Vesicular-arbuscular Mycorrhizal Research Articles

Root colonization by vesicular arbuscular mycorrhizal in different dosage forms and effect on C3 plants root morphology

The application of vesicular arbuscular mycorrhizal (VAM) in powder dosage form has been used for a long time. However, this dosage form has a non-uniform application dose and allows VAM spores to be lost through wind and rainwater, so innovation is needed in the VAM dosage form. A study aimed at knowing dosage forms of VAM as a biological agent that affects colonization level and C3 plant‘s root morphology was carried out at Screen House Laboratory, Faculty of Agriculture, Animal Husbandry and Fisheries, University of Muhammadiyah Parepare using a factorial design based on completely randomized design (CRD). Treatment of VAM dosage forms (factor 1) used was powder (A1), sachet (A2), and tablet (A3). While the C3 plant species (factor 2) used were Puraria japonica (B1), Vigna radiata (B2), and Amaranthus gangeticus (B3). Observations were conducted on the percentage of colonized roots and the C3 plants’ root morphology. The results showed that the combined treatment of VAM dosage forms (powder, sachet, and tablets) and C3 plant species (Puraria javanica, Vigna radiata, Amaranthus gangeticus) showed significant effects on colonized roots percentage and C3 plant root morphology. So it can be recommended that VAM dosage forms (sachet and tablet) are efficient and effective for the mobilization and field application of VAM.

Vesicular arbuscular mycorrhizal influence on growth of cancer bush (Sutherlandia frutescens) and alleviation of saline stress

Lack of arable land on a global scale, agricultural malpractices and high soil salinity have prompted the development of alternative eco-friendly ways to increase crop production. The usage of vesicular arbuscular mycorrhizal (VAM) has been reported to positively improve crop production under harsh soil conditions but no such effort has fixated on traditional underutilized crops such as cancer bush (Sutherlandia frutescens). Given its significance as a versatile remedial crop, it is critical to cultivate this plant and regulate the agronomic necessities for its effective cultivation. Therefore, two separate experiments were conducted at the University of Mpumalanga, Mbombela, South Africa in 2021 and 2022, with an objective to investigate whether VAM will improve growth of cancer bush under saline soil conditions. Three weeks old cancer bush seedlings were planted in pots under microplot conditions. The in a 4 x 4 factorial treatmentarrangement in a randomized complete block design. The seedlings were grown in four geometric series of NaCl : CaCl2 (3 : 1) of artificial chloride salinity levels: 0, 0.25, 0.5 and 0.75 ds/m and four levels of VAM: 0,10, 20, and 30 g/pot, with four replications in the two successive years. At 60 days after initiation of treatments, dry root mass and number of branches were significantly affected by treatments in Experiment 1, with total treatment variation (TTV) of 11-17 and 9-34%, respectively of the variables. Dry shoot mass was significantly affected by treatments in Experiment 2, with TTV of 26-32%. In both the experiments, treatments had significant effects on soil EC, contributing 26-42% in TTV in Experiment 1, whereas in Experiment 2 the treatments contributed 4-76% in TTV of the respective variable. In conclusion, findings in the current study demonstrated that VAM in presence of salinity improved growth relative to plants under saline stress.

Investigation of possible vesicular arbuscular mycorrhizal associations in prevalent weeds in tea lands of Badulla

A study was carried out to investigate the possible vesicular arbuscular mycorrhizal (VAM) associations in prevalent weeds in selected tea lands of Badulla. Roots of Ageratum conyzoides, Axonopus compressus, Bidens pilosa, Borreria latifolia, Cleome rutidosperma, Drymaria cordata, Eleusine indica, Erigeron sumatrensis and Oxalis corniculata were collected from Wewessa, Spring Valley and Telbedde estates. Colonization percentages and spore counts were calculated using the Grid and Doncaster’s counting disc methods, respectively. Rhizosphere soil of highly VAM associated weeds were tested for soil phosphorous and all weeds were tested for soil pH. The highest colonization percentage was recorded as 60.39% with A. compressus. The highest spore number was counted as 187 per 5 g soil with B. latifolia. The lowest soil phosphorus level was measured as 4.17 ppm with A. conyzoides. There was a systematic moderate positive correlation between, root colonization percentages and soil pH. In conclusion, there was a close association of VAM with selected nine weed species.

