Plant-based Techniques Research Articles

Plant-based vaccines against viral hepatitis: A panoptic review.

The traditional vaccines against hepatitis have been instrumental in reducing the incidence of some types of viral hepatitis; however, the need for cost-effective, easily distributable, and needle-free vaccine alternatives has led to the exploration of plant-based vaccines. Plant-based techniques offer a promising avenue for producing viral hepatitis vaccines due to their low-cost cultivation, scalability, and the potential for oral administration. This review highlights the successful expression of hepatitis B surface antigens in plants and the subsequent formation of virus-like particles, which have shown immunogenicity in preclinical and clinical trials. The challenges such as achieving sufficient antigen expression levels, ensuring consistent dosing, and navigating regulatory frameworks, are addressed. The review considers the potential of plant-based vaccines to meet the demands of rapid vaccine deployment in response to outbreaks and their role in global immunization strategies, particularly in resource-limited settings. This review underscores the significant strides made in plant molecular farming and the potential of plant-based vaccines to complement existing immunization methods against viral hepatitis.

Indoor Air Pollution: A Review on the Challenges in Third World Countries

Background: The challenges of third-world countries toward curbing indoor air pollution seem insurmountable as its solution is closely linked to their economic incapacities, lifestyle, and existing outdoor air quality. The economic incapacities include types of the cookstove, fuel sources, types of insecticides and pesticides, building patterns, indoor fermentation activities (such as leaving dirty plates and biological waste in the house for a long time), and regulation on the use of deodorants. Aside from the common pollutants from these sources, the reactive chemistry of pollutants leads to other kinds of pollutants which have been reported to be short-lived but dangerous. Objectives: The objectives of the study are to: profile emerging indoor pollutants; examine the pollutant dynamics and their impact on unplanned regions of developing countries; offer solutions to curb indoor pollution in the identified region; elaborate on the cost analysis of existing solutions and how irrelevant they may be due to the rising poverty index; and project how government policies could help in reducing indoor pollution. Design: This paper is a review that wholistically examined indoor pollution. A total of fifty-six articles was reviewed in addition to the data obtained from MERRA-2. Results: The study observed that indoor air pollution dynamics are more complex—compared to outdoor air pollution. It was observed that the possibility to control indoor air pollution is based on the type of pollutants, the reactive chemistry of the pollutants, and ventilation in the building. This review shows that poverty is one of the many reasons why indoor air pollution would be a source of menace for a long time in third-world countries. Several solutions to curbing indoor air pollution were considered with a principal focus on cost and availability. Limitations: Most experimental results that were used to corroborate postulates were obtained from the literature. The accuracy of those experiments and the sensitivity of the equipment used cannot be verified. Conclusion: The plant-based technique was identified as a perfect solution to indoor air pollution control in third-world countries but the local architecture and lifestyle of most third-world countries constitute a threat to its adoption. It was observed that less than 8% of third-world countries have specific Air Quality Acts which have not been amended for decades. Most third-world countries have a general Environmental Act with air quality as a sub-section in the Act with very low fines for violators. The inclusion of indoor air quality as a vital public health issue in third-world countries is necessary for the preservation of lives and posterity.

INSECTICIDAL PROPERTY OF TERPENES AGAINST MAIZE WEEVIL, SITOPHILUS ZEAMAIS (MOTSCHULSKY)

