Healthy Planting Material Research Articles

Indigenous Biopreparations and Biocontrol Agents for Growth and Disease Management in Black Pepper Nursery

The present study was carried out at Agricultural Research Station, Thiruvalla, Kerala, India during December, 2020–July, 2021 to evaluate the efficacy of native biocontrol agents and fermented organic preparations viz; fish-jaggery extract, egg-lemon juice extract and jeevamrutha on growth enhancement and suppression of Phytophthora infection in black pepper nursery. The plants were challenge inoculated with Phytophthora capsici at the collar region. The plant growth parameters were recorded before and one month after treatment application. Results showed that a considerable increase in plant height (49.30%) and number of leaves (57.89%) with the application of bacterial antagonists A1 and S2 respectively. Application of fish-jaggery extract increased the shoot girth by 29.6%. Soil application of Trichoderma combined with spraying of bacterial antagonists A1 and S2 also increased the shoot girth considerably. Application of jeevamrutha increased the total leaf area by 49.98% and chlorophyll contents viz. chlorophyll a, chlorophyll b and total chlorophyll was also maximum with this application. Phytophthora infection at collar region was not observed in plants treated with potassium phosphonate and fish-jaggery extract. Application of egg-lemon juice extract, jeevamrutha and bioagents also recorded less infection on collar region. The study indicated the efficacy of fermented organic fertilizers and bioagents in improving plant growth and also in reducing pathogen infection at nursery stage. Hence a combination of native antagonistic microflora and indigenous biopreparations could be effectively utilized in commercial production of healthy planting materials in black pepper nurseries.

ПУТИ СНИЖЕНИЯ СЕБЕСТОИМОСТИ ПРОИЗВОДСТВА ПОСАДОЧНОГО МАТЕРИАЛА В КУЛЬТУРЕ IN VITRO

New data on the effectiveness of using the in vitro vine collection for growing healthy planting material are presented. The collection is maintained in vitro in the biotechnology laboratory of the All-Russian Research Institute for Viticulture and Winemaking named after Ya.I. Potapenko − branch of FSBSI «Federal Rostov Agricultural Research Center» by reducing the number of subcultivations. One of the directions of the laboratory's research is the search for ways to maintain the collection in conditions of slow growth, which reduces the cost of maintenance and contributes to the preservation of plants. This article presents data that the cultivation of vine planting material (micro-plants in vitro) based on the collection is more cost-effective than the full cycle (from excision meristem to obtaining planting material in vitro).

Sanitation of Apple Cultivars from AP Phytoplasma and ApMV and ACLSV Viruses Using In Vitro Culture and Cryo-Knife Therapy in Liquid Nitrogen

Systemic infections with phytoplasmas and viruses threaten the production of healthy plant material under the fruit species certification system. We tested the possibility of sanitation using in vitro culture and cryotherapy. The starting material of the cultivars Golden Delicious (clones A and B), Virginia Crab, and Panenské zlepšené was taken from in vivo plants that tested positive for apple proliferation phytoplasma. The Táborita cultivar was obtained from already established in vitro cultures that had tested positive for apple proliferation phytoplasma, apple mosaic virus, and apple chlorotic leaf spot virus. Cultivars Golden Delicious A, Virginia Crab, and Panenské zlepšené were sanitated from the phytoplasma in the first step, i.e., by sterilization and a subsequent transfer to in vitro conditions. Golden Delicious B remained infected with the phytoplasma, and both viruses, after the in vitro culture phase and together with Táborita, were subjected to cryotherapy by vitrification. In Golden Delicious B, three out of thirteen initial shoot tips regenerated after a liquid nitrogen treatment. Four mericlones were regenerated from 10 initial cryopreserved shoot tips of Táborita. None of the three pathogens were detected by PCR in the regenerated Golden Delicious B mericlones. On the contrary, in the case of Táborita, infection with all the pathogens was detected after regeneration. The results obtained indicate the potential applicability of in vitro cultivation techniques or, if necessary, subsequent cryopreservation as a method for sanitizing against systemic microbial contamination. However, further research on the relationship between pathogens and specific genotypes is needed.