Increasing photosynthetic productivity of cereal bioenergy crops as affected by the water content in leaves under mycorrhization of the root system

Purpose. To determine photosynthetic productivity of miscanthus gigantheus and switchgrass as affected by leaf water content under mycorrhization of their roots.
 Methods. Field, laboratory, and statistical.
 Results. The obtained results indicate that the use of vesicular-arbuscular mycorrhizal (VAM) preparations Mycofriend (fungus Trichoderma harzianum RIFAI.), Mikovital (fungus Tuber melanosporum VITTAD.), and nitrogen-fixing preparation Florobacillin (Bacillus subtilis Cohn.) helps to increase water content in the leaves of such cereal bioenergy crops as miscanthus gigantheus and switchgrass. In particular, in all vegetation periods, in the treatments with Mycofriend, the water content in miscanthus gigantheus leaves was higher by 11.2–20.1% than in the control, while in switchgrass it was higher by 16.9–20.5% than in the control. In the treatments with Mikovital and Florobacillin, leaf water content ranged in miscanthus from 7.1 to 15.6% and from 5.8 to 11.7%, respectively, and in switchgrass, from 11.6 to 14.7% and from 7.0 to 10.2%, respectively. The photosynthetic productivity of these crops is affected by the water content in the leaves. There is a close correlation between these factors (correlation coefficient 0.95–0.96).
 Conclusions. Root application of biological plant products Mycofriend, Mikovital and Florobacillin improves water content in the leaves of cereal bioenergy crops, such as miscanthus gigantheus and switchgrass, and increases their photosynthetic productivity.

ПІДВИЩЕННЯ ПРОДУКТИВНОСТІ ФОТОСИНТЕЗУ СІЛЬСЬКОГОСПОДАРСЬКИХ КУЛЬТУР ЗАЛЕЖНО ВІД ОБВОДНЕНОСТІ ЇХ ЛИСТКІВ ЗА МІКОРИЗАЦІЇ КОРЕНЕВОЇ СИСТЕМИ

Purpose. To investigate the effect of pre-sowing seed treatment with vesicular-arbuscular mycorrhizal (VAM) and bacterial preparations on the leaf water content and photosynthetic productivity of agricultural crops (winter wheat, corn, sunflower and soybean) under mycorrhization of their roots. Methods. Field, laboratory, and statistical. Results. The results of studies on determining the effect of pre-sowing treatment of seeds of such agricultural crops as soft winter wheat, common corn, annual sunflower and soybean culturally vesucular-arboscular drugs Mikovital (mushroom Tuber melanosporum VITTAD.) Micofrend (mushroom Trichoderma harzianum. (bacteria Bacillus subtilis Cohn.) on the water content of leaves and the productivity of photosynthesis of plants by mycorrhization of their root system. It was found that the implementation of this measure provides a steady increase in the water content of leaves and the productivity of photosynthesis of agricultural crops. In particular, the water content of leaves of soft winter wheat plants, common corn, annual sunflower and cultivated soybeans for the use of the preparations Mikovital, Mikofrend and Florobatsilin was 1.6–77.3 % more than in the control. According to the indicators of the water content of the leaves, the productivity of photosynthesis of crops increased by 8.3–57.1 % in comparison with the control, which indicates a significant effect of this factor on the growth and development of plants. Conclusions. Pre-sowing seed treatment with vesicular-arbuscular products Mikovital, Mycofrend, and bacterial product Florabacillin promotes a steady increase in the leaf water content and photosynthetic productivity in winter bread wheat, maize, annual sunflower, and soybean.

A Study on Root Colonization of Medicinal Plants with Vesicular Arbuscular Mycorrhizal Fungi

Abstract The present study deals with the root colonization of medicinal plants with vesicular-arbuscular mycorrhizal (VAM) fungi. Mycorrhiza is defined as a mutualistic association between the fungi and plant roots. The plant materials used for the study were collected from the premises of St. Dominic’s College, Kanjirappally, Kottayam district of Kerala. The collected specimens were chemically treated and observed under microscope. The result of the study confirmed that the VAM fungi produce various structures within the roots. It was also noted that the root colonization percentage varied between 50 and 80% within the selected plants. Keywords: Vesicular arbuscular mycorrhizal fungi, root colonization, arbuscules, vesicles Cite this Article Nooruddeen Jabbar, Sallykutty Thomas. A Study on Root Colonization of Medicinal Plants with Vesicular Arbuscular Mycorrhizal Fungi. Research & Reviews: Journal of Botany . 2020; 9(1): 1–8p.

