Conservation of important plants from the Ionian Islands at the Balkan Botanic Garden of Kroussia,N Greece: using GIS to link the in situ collection data with plant propagation and <Emphasis Type="Italic">ex situ</Emphasis> cultivation

The Balkan Botanic Garden of Kroussia (BBGK) is dedicated to the ex situ conservation of native plants of Greece and the Balkans. The BBGK has formulated a conservation strategy for the collection of wild plant material for propagation, prioritizing mainly the endemic, rare, endangered, threatened and vulnerable plants of Europe found in different regions of Greece. Its aim is to contribute to the implementation of Target 8 of the Global and European Strategies for Plant Conservation at local, regional and international scales. In order to (i) define the ecological profile of the in situ requirements preferred and/or tolerated by each selected species, (ii) develop rapid and effective species-specific propagation protocols, and (iii) improve the cultivation of species of conservation concern in BBGK’s nurseries and ex situ conservation sections, geographical coordinates and in situ collection data obtained for each taxon were imported into a Geographic Information System environment (GIS). This information was then linked with several digital GIS thematic layers, including topographic, geological, edaphic, climatic, precipitation and temperature data derived from digital databases. Based on this approach, sexual and asexual propagation of plants from the Ionian Islands were conducted and rapid and effective baseline protocols were developed for 29 taxa (species and subspecies); four are presented here in detail and species-specific ex situ propagation and cultivation guidelines are given. Most of the taxa originating from the Ionian Islands were propagated by cuttings (55.2%) or seeds (34.5%), while the rest were propagated by root division at a rate from 1.7 to 2. The first round of propagation achieved a success rate ranging from 15 to 50% for 3 taxa, from 60 to 80% for 8 taxa and from more than 80 to 100% for 16 taxa, while the ex situ cultivation of the wild and propagated plant material has, so far, been successful. The application of GIS exemplified here presents a sensible and invaluable tool with a broad-scale potential in enhancing the prospects of the ex situ conservation of priority species collected from diverse environmental conditions in man-made habitats such as botanic gardens.     

Strategies for agrobiodiversity conservation and promotion: a case from Yunnan, China

This paper deals with strategies for agrobiodiversity conservation and promotion based on studies on four plant groups (selected from 50 plant groups) occurring in the Yunnan Province of China. These plants are edible konjac (Amorphophallus), medicinal Paris, Musella lasiocarpa and wild tea (Camellia sinensis and its wild relatives), including their cultivars and wild populations. After analyzing the target plants, we conclude that the following strategies should be adopted to conserve and promote agrobiodiversity: (1) in situ conservation of agrobiodiversity, including habitat protection of wild populations, maintenance of native species and varieties in traditional agroecosystems, and relevant environmental education; (2) ex situ conservation and promotion of agrobiodiversity, including establishment of living collections and germplasm banks, and introduction of species and varieties into agroecosystems for agricultural practice; and (3) promotion and conservation of agrobiodiversity through sustainable uses, including technique development of propagation, cultivation, pest and disease control, on farm and off farm management, and other activities such as new variety breeding and scientific studies. Strategies developed here will be helpful to conserve and promote agrobiodiversity at agroecosystem, species, variety or landrace, and management system levels.     