Synthetic pesticides are used indiscriminately in insect pest management, which damages the ozone layer and causes resistance in target organisms as well as neurotoxicity, carcinogenicity, teratogenicity and mutagenesis in non-target organisms. Due to these negative consequences, research is now focused on using plant-based techniques to control insect pests. The maize weevil, Sitophilus zeamais (Coleoptera: Curculionidae), was tested in the laboratory to determine the insecticidal effects of two pure essential oil constituents, namely α-pinene and β-caryophyllene. These two terpenes were tested against S. zeamais for their toxic, ovipositional, developmental, and feeding inhibitory effects. When S. zeamais adults were fumigated for 24 and 48hrs, the median lethal concentrations (LC50) of α-pinene and β-caryophyllene were 0.412 and 0.305 μlcm-3 and 0.486 and 0.315 μlcm-3 air respectively. When S. zeamais adults were exposed for 24 and 48hrs in a contact toxicity assay, the LC50 values for α-pinene and β-caryophyllene were 0.388 and 0.256 μlcm-2 and 0.308 and 0.216 μlcm-2 area respectively. Adults exposed to sub-lethal concentrations of both terpenes experienced decreased acetylcholine esterase (AChE) enzyme activity. In S. zeamais, α-pinene and β-caryophyllene decreased oviposition, progeny output and eating. According to this study, α-pinene and β-caryophyllene can be used to make environmentally acceptable formulations and as a substitute for synthetic insecticides.

A review on phyto-remediation by aquatic macrophytes: A natural promising tool for sustainable management of ecosystem

Heavy metal pollution is a significant source of pollution in the environment. Heavy metal contamination in aquifers endangers public health and the freshwater and marine ecosystems. Traditional wastewater treatment methods are mainly expensive, ecologically damaging, ineffective, and take much time. Phyto-remediation is a plant-based technique that gained popularity by discovering heavy metal accumulating plants that can accumulate, transport, and consolidate enormous quantities of certain hazardous contaminants. This is a low-cost sustainable evolving technique featuring long-term utility. Several terrestrial and aquatic vegetation have now been examined for their ability to repair polluted soils and streams. Several submerged plants have already been discovered to remove harmful pollutants such as Zn, As, Cu, Cd, Cr, Pb & Hg. The most important part of effective phyto-remediation is selecting and choosing effective plant species. Aquatic macrophytes have high effectiveness for removing chemical contaminates. Watercress, hydrilla, alligator weed, pennywort, duckweed plants, water hyacinth are examples of aquatic macrophytes. Several macrophytes' metal absorption capability and procedures have now been explored or analyzed. Most of these research demonstrated that macrophytes had bioremediation capability. The bioremediation capability of macrophytes can be increased even more by employing novel bioremediation techniques. To demonstrate the extensive application of phyto-remediation, a comprehensive summary assessment of the usage of macrophytes for phyto-remediation is compiled.

Increase in Phytoextraction Potential by Genome Editing and Transformation: A Review.

Soil metal contamination associated with productive activities is a global issue. Metals are not biodegradable and tend to accumulate in soils, posing potential risks to surrounding ecosystems and human health. Plant-based techniques (phytotechnologies) for the in situ remediation of metal-polluted soils have been developed, but these have some limitations. Phytotechnologies are a group of technologies that take advantage of the ability of certain plants to remediate soil, water, and air resources to rehabilitate ecosystem services in managed landscapes. Regarding soil metal pollution, the main objectives are in situ stabilization (phytostabilization) and the removal of contaminants (phytoextraction). Genetic engineering strategies such as gene editing, stacking genes, and transformation, among others, may improve the phytoextraction potential of plants by enhancing their ability to accumulate and tolerate metals and metalloids. This review discusses proven strategies to enhance phytoextraction efficiency and future perspectives on phytotechnologies.

Antibacterial Potential of Zinc Oxide Nanoparticles Synthesized using Aloe vera (L.) Burm.f.: A Green Approach to Combat Drug Resistance

