scholarly journals Efectos De La Fertilización Nitrogenada Y Fosfatada Sobre Poblaciones De Micorrizas Asociadas Al Cultivo De Cacao

2017 ◽  
Vol 13 (6) ◽  
pp. 464
Author(s):  
Wilson Latacela Coello ◽  
Eduardo Colina Navarrete ◽  
Carlos Castro Arteaga ◽  
Danilo Santana Aragone ◽  
Joffre León Paredes ◽  
...  

Cocoa is one of the most significant assets in the ecuadorian agricultural structure, which also provides a good source of income for thousands of farmworker families. However, fertilization research works in cocoa cultivation have been relatively scarce. Decades of global research have shown that mycorrhizal fungi determine the fertilization and conservation of agrosystems. Fertilization is considered to be among the cultural and agricultural practices affecting mycorrhizas, which diminishes or prevents the fungal colonization. The objectives of research works were the following: the characterization of mycorrhiza species associated with cocoa, to determine the effects of nitrogen and phosphate fertilization in plant population and to identify the critical dose affecting the fungus development. A factorial design was used (AxBxC), with two (2) application systems, four (4) doses of nitrogen fertilizer, and two (2) doses of phosphate fertilizer with three repetitions. The turkey’s test was used to evaluate means with confidence interval of 95%. The evaluated variables were: diameter and length of cocoa pods, number of cocoa pods per tree, index of cocoa beans and almond yield per hectare, as well as, mycorrhizal spore counting, percentage of mycorrhizal fungi colonization, visual density of endophyte, and characterization of mycorrhiza species. The results concluded that the application of 100 Kg/ha N + 70 kg/ha P in the system below the soil surface, achieved yield increments of 68% over the absolute witness. The same dose and application method, increased the number of spores per gram of soil, mycelium colonization and density of mycorrhizal endophyte in roots.

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 295
Author(s):  
Marina Moura Morales ◽  
Nicholas Brian Comerford ◽  
Maurel Behling ◽  
Daniel Carneiro de Abreu ◽  
Iraê Amaral Guerrini

The phosphorus (P) chemistry of biochar (BC)-amended soils is poorly understood. This statement is based on the lack of published research attempting a comprehensive characterization of biochar’s influence on P sorption. Therefore, this study addressed the kinetic limitations of these processes. This was accomplished using a fast pyrolysis biochar made from a mix of waste materials applied to a highly weathered Latossolo Vermelho distrofico (Oxisol) from São Paulo, Brazil. Standard method (batch method) was used. The sorption kinetic studies indicated that P sorption in both cases, soil (S) and soil-biochar (SBC), had a relatively fast initial reaction between 0 to 5 min. This may have happened because adding biochar to the soil decreased P sorption capacity compared to the mineral soil alone. Presumably, this is a result of: (i) Inorganic phosphorus desorbed from biochar was resorbed onto the mineral soil; (ii) charcoal particles physically covered P sorption locations on soil; or (iii) the pH increased when BC was added SBC and the soil surface became more negatively charged, thus increasing anion repulsion and decreasing P sorption.


2021 ◽  
Author(s):  
Sally Diatta ◽  
Hassna Mboup-Founoune ◽  
Sidy Diakhaté ◽  
Diégane Diouf

