Articles

The calyces of Hibiscus sabdariffa have been used by many communities as herbal tea. Their anthocyanin contents have been reported as the key component in anti-obesity studies. This present work reported results of anthocyanin content of calyces in two varieties of H. sabdariffa collected from Sabak Bernam, Selangor, Malaysia. The samples have been authenticated in the Herbarium, Institute of Bioscience, University Putra Malaysia prior to the study. The samples were processed and the ground dry raw material and its aqueous extract were analyzed using Fourier Transform Infrared (FTIR) and Two-Dimensional Infrared (2DIR). The short hybrid calyces (FT11-15A) raw material spectrum showed more than 80% similarity with long wild variety calyces (FT11-15B) when using “Compare” in analysis. The differences of both samples were obviously shown in their aqueous extract spectra. The peak at 1672 cm-1 and 841 cm-1 showed that tri-substituted double bond in FT11-15B aqueous extract was not present in FT11-15A aqueous extract spectra, whereby a double peak was assigned at 1221 cm-1 referred to anti symmetry stretching of aromatic and vinyl =C-O-C- with other =C-O- and 1192 cm-1 is assigned In-plane δ C-H in FT11-15A aqueous extract. The peak at 1071 cm-1 assigned as bonding C-H in plane bending of phenyl of both samples was the only peak comparable with standard delphinidin and cyanidin which are used for qualification and quantification of sample content. Aqueous extract spectra of both samples showed higher number of peaks detected compared with raw material spectra, which was attributed to the higher solubility of anthocyanins in water. The 2DIR correlation spectroscopy is advantageous in enhancing the qualitative analysis of herbal products. The anthocyanin content in both varieties of H. sabdariffa in descending amount is delphinidin-3-O-sambubioside (DS), cyanidin-3-O-sambubioside (CS), delphenidin-3-O-glucoside (DG) and lastly cyanidin-3-O-glucoside (CG). FT11-15A has more content of DS and DG of raw material and CG of water extract plus TFA than FT11-15B, whereby, FT11-15B has more content of CS, CG of raw material and DS, DG, CS of water extract plus TFA than FT11-15A.

Pumpkins (Cucurbita pepo) are grown all around the world for a variety of reasons ranging from agricultural purposes to commercial and ornamental sales. The pathogens causing the rot of pumpkin in the world include fungi, bacteria, and viruses. The study was aim to identify fungal pathogens of pumpkin rot during storage, as well as control measures of the diseases using wood ash, mango leaf and rice chaff. Three hundred and sixty-six (366) fruits of pumpkins were studied in Pela, Gaya and Kulinyi districts of Hong Local Government Area of Adamawa State. The diseased samples (fruits) were randomly purchased. Of all the districts visited, Kulinyi has the highest percentage of disease samples (43.82%) while the least is Gaya district with 21.35%. Potato Dextrose Agar (PDA) was used for the isolation of pathogens and these gave Fusarium solani, Aspergillus niger, Aspergillus flavus, and Phytophthora capsici. All the fungal isolates exhibited different degree of pathogenic effect on the pumpkin fruits. The pathogens are susceptible to treatment both In-vitro and In-vivo control trials with wood ash and mango leaf at p ≤ 0.05. Inhibition improved with increased in concentration of the wood ash and mango leaf. Rice chaff treatment equally proved worthwhile with significant inhibition compared to the control at p ≤ 0.05.

The circadian clock is an endogenous molecular oscillator with a period of about 24 hours, which regulates the physiology and developmental processes of almost all higher plants. Pseudo-response regulators (PRRs) are an important part of the central clock oscillator, together with other clock genes, constituting interlinked transcriptional feedback loops, which partly influence plant growth and development. In this study, a circadian clock-related gene MsPRR7 was cloned from Medicago sativa (alfalfa) by homologous cloning. The full length MsPRR7 gene was 2648 bp in length, with an open reading frame of 2385 bp encoding a protein of 795amino acids. Phylogenetic analysis showed that the MsPRR7 was closely related to PRR7 from the PRR family of Arabidopsis thaliana. Subcellular localization analysis found that MsPRR7 was located in the nucleus. Quantitative reverse-transcription polymerase chain reactions (qRT-PCR) demonstrated that expression of MsPRR7 gene transcripts in leaves was affected by circadian rhythms, and that its expression level increased with an extension of illumination time, reaching a peak around 8–10 hours. These results will provide the experimental basis for further study of the regulation of PRR family genes in alfalfa.

Peaches, Prunus persica were planted as grafted saplings in an avocado orchard previously infested with Armillaria mellea (Vahl) P.Kumm. Trees were planted in large or small holes with or without fresh yardwaste chips added as an amendment and with or without a Trichoderma biocontrol product sprayed into the hole. Trees were monitored for six years -- growth and mortality was tabulated. Six years later 40% of the trees had died from the disease. Trees planted in a large hole were more likely to survive than in a smaller hole (P=0.07) and trees in large holes with fresh organic matter added were the most likely to survive (P=0.04). Trichoderma sprays in the planting hole did not increase survival rates. While growth was initially retarded by adding fresh yardwaste to the hole, in later years none of the treatments affected growth rates.