Microbial infections and antibiotic resistance are some of the prime factors that are ascribed to endanger human health. Several reports have highlighted that drug-resistant pathogens assist in the etiology of various chronic diseases and lead to fatality. The present study deciphered the role of zinc oxide nanoparticles (ZnO NPs) as therapeutics against selected bacterial strains. The plant-based technique was followed to synthesize ZnO NPs. The synthesis was confirmed with different techniques viz. X-ray diffraction, transmission electron microscope (interplanar spacing at 0.126 nm), scanning electron microscope (flower-like structure), and Fourier transform infrared spectroscopy. The antibacterial analysis revealed that ZnO NPs inhibited the growth of all tested strains (Escherichia coli, Staphylococcus aureus, Salmonella typhi, Bacillus subtilis, and Klebsiella pneumoniae) to a greater extent (MIC ranged between 0.013±0.004-0.0625±0 mg/mL) as compared with ZnO compound (Bulk material). In the present study, ZnO NPs were produced in a cost-effective and environmentally sustainable way using a green process and can be used as a remedy for drug-resistant pathogens.

Evaluation of the Anticancer Activity of Phytomolecules Conjugated Gold Nanoparticles Synthesized by Aqueous Extracts of Zingiber officinale (Ginger) and Nigella sativa L. Seeds (Black Cumin).

The conventional physical and chemical synthetic methods for the preparation of metal nanoparticles have disadvantages as they use expensive equipment and hazardous chemicals which limit their applications for biomedical purposes, and are not environment friendly. However, for the synthesis of biocompatible nanomaterials, plant-based techniques are eco-friendly and easy to handle. Herein a simple, single-step biosynthesis of gold nanoparticles using aqueous extracts of Nigella sativa (NSE) and Zingiber officinale (GE) as a reducing and capping agent has been demonstrated. The formation of gold nanoparticles (Au NPs) was confirmed by X-ray diffraction, UV-Vis, and EDS spectroscopies. Spectroscopic and chromatographic analysis of GE and NSE revealed the presence of bioactive phytochemical constituents, such as gingerol, thymoquinone, etc., which successfully conjugated the surface of resulting Au NPs. TEM analysis indicated the formation of smaller-sized, less-aggregated, spherical-shaped Au NPs both in the case of GE (~9 nm) and NSE (~11 nm). To study the effect of the concentration of the extracts on the quality of resulting NPs and their anticancer properties, three different samples of Au NPs were prepared from each extract by varying the concentration of extracts while keeping the amount of precursor constant. In both cases, high-quality, spherical-shaped NPs were obtained, only at a high concentration of the extract, whereas at lower concentrations, larger-sized, irregular-shaped NPs were formed. Furthermore, the as-prepared Au NPs were evaluated for the anticancer properties against two different cell lines including MDA-MB-231 (breast cancer) and HCT 116 (colorectal cancer) cell lines. GE-conjugated Au NPs obtained by using a high concentration of the extract demonstrated superior anticancer properties when compared to NSE-conjugated counterparts.

Abandoned Mine Lands Reclamation by Plant Remediation Technologies

Abandoned mine lands (AMLs), which are considered some of the most dangerous anthropogenic activities in the world, are a source of hazards relating to potentially toxic elements (PTEs). Traditional reclamation techniques, which are expensive, time-consuming and not well accepted by the general public, cannot be used on a large scale. However, plant-based techniques have gained acceptance as an environmentally friendly alternative over the last 20 years. Plants can be used in AMLs for PTE phytoextraction, phytostabilization, and phytovolatilization. We reviewed these phytoremediation techniques, paying particular attention to the selection of appropriate plants in each case. In order to assess the suitability of plants for phytoremediation purposes, the accumulation capacity and tolerance mechanisms of PTEs was described. We also compiled a collection of interesting actual examples of AML phytoremediation. On-site studies have shown positive results in terms of soil quality improvement, reduced PTE bioavailability, and increased biodiversity. However, phytoremediation strategies need to better characterize potential plant candidates in order to improve PTE extraction and to reduce the negative impact on AMLs.