<p>Our planet is marked by significant climatic variations, particularly with the warming of temperatures and the variation in rainfall. In sub-Saharan Africa, the impacts of climate change are more pronounced because agriculture is highly dependent on climate, hence its vulnerability to climate variability (Vanluwe et al., 2011). In the context of changing environmental conditions, the use of innovative agricultural practices to contribute to plant adaptation is necessary to support food security challenges. Agroecological practices to improve crop yields and sustainable soil fertility management. Soil is the main reservoir of biodiversity as it hosts a very high diversity of interacting living species, which can be distinguished according to their size, macrofauna, mesofauna and microorganisms that constitute a particularly important component of soil (Brady and Weil, 2002), particularly for the provision of ecosystem services to humans. This work is therefore interested in studying the contribution of arbuscular mycorrhizal fungi (AMF) to the growth of millet (<em>Pennisetum glaucum</em>) under warmer temperature conditions and the behaviour of microbial community in soil of millet growing.</p><p>Millet is grown in a plant climate chamber and inoculated with a selected mycorrhizal strain.  These millet growing conditions were carried out in two different temperatures: 32°C (normal temperature) and 37°C (warmer temperature).</p><p>The results showed that in conditions of warmer temperature the inoculation induced a significant vegetative growth of millet even with a low intensity of mycorrhization and so it improves microbial nutrient mineralization mediate vegetation growth.</p><p>In soil of millet growing, a significant increase in microbial biomass with 42.7 in warmer temperature condition compared to control temperature 16.7. Results of DGGE shows also a soil abundance and SMB diversity of the total fungal community was noted under warmer temperature condition.</p><p>This study showed that climate variation may affect soil symbiosis but not the potential for promoting plant growth of fungi. The use of arbuscular mycorrhizal fungi on the one hand as a biofertilizer can be an alternative in the context of reducing chemical inputs in agriculture and developing ecologically intensive agriculture (EIA) and on the other hand an adaptive practice  to apprehend the predicted climate changes.</p>


2004 ◽  
Vol 47 (3) ◽  
pp. 381-386 ◽  
Author(s):  
Júlio C. Franchini ◽  
Marcos A. Pavan ◽  
Mário Miyazawa

The objective of this study was to evaluate if cover crops can absorb P from the upper layers and transport it in their roots to subsoil layers. Samples of an Oxisol were placed in PVC columns. Super phosphate fertilizer was applied to the 0-10 cm soil surface layers. The cover crops tested were: Avena strigosa, Avena sativa, Secale cereale, Pisum sativum subsp arvense, Pisum sativum, Vicia villosa, Vicia sativa, Lupinus angustifoliu, Lupinus albus, and Triticum aestivum. After a growth period of 80 days the cover crop shoots were cut off and the soil was divided into 10cm layers and the roots of each layer were washed out. The roots and shoots were analyzed separated for total P contribution to the soil. Considerable amount of P was present in the roots of cover crops. Vicia sativa contained more than 60% of total plant P in the roots. The contribution of Vicia sativa to soil P bellow the fertilized zone was about 7 kg ha-1. It thus appeared that there existed a possibility of P redistribution into the soil under no tillage by using cover crops in rotation with cash crops. Vicia sativa was the most efficient cover crop species as P carrier into the roots from superficial layer to lower layers.


Agronomy ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 127 ◽  
Author(s):  
Arjun Kafle ◽  
Kevin Cope ◽  
Rachel Raths ◽  
Jaya Krishna Yakha ◽  
Senthil Subramanian ◽  
...  

Phosphorus is an essential macronutrient required for plant growth and development. It is central to many biological processes, including nucleic acid synthesis, respiration, and enzymatic activity. However, the strong adsorption of phosphorus by minerals in the soil decreases its availability to plants, thus reducing the productivity of agricultural and forestry ecosystems. This has resulted in a complete dependence on non-renewable chemical fertilizers that are environmentally damaging. Alternative strategies must be identified and implemented to help crops acquire phosphorus more sustainably. In this review, we highlight recent advances in our understanding and utilization of soil microbes to both solubilize inorganic phosphate from insoluble forms and allocate it directly to crop plants. Specifically, we focus on arbuscular mycorrhizal fungi, ectomycorrhizal fungi, and phosphate-solubilizing bacteria. Each of these play a major role in natural and agroecosystems, and their use as bioinoculants is an increasing trend in agricultural practices.