An Efficient Protocol for In vitro Regeneration and Acclimatization of Banana (Musa spp.) cv. Grand Naine

Aim: The study was undertaken with a view to standardize a protocol for in vitro regeneration of Banana cv. Grand naine using shoot tip of sucker as an explant
 Methodology: In present study, explants sterilized with different sterilizing agents such as Tween-20 (1%), Bavistin (0.5-1%), Streptomycin sulphate (250 mg/L), Ascorbic acid (150 mg/L) + Citric acid (100 mg/L), HgCl2 (0.1%) and 70% ethanol.Sterilized explants were cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of plant growth hormones for shoot initiation BAP alone (1.5, 2.0, 4.0, 6.0 mg/L) and BAP (3.0 mg/L) in combination with IAA and IBA (2.0 mg/L), elongation BAP (3.0 mg/L) and NAA (1.0, 1.5, 2.0 mg/L) and rooting IAA (1.0, 1.5 mg/L) and IBA (1.0, 1.5 mg/L). Primary and secondaryhardening was done in potting mixture containing autoclaved black soil: vermicompost: cocopeat (1:1:1) and garden black soil, cocopeat and red soil (1:1:1) respectively.
 Results: In present investigation 1% Bavistin (fungicide) showed maximum respond to prevent fungal contamination. Highest shoot initiation (100%) was observed on a MS medium fortified with BAP (1.5 mg/L). Maximum shoot length (10.7 cm) was recorded on a MS medium supplemented with BAP (3.0 mg/L) + NAA (2.0 mg/L) + Activated charcoal. Maximum root initiation was observed on half strength MS medium supplemented with IAA (1.5 mg/L). In vitro regenerated plantlets hardened on the mixture of autoclaved black soil: vermicompost: cocopeat (1:1:1). After 14 weeks In vitro plantlets transferred in green house for acclimatization where, 80% survival rate was recorded.
 Conclusion: Regeneration protocol was successfully standardized. Therefore, itcan be used for large scale propagation of healthy, disease and virus free planting material and In vitro propagation helps to meet higher demand of healthy planting material within shorter period.

Effect of sterilants and plant growth regulators in regenerating commonly used cassava cultivars at the Kenyan coast

Cassava is an important root crop whose seed system is undeveloped. Micropropagation of explants in vitro has the potential of addressing the challenge of the unavailability of healthy cassava planting materials. Therefore, the study determined the effect of sterilization and plant growth regulators on cassava explants to produce certified disease-free plants of commonly used cultivars at the coast of Kenya. The apical nodes drawn from the three cultivars of cassava, Tajirika and Kibandameno and Taita, were used as explants. The sterilant sodium hypochlorite (NaOCl) at 5, 10 and 15% and 70% ethanol for 1 and 5 min and sprayed for 20 s were tested for the effect on the explant. Similarly, the effect of BAP (6-Benzyl amino purine) and NAA (1-Naphthalene acetic acid) Plant Growth Regulators (PGRs) each at 0.5, 1 and 5 mg/L under optimal conditions of sterilization was determined. Surface sterilization using 10% NaOCl followed by spraying 70% ethanol for 20 s had 85% initiation on Tajirika whereas 5% NaOCl followed by spraying 70% ethanol for 20 s had 87% and 91% initiation in Kibandameno and Taita cultivars, respectively. In Tajirika, significantly (p < 0.05) high shooting of 68% was from 5 mg/L BAP in MS media whereas approximately 50% rooting was from either 0.5 mg/L BAP or 5 mg/L NAA in MS media. Kibandameno and Taita cultivars had approximately 50% shooting from MS media without PGRs. Kibandameno had >37% rooting from 0.5 to 5 mg/L BAP or NAA in MS media whereas Taita had approximately 50% rooting from 0 to 5 mg/L NAA in MS media. This protocol showed at least 50% success rate of initiation, shooting and rooting as a rapid multiplication regeneration of Tajirika and Kibandameno and Taita cultivar plantlets with little modification of humidity and temperatures in the growth chambers. This protocol requires validation for use in large-scale production of cassava plantlets to alleviate the inadequacy of cassava planting materials among farmers.

