Large amounts of Cl－ and proline were found to accumulate in oat seedlings, most likely as a strategy for maintaining osmotic and ionic homeostasis under NaCl stress
Effect of mycorrhization on growth and physiology performance of Quercus species
Get PDFThe development of mycorrhiza could contribute to strengthening the resilience of forest ecosystems to climate change. Several mycorrhizal fungi are known for their valuable effect in increasing plant performances and adaptation to stressful environmental conditions. Thereby, this research aims to investigate how Terfezia boudieri (Chatin) mycorrhizal fungi affects the growth (primary root length, above-ground plant weight) and the physiological behaviour (net photosynthesis, responses to intercellular [CO2] and the intensity of photosyntically active radiation) of Quercus subsp. coccifera and Q. suber L. Inoculated and non-inoculated seedlings of the two Quercus species were grown in one-liter pots in the greenhouse, with a temperature that ranged from 25 to 30 °C, natural lighting and an irrigation applied twice a week with top water. Results revealed that primary root length and the above-ground biomass increased with mycorrhization. In addition, mycorrhization promoted net photosynthesis (at 400 ppm and at saturation point), the apparent quantum yield, the water use efficiency, and the photosynthetic pigments contents. However, inoculation decreased the light compensation point for both species. Effectiveness of T. boudieri inoculation on Quercus sp. performance, highlights the potential of the mycorrhization process to improve forest management and resilience to climate change
Increasing rainwater use efficiency, gross return, and grain protein of rain-fed maize under nitrate and urea nitrogen forms
Get PDFThe soil's capability to adjust and mitigate the effects of water shortage due to climate change is limited in some regions such those that suffer from the low rainfall rates. This experimental field study aimed to assess the effects of two inorganic nitrogen forms on maize performance (i.e., growth, yield, grain protein content, and gross returns) and rainwater use efficiency (RUE). Treatments comprised three replicates of synthetic nitrogen forms (i.e., urea and nitrate) that were located in the main plots with four levels that were assigned to the subplots (i.e., 0, 25, 50, and 100 kg N ha-1). Nitrate application resulted in a higher plant height (62 cm) at the vegetative phase with superior values (11.6%) recorded in grain protein than those obtained from other treatments. In addition, the highest grain yield was obtained in nitrate-treated plots in comparison to other N application forms. The leaf area index registered optimal values when 50 kg N ha-1 was applied. On the application of two nitrogen forms, nitrate resulted in a higher RUE (2.1-3.4 kg ha-1 mm-1) than that obtained from maize treated with urea (1.3-1.9 kg ha-1 mm-1). This translated to a 123-234% increase in RUE over the control (N0), which is the key smallholder farmers’ practice. It is recommended that producing maize using nitrate nitrogen at 50 kg N ha-1 as opposed to urea can increase yield stability, and rain use efficiency with higher gross returns in water-scarce agro-ecologies in SSA
Molecular characterization of guava Psidium guajava in Cereté, Córdoba, Colombia
Get PDFGuava (Psidium guajava L.) is the most cherished cultivated fruit species in the Myrtaceae family, and it is a perennial tree native to tropical America. The objective of this study was to determine the genetic variability of Psidium guajava in Cereté (Colombia) using SSR markers. DNA extraction was performed using the Mini-prep method with modifications. Nine microsatellites were amplified using the PCR Touchdown technique. Genetic-population parameters such as the number of alleles, effective number of alleles, observed heterozygosity, expected heterozygosity, fixation index, Hardy-Weinberg equilibrium, and polymorphic information content were calculated using PopGene 1.31 software. The number of alleles varied between 4 for markers mPgCIR13, mPgCIR20, mPgCIR23, and 8 for marker mPgCIR19, respectively. The average value of effective number of alleles was 3.722, observed heterozygosity was 0.217, and expected heterozygosity was 0.254. The average fixation index was 0.101. Hardy-Weinberg equilibrium tests revealed significant differences in the markers. The FIS coefficient had an average value of 0.385, the FIT coefficient showed an average of 0.490, and the FST coefficient had a value of 0.178. Genetic distance analysis showed that Mateo Gómez was closely related to Retiro de los Indios, while Rabolargo appeared to be the most distant population. The study revealed low genetic variability within and between the populations studied, possibly, reflecting the type of asexual propagation applied in guava crops
Biochemical responses of Silybum marianum seedlings to independent and combined salt and SiO2 treatments
Get PDFIn recent years, silicon dioxide (SiO2) particles have drawn increasing attention due to their potential to enhance plant tolerance to various stresses by modulating physiological and biochemical processes. Salinity is an important abiotic stress with a harmful impact on crop growth and productivity. In this context, the aim of this study was to investigate the influence of silicon dioxide (SiO2) addition on milk thistle (Silybum marianum (L.) Gaertn.) under salinity stress. Thus, individual and combined effects of the application of sodium chloride (NaCl, 50 and 100 mM) and SiO2 particles (0.1 mM) on some physiological and oxidative stress parameters, such as growth variables, photosynthetic pigments and soluble protein contents, the levels of an oxidative stress biomarker (malondialdehyde), and the specific activity of several antioxidant enzymes (superoxide dismutase, catalase and peroxidase) were evaluated. The results revealed that salt stress (100 mM) inhibited plant growth and decreased chlorophyll and carotenoid levels, whereas the added SiO2 partially mitigated these negative effects. In addition, the 100 mM NaCl treatment significantly increased peroxidise (POD) activity and decreased soluble protein content after 22 days, while no significant differences were found for group subjected to salt stress in the presence of SiO2. Results suggest that application of SiO2 on salt-stressed milk thistle may modify the seedling metabolism and increase the plant salt tolerance capacity