Conservation In vitro of threatened plants—Progress in the past decade

Summary In vitro techniques have found increasing use in the conservation of threatened plants in recent years and this trend is likely to continue as more species face risk of extinction. The Micropropagation Unit at Royal Botanic Gardens, Kew, UK (RBG Kew) has an extensive collection of in vitro plants including many threatened species from throughout the world. The long history of the unit and the range of plants cultured have enabled considerable expertise to be amassed in identifying the problems and developing experimental strategies for propagation and conservation of threatened plants. While a large body of knowledge is available on the in vitro culture of plants, there are limited publications relating to threatened plant conservation. This review highlights the progress in in vitro culture and conservation of threatened plants in the past decade (1995–2005) and suggests future research directions. Works on non-threatened plants are also included wherever methods have applications in rare plant conservation. Recalcitrant plant materials collected from the wild or ex situ collections are difficult to grow in culture. Different methods of sterilization and other treatments to establish clean material for culture initiation are reviewed. Application of different culture methods for multiplication, and use of unconventional materials for rooting and transplantation are reviewed. As the available plant material for culture initiation is scarce and in many cases associated with inherent problems such as low viability and endogenous contamination, reliable protocols on multiplication, rooting, and storage methods are very important. In this context, photoautotrophic micropropagation has the potential for development as a routine method for the in vitro conservation of endangered plants. Long-term storage of material in culture is challenging and the potential applications of cryopreservation are significant in this area. Future conservation biotechnology research and its applications must be aimed at conserving highly threatened, mainly endemic, plants from conservation hotspots.     

Influence of Clonal Variation on the Efficiency of Arundo donax Propagation Methods

The recent growth of interest in Arundo donax L. (Giant reed) as an energy crop is due to its great vegetative vigor and high biomass productivity. This perennial rhizomatous plant is able to grow in a wide range of pedo-climatic conditions and it has been employed by man for a great number of purposes. This has promoted its worldwide diffusion, despite its sexual sterility. Field establishment represents the most expensive phase of the whole cultivation cycle, because of the high cost of the propagules. In this work three agamic propagation methods, rhizome transplantation, hydroponic cultivation, and in vitro propagation, were compared with the aim of improving their efficiency, and reducing costs and time required. We focused our attention on in vitro and hydroponic cultivation, finding clones characterized by a high response to these propagation methods. In vitro propagation is the most widespread technique adopted in the large-scale production of propagules; according to our results hydroponic cultivation also appears to be a valid and cheap propagation method, making it possible to obtain in about 2 months, vigorous plants ready to be transplanted into the field. We found a strong effect of the clone used on the success rate of the specific propagation method, suggesting that clonal selection could be particularly useful in improving the efficiency of propagation techniques, contributing to cost reduction. Evaluation of field performance of plants propagated by tissue culture is an important matter, considering the possible residual effects of hormones on plants’ growth, and the importance of first year growth for field establishment. These experiments highlighted the lower biomass production from plants obtained by tissue culture. A novel cytokinin-like hormone, meta-topolin, was tested in vitro, in a preliminary study to evaluate its possible use for A. donax L. propagation.

     

Exploring plant tissue culture in Withania somnifera (L.) Dunal: in vitro propagation and secondary metabolite production

Withania somnifera (L.) Dunal (family: Solanaceae), commonly known as “Indian Ginseng”, is a medicinally and industrially important plant of the Indian subcontinent and other warmer parts of the world. The plant has multi-use medicinal potential and has been listed among 36 important cultivated medicinal plants of India that are in high demand for trade due to its pharmaceutical uses. The medicinal importance of this plant is mainly due to the presence of different types of steroidal lactones- withanolides in the roots and leaves. Owing to low seed viability and poor germination, the conventional propagation of W. somnifera falls short to cater its commercial demands particularly for secondary metabolite production. Therefore, there is a great need to develop different biotechnological approaches through tissue and organ culture for seasonal independent production of plants in large scale which will provide sufficient raw materials of uniform quality for pharmaceutical purposes. During past years, a number of in vitro plant regeneration protocols via organogenesis and somatic embryogenesis and in vitro conservation through synthetic seed based encapsulation technology have been developed for W. somnifera. Several attempts have also been made to standardize the protocol of secondary metabolite production via tissue/organ cultures, cell suspension cultures, and Agrobacterium rhizogenes-mediated transformed hairy root cultures. Employment of plant tissue culture based techniques would provide means for rapid propagation and conservation of this plant species and also provide scope for enhanced production of different bioactive secondary metabolites. The present review provides a comprehensive report on research activities conducted in the area of tissue culture and secondary metabolite production in W. somnifera during the past years. It also discusses the unexplored areas which might be taken into consideration for future research so that the medicinal properties and the secondary metabolites produced by this plant can be exploited further for the benefit of human health in a sustainable way.     