Potential of Sunflower to Extract Heavy Metals from Leachate

The effectiveness of sunflower to extract harmful heavy metals from landfill leachate using phytoremediation technique was studied in this paper. A case study of Phursungi garbage dump yard located in Phursungi village in Pune, India was taken for this study as the residents have to deal with contaminated water throughout the year which induces diseases like dysentery, cholera, hepatitis, and heavy metal poisoning related diseases. There are various methods in phytoremediation, among which phytoextraction was used for this study. An experiment was carried out to test the removal efficiency of BOD, COD, TS, and heavy metals namely As, Hg and Pb from the soil by sunflowers with and without the addition of Vesicular Arbuscular Mycorrhizal (VAM) fungi. These fungi were used in soil to accelerate the process of extraction. Leachate diluted with 60% water was supplied such that the Hydraulic Retention Time (HRT) was more than 15 days (19 days achieved). The values of contaminants were checked for permissible limits according to standards for land disposal of treated leachates given in Municipal Solid Waste Management (MSW) rules, 2016 and Central Pollution Control Board (CPCB), India. The removal efficiency of Pb from soil was almost the same for plants supplied with VAM (67.92%) and plants without VAM (66.67%). Arsenic (As) removal efficiency was 100% for plants with and without VAM. For mercury (Hg), it was more for plants without VAM (96.29%) than plants with VAM (77.78). Thus, it was concluded that VAM was ineffective. Cd and Cr concentrations in leachate samples were observed to be within the permissible limits. Hence, they were discarded for calculation of removal efficiency.

Jamur Mikoriza Vesikular Arbuskular (MVA) Pada Tiga Jenis Tanah Rhizosfer Tumbuhan Lakum (Cayratia trifolia (L.) Domin)

The lakum plant (Cayratia trifolia (L.) Domin) is a wild plant so it is easily found in various types of soil, such as alluvial soil, ultisol soil and soil with salinity (saline soil). The ability of the lakum plant (C. trifolia) to grow on alluvial soil, ultisol soil, and saline soils is presumably cause by a role of Vesicular Arbuscular Mycorrhizal (VAM) fungi. This research aims to find out about VAM fungi in the rhizosphere of the lakum plant (C. trifolia) and the rate of VAM fungal infection in three types of rhizosphere soil of the lakum plant. This research was conducted for three months, starting from January to May 2018 at the Microbiology Laboratory of the Faculty of Mathematics and Natural Sciences of Tanjungpura University. The research procedure included several stages, namely sampling, isolation of spores by a combination of wet filter pouring technique, identification and characterization, and coloring and making root preparations with coloring method. Based on the results of the research, the spores of the VAM fungi found in alluvial soil consisted of the genera Acaulospora, Archaeospora, Glomus and Paraglomus. The spores of the genus of VAM fungi found on the saline soil were only the genus Glomus. The spores of the genus of VAM fungi found on ultisol soil consisted of the genera Acaulospora, Glomus and Paraglomus. The results of observations show that VAM fungal infection in alluvial soil was 25% (low), in saline soil 50.6% (high) and ultisol soil 53% (high)

Pengaruh Level Penggunaan Jamur Mikoriza Terhadap Komposisi Nutrisi Hijauan Sorgum Sebagai Pakan

The study aimed to evaluate the nutrient composition of sorghum forage with the addition of vesicular-arbuscular mycorrhizal fungi (VAM) was conducted for 5 months  from June to November 2016. Sorghum is grown in polybags and placed on the forage land of the State Agricultural Polytechnic of Kupang. This study was conducted using a completely randomized design with 4 treatments and 5 replications, The treatment were: without mycorrhizal fungi (S0), mycorrhizal fungi 5 gram/polybag (S5), mycorrhizal fungus 10 gram/polybag (S10) and mycorrhizal fungus 15 gram/polybag. The measured variables were dry matter (DM) content, ash content, crude protein (CP) content, ether extract (EE) content, crude fiber (CF) content and nitrogen free ekstract (NFE) content. The data were analyzed by analysis of variance and followed by Duncan's multiple-range test. The results showed that the level of mycorrhizal fungi use only significant (P<0.05) to the ether extract (EE) content, crude fiber (CF) content and nitrogen free ekstract (NFE) content, while the content of dry matter (DM), ash content and crude protein (CP) content No significant effect (P> 0.05). The Average dry matter content 16,27%; ash content of 11.03%; crude protein content of 10.12%; ether extract content 2.94%; crude fiber content 22.61% and NFE content 53.30%. Keywords : sorghum forage, vesicular-arbuscular mycorrhizal (VAM) level, nutrient composition.