Phytoremediation of wastewater using aquatic plants, A review

Disposal of waste products and residuals into the natural water bodies can havefatal consequences for aquatic ecosystems, posing severe threats to naturalhabitats and human health. Natural treatment systems are the most suitabletreatment technologies for various types of wastewaters, which has attracted muchattention in recent years. Phytoremediation is a plant-based technique used toeliminate or recover surplus nutrients in contaminated environments. The use ofaquatic plants in wastewater phytoremediation is very efficient due to they have avery significant ability for assimilating and degrading contaminants (e.g., nitrates,phosphates, and heavy metals). Phytoremediation is a relatively new technologythat is considered as an operational, efficient, new, and environmentally friendlytechnology that is still in the early stages of development and optimization. Itsapplication on a large scale is still limited. It should also be noted that a clear visionof this innovation should be taken into account and, accurate data should be madeavailable to the public as it will enhance its efficiency as a manageable solution inthe worldwide. Additionally, phytoremediation has been evaluated as a separatelow-tech and environmentally friendly green option compared to the existingtechnologies. The present study attempts to review the recently published literatureto explain phytoremediation technology and its advantages in purifying water andwastewater.

Ecofriendly Synthesis of Silver Nanoparticles Using Aqueous Extracts of Zingiber officinale (Ginger) and Nigella sativa L. Seeds (Black Cumin) and Comparison of Their Antibacterial Potential

Applications of chemical synthetic methods for the preparation of metal nanoparticles involve toxic reagents, which are hazardous to both humans and the environment. On the other hand, ecofriendly plant-based techniques offer rapid, non-toxic, and suitable alternatives to the traditional methods. Herein, we report an eco-friendly method for the preparation of silver nanoparticles (Ag NPs) using two different aqueous extracts of Zingiber officinale (ginger) and Nigella sativa L. seeds (black cumin). Successful preparation of Ag NPs was confirmed by X-ray diffraction, ultraviolet–visible (UV-Vis) spectroscopy, and energy dispersive spectroscopy (EDX). Transmission electron microscopy (TEM) analysis revealed that Nigella sativa L. seed extract (NSE) produced a smaller size of NPs (~8 nm), whereas the ginger extract (GE) led to the formation of slightly larger Ag NPs (~12 nm). In addition, to study the effect of concentration of the extract on the quality of resulting NPs, two different samples were prepared from each extract by increasing the concentrations of the extracts while using a fixed amount of precursor (AgNO3). In both cases, a high concentration of extract delivered less agglomerated and smaller-sized Ag NPs. Furthermore, the antibacterial properties of as-prepared Ag NPs were tested against different bacterial strains. Notably, despite the slightly better quality of Ag NPs obtained from NSE (NSE-Ag), NPs prepared by using GE (GE-Ag) demonstrated superior antibacterial properties. In case of the plant-extract-based synthesis of nanoparticles, it is widely reported that during the preparation, the residual phytomolecules remain on the surface of resulting NPs as stabilizing agents. Therefore, in this case, the high antibacterial properties of GE-Ag can be attributed to the contributing or synergetic effect of residual phytomolecules of GE extract on the surface of Ag NPs, since the aqueous extract of GE has been known to possess higher intrinsic bactericidal properties when compared to the aqueous NSE extract.

Time-frequency features of grapevine’s xylem acoustic emissions for detection of drought stress

In cultures like grapevine, growth, yield and fruit quality depend on precise regulation of water stress using precision irrigation. In arid climates with seasonal droughts, karst areas and porous stony soils it is difficult to assess irrigation thresholds only based on soil water balance, requiring novel, plant-based techniques of early drought stress detection. In plants, water stress causes an increase in evapotranspiration rate, subjecting the water in the xylem conduits to high tension. This creates cavitations, leading to xylem embolization, loss of hydraulic conductivity and possibly plant death. A promising emerging technology for automated, non-invasive field monitoring of xylem cavitations is acoustic emission (AE) testing. Passive piezoelectric sensors on trunk are used to capture intermittently appearing AE, occurring in ultrasonic frequency-band from 100 kHz to 1 MHz. To make AE suitable as an input for precision irrigation, we present a novel AE time-frequency feature set for discrimination between normal and drought stress conditions. The proposed feature extraction method entails software-compensation of sensor's frequency response, enabling the wide-band frequency-analysis with miniature resonant high-frequency piezoelectrics. The signal analysis revealed three characteristic groups of AEs, differentiated by their spectral composition: single-component, multi-component, and broadband AEs. In conditions of increased water stress, single-component emissions cluster around 200 kHz, and multi-component emissions group between 200 and 600 kHz, forming discriminant time-frequency signatures. The study entails an extensive set of laboratory pot-plant dehydration experiments on four different grapevine cultivars, verifying the selectivity, sensitivity and repeatability of the extracted feature set. It proved sensitive enough for detection of drought stress corresponding to moderate leaf water potentials ranging between −0.7 and −1.2 MPa.