Arbuscular mycorrhizal morphology and dark septate fungal associations in medicinal and aromatic plants of Western Ghats, Southern India

We investigated roots of 107 medicinal and aromatic plants (MAPs) in the Western Ghats region of Southern India for arbuscular mycorrhizal (AM) and dark septate endophyte (DSE) associations. Of the 107 MAPs belonging to 98 genera in 52 families examined, 79 were AM and 38 harbored a DSE association. Typical Arum- and Paris-type mycorrhizas are first reported in the presumed nonmycorrhizal family Amaranthaceae. Similarly, DSE associations are recorded for the first time in nine plant families and 37 plant species. Thirty MAPs had both AM and DSE associations. The number of MAPs having Arum-type mycorrhiza was greater than those having Paris-type. This was more prominent among herbaceous plants than in trees where the Paris-type was predominant. Similarly, the Arum-type was more prevalent in annuals than in perennials. DSE associations were more frequent in herbs and perennials compared to other MAPs.     

Method of clonal micropropagation of different willow species and hybrids

Conditions of cultivation and micropropagation of selected biotypes of five willow species (Salyx dasyclados Wimm., S. caspica Pall., S. triandra L., S. purpurea L., and S. viminalis L.) and two hybrids (×S. acuminata S. and ×S. palustris Host.) were optimized. Data on in vitro propagation of S. caspica, S. triandra, S. purpurea together with hybrids S. acuminata and S. palustris were obtained for the first time. It has been demonstrated that the outcome of cultivation and propagation of willows strongly depends on genotypic peculiarities of initial plants. The optimal terms of isolation and sterilization of single-node segments for obtaining 50–75% of aseptic viable developing cultures were estimated. The nutritive media were selected providing induction of stem development (to 67%), their rooting (to 91%), elongation (to 3–6 cm), and multiplication (propagation coefficient of 4). The designed method (adopted to different genotypes) can be applied for obtaining aseptic in vitro cultures serving as initial plant material for genetic transformation and mass propagation of plants with new agriculturally valuable characteristics which are of interest for construction of bioenergetic plantations and for needs of the paper industry.     

Conservation and Propagation of High Altitude Medicinal and Aromatic Plant: Hedychium spicatum

The micropropagation of H.spicatum, a medicinal and aromatic plant was investigated as an option for conservation and propagation, as wild populations are fast depleting. The source of raw material is rhizomes of plants that are collected from the wild. There is no planned cultivation of the plant. Multiple shoot cultures were established on MS medium supplemented with BAP and IAA from the pre-existing buds on the rhizome. Prolonged cultivation on the same medium or transfer to hormone free medium induced roots/rhizome formation; liquid medium proved more suitable. Greenhouse hardened plants were transferred to field. A successful protocol with 99% root formation and 80–85.5% field survival has been formulated.     

In vitro regeneration using twin scales for restoration of critically endangered aquatic plant Crinum malabaricum Lekhak & Yadav: a promising source of galanthamine