1997 ◽  
Vol 75 (11) ◽  
pp. 1903-1912 ◽  
Author(s):  
Kyeong W. Yun ◽  
M. A. Maun

Greenhouse studies were conducted to test allelopathic effects of Artemisia campestris ssp. caudata on seed germination and seedling growth of several sand-dune species and colonization by mycorrhizal fungi. The aqueous extracts of A. campestris showed no inhibitory effect on seed germination, seedling elongation, or dry-weight growth of plants at lower concentrations (10 and 50%), but 100% concentration of the extracts caused varying degrees of inhibition depending on the test species. The mixing of dry leaves of seedlings of A. campestris to the sand showed severe inhibition of Elymus canadensis seedlings. The percent germination of test species in soil from the rhizosphere of A. campestris was significantly lower than that of the control. The leaf area and dry weight were also lower but the differences were not significant. The aqueous extract inhibited mycorrhizal fungal colonization in roots of three sand-dune grasses. Key words: allelopathy, Artemisia campestris ssp. caudata, seed germination, seedling growth, mycorrhizal fungi.


2017 ◽  
Vol 8 (1) ◽  
pp. 20-25
Author(s):  
Fransisca Yosina Regina Luturmas ◽  
Sri Wilarso Budi R. ◽  
Irdika Mansur

Jabon (Anthocephallus cadamba Roxb.) is one of fast-growing species with high economical value, and well adapted on some of soil types. The aims of this research were to analyze the effectiveness of AMF species isolated from Samama (Anthocephallus macrophyllus (Roxb.) Havil) and to determine the favorable dose of nitrogen and phosphate fertilizer for Jabon growth. The research was conducted CRD-split plot design main plot was Acaulospora sp.1 (M1), Glomus sp.1 (M2), Acaulospora sp.2 (M3), Acaulospora sp.3 (M4), Glomus sp.2 (M5). While the fertilizer as the sub-plot, consist of control (P0), urea 0.5g+rockphosphat 2g (P1), urea 1g+rockphosphat 4g (P2). The result showed that AMF and fertilizer applications effectively improved Jabon grown, especially in height, stem diameter, and shoot dry weight. The interaction (M4P1) increased plant height 154.73%, diameter 75.38% and shoot dry weight 376.09% compared with control. P1 treatment was better for growth of Jabon that was inoculated by mycorrhiza. Acaulospora sp.1 (M1) originally from Samama without fertilizer had the best effectiveness for Jabon growth.Key words: Acaulospora, indigenous


2006 ◽  
Vol 05 (3) ◽  
pp. 8-20
Author(s):  
José Carlos Oliveira SANTOS ◽  
Lionete Dantas NUNES ◽  
Sylvia Berenice NÓBREGA ◽  
Dantas José Pires PUZINSKI ◽  
Antonio Gouveia SOUZA

A thermal analysis has been applied to characterization of food and food products. Taking into account the problems of desertification and agricultural practices able to provide income to the population at the semi-arid region of Northeastern Brazil, this work presents the results of the chemical, thermal and kinetic characterization by thermogravimetry and differential scanning calorimetry of the seed derivatives of favelone (cnidoscolus quercifolius), aiming at the application of these materials as an alternative of food source for animals and for the human population at this brazilian region.


2016 ◽  
Vol 40 (3) ◽  
pp. 203 ◽  
Author(s):  
Bambang Suwignyo ◽  
Bela Putra ◽  
Nafiatul Umami ◽  
Cahyo Wulandari ◽  
Ristianto Utomo

This study aimed to determine the effect of arbuscular mycorrhizal fungi (AMF) and phosphate (P) fertilizer on the nutrient content, phosphate uptake and in vitro digestibility of alfalfa (Medicago sativa L.).The research was conducted at green house of Forage and Pastures Science Laboratory, Faculty of Animal Science Universitas Gadjah Mada. The experiment was arranged in Completely Randomized Design using 3x4 factorial patterns with four replications. The first factor was dosage of phosphate fertilizer SP 36 (0, 60, and 120 kg/ha). Second factor was the dosage of AMF (0, 0.8, 1.6, and 2.4kg/ha). The variable measured was nutrient contents (crude protein, dry matter, and organic matter), total P uptake and dry matter and organic matter in vitro digestibility. The results showed that the interaction of AMF and P fertilizer had no significant effect on crude protein and total P uptake, but highly significant effect on the parameters of dry matter, organic matter and dry matter and organic matter in vitro digestibility. 