Assessing the Effect of Diesel Fuel on the Seed Viability and Germination of Medicago sativa Using the Event-Time Model.

The remediation of contaminated sites using plant-based techniques has gained increasing attention in recent decades. However, information on the effects of contaminant imbibition on seed viability and germination rates are often lacking in the literature. To this end, our research investigated, by means of an event-time model, the effect of diesel fuel imbibition on the seed viability and germination rate of Medicago sativa, a plant species with great potential for remediation of organic contaminants. The event-time model provided an accurate and biologically relevant method for analysing germination data. Our results reveal that the direct imbibition of diesel fuel by M. sativa seeds for ≤48 h, or their exposure to soil diesel fuel concentrations of 0–10 g/kg diesel fuel, affects their germination rates, as shown by increasing t50 values from 90.6 (±2.78) to 114.2 (±2.67) hours, without significantly affecting seed viability. On the other hand, diesel fuel imbibition of longer duration, or the exposure of M. sativa seeds to ≥20 g/kg diesel fuel-contaminated soils, leads to no further effect on time to seed emergence. Instead, these conditions compromise seed viability, resulting in a decrease in the proportion of germinated seeds from 0.91 (±0.03) in 10 g/kg diesel fuel contaminated soil to 0.84 (±0.04) and 0.70 (±0.05) in 20 and 30 g/kg diesel fuel-contaminated soils, respectively. The fact that low concentrations of diesel fuel and 0–48 h of direct imbibition delayed seed emergence without adversely affecting the percentage of viable seeds suggests that this inhibitory effect on germination at low diesel fuel exposure could be attributed more to physical constraints rather than biological damage on the seeds. The models used in this study provide an accurate and biologically relevant method for the analyses of germination data. This is vital since expensive germination experiments, be it in the field of toxicology or agriculture, deserve to be accurately analysed.

Quality Improvement of Reverse Osmosis Waste Waterthrough Plant-Based Techniques: A Mini-Review

Water is a scarce resource in this millennium, especially clean water. Reverse osmosis (RO) technology is widely applied to achieve this goal. But, reverse osmosis waste water (ROWW) cannot be further utilized, due to the presence of a high concentration of salts, heavy metals, and pollutants of feed water. The solution to this problem may lie in employing plants for this very purpose that is phytoremediation. Phytoremediation converts this waste water into usable water with the help of plants. This is an eco-friendly technique that decontaminates the waste water in a very economical way. This mini-review thus, emphasizes on quality improvement of RO waste water through plant-based techniques with a special focus on recent studies carried out in this area. Keywords: Phytodegradation, Phytoextraction, Phytoremediation, Phytovolatilization, Reverse osmosis (RO), Reverse osmosis waste water (ROWW), Rhizodegradation.