This study intended to develop a significant in vitro regeneration protocol for sustainable propagation, conservation and re-establishment of critically endangered aquatic plant species Crinum malabaricum Lekhak & Yadav (Malabar river lily). This plant is the natural source of galanthamine, the drug to treat Alzheimer’s disease. We present a scientific understanding, emphasizing the use of twin scales (separated from the large parent bulb) in direct regeneration of new shoots and proliferation of bulblets assisted by nutrients supply. The meristematic region of the bulb plate, present between the scales was activated using cytokinins to produce shoots (maximum 12 shoots per twin scale) on full strength Murashige and Skoog’s (MS) medium augmented singularly with 2.0 mg L^?1 6-benzylaminopurine (BAP). Upon subculturing of shoots on diverse concentrations of plant growth regulators (BAP and IAA/NAA), BAP alone at 2.0 mg L^?1 was served optimum for the better proliferation of shoots (53 shoots). The regenerated shoots were rooted in vitro on half strength MS medium fortified with various types of auxins. Highest number of roots (11.6 within 4 weeks) and bulblets (after 3 months) resulted with 1.0 mg L^?1 Indole-3-butyric acid (IBA) under in vitro conditions. The rooted plants were hardened in the greenhouse and finally transferred to the natural stream with 83% survival rate. The SCoT (start codon targeted) and ISSR (inter simple sequence repeats) marker analysis of in vitro raised and mother plants confirmed the genetic stability of tissue cultured plants and the reliability of present protocol for C. malabaricum. It is the foremost report on in vitro regeneration and genetic fidelity analysis for restoration of this critically endangered aquatic plant using twin scale technique. The study could help in ex situ conservation, reintroduction and restoration of C. malabaricum population in its natural habitat.

     

Conservation,propagation, and redistribution (CPR) of Hill’s thistle: paradigm for plant species at risk

Cryopreservation is a valuable tool that could potentially create an alternate plant preservation strategy for species at risk such as Hill’s thistle. The present study is focused on a successful paradigm involving conservation, propagation and redistribution (CPR), emaphasizing the usefulness of cryopreservation techniques for plant conservation using Hill’s thistle (Cirsium hillii. (Canby) Fernald). A cryopreservation protocol was established using the droplet-vitrification method for 5-week-old shoot tips of in vitro grown cultures. More than 90% of shoot tips showed regrowth and nearly all regenerated plants were able to survive in the greenhouse. The survival, growth, and development of plants from cryopreserved shoot buds and their performance in field conditions were all comparable or better than the plants from non-cryopreserved buds. Reintroduced plants flowered following overwintering and the magnitude of flowering was site dependent with ca. 80% flowering observed in one site. The site dependent flowering patterns were assessed using phytohormone profiling and compared to herbivory, a common biotic stressor of these plants. Lower tryptophan concentrations led to higher flowering except in alvars, where the limestone resisted root penetration resulting in poor flowering. The presence of tryptamine in the greenhouse acclimatized or alvar field leaves suggested the preparedness of the plants for herbivory/grazing. Serotonin and melatonin concentrations were lower in flowering plants and in sites where the biotic/abiotic stress was minimal. This study provides evidence of the effectiveness of the CPR model in species recovery programs for endangered species. Physiological characterization of plants developed from cryopreserved tissues can be useful for fundamental and applied research in stress adaptation and reproductive biology of plants.

     

Conservation of medicinal plants of Western Ghats,India and its sustainable utilization through <Emphasis Type="Italic">in vitro</Emphasis> technology

Climate change, alien species, and use of land for intensive farming and development are causing severe threat to the plant genetic diversity worldwide. Hence, conservation of biodiversity is considered fundamental and also provides the livelihoods to millions of people worldwide. Medicinal plants play a key role in the treatment of a number of diseases, and they are only the source of medicine for majority of people in the developing world. The tropical regions of the world supply the bulk of current global demand for “natural medicine,” albeit with increasing threat to populations in the world and its genetic diversity. India is a major center of origin and diversity of crop and medicinal plants. India poses out 20,000 species of higher plants, one third of it being endemic and 500 species are categorized to have medicinal value. The Western Ghats is one of the major repositories of medicinal plants. It harbors around 4,000 species of higher plants of which 450 species are threatened. Currently, the number of species added to the red list category in this region is increasing, and the valuable genetic resources are being lost at a rapid rate. Demand for medicinal plants is increasing, and this leads to unscrupulous collection from the wild and adulteration of supplies. Providing high-quality planting material for sustainable use and thereby saving the genetic diversity of plants in the wild is important. During the last 25 years of intensive research, Tropical Botanic Garden and Research Institute has developed in vitro protocol for rapid regeneration and establishment of about 40 medicinally important rare and threatened plants of Western Ghats. In situ conservation alone would not be effective in safeguarding these important species. Thus, utilizing the biotechnoligical approach to complement ex situ conservation program is becoming vital. Propagating biotechnology tools in plant conservation program is a prerequisite to succeed in sustainable use and to complement the existing ex situ measures. In addition to propagation, storage of these valuable genetic resources is equally important. In vitro slow growth of 35 species and cryopreservation using embryo/meristem/seed in 20 different species of rare medicinal plants of this region is accomplished. Plants developed in vitro of ten medicinal plants, which have restricted distribution, were reintroduced in the natural habitat as well.     

