Phosphate solubilizing bacteria promote growth and enhance nutrient uptake by wheat

Phosphorus (P) fixation limits availability of P to plants in tropical soil, which is a major constraint for crop production. The aim of our research was to isolate, screen and characterize phosphate solubilizing bacteria (PSB) from wheat and evaluate their efficacy in P nutrition in wheat. Upon screening, 9 isolates showing varying level of phosphate solubilizing activity in both agar plate and broth assays using Pikovskaya’s medium were obtained. The pH of the culture media was decreased with increased bacterial growth suggesting that they might secrete organic acids to solubilize insoluble phosphorus. In vitro wheat seedling bioassay with two superior PSB isolates (PSB1 and PSB8) and varying sources of P revealed that both isolates significantly enhanced seedling growth (shoot and root length, shoot and root dry weight) and nutrient contents (%N, %P and %K) in plant tissue compared to control (no PSB). The performance of PSB8 was superior to PSB1 in respect of all the parameters studied. The PSB8 was tentatively identified as Pseudomonas sp. through 16S rRNA gene sequencing. Our results suggest that Pseudomonas sp. PSB8 isolated from wheat might be useful for improving P nutrition in wheat in soils with low available P

Chemical composition of the essential oil of Ocimum tenuiflorum L. (Krishna Tulsi) from North West Karnataka, India

The chemical composition of the essential oil of flowering aerial parts of Ocimum tenuiflorum L. growing in the North West Karnataka, India, was investigated. The hydro-distilled essential oil was analyzed by gas chromatography equipped with flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC/MS). Results demonstrated that the oil was found to be rich in phenyl derivative compounds (83.8%). The major compound was identified as methyl eugenol (82.9%) among twenty-six compounds, comprising 98.9% of the total oil

Functional properties of Okra Abelmoschus esculentus L. (Moench): traditional claims and scientific evidences

Okra, Abelmoschus esculentus L. (Moench) is an important vegetable crop cultivated in tropical, subtropical and warm temperate regions around the world. Besides the nutritional benefit, the different parts of the plant are used extensively in traditional medicine (antidiabetic, antipyretic, diuretic, antispasmodic, etc) around the world. This review critically assesses the nutritional values, phytochemistry, preclinical pharmacological properties and the possible future application of the okra. Effort is made to correlate the traditional claims in the context of experimental evidences

Therapeutic effect of Ananus comosus peel on 7, 12 dimethylbenz(a)anthracene induced breast cancer in female wistar albino rats

Ananus comosus, has demonstrated a wide variety of biological activities which make it a good plant source for the treatment of many oxidative stress mediated diseases. The present study was aimed to evaluate therapeutic potential by assaying the activities of liver marker and lysosomal enzymes in 7, 12 dimethylbenz(?)anthracene induced mammary cancer bearing rats. Animals were divided into five groups of six numbers each. Group 1 served as control, group 2 induced mammary carcinogenesis, group 3 and 4 were treated with plant extract and tamoxifen and group 5 served as animals treated with plant extract alone. All the animals were sacrificed after 30 days treatment, serum and mammary tissue are used for the analysis of liver marker and lysosomal marker enzymes using standard protocols. The rats were induced with mammary cancer by DMBA showed altered the levels of liver markers and lysosomal marker enzymes in serum and mammary tissue. On the other hand, oral administrations of ethanolic extract of Ananus comosus peel and standard drug tamoxifen to mammary cancer bearing rats for 30 days, those levels were brought back to near normal. The histology of mammary tissues inevitably supports the biochemical alterations and this was attributed due to the interaction of Ananus comosus peel through the induction or inhibition of metabolism and also the modulating property in the marker and lysosomal enzymes

Plant-derived natural products as leads to antitumor drugs

Cancer is the main cause of death worldwide. Chemotherapeutic agents used for disease treatments have shown limited antitumor activity, with a high recurrence rate. It has prompted the research efforts to identify anti-tumor compounds. Research on medicinal plants began to focus on discovery of natural products as potential leads to antitumor drugs. Medicinal plants are very interesting, have the ability to produce remarkable chemical structures with diverse biological activities. Plant-derived natural products have been used by human societies for millennia, and their biological source is most likely available and can be employed for production, have been considered as valuable sources for antitumor drugs. Many interesting natural products with biological activity are evidenced in the past few years. This review highlights the potential of natural compounds as candidates for antitumor drugs. A brief illustration of the sources and general biological effects of the main classes of plant-derived natural compounds and related molecules are also provided