Comparative study of Zn-phytoextraction potential in guar (Cyamopsis tetragonoloba L.) and sesame (Sesamum indicum L.): tolerance and accumulation

Phytoextraction is a plant-based technique for removing heavy metals from polluted soil. The experiment reported in this paper was undertaken to study the Zn phytoextraction potential of Cyamopsis tetragonoloba in comparison with Sesamum indicum in the framework of a pot experiment. Plants were subjected to six Zn concentrations (0, 50, 100, 200, 300, 400 mg kg−1 soil) for 90 days to investigate Zn tolerance and accumulation. Results demonstrated that, at higher Zn levels, root, shoot lengths, biomass and chlorophyll content were all significantly reduced (p < 0.05). A steady increase in Zn accumulation with increasing concentration in soil was observed for all treatments. Both plant species had relatively high Zn tolerance and accumulation capacity, with C. tetragonoloba being more tolerant and having higher Zn accumulation than S. indicum. At 400 mg Zn kg kg−1, accumulation of Zn in C. tetragonoloba was highest in the root (439.33 mg kg−1) followed by stem (436.00 mg kg−1), leaf (40.67 mg kg−1) and pod (11.33 mg kg−1). Considering the rapid growth, high biomass, tolerance, accumulation efficiency, bioconcentration factor (BCF), bioaccumulation coefficient (BAC) and translocation factor (TF) (all greater than 1) established C. tetragonoloba as a potential candidate plant for Zn phytoextraction.

Leaf thickness to predict plant water status

Plant-based techniques to measure crop water status offer advantages over soil-based methods. The objective of this study was to quantify the relationship between leaf thickness measurements, as a promising plant-based technique, with leaf relative water content (RWC) and assess the model across different species and leaf positions. The relationship between RWC and relative thickness (RT) was determined on corn (Zea mays L.), sorghum (Sorghum bicolor (L.) Moench), soybean (Glycine max (L.) Merr.), and fava bean (Vicia faba L.). RWC was calculated as measured leaf water content/leaf water content at full turgor, and RT as measured leaf thickness/leaf thickness at full turgor. Two leaves from the top, middle, and bottom of five plants of each species were collected at 60 days of age. Leaf samples brought to full turgor were left to dehydrate in a lab. Leaf thickness was measured using a magnetic field sensor and water content using weight loss. The RWC-RT relationship showed a distinct breakpoint, which we hypothesise coincides with the turgor loss point. Linear piecewise modelling was used to regress RWC versus RT, resulted in models explaining 86–97% of the variations. The precision was improved by including leaf position on the plant in the model. The piecewise model parameters were related to salt tolerance of the species, which is also an indicator of drought resistance. Generally, the species with greater drought and salinity tolerance had a larger RT at the breakpoint.

State of the Art of Phytoremediation in Brazil—Review and Perspectives

The pollution of terrestrial and aquatic environments with heavy metals is a serious concern on a worldwide scale. Trace elements can be highly toxic and carcinogenic for human health while also detrimental to animal and plant life of ecosystems surrounding contamination hotspots. Phytoremediation is a low-cost and environment-friendly plant-based technique to alleviate polluted areas, which constitutes a viable alternative to other complex, costly, and often harmful traditional methods. Phytoremediation is particularly interesting for Brazil, given the country’s rich biodiversity and climate. This mini-review covers some of the most important results in phytoremediation studies carried out in Brazil to date, with a particular focus on the potential of the Brazilian flora for phytostabilization and phytoextraction, the two main subcategories of phytoremediation. Moreover, it includes data from two previously unpublished trials about phytoremediation of metal-polluted soil and water with vetiver grass and four wetland macrophytes (water hyacinth, creeping river grass, alligator weed, and water lettuce).