2021 ◽  
Vol 12 ◽  
Author(s):  
Ricardo Alexander Peña Venegas ◽  
Soon-Jae Lee ◽  
Moses Thuita ◽  
Deusdedit Peter Mlay ◽  
Cargele Masso ◽  
...  

A vast majority of terrestrial plants are dependent on arbuscular mycorrhizal fungi (AMF) for their nutrient acquisition. AMF act as an extension of the root system helping phosphate uptake. In agriculture, harnessing the symbiosis can potentially increase plant growth. Application of the AMF Rhizophagus irregularis has been demonstrated to increase the yields of various crops. However, there is a paradigm that AMF colonization of roots, as well as the plant benefits afforded by inoculation with AMF, decreases with increasing phosphorus (P) supply in the soil. The paradigm suggests that when fertilized with sufficient P, inoculation of crops would not be beneficial. However, the majority of experiments demonstrating the paradigm were conducted in sterile conditions without a background AMF or soil microbial community. Interestingly, intraspecific variation in R. irregularis can greatly alter the yield of cassava even at a full application of the recommended P dose. Cassava is a globally important crop, feeding 800 million people worldwide, and a crop that is highly dependent on AMF for P uptake. In this study, field trials were conducted at three locations in Kenya and Tanzania using different AMF and cassava varieties under different P fertilization levels to test if the paradigm occurs in tropical field conditions. We found that AMF colonization and inoculation responsiveness of cassava does not always decrease with an increased P supply as expected by the paradigm. The obtained results demonstrate that maximizing the inoculation responsiveness of cassava is not necessarily only in conditions of low P availability, but that this is dependent on cassava and fungal genotypes. Thus, the modeling of plant symbiosis with AMF under different P levels in nature should be considered with caution.


2021 ◽  
Vol 22 (11) ◽  
Author(s):  
Maria Viva Rini ◽  
Fitri Yelli ◽  
Darwin Leonardo Tambunan ◽  
Inggar Damayanti

Abstract. Rini MV, Yelli F, Tambunan DL, Damayanti I. 2021. Morphological and molecular identifications of three native arbuscular mycorrhizal fungi isolated from the rhizosphere of Elaeis guineensis and Jatropha curcas in Indonesia. Biodiversitas 22: 4940-4947. Molecular analysis has been widely used to provide more accurate identification within arbuscular mycorrhizal fungi (AMF) species than identification based on morphology. However, morphological analysis is essential for a basic preliminary of classification studies. Therefore, a study is needed to complete the identification of AMF isolates through morphological and molecular analyses. This research used three AMF isolates, namely MV 5, MV 17, and MV 18, which were isolated from Indonesian agricultural land. Spore-based taxonomy (shape, size, color, ornamentation, PVLG, and Melzer’s reaction) and fungal colonization on roots of maize trap plants were employed for the morphological studies. AMF species identification was performed using molecular analysis through nested-Polymerase Chain Reaction (PCR) to amplify a fragment of SSU rRNA followed by sequencing and phylogenetic tree construction. Morphological analysis showed that MV 5 had spores borne from the neck of the sporiferous saccule, MV 17 was found to have a bulbous suspensor without a germination shield, and MV 18 had spores borne from subtending hyphae. The SSUR rRNA analysis revealed that MV 5, MV 15, and MV 18 were identified as Acaulospora longula, Gigaspora margarita, and Glomus etunicatum, respectively. Both morphological and molecular methods demonstrated reliable and consistent results that complement AMF taxonomy studies.


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