Vesicular Arbuscular Mycorrhizal (VAM) fungi- as a major biocontrol agent in modern sustainable agriculture system

In the present agricultural system, the discriminate use of synthetic chemical fertilizers has predominantly increased throughout the world. Moreover, using excessive use of fertilizers to increase production deteriorates the various soil qualities and pollute water body environment. So using VAM fungi as a biocontrol agent in modern sustainable agriculture, in terms of various parameters like reduction of damage caused by various pathogens, cost effectiveness, energy saving and also as an environment friendly, is a promising perspective in modern agriculture. Also control of plant pathogens in modern agriculture is presently accepted as a key practice in sustainable agriculture because it is based on the management of certain rhizosphere organisms, common components of ecosystems, known to develop antagonistic activities against harmful organisms. Vesicular Arbuscular Mycorrhizal Fungi interact with other microorganisms in the rhizosphere and various other soil constituents. Upon root colonization by VAMF, there occurs profound physiological changes in the host plant. Present agriculture system increasing demand for low-input agriculture and creates greater interest in soil microorganisms which are able to accelerate plant nutrition, health and improve soil quality. The importance of VAM in incresaing food production is far and wide; therefore these can be used in modern sustainable agriculture particulary as biocontrol agent. This review highlights the different interactions of Vesicular Arbuscular Mycorrhizal Fungi (VAMF) and the rule of these interactions in the biological control of plant pathogens. But the commercial use of Vesicular Arbuscular Mycorrhizal Fungi (VAMF) as biocontrol agents is still in its infancy. The main reason is the poor understanding of the mechanisms of the modes of action of VAM fungi in association with the host plants.

Pigeon Pea and Cowpea-Based Cropping Systems Improve Vesicular Arbuscular Mycorrhizal Fungal Colonisation of Subsequent Maize on the Alfisols in Central Malawi.

Mycorrhizal associations contribute to the sustainability of crop production systems through their roles in nutrient cycling and other benefits in the soil-plant ecosystems. A two-year study was conducted on the Alfisols of Lilongwe and Dowa districts, Central Malawi, to assess the vesicular-arbuscular mycorrhizal (VAM) fungal colonisation levels in pigeon pea, cowpea, and maize grown in sole cropping, legume-cereal, and legume-legume intercropping systems and in the maize grown in short rotation (year 2) as influenced by the previous cropping systems and N fertilizer application. The gridline intersect method was used to assess the VAM fungal colonisation levels. Results showed that all treatments that included legumes whether grown as sole crop, in legume-cereal or in legume-legume cropping systems in the previous year, had significantly higher (P < 0.05) VAM fungal colonisation of the rotational maize crop roots by a range 39% to 50% and 19% to 47% than those in maize supplied and not supplied with N fertilizer, respectively, in a maize-maize short rotation, at the Lilongwe site. A similar trend was reported for the Dowa site. Furthermore, there were positive correlations between VAM fungal colonisation and the plant P content, dry matter yield, and nodule numbers. Further studies may help to assess the diversity of VAM fungal species in Malawi soils and identify more adaptive ones for inoculation studies.

Microsymbiont enhances survival of teak seedlings and nutrient status of soils under saline soils

Seedlings of teak were planted under different salinity levels viz ., normal soil (<4 ECe soil), saline soil (4-8 Ece) and highly saline soil (8-12 ECe) and seedlings were inoculated with Azetobactor + vesicular-arbuscular mycorrhizal (VAM) fungi, Azospirillium + vesiculararbuscular mycorrhizal (VAM) fungi and combination of all three. Experiment repeated for two years and data recorded at the end of each experiment on nutrient satus of soil pH, ECe N, P, K, Ca, Mg, Na, micronutrient (Fe, Zn, Mn and Cu) and survival per cent of seedlings. Triple inoculation ( Azetobactor+Azospirillium +VAM) significantly influenced on the nutrient status of soil and survival per cent of teak seedlings as compared to uninoculated seedlings under salt condition. Which was followed by dual inoculation of Azospirillium and VAM.