An improved protocol for in vitro multiplication of Bacopa monnieri (L.)

A cost-effective and efficient protocol has been described in the present work for large scale and rapid in vitro propagation of a valuable medicinal herb Bacopa monnieri (L.) by shoot bud proliferation on internodal segments isolated from field grown mature plants. This shooting was achieved on low concentration of cytokinin with BAP 1.0 mg/l and Kn 0.5 mg/l within 3 weeks of inoculation contrary to earlier reports where auxin is also used in combination with cytokinin. Normally internodes gives rise to a clump of shoots (18 shoots). On an average within a period of three subcultures the internode explant generated 324 shoots thereby improving the economics of the cost of the plants produced and time required. For rooting this is a first report of its growth in a liquid culture. The regenerated plants resemble the mother plants in the general habitat without any morphological variation. This paper reports a very simple, reproducible procedure for in vitro propagation of Bacopa monnieri (L.) that can be used to form a foundation stock of elite plant material for large-scale cultivation.     

Conservation strategies for threatened medicinal plant – Barleria prionitis L. – using in vitro and ex vitro propagation techniques

Over-utilisation and continuous depletion of medicinal plants have affected their supply and loss of genetic diversity. Hence the current study is based on conservation strategies for threatened medicinal plants with special reference to Barleria prionitis L. using in vitro and ex vitro propagation techniques. We have developed here a protocol for plant regeneration of Barleria prionitis L. We have also developed an efficient system of vegetative propagation of Barleria prionitis L. through stem cuttings using revive rooting hormones. These studies can be useful for conservation strategies of this important medicinal plant.     

Fertiliser application positively affects plants performance but reduces seed viability in seashore mallow (Kosteletzkya pentacarpos): implication for biomass production and species conservation

Kosteletzkya pentacarpos seashore mallow, is recognised as an important plant species for several industrial applications, especially in North America and Asia. In Europe, seashore mallow is highly threatened and subject of conservation actions (e.g. reintroduction). In order to define appropriate multipurpose cultivation protocols, suitable for biomass production and for conservation purposes, we investigated the effect of varying levels of soil salt content and nutrient availability on seashore mallow. As expected, seashore mallow had the best performance in terms of growth rate, flowering and fruit production when fertiliser was applied, while salt had only limited effects. Interestingly, seeds produced by fertilised plants showed a lower germination performance and higher mortality than seeds developed from non‐fertilised plants. Our results highlight a trade‐off between parental plant growth and seed performance, the former being enhanced and the latter being reduced by fertiliser application. The causes of this trade‐off are related to a transgenerational maternal effect of fertiliser application that has important implications for seashore mallow cultivation. Biomass production benefits from fertiliser application but if the quality of seeds and the fitness of the next generation are major objectives (e.g. seed production and species conservation), fertiliser application is not recommended.     