Plant‐Based Plume‐Scale Mapping of Tritium Contamination in Desert Soils

Plant‐based techniques were tested for field‐scale evaluation of tritium contamination adjacent to a low‐level radioactive waste (LLRW) facility in the Amargosa Desert, Nevada. Objectives were to (i) characterize and map the spatial variability of tritium in plant water, (ii) develop empirical relations to predict and map subsurface contamination from plant‐water concentrations, and (iii) gain insight into tritium migration pathways and processes. Plant sampling [creosote bush, Larrea tridentata (Sessé &amp; Moc. ex DC.) Coville] required one‐fifth the time of soil water vapor sampling. Plant concentrations were spatially correlated to a separation distance of 380 m; measurement uncertainty accounted for &lt;0.1% of the total variability in the data. Regression equations based on plant tritium explained 96 and 90% of the variation in root‐zone and sub‐root‐zone soil water vapor concentrations, respectively. The equations were combined with kriged plant‐water concentrations to map subsurface contamination. Mapping showed preferential lateral movement of tritium through a dry, coarse‐textured layer beneath the root zone, with concurrent upward movement through the root zone. Analysis of subsurface fluxes along a transect perpendicular to the LLRW facility showed that upward diffusive‐vapor transport dominates other transport modes beneath native vegetation. Downward advective‐liquid transport dominates at one endpoint of the transect, beneath a devegetated road immediately adjacent to the facility. To our knowledge, this study is the first to document large‐scale subsurface vapor‐phase tritium migration from a LLRW facility. Plant‐based methods provide a noninvasive, cost‐effective approach to mapping subsurface tritium migration in desert areas.

Effects of Sample Preparation, Growth Stage, and Observer on Microhistological Analysis of Herbivore Diets

LYON, L. J. 1968. An evaluation of density sampling methods in a shrub community. J. Range Manage. 21:16-20. MCCULLOCH, C. Y. 1955. Utilization of winter browse on wilderness big game range. J. Wildl. Manage. 19:206-215. MERRILL, E. H., H. F. MAYLAND, AND J. M. PEEK. 1980. Effects of a fall wildfire on herbaceous vegetation on xeric sites in the Selway-Bitterroot Wilderness, Idaho. J. Range Manage. 33:363-367. MUEGGLER, W. F. 1965. Ecology of seral shrub communities in cedar-hemlock zones of northern Idaho. Ecol. Monogr. 35:165-185. MUTCH, R. W. 1974. I thought forest fires were black! West. Wildlands 1(1):16-21. OHMANN, L. F., AND D. F. GRIGAL. 1979. Early revegetation and nutrient dynamics following the 1971 Little Sioux Forest Fire in northeastern Minnesota. For. Sci. Monogr. 21. 80pp. PEEK, J. M., D. L. URICH, AND R. J. MACKIE. 1976. Moose habitat selection and relationships to forest management in northeastern Minnesota. Wildl. Monogr. 48. 65pp. RUTHERFORD, M. C. 1979. Plant-based techniques for determining available browse and browse utilization: a review. Bot. Rev. 45:203-228. SIEGEL, S. 1956. Nonparametric statistics for the behavioral sciences. McGraw-Hill Book Co., New York, N.Y. 312pp. STEEL, R. G. D., AND J. H. TORRIE. 1960. Principles and procedures of statistics. McGraw-Hill Book Co., New York, N.Y. 481pp. WRIGHT, H. A. 1978. The effect of fire on vegetation in ponderosa pine forests. Texas Tech. Univ., College Agr. Sci. Publ. T-9-199. 21pp.

Tiller Length vs. Tiller Weight: Applications to Plant Growth Studies

Tiller Length vs. Tiller Weight: Applications to Plant Growth Studies

Plant-based techniques for determining available browse and browse utilization: A review

Usually satisfactory answers for browse availability will require wellconsidered use of available techniques. Despite the wide range of available techniques, more recent emphasis has clearly fallen on deriving specific relations to predict browse amounts particularly in heterogeneous plant communities. Advantages of such relations are that acceptable precision is usually possible and the application is nondestructive. However, the work effort required for valid estimates is often great and there is difficulty in expressing compounded error of estimates per unit ground area. Since some quicker methods may not provide the information required adequately, the operations research question of whether it should be done at all is very important when setting out to define objectives and priorities in a restricted field research programme. One of the main areas in which interest has been recently shown and in which further research may be expected is in deriving whole plant relations for predicting browse at different height levels.