Germplasm and conservation of rare and endangered tree species endemic to east China

There are plenty of native tree species in east China, including 16 rare and endangered tree species belonging to 11 genera in 10 families. Because of narrow distribution area, weak qualitative competitiveness and reduced natural regeneration, the number of these tree species are decreasing substantially. Thus, it is necessary to protect endangered species endemic to the region. In this paper the basic data on germplasm, geographical distribution, biological characters, endangered status and current conservation strategies of rare and endangered species endemic to east China are presented. The gap areas were identified and accordingly implications were made on the future work on the native rare and endangered tree species in east China should focus on the basic research of conservation biology, establishment of the information system, solution of problems in reproductive biology and more emphasis on the key regions for protecting biodiversity

Maximum quantum yield of photosystem II to assist in the measurement of herbicide selectivity in popcorn

The objective of this study was to evaluate the selectivity/phytotoxicity of herbicides (mesotrione, nicosulfuron, and tembotrione) using the maximum quantum yield of photosystem II associated with biometric analyses. The experiment was conducted using three popcorn genotypes (BRS Angela, IAC-125 and UENF-14) and three herbicides (mesotrione, tembotrione and nicosulfuron, and a control treatment “WITH WEEDING?”. The quantum yield of photosystem II was obtained through a modulated light portable fluorometer MINI-PAM, from the chlorophyll a fluorescence. Regarding the biometric analyses, the following characteristics were evaluated: a) number medium of ears of the corn, b) grain yield in kg ha-1, c) average weight of 100 grains, and d) popping expansion. The genotypes were sensitive to tembotrione with higher intensity for the IAC - 125. The maximum quantum yield of photosystem II showed useful tool for studies of selectivity / phytotoxicity symptoms of herbicides used

Past, present and future of rice blast management

Blast disease caused by fungal pathogen Magnaporthe oryzae is the most severe disease of rice (Oryza sativa L). On an estimate it annually destroys rice, which can feed around 60 million people. Keeping in view of the importance of the disease, various management strategies like controlled use of nitrogen fertilizers, application of silica and flooding of paddy fields are the practices in use to reduce the rice blast since long time. Improved chemical methods include utilization of copper fungicides, organomercuric and organophosphorus compounds. Some antibiotics e.g., Blasticidin S and Kasugamycin and many systemic and site specific fungicides including melanin biosynthesis inhibitors and plant activators were also utilized effectively for blast management. In the recent years leaf extracts of tulsi and bael have been found effective. Due to the highly variable nature of M. oryzae, exploitation of durable host resistance has remained a challenging job for plant pathologists and breeders. Lots of efforts have been made worldwide to study the variability in the pathogen and to find out the resistance sources. To date approximately 100 R genes for blast resistance have been mapped and 20 of these genes have been cloned in rice. Now, scientists are looking forward to develop durable resistant varieties through pyramiding of quantitative trait loci and major genes. Among the biocontrol agents, different strains of Bacillus spp. and Streptomyces sindeneusis are in use. The availability of rice and M. oryzae genome sequence data are facilitating blast resistance management program to new paradigms which includes isolation and characterization of R and Avr genes, development of noble fungicides, transformed bioagents, transgenic rice and durable resistance

DNA polymerase ? - a novel DNA repair enzyme in higher plant genome

DNA polymerase lambda (Pol ?) is a novel family X DNA polymerase which has been shown to play key role in nuclear DNA repair and meiotic recombination. Recent studies in mammals support function of this enzyme in base excision repair in response to oxidative DNA damage. However, in plants the biological function of Pol ? in oxidative stress response is still largely unknown. This review will survey recent advances in our understanding of role of Pol ? in repair of oxidative DNA damages and its possible potential involvement in plant’s base excision repair (BER) pathway in response to oxidative stress