CLONAL MICROPROPAGATION OF PAULOWNIA IN VITRO

The purpose of the article – to develop technological methods of clonal micropropagation of paulownia in vitro. Methods. Paulownia plants Paulownia Sieb. et Zucc. were the material for the research. In the course of research, generally accepted methods in plant biotechnology were used. Aseptic work was performed in the laminar box KPG-1. Murashige and Skuga (MS) were used as the basic nutrient medium for the cultivation of isolated buds and micropods. The results. The method of clonal micropropagation based on the culture of isolated apical meristems provides a high reproduction rate, maximum genetic stability and recovery of the resulting regenerating plants. The most effective scheme of sterilization of paulownia is stepwise treatment of plant material with 70% ethanol solution and 1% sodium hypochlorite solution. The yield of sterile explants was 92.5–95.0%, viability – 90.0–97.5%. At the stage of introduction into in vitro culture, the optimal nutrient medium is MS, supplemented with kinetin 1.0 mg/l and GA 0.5 mg/l, at which the reproduction rate was the highest and was 8.7–9.2. At the stage of proper micropropagation, the most intensive proliferation of shoots also occurred on the nutrient medium MS, supplemented with kinetin 1.0 mg/l and GA 0.5 mg/l, which provided the highest reproduction rate – 10.3–12.0. At the stage of rooting of micro-shoots the most optimal was the nutrient medium 1/2 MS, supplemented with a IBА of 0.5 mg/l, at which the frequency of rhizogenesis was 95.0% and formed 5.3–7.8 roots with a length of 78.5–95.2 mm. Stepwise adaptation of plants to in vivo conditions for 40 days in climatic chambers and growing in a greenhouse ensured the yield of seedlings at the level of 85.0–95.0%. Conclusions. On the basis of the carried-out experimental researches methods of clonal micropropagation paulownia in vitro, which are expedient to use for mass production of genetically homogeneous healthy planting material.

The role of healthy citrus planting materials production as a major component in the development of national citrus industry

Certified citrus seed is one of vital component on the program of good agricultural practices for the development of healthy citrus plantation. Certified seed guarantee the free systemic disease and optimum vigor planting material, thus put an impact on maximum physiological response to the agriculture inputs that being applied. Production of healthy planting material is initially started from the acquisition of free diseases protocol of seeds from breeder seeds. However, there are still many issues regarding bud-stick in Indonesia which cause the spread of systemic diseases, one of which is CVPD/Huanglongbing (HLB). Therefore, this article presents a descriptive review of the important role of healthy citrus planting materials production that meets the requirements, so that it can become a reference for the citrus nurseries. There are several factors (limited availability of citrus planting materials, technology components to produce healthy seedlings that are not fully applied, as well as the partial application of certified citrus planting materials) that could inhibit the use of technology by the citrus nurseries. A number of recommendations from literatures to overcome these problems are the use of effective dissemination and extension methods, also the provision of understanding and supervision that is carried out on an ongoing basis.

Study on Macro-propagation of Banana cv. Nanjangud Rasabale (AAB) Using Growth Media

Banana is a major food crop globally grown and consumed in more than 100 countries throughout the tropics and subtropics. Banana (Musa paradisiaca.) is the world’s fourth most important food crop after rice, wheat and maize. Banana is usually propagated vegetatively, since sexual reproduction is difficult due to its vegetative parthenocarpic nature. Traditionally, it is been propagated using suckers, as these are easy to obtain. But the factors limiting the adoption of this method are the lower regeneration capacity of sucker, lack of year round availability of mother sucker, fear of transmission of pests and diseases to the succeeding generation. To overcome these issues and to enable the production of a feasible amount of planting material, macro-propagation technology came into existence. Macro-propagation through the use of growth media has accounted lower cost and higher net returns, on an average cost of production of a single plantlet was only Rs. 6.58/-. From the present study, it is inferred that, a feasible amount of healthy and quality planting materials can be produced with minimum expenditure, harnessing good profitability within shorter time span.