<Emphasis Type="Italic">In Vitro</Emphasis> Preservation of Spanish Biodiversity

Spanish territories contain many of the hot spots of plant biodiversity among European countries. Most of the Spanish territory is found in the Mediterranean basin and in the Canary Islands, a region of great floral singularity and diversity (Macaronesian bioregion). Therefore, an important effort must be made to contribute to its conservation. Several strategies can be considered, but seed conservation under standard conditions is the most resource-efficient method. However, the application of this methodology is not always possible for recalcitrant seeds or species for which vegetative propagation is necessary or convenient under some circumstances. Micropropagation is one of the measures suggested for preserving endangered species. During the 1990s, several in vitro culture protocols for Spanish endemics were established. The main purpose of this strategy was to obtain a considerable number of individuals to reduce the loss of natural populations. Likewise, diverse slow growth protocols were developed for this material. However, these efforts usually did not lead to the establishment of in vitro collections. The advantages and disadvantages of the in vitro conservation strategy will be reviewed for some cases. The establishment of the in vitro protocols together with the development of cryopreservation techniques created the ideal conditions to generate cryogenic collections. In this paper, we review the knowledge and experience accumulated during the last decades in micropropagation, slow growth, and cryopreservation for Spanish plant wild species. Their application in the development ex situ collections and their contribution toward an integrated system to conserve threatened species will be discussed.     

Induction of a dwarf phenotype with IBH1 may enable increased production of plant‐made pharmaceuticals in plant factory conditions

Year‐round production in a contained, environmentally controlled ‘plant factory’ may provide a cost‐effective method to produce pharmaceuticals and other high‐value products. However, cost‐effective production may require substantial modification of the host plant phenotype; for example, using dwarf plants can enable the growth of more plants in a given volume by allowing more plants per shelf and enabling more shelves to be stacked vertically. We show here that the expression of the chimeric repressor for Arabidopsis AtIBH1 (P35S:AtIBH1SRDX) in transgenic tobacco plants (Nicotiana tabacum) induces a dwarf phenotype, with reduced cell size. We estimate that, in a given volume of cultivation space, we can grow five times more AtIBH1SRDX plants than wild‐type plants. Although, the AtIBH1SRDX plants also showed reduced biomass compared with wild‐type plants, they produced about four times more biomass per unit of cultivation volume. To test whether the dwarf phenotype affects the production of recombinant proteins, we expressed the genes for anti‐hepatitis B virus antibodies (anti‐HBs) in tobacco plants and found that the production of anti‐HBs per unit fresh weight did not significantly differ between wild‐type and AtIBH1SRDX plants. These data indicate that P35S:AtIBH1SRDX plants produced about fourfold more antibody per unit of cultivation volume, compared with wild type. Our results indicate that AtIBH1SRDX provides a useful tool for the modification of plant phenotype for cost‐effective production of high‐value products by stably transformed plants in plant factory conditions.     

Density and potential utilisation of medicinal grassland plants from Abe Bailey Nature Reserve, South Africa

The Abe Bailey Nature Reserve, South Africa has been identified as a potential community resource reserve compatible with biodiversity conservation. As part of the planning and public participation phase this study investigated the potential for sustainably harvesting medicinal plants. Medicinal plant use data on local species, parts used and harvesting techniques, in collaboration with neighbouring traditional healers were collected. A census of these plants was conducted in the reserve and frequency, density and abundance were calculated. A medicinal plant rating system for assessing conservation priorities was used to combine both social-qualitative and ecological-quantitative data. Five medicinal species suitable for high impact harvesting were identified. Thirty-four species have potential to be set up as harvesting trials to determine sustainable quotas. Thirty-one medicinal species including Boophane disticha, Dicoma anomala, Eucomis autumnalis, Hypoxis hemerocallidea, Pentanisia prunelloides and Indigofera daleoides are considered to be site-specific sensitive species and should not be harvested from the reserve. Following this research an on site nursery has been started at the reserve. A multi-pronged approach involving harvesting trials, propagation and plant rescue from developments to cope with escalating demand and dwindling natural populations needs to be implemented.     

