Arbuscular seed viability, and dispersal mechanisms as well

Arbuscular Mycorrhizal Fungi (AMF) is ubiquitous plant root symbionts that can be considered as ‘keystone mutualists’ in terrestrial ecosystem, forming a link between biotic and abiotic ecosystem (O’Neill et al., 1991). These symbiotic associations with roots of the majority of terrestrial plant species (Smith and Read, 2008). However, the plant provides carbohydrates and other nutrients to the fungi. They utilize these carbohydrates for their growth and to synthesize and excrete molecules like glomalin (glycoprotein). The release of glomalin in the soil environment results in better soil structure and higher organic matter content. AMF hyphae are considered to function primarily by increasing the soil volume from which available forms of nutrients are absorbed and provided to roots. Fungal hyphae release enzymes (chitinase, peroxidase, cellulase, and protease), which allows them to digest and penetrate substrates. Secretion of enzymes breaks down tough organic substrates that can then be absorbed and used by the fungus and/or host plant as energy and nutrient sources for growth and reproduction (Kaur et al., 2014). AMF are considered to be ecologically important as they play important roles in the restoration of contaminated ecosystems by improving plant nutrition and fertility of degraded land (Chen et al., 2001). AMF have high drought stress tolerance to environmental conditions, short life cycle, good seed viability, and dispersal mechanisms as well as strong allelopathic effects (Tokarska-Guzik et al., 2012).  Earlier studies indicate the uneven distribution of Glomeromycota among states, climatic zones and ecosystems, and the tendency of fungi with a wide geographical distribution to have a broad host range (Bansal et al. 2012, Lakshmipathi et al. 2012, Sharma and Ya¬dav 2013, Bhattacharya et al. 2013).  AMF species diversity in India is poorly known despite the fact that India is one of the major centres for culture collection and production of large quantity of AMF inocula as biofertilizers and synthetic seeds (Puri and Adholeya 2013, Adholeya et al. 2013). More than 105 Glomeromycota species were known to exist up to 2005 but a systematic re¬cord of occurrence and diversity of AMF in India was not available. They are formed by the group of fungi that are usually present in all soils from the phylum Glomeromycota, including nine genera; Glomus, Paraglomus, Sclerocystis, Acaulosopra, Entrophospora, Gigaspora, Scutellospora, Diversispora and Archaeospora (Schuessler et al., 2001). Distribution and diversity of vesicular arbuscular mycorrhizal fungi have been documented by many workers (Kullu and Behra, 2012; Kavitha and Nelson, 2013; Kirti et al., 2016). The present study is aimed to focus on arbuscular mycorrhizal fungi occurrence, distribution and infectivity in different area of north India viz. Haryana (HR), Jammu and Kashmir (J & K), Himachal Pradesh (HP) and Punjab (PJB). In these areas soil has found different diversity of AMF are abundant but there is not more studied yet now. However, in soil that has been disturbed by different human activity, the quantity of AMF decreases drastically so that there are not enough of them to produce a significant benefit on plant growth and health, hence the importance to compensate this lack. Now days our commercial horticultural and agricultural systems mainly rely on heavy chemical inputs that has not only degraded the soil and environment but also decreased the productivity levels. So, in the current scenario, the most acceptable and environmentally conscious approach to solve this problem is to manipulate the plant rhizosphere population. Keeping this in view, can also be focus on the efficient AMF inoculum for biomass production and growth promotion of different crops.