Response of weeds and soil microorganisms to imazaquin and pendimethalin in cowpea and soybean

Herbicides applied to combat weeds and increase crop yields may also have undesired effects on beneficial soil microorganisms. Field studies were conducted in 2005 and 2006 in Zaria, Nigeria, to evaluate the response of weeds and soil microorganisms to imazaquin applied at 0.05, 0.10, 0.20 and 0.40 kg a.i./ha and pendimethalin applied at 1.0, 2.0, 4.0, and 8.0 kg a.i./ha in cowpea and soybean. Hoe-weeded and unweeded (no herbicide) plots were controls. Both herbicides significantly reduced weed biomass in both crops, when compared to the unweeded control, which had the highest weed biomass at all sampling dates. Treatments with 0.40 kg a.i./ha of imazaquin, 2.0 and 4.0 kg a.i./ha of pendimethalin, and the hoe-weeded control, had the highest cowpea grain yield. The unweeded control had the lowest grain yield which was comparable to that in all other herbicide treatments. All treatments except 4.0 and 8.0 kg a.i./ha of pendimethalin had higher soybean grain yield than the unweeded control. Soybean yield was lowest in the unweeded control, and treatments that received 4.0 and 8.0 kg a.i./ha of pendimethalin. All rates of imazaquin gave similar soybean grain yields that were 29–41% higher than that from pendimethalin. The hoe-weeded control had the highest yield, which was 79% more than that in the unweeded control. Higher rates of imazaquin and pendimethalin reduced nodulation, nitrogen fixation, and vesicular arbuscular mycorrhizal (VAM) fungi colonisation in both crops. VAM fungi species diversity and species richness in cowpea rhizosphere soil and species diversity in soybean rhizosphere soil were reduced relative to the controls due to application of both herbicides with the rates of 0.10, 0.20, and 0.40 kg a.i./ha of imazaquin and 8.0 kg a.i./ha of pendimethalin being significantly effective.

Influence of Inorganic Phosphorus, VAM Fungi, and Irrigation Regimes on Crop Productivity and Phosphorus Transformations in Okra (Abelmoschus esculentus L.)–Pea (Pisum sativum L.) Cropping System in an Acid Alfisol

The present investigation was carried out at CSK Himachal Pradesh Agricultural University, Palampur, India, during 2009–2011 to economize inorganic phosphorus (P) and water needs of an okra (Abelmoschus esculentus)–pea (Pisum sativum) cropping system through vesicular arbuscular mycorrhizal (VAM) fungi (Glomus mosseae) in a Himalayan acid Alfisol. The field experiment was replicated three times in a randomized block design comprising 14 treatments consisting of 12 treatment combinations of two VAM levels [0 and 12 kg ha−1], three phosphorus levels [50, 75, and 100% of recommended soil-test-based nitrogen (N)–P–potassium (K)], and two irrigation regimes [40 and 80% of available water-holding capacity of field soil (AWC)], in addition to one treatment with “generalized recommended NPK dose with generalized recommended irrigations (GRD)” and one treatment based on “farmers’ practice of plant nutrition and irrigation management in the region.” This article presents crop productivity and P dynamics studies during the second crop cycle of okra–pea sequence (2010–2011) and statuses of different P fractions in the soil after the second pea crop harvest during 2010–2011. Crop productivity and P uptake data in okra–pea sequence indicated that application of VAM + 75% P dose at either of two irrigation regimes did not differ significantly than GRD treatment and VAM + 100% P dose. It suggests an economy of about 25% inorganic P dose through VAM fungi. The treatments imbedded with VAM inoculation enhanced the P uptake in okra–pea system, on an average by 21% over the GRD and non-VAM-inoculated counterparts. Further, integrated application of P, VAM, and irrigation regimes evaluated in okra–pea sequence for 2 years led to greater status of water-soluble P (21%), sodium bicarbonate (NaHCO3)–inorganic phosphorus (Pi) (11%), sodium hydroxide (NaOH)–Pi (9%), hydrochloric acid (HCl)–extractable–P (20%) over non-VAM-inoculated counterparts and low status of organic P (NaHCO3-Po and NaOH-Po), all of which appreciably contributed to available P supply to plants in the present study in an acid Alfisol. The correlation coefficient reveals that contribution of inorganic P forms is highly correlated to crop productivity and total P uptake in okra and pea crops besides soil available P in the present study. Overall, it is concluded that VAM inoculation in okra–pea cropping system significantly enhanced the P availability to plants by way of enriching the labile-P pool such as water-soluble P and P loosely bound to aluminium (Al-P) and iron (Fe-P) on adsorption complexes and by P mineralization from organic matter in an Himalayan acid Alfisol.