Although laurel wilt disease was first reported in the United States in 2002 from redbay trees (Persea borbonia) around Savannah, Georgia it has rapidly spread throughout the southeastern coastal plain including Georgia and Florida. In the current study, transects were used to assess the spread and impact of the disease on two native bay trees redbay (P. borbonia) and swampbay (P. palustris) from north Florida in a semi-naturalized ecological preserve. Although tree size and mortality rates have been reported previously, this study provides the first size-based static life tables for both species. While a significantly higher percent (76%) of swampbay trees exhibited signs of laurel wilt disease compared to redbay trees (62%); redbay had more of its canopy damaged by the disease (41% vs. 32% for redbay vs. swampbay respectively); this resulted in a significantly smaller stem diameter for P. borbonia compared to swampbay, both species are experiencing significant declines due to the disease. Both species exhibited a Type III survivorship curve in which the vast majority of individuals were in the smallest size class (average stem diameter was only 2.5 and 3.6 cm for redbay and swampbay respectively). Although traditionally, population age (or size) structure that is heavily biased toward younger or smaller size classes suggests that the population is likely to expand in the future, for these bay trees high mortality rate due to beetle/fungal infestation of larger size classes is responsible for this trend; the smallest size classes are largely free from beetle infestation and laurel wilt disease because the stem diameter is likely insufficient to support beetle development. Results from this study suggest that swampbay is also highly susceptible to laurel wilt disease and its populations are likely to exhibit a similar (albeit slower) decline in Florida’s wetland and mesic ecosystems.

Tropical forests have long been of interest to biologists because of their high species diversity and their complicated patterns of community organization. The recent ecological studies which have demonstrated that tropical trees are diverse in their reproductive biology and dynamic population structure. Asynchronous flowering among the clones in a clonal seed orchard is an inherent problem resulting in poor seed and fruit set in them. These results in the complete defeat of the prime objective of establishment of clonal seed orchards (CSOs) i.e. abundant quality seed production poor flowering and asynchronous flowering between the clones are a major bottleneck in higher seed set in these clonal seed orchards across the country. Asynchrony found between clones may be attributed to the origin of clones, which are collected from different zonal populations as revealed by isoenzyme and DNA markers studies. This article reviews the work done in CSOs across the world and suggests an alternate strategy in designing the clonal seed orchards of the future.

Stable reference genes are indispensable for ensuring the fidelity of determined gene expression levels. However, the expression levels of reference genes are unable to remain constant under all possible experimental conditions. Therefore, the stability determination of reference genes is necessary in an experimental system set. In the preset study, the stability of nine cucumber candidate reference genes (CsACT, CsUBQ, CsEF1α, CsCYP, CsαTU, CsCACS, CsTIP41, CsYSL8 and CsHEL) subjected to stresses from Phytophthora melonis(P. melonis) were determined using four different analysis methods, including Delta Ct, BestKeeper, NormFinder and GeNorm. The study results revealed that CsUBQ and CsCYP were the most stable genes suitable as internal control in cucumber plants under attack by P. melonis condition.

The use of novel PGPR as bio inoculant is an alternative sustainable agricultural practice to improve soil health, grain quality, increase crop productivity, and conserve biodiversity. The aim of this study is to isolate, and characterized PGP bacteria colonizing tef rhizosphere during the seedling stage. For this concern, 426 samples of tef (Eragrostis tef) rhizosphere soils and roots were collected from East Shewa zone, Oromia regional state. 200 morphologically different bacterial pure colonies were isolated and screened for their PGP traits and biocontrol properties. Among these 40.5% isolates were positive for phosphate solubilization. 36% were positive for IAA production, 4.5% were positive for ammonia production, 19 % were positive for (EXPS), 15.5% were positive for protease production, 12.5% were positive for HCN productions, 9.5 % were positive for cellulase production, 4% were positive for amylase production, 3.5% were positive for chitinase production. For abiotic stress tolerance test, all of the isolates were grown well at 20oc and 30oc and neutral pH, 27% isolates were grown well at 4oc, 25.5% grew at 40oc, 25.5% were grown well on pH-9 and pH-11, 23.5% were tolerated pH-5, 3.5% grew at 50oc and 60oc, 13.5% were grown well on 5% NaCl (w/v), 3.5% were grown well on 10 and 15% NaCl (w/v), which indicated these isolates can survive in some extreme conditions. Totally 15 bacterial species having PGP traits, biocontrol properties, and abiotic stress tolerance ability were identified using the Biolog bacterial identification system. Among these, the majority of the identified PGPR have utilized carbohydrate, carboxylic acid, and amino acid, which are the main components of plant root exudates. The above results indicated that thus PGPR can be used as biofertilizers as well as biocontrol agents to replace agrochemicals to improve crop productivity. Hence, these species can be further formulated and used for greenhouse and field applications.

Ilex paraguariensis, also known as ‘Yerba mate’, occurs naturally in Argentina, Brazil and Paraguay and is also grown in these countries with different intensities. Leaves and branches of this plant are used in the preparation of a stimulant beverage that beside social importance has notorious health impact. However, the cultivated herbs present low productivity, due to deficiencies in cultivation and harvesting techniques, as well as due to the abiotic stresses that this species is subject to. The discovery and characterization of cold response mechanisms in plants such as Arabidopsis thaliana, began research in order to unravel the physiological and molecular mechanisms in response to cold in other plant species. In this work, we studied the physiological response observed in Ilex paraguariensis plants submitted to low temperatures (0°C), with or without a pre-moderate acclimatization treatment period of (8°C). Our results suggest the existence of an acclimation response in Ilex paraguariensis, similar to that described in other species of the same temperature.

The age-old battle between plants and viruses has many twists and turns. Plants acquired the RNAi factors to checkmate the viruses and the viruses encode VSRs to defeat RNAi for their own survival. Plants designed mechanisms to neutralize the toxic effects of VSRs and the viruses, in their turn, use host microRNAs to strengthen their infection processes. The infightings between these two entities will take different shapes with prolonged evolution and accordingly the researchers will dig these novel forms of duels not only to throw lights in the involved mechanisms but also to manipulate various antiviral strategies. Some of the research courses that might come up in the immediate future are discussed.