Эффективность применения фунгицида «Азорро, КС» при выращивании сеянцев дуба черешчатого в условиях открытого и закрытого грунта

Nowadays the problem of oak forests degradation is topical today in the Republic of Tatarstan, where large woods are formed and are considered to be the most valuable. The area of oak plantations decreases every year due to damage caused by frosts in 1978–1979, therefore, with the oak dying, the areas of aspen, linden and birch plantations increase. The oak forests regeneration is connected with the cultivation of healthy planting material in the nurseries of the region. The article is devoted to the study of the fungicide «Azorro, KS» efficiency in the cultivation of common oak seedlings in open and protected ground conditions. The research was carried out at the experimental site of the Faculty of Forestry and Ecology of the Kazan State Agrarian University. In the course of the research, a phytopathological analysis of acorns was carried out, the degree of infection with pests and diseases, safety by the end of the growing season was determined; biometric indicators of common oak seedlings were measured. The following types of fungi have been found such as Penicillium, Mucor and Rhizopus. The positive effect of the drug used on the growth and development of seedlings in open and protected ground was noted. The highest common oak seedlings were noted in protected ground using a fungicide — 21,0 cm, in open ground the average height was 11,0 cm. The preparation showed its highest efficiency in protected ground — 92 %. High efficiency in the open ground after the third treatment was 90 %. The safety of common oak seedlings by the end of the growing season in protected ground conditions varied from 96,9 to 97,1 %.

Effect of Substrate Type on Survival and Growth of Sweet Potato Vitroplants Under Acclimatization

The lack of healthy planting materials is one of the major constraints of sweet potato cultivation in Benin. One of the solutions to this problem is the use of vegetal biotechnology through micropropagation. At the end of the production of vitroplants, a crucial phase consists in acclimatizing them before their transfer to the real environment. The type of substrate used plays an important role in the success of acclimatization. This study aims at evaluating the effect of the type of substrates on the survival and growth of sweet potato vitroplants in acclimatization of the two accessions (Mèché and Bombo vôvô). For this, three substrates were assessed. These are Potting soil alone, Potting soil + Sawdust, and potting soil + Charcoal powder in proportion 2:1. These substrates were first sterilized separately in an oven at 150°C for 2 hours. The experiment was conducted in the greenhouse of Central Laboratory of Vegetal Biotechnology and Plant Improvement of the Faculty of Sciences and Techniques of the University of Abomey-Calavi following a model of random complete blocks in split plot design. The results show that the type of substrate influences the success of acclimatization in terms of survival rate, the gain of size and the number of neoformed leaves (p= 0.0033; 0.0019 and 0.0001). The Potting soil + Charcoal powder substrate influenced these parameters better than the other two with 95%, 3.13 cm and 3.165 respectively for survival rate, size gain and the number of neoformed leaves. It was followed by the Potting soil + Sawdust substrate. Acclimatized plants have been successfully introduced into the field, proving that this technique is fruitful in the increase of the production of healthy cuttings and make them available to farmers. The protocol used in this study can be applied in the acclimatization of sweet potato vitroplants.

Conservation of grape genetic resources in the system in vitro

Conservation of grape genetic resources in the system in vitro can be a contribution to ampelographic collections, and a source of their replenishment with healthy planting material. The goal of the study is to create a vegetative in vitro collection of plants of promising grape varieties and clones, optimize the conditions for maintaining samples. The basis for obtaining, cultivating, clonal micro-propagating of grape plants is the research and development of the Institute Magarach. At the moment, the collection is represented by 144 samples of grape varieties and clones. Samples of the collection are kept in a state of active growth, slow growth and true dormancy. Previous studies followed to establishment of five modes to maintain grape plants in the system in vitro. Changes in the parameters of individual factors affecting morphogenesis made it possible to slow down growth processes and reduce the number of re-plantings. The most promising mode to conserve samples is the fifth one (this method is patented). As a result of the research carried out in the Institute Magarach, a vegetative collection of plants in vitro of promising grape varieties and clones was created. It includes Crimean autochthonous varieties and varieties of the Institute Magarach breeding. The developed modes of collection conservation allow slowing down growth processes and maintaining plants in a state of true dormancy without re-planting for one to two years.