Comparative Performance of Geographical Isolates of Glomus mosseae in Field Crops under Low-Input Intensive P-Deficient Acid Alfisol

Comparative performance of five geographical isolates of Glomus mosseae screened from maize fields, soybean fields, vegetable fields, tea orchard, and citrus orchard was assessed in three major field crops (wheat, maize, and soybean) under low-input management in three glass-house pot experiments in a phosphorus (P)–deficient acid Alfisol. These geographical isolates of Glomus mosseae varied with respect to vesicular arbuscular mycorrhizal (VAM) spore count and root colonization in these crops with greatest spore count (240 per 250 g soil) and root colonization (28–34%) using previously screened local Glomus mosseae culture (VAML) of CSK Himachal Pradesh Agricultural University, Palampur, India, followed in order by VAM isolate from vegetable-based cropping system, Glomus mosseae isolate from soybean fields, and Glomus mosseae isolate from tea farm. Glomus mosseae isolate from vegetable-based cropping system remaining at par with local VAM culture (VAML), resulting in significantly greatest grain productivity in these field crops under low-input management. There was a considerable reduction in soil fertility with respect to NPK status over the control and initial status in pot soils inoculated with Glomus mosseae isolate from vegetable-based cropping system followed by local VAM strain (VAML), thereby indicating greater nutrient mobilization and productivity as well through this efficient Glomus mosseae strain in P-deficient acid Alfisol. In addition, Glomus mosseae isolates from different farming situations resulted in differential productivity and soil fertility under these field crops. Overall, Glomus mosseae isolate from vegetable-based cropping system proved its superiority in realizing greater productivity and nutrient mobilization compared to local Glomus mosseae VAM culture under low-input management in P-deficient acid Alfisol.

Effect of Vesicular Arbuscular–Mycorrhizal Fungi and Phosphorus Application through Soil-Test Crop Response Precision Model on Crop Productivity, Nutrient Dynamics, and Soil Fertility in Soybean–Wheat–Soybean Crop Sequence in an Acidic Alfisol

A field experiment was conducted in a phosphorus (P)–deficient acidic alfisol of the northwestern Himalayas using three vesicular arbuscular mycorrhizal (VAM) cultures: a local culture developed by CSK Himachal Pradesh Agricultural University, Palampur (Glomus mosseae), VAM culture from Indian Agricultural Research Institute (IARI), New Delhi (Glomus mosseae), and a culture from the Centre for Mycorrhizal Research, The Energy Research Institute (TERI), New Delhi (Glomus intraradices). These were applied alone or in combination with 25 to 75% of recommended P2O5 and recommended nitrogen (N) and potassium (K) based on soil-test crop response (STCR) precision model with an absolute control, farmers’ practice, and 100% of recommended P2O5 dose based on the STCR model. The results revealed that sole application of either of the three VAM cultures have produced 2.68 to 9.81% and 25.06 to 28.62% greater grain yield than the control in soybean and wheat crops, respectively. Besides greater straw yield, NPK uptake as well as soil nutrient buildup increased. Increase in P fertilization from 25 to 75% of recommended P2O5 dose coupled with VAM inoculation with either of the three VAM cultures resulted in consistent and significant improvement in crop productivity (grain and straw yields), NPK uptake, and improved soil nutrient status, though significantly greatest magnitude was obtained with sole application of 100% of the recommended P2O5 dose. The targeted grain yields of soybean (25 q ha−1) and wheat (30 q ha−1) were achievable with 75% of recommended P2O5 dose along with mycorrhizal biofertilizers, thereby indicating that application of efficient VAM fungi with 75% of recommended P2O5 dose can economize the STCR precision model fertilizer P dose by about 25% without impairing crop yield targets or soil fertility in a soybean-based cropping system in an acidic alfisol.