Direct somatic embryogenesis and shoot regeneration from leaves and internodes of Pluchea lanceolata (DC.) C.B. Clarke

Pluchea lanceolata (DC.) C.B. Clarke is a threatened native medicinal plant. Increasing the propagation of this plant will preserve the wild population and provide material for medicinal use. In vitro and field-collected shoots and leaves were tested for response to 2,4-dichlorophenoxyacetic acid (2,4-D) and thidiazuron (TDZ), for initiation of direct shoot regeneration (DSR), or direct somatic embryogenesis (DSE). Leaves and internodes collected from field-grown plants produced only callus, while in vitro–raised shoots exhibited DSR and DSE on Murashige and Skoog (MS) medium with 2,4-D and TDZ. Direct shoot regeneration occurred on medium with TDZ from internode and leaf segments obtained from in vitro–developed shoots. In vitro–grown shoots were rooted on half-strength MS medium with 2 mg L⁻¹ indole-3-butyric acid and acclimatized. Survival in natural conditions was 62.5% for DSE and 79% for DSR plantlets.

     

Integrating local plant resources and habitat management

The use of wild plant resources as a source of basic needs is an important aspect of multiple-use of land in much of Africa, ranging from vegetation with a low species diversity, high biomass production and resilience to harvesting (e.g.Phragmites reedbeds,Cymbopogon grasslands) through to vegetation with a high diversity of species (and plant life-forms), with a multiple of uses and often low resilience to resource harvesting (e.g. medicinal plants, pole cutting, fuelwood from Afro-montane forest). Complexity and costs of managing sustainable use of wild populations increase markedly with an increasing number of uses and resource users. It is suggested that if the primary objective of core conservation areas is accepted to be the maintenance of habitat and species diversity, then the limited money and manpower available for management of core conservation areas in southern Africa limits sustainable harvesting use of plant resources to low diversity, low conservation priority vegetation types or encroaching species. For high diversity, high conservation priority sites such as Afro-montane or Coastal evergreen forest, the emphasis must be on providing alternative sources of supply to resource users outside of core areas. Botanical gardens staff, with their horticultural experience, can play a very important role through bulking up material for supply to small farmers, herbalists and introducing additional species for agro-forestry. Botanical gardens can play a greater role in the establishment of field gene banks andex situ conservation of vulnerable species. They can also provide a valuable educational and research role on mass production techniques to boost local stocks of threatened and commercially valuable species for cultivation by local people, whether farmers or specialist users (e.g. herbalists) in the country of origin as a means of generating employment and restoring local self-sufficiency.     

Moringa oleifera Extract as a Natural Plant Biostimulant

Moringa, belonging to Moringaceae, is known as the “Miracle Tree” that has versatile uses in both animals and plants. The extract from Moringa oliefera serves as a cheap, eco-friendly, novel biostimulator, and bioenhancer that increases sustainable agriculture practices and crop production. Moringa contains several essential components like mineral nutrients, phytohormones (e.g., auxins, gibberellins, and cytokinins), vitamins, flavonols, phenols, sterols, and tannins, as well as several phytochemicals that make it highly beneficial for plants. It induces seed germination, plant growth, photosynthesis, and yields traits at a low cost. It also increases flowering, improves floral traits, fruiting, post-harvesting, and product quality of the fruit, and decreases senescence. Abiotic stresses have a detrimental effect on plant growth and development. The application of Moringa extracts on plants mitigates abiotic stress like salinity, drought, heavy metal, and heat by promoting the activity of antioxidant enzymes and increasing the content of phenols, flavonols, sugars, and osmolyte, which reduces the level of reactive oxygen species, lipid peroxidation, and electrolyte leakage. In particular, Moringa accelerates plant growth, relative water content, water use efficiency, mineral content, gas exchange traits, and yield attributes under stressful environmental conditions. Moringa serves as an essential biopesticide against plant pathogens, and is used in disease management and plant sustenance.