In vitro Mutations for Biotic and Abiotic Stresses: A Review

Plants are subjected to a wide range of environmental stresses which reduces and limits the productivity of agricultural crops. Two types of environmental stresses are encountered to plants which can be categorized as (1) Abiotic stress and (2) Biotic stress. The abiotic stress causes the loss of major crop plants worldwide and includes radiation, salinity, floods, drought, extremes in temperature, heavy metals, etc. On the other hand, attacks by various pathogens such as fungi, bacteria, oomycetes, nematodes and herbivores are included in biotic stresses. Establishment of a reliable, reproducible and efficient in vitro plant regeneration system with cell and tissue culture is a vital prerequisite for biotechnological application of crop improvement programme. An in vitro plant regeneration technique refers to culturing, cell division, cell multiplication, de-differentiation and differentiation of cells, protoplasts, tissues and organs on defined liquid/solid medium under aseptic and controlled environment. Recent progress in the field of plant tissue culture has made this area one of the most dynamic and promising in experimental biology. There are many published reports on in vitro plant regeneration studies including direct organogenesis, indirect organogenesis and somatic embryogenesis. This review summarizes those plant regeneration studies that could be helpful in drawing the attention of the researchers and scientists to work on it to produce healthy, biotic and abiotic stress resistant plant material and to carry out genetic transformation studies for the production of transgenic plants

Use of prolonged-acting fertilizers in growing garden strawberry seedlings

Timeliness. Currently, the Russian Federation has a high demand in healthy planting material of garden strawberries. The benefits of using fertilizers when growing strawberry seedlings have been proven by numerous studies. However, a comparative study of the effect of new fertilizers and methods of their application is very limited. In this regard, studies aimed at identifying the effectiveness of the use of prolonged-acting fertilizers in the production of garden strawberry planting material in protected soil conditions are relevant.Methods. Adapted to non-sterile conditions, ex vitro healthy garden strawberry plants were planted in a peat substrate of Veltorf LLC (recipe No. 5c/2) with the addition of Pg mix starter fertilizer with the structure NPK 14-16-18 + microelements (1.5 g/l of substrate). At the same time, prolonged-acting fertilizers were introduced into the substrate in the recommended concentrations: FertiPro Gran 1M (1.25 g/l of substrate), Ruscote 5-6M (3.0 g/l of substrate), Basacote Plus 6M (4.0 g/l of substrate), control peat substrate without fertilizers, PG mix standard.Results. It has been established that for the Karmen crop with an average runner-forming ability, the effectiveness of applying FertiPro Gran 1M fertilizer to the substrate was revealed, with the use of which, on the 180th day of cultivation, the number of runners and rosettes increases by 3.5–3.8 times compared to the control. At the same time, the yield of marketable seedlings is 95% compared to 70% in the control. For the Jūnija smaids crop with a high vine-forming ability, the effectiveness of all experimental variants with the application of FertiPro Gran 1M, Ruscote and Basacote Plus fertilizers to the substrate was revealed, with the use of which, on the 180th day of cultivation, the number of runners and rosettes increases by 1,9-2,5 times compared to the control. At the same time, the yield of marketable seedlings is 94-96% compared to 65% in the control.Conclusion. The introduction of long–acting fertilizers FertiPro Gran, Ruscote and Basacote Plus into the peat substrate with the addition of Pg mix starter fertilizer allowed a 2.3 – 3.8-fold increase in the number of runners obtained and 1.9-3.5-fold increase in the number of sockets obtained compared to the control without fertilizers.

PM 7/153 (1) Mechanical inoculation of test plants

PM 7/153 (1) Mechanical inoculation of test plants

Микроклональное размножение и особенности адаптации к условиям ex vitro лесных ягодных растений рода Vaccinium