Role of Endomycorrhizae on Controlling Stem- and Root-Rot of Pepper Caused by Sclerotium rolfsii

This study was designed to investigate the effect of inoculation time with vesicular arbuscular mycorrhizal (VAM) fungi, Glomus spp., on the interaction between root-rot and stem-rot of pepper caused by Sclerotium rolfsii Sacc. as well as its growth. The results indicated that addition of Glomus spp. significantly increased the shoot and root fresh and dry weight with significant decrease to the disease severity (59-89%). Effect of the mycorrhizal inoculation using five species of Glomus by two different inoculation treatments on incidence of Sclerotium stem-rot as well as crop parameters of pepper plants inoculated with the tested fungus was investigated. Generally, mycorrhizal inoculation increased pepper shoot and root fresh and dry weight compared with uninoculated plants. Meanwhile, seedlings arose from seeds treated with Glomus spp. increased growth parameters and yield. G. coronatum and G. luteum were the best mycorrhizae to increase crop parameters. On the other hand, G. etunicatum, G. diaphanum and G. luteum were the best to protect pepper plants against S. rolfsii.

Relative effectiveness of indigenous populations of vesicular-arbuscular mycorrhizal fungi from four sites in the Negev

ABSTRACT Vesicular-arbuscular mycorrhizal (VAM) fungi indigenous in the soil of the semi arid northern Negev of Israel greatly enhanced phosphorus (P) uptake of mycorrhizal pepper plants in three out of four soils tested and at four P levels. In a calcareous loess soil, additions of superphosphate equivalent to 3,000 kg ha−1 could not alleviate the absence of the VAM association. Increasing internal leaf P levels were correlated closely with a stimulation of flower bud production in pepper. Subsequent planting of onion in the same soils with no further P addition revealed the total dependency of this species on the VAM symbiosis. Mycorrhizal infection reduced by half the R/S ratios of onion plants, mainly by the enhancement of shoot growth. Results indicate the presence of a highly efficient VAM population in the loess soil. These findings are considered with regard to the evolution of the mycorrhizal association and its effect on plant morphology and physiological processes.

Improving Phosphorus Use through Co-inoculation of Vesicular Arbuscular Mycorrhizal Fungi and Phosphate-Solubilizing Bacteria in Maize in an Acidic Alfisol

Performance of three vesicular arbuscular mycorrhizal (VAM) fungi cultures and a phosphate-solubilizing bacteria (PSB) culture alone or in combination with or without 75% of the recommended P2O5 dose based on soil-test crop response model was examined in maize in a phosphorus (P)-deficient acidic Alfisol in a glasshouse pot experiment. Sole application of VAM besides co-inoculation with PSB (Pseudomonas striata) and inorganic P stimulated mycorrhizal root colonization. Sole application of PSB, VAMT (Glomus intraradices), and VAMI (Glomus mosseae) as well as co-inoculation of VAM with PSB significantly improved crop productivity besides grain protein content, thus indicating a synergistic interaction between VAM and PSB. Application of VAMT or VAMI + PSB + 75% P2O5 remained at par with sole application of 100% P2O5 dose with regard to productivity, nutrient uptake, and soil fertility status (particularly P), thus indicating economization of fertilizer P to the tune of about 25% without compromising crop productivity and soil fertility in an acidic Alfisol.

English

The objective of the present study is to find out the effect of&nbsp;Arbuscular mycorrhiza(AM) fungal inoculation on growth, productivity and nutrient uptake in two cowpea (Vigna unguiculata) varieties. The AM inoculated plants out performed than non-inoculated plants (control) in terms of growth, productivity parameters and nutrient uptake. AM fungal inoculation had a significant effect on productivity of cowpea attributed to growth, plant height, number of nodules, mycorrhizal dependency and number of flowers&nbsp;per plant. &nbsp; Key words:&nbsp;Vesicular-arbuscular mycorrhizal (VAM), cowpea, nutrient uptake, mycorrhizal dependency (MD).