Investigations on the chemical composition of volatile oils extracted from the leaves of spontaneous and cultivated Taxus baccata L. trees
Get PDFTaxus L. is accepted in the literature as natural resources of biologically active compounds and volatile oils, with applications in medicine, pharmaceuticals, food, cosmetics, and with ecological impact on the natural living environment. In this context, the present work aims to analyze by GS/MS techniques the chemical composition of volatile oil obtained by hydrodistillation of leaves harvested from spontaneous and cultivated female individuals of Taxus (dried and fresh plant material) and to spectrophotometrically evaluate the hydrosols resulting from their hydrodistillation. The compounds with the highest concentrations in the volatile oil obtained from the spontaneous taxon Taxus baccata L. were hexahydrofarnesyl acetone (33.03% fresh leaves; 20.09% dried leaves); ar-abietatriene (14.98% dried leaves; 3.03% fresh leaves); phthalic acid, hex-3-yl isobutyl ester (10.51% dried leaves); salicylic acid, benzyl ester (8.11% dried leaves). In the cultivated taxon Taxus baccata the compounds identified with the highest concentrations were 1-octen-3-ol (25.61% fresh leaves); phytol (12.50% dry leaves); geranyl acetone (11.90% dry leaves); manoyl oxide (11.85% dry leaves; 10.86% fresh leaves); 1,9-decadence (7.92% fresh leaves). The compounds with the highest concentrations in the oil extracted from the leaves of Taxus baccata ‘Robusta’ were hexahydrofarnesyl acetone (17.81% fresh leaves); pentacosane (11.28% dry leaves); heptacosane (11.27% fresh leaves); tetracosane (11.13% dry leaves); tricosane (8.45% fresh leaves). The chemical composition of volatile oils from yew is influenced by many exogenous factors such as soil, light, and endogenous factors such as age, DNA
Comparative study on the antimicrobial activity of propolis, catechin, quercetin and gallic acid
Get PDFPropolis, considered one of the most effective natural broad-spectrum antibiotics, which do not induce resistance or destroy the organism’s commensal flora, together with catechin, quercetin and gallic acid (at different concentrations), have been tested against Gram positive bacteria Streptococcus pyogenes ATTC 19615, Stapylococcus aureus ATCC 25923 and Gram negative Escherichia coli ATCC 25922 Pseudomonas aeruginosa ATCC 27853, Salmonella enterica ATCC 14028, Shigella flexneri ATTC 12022, as well as the yeast Candida albicans ATTC 10231, using the agar diffusion method. Propolis and the three compounds showed antimicrobial potential at most concentrations. The highest sensitivity to propolis (conc. 0.001-1%) was shown by the Gram-positive bacterial strain S. pyogenes, followed by the Gram-negative bacterium Escherichia coli, while the other species had an equal and reduced reaction. Gallic acid showed high antibacterial activity on S. aureus, P. aeruginosa and S. enterica, and a reduced effect on other bacterial strains. The antibacterial efficiency of 3.0224% quercetin was high against the bacterium S. pyogenes and catechin (2.9028%) proved to be the best antifungal, followed by propolis 1%, and quercetin 3.0224%. At certain concentrations, propolis and the three compounds could supplement gentamicin and ampicillin, as they have shown similar or even higher antibacterial efficacy than conventional drugs
Climate change, its impact on crop production, challenges, and possible solutions
Get PDFClimate change poses serious threats to agriculture and food security, and extreme weather events have reduced crop productivity worldwide. Future projections predict that the average global temperature will rise by 2.0 to 6.4 °C and the increase in sea level will be 59 cm by the end of 21st century. The unprecedented rise in temperature has led to an increase in the incidence of heat waves, droughts, floods, and irregular patterns of precipitation. These changes have a dramatic impact on prevailing agricultural cropping systems, productivity, and food security of people regionally and globally. The change in climatic parameters have substantial effects on weeds, diseases, insect, and pests in different ways, and can result in an increase of their geographical distribution, number of generations, and survival during winter. Thus, to sustain the crop production on the eve of climate change is the main challenge. Therefore, adaptation measures are prerequisites to reduce the effects of climatic changes on production of agricultural crops. In this review, a brief insight has been given in the impact of climate change on agriculture and, the future challenges of climate change on the production of crops. In addition, integrated approaches, or recent developments for the improvement of crops such as breeding, transgenic approaches to biotechnology, and functional genomics, agronomic practices, cultivation of climate resilient crops, and nanotechnology for abiotic stress such as drought stress, temperature, heat, and salinity tolerance have also been discussed
Leaf disease caused by Epicoccum thailandicum on Amomum villosum in China
Get PDFAmomum villosum is widely planted as a cash crop and medicinal plant. Recent reports of leaf diseases that result in yield reduction of Amomum villosum fruits raise concerns, which may play an important role in yield losses. Understanding the aetiology of current and new diseases of Amomum villosum is important to address production issues and to formulate effective disease control measures. An organizational separation method was used to isolate phytopathogen from leaves. Ten fungi were isolated from the diseased leaves. Among the selected microorganisms, fungi AP5 showed typical pathogenic symptoms and fulfilling Koch’s requirements. The rDNA internal transcribed spacer region (ITS) with primers ITS1/ITS4, 28S ribosomal RNA gene (LSU) with primers NL1/NL4, RNA polymerase II second largest subunit (RPB II) with primers fRPB2-5f/fRPB2-7cR, and beta-tubulin (tub2) with primers BT2a/BT2b of pathogenic strain were amplified and sequenced. AP5 was identified as Epicoccum thailandicum based on morphological and phylogenetic analyses. This is the first report that Epicoccum thailandicum is the pathogenic fungi infecting Amomum villosum leaves