Modern cost-effective propagation methods yield a large amount of high-quality healthy planting material of economically valuable forest berry plants. However, ex vitro adaptation of Vaccinium species and in vitro cultivation of the Kamchatka bilberry remain understudied. The research objective was to study the effect of growth-regulating substances on the organogenesis and adaptation to non-sterile conditions of the lingonberry and the Kamchatka bilberry during clonal micropropagation. The study featured regenerant lingonberries (Vaccinium vitis-idaea L.) of Koralle, Kostromichka, and Kostromskaya Rozovaya cultivars, as well as the Sakhalin and Kuril varieties of the Kamchatka bilberry (Vaccinium praestans Lamb.). A chemical analysis was performed to reveal the following dependencies: the effect of sterilizing agents and sterilization time on the viability of explants, the effect of the nutrient medium and the growth-regulating substances on microshoots and roots, and the effect of the substrate on the survival of plants in non-sterile conditions. The highest survival rate of lingonberry (72%) and bilberry (96%) explants belonged to 0.2% of AgNO3 with 10 min of sterilization time. The maximal values of the total shoot length in vitro were observed at 0.2 mg/L of 2-iP: AN nutrient medium (7.2 cm) for lingonberries and WPM 1/2 nutrient medium (10.5 cm) for bilberries. The longest total root length in vitro for lingonberries was registered when using 2.0 mg/L (5.8 cm) of indoleacetic acid, while for bilberries it was 1.0 mg/L (1.9 cm) of indolylbutyric acid. The maximal survival rate ex vitro belonged to the high-moor peat substrate (89–92%) for lingonberries and a 1:1 mix of peat with sand (91–95%) for bilb erries. Clonal micropropagation with growth regulators (2-iP, indolylbutyric and indoleacetic acids) and peat substrates proved expedient for in vitro cultivation and ex vitro adaptation of the lingonberry and the Kamchatka bilberry. This scheme delivered a large amount of high-quality planting material with high plant survival.

Анализ роста осины (Populus tremula L.), полученной методом in vitro в условиях Республики Татарстан

The paper presents the results of an experiment on the aspen clones (Populus tremula L.) reproduction resistant to heart rot of the diploid and triploid genotype by micropropagation methods and their introduction into forestry production in the conditions of the Republic of Tatarstan. The expediency of using this method in the conditions of the republic for obtaining healthy planting material of aspen, which is characterized by rapid growth, is substantiated. The prospects of clone No. 35 with a triploid genotype reproduction and its introduction into forestry production in the conditions of the Republic of Tatarstan are shown.

Clonal micropropagation in vitro of essential oil plants of the family Lamiaceae Lindl.

The relevance of research on the development of biotechnology for clonal micropropagation of plants of the family Lamiaceae Lindl. is determined by the need for mass production of healthy, pure-grade planting material for the establishment of industrial plantations and the expansion of areas of essential oil crops in Ukraine. The aim of the research was to develop biotechnological methods of clonal micropropagation of essential oil plants of the Lamiaceae family – Lavandula angustifolia Mill., Mentha x piperita L., Salvia officinalis L. and Monarda fistulosa L. The task of the research was to select optimal conditions for effective cultivation of plants of the Lamiaceae family at four stages of clonal micropropagation. The main methods of research: laboratory, field, analytical, mathematical and statistical. The optimal nutrient media for the induction of in vitro morphogenesis and the multiplication stage were determined based on the basic medium of Murashige and Skoog: for L. angustifolia supplemented with kinetin (1.0 mg/l) and gibberellic acid (1.0 mg/l), for M. x piperita – with 6-benzylaminopurine (1.0 mg/l) and gibberellic acid (0.1 mg/l), for S. officinalis – with 6-benzylaminopurine (1.0 mg/l) and IOLK (0.5 mg/l ), for M. fistulosa – 6-benzylaminopurine (1.0 mg/l) and β-indolyl-3-oleic acid (0.1 mg/l). At the stage of multiplication, it is advisable to carry out seven to eight cycles of cultivation. At the stage of rooting of microshoots, the most effective for all studied plant species was determined to be the Murashige and Skuga nutrient medium with a halved concentration of components, supplemented with β-indolyl-3-oleic acid (0.5 mg/l) and β-indolyl-3-acetic acid ( 0.5 mg/l). The optimal substrate for plant adaptation to in vivo conditions is peat: perlite in a volume ratio of 3:1. Incorporation of the developed biotechnology of clonal micropropagation into the seeding system of essential oil crops of the Lamiaceae family will allow to quickly obtain healthy pure-bred planting material and introduce new productive varieties into production

Improving the efficacy of potato clonal micropropagation by inoculation with the rhizosphere bacteria Azospirillum baldaniorum Sp245 and Ochrobactrum cytisi IPA7.2.

Sustainable development of agriculture depends on the provision of quality seeds to the market. Inoculation with plant-growth-promoting rhizobacteria in in vitro culture can be used to improve the growth eff icacy and performance of microplants. We examined the effect of in vitro inoculation of microplants of the cultivars Nevsky and Kondor with the strains Azospirillum baldaniorum Sp245 and Ochrobactrum cytisi IPA7.2 separately and in combination. We examined the morphological variables of plant growth in in vitro culture and under ex vitro adaptation conditions; we also investigated the growth and performance of the plants in the greenhouse. The dependence of the inoculation eff icacy on potato genotype, growth stage, and inoculum composition was ascertained throughout the experiment. In vitro, A. baldaniorum Sp245 alone and in combination with O. cytisi IPA7.2 promoted the formation of roots on the microplants of both cultivars and the growth of Nevsky shoots. During plant growth ex vitro, all growth variables of the Nevsky microplants were promoted by O. cytisi IPA7.2 alone and in combination with A. baldaniorum Sp245. In both cultivars grown in the greenhouse, shoot growth was promoted in most inoculation treatments. The survival ability of the Nevsky microplants in the greenhouse increased 1.7-fold under the effect of simultaneous inoculation. Inoculation of microplants with a combination of A. baldaniorum Sp245 and O. cytisi IPA7.2 increased the number of Nevsky minitubers 1.5-fold and the number of Kondor minitubers 3.5-fold. Inoculation with the tested strains can be used to promote the growth of microplants and increase the yield of minitubers in potato seed breeding for the production of healthy planting material.

Biology and biotechnological aspect of sweet potato (Ipomoea batatas L.): a commercially important tuber crop

This review highlights the economic importance of sweet potato and discusses new varieties, agronomic and cultivation practices, pest and disease control efforts, plant tissue culture protocols, and unexplored research areas involving this plant. Abstract Sweet potato is widely consumed in many countries around the world, including India, South Africa and China. Due to its valuable nutritional composition and highly beneficial bioactive compounds, sweet potato is considered a major tuber crop in India. Based on the volume of production, this plant ranks seventh in the world among all food crops. Sweet potato is considered a "Superfood" by the 'Centre for Science in the Public Interest' (CSPI), USA. This plant is mostly propagated through vegetative propagation using vine cuttings or tubers. However, this process is costly, labour-intensive, and comparatively slow. Conventional propagation methods are not able to supply sufficient disease-free planting materials to farmers to sustain steady tuber production. Therefore, there is an urgent need to use various biotechnological approaches, such as cell, tissue, and organ culture, for the large-scale production of healthy and disease-free planting material for commercial purposes throughout the year. In the last five decades, a number of tissue culture protocols have been developed for the production of in vitro plants through meristem culture, direct adventitious organogenesis, callus culture and somatic embryogenesis. Moreover, little research has been done on synthetic seed technology for the in vitro conservation and propagation of sweet potato. The current review comprehensively describes the biology, i.e., plant phenotypic description, vegetative growth, agronomy and cultivation, pests and diseases, varieties, and conventional methods of propagation, as well as biotechnological implementation, of this tuber crop. Furthermore, the explored and unexplored areas of research in sweet potato using biotechnological approaches have been reviewed.

Fusarium Dry Rot of Garlic Bulbs Caused by Fusarium proliferatum: A Review

Fusarium dry rot (FDR) is a postharvest disease of garlic crops causing yield losses worldwide. Fusarium proliferatum has been identified as the main species causing the disease. Symptoms begin as small brown lesions with a dehydrated appearance that can progress to cover the entire clove during the storage period. Symptoms on growing plants cause brown lesions on the basal plates and roots, and sometimes damping-off is observed. F. proliferatum is a polyphagous pathogen with a wide range of hosts. This pathogen colonizes garlic roots, remaining as a latent pathogen, and develops rot during storage. The pathogen can overwinter in the soil, infested crop residues, and weeds. The fungus can also persist on garlic cloves, acting as primary inoculum in the field and contributing to the long-distance spread. Using healthy plant material, rotating crops, burying crop residues, avoiding bulb injury during harvest and subsequent handling, and providing appropriate postharvest environmental conditions are crucial factors that greatly influence the disease severity. Choosing a suitable non-host crop to achieve truly effective rotation is sometimes difficult. Chemical control in the form of seed treatments or field spraying of the crop has a limited effect on controlling FDR. Field applications of biological control agents have shown some efficacy, but conditions to optimize their activity must be determined. Moreover, different soil management strategies to reduce soil inoculum must be also studied.