Organic Seed Treatment with Seaweed Nano Powders on Physiological Quality and Enzyme Activities in Aged Seeds of Pigeon Pea

Pigeon pea (Cajanus cajan (L.) Mills.) is one of the major grain legume crops grown in the tropics and sub-tropics and accounts for about 5% of world legume production. It is the fifth prominent pulse crop in the world and second most important pulse crop after chickpea in India. India is ranking first having about 90% of the world area and 85% of production. Organic farming in recent years gaining impetus due to realization of inherent advantages it confers in sustaining crop production under aberrant rain fed farming situations and also maintaining dynamic soil nutrient status and safe environment. In organic farming it is essential to use organically treated seeds as a source material for ensuring quality of organic product from unit area of land. Organic seed treatment is an effective method of seed enhancement technique using organically available resources. It speeds up seed germination, promotes faster growth and produces higher yield potential. Vigor tests have potential of assessing the seed physiological quality and among them; the accelerated ageing test has proved to be one of the most sensitive and efficient. It has been proven that the deteriorative effect of seed ageing is mainly due to production of free radicals (Bailly et al., 2008) and use of antioxidants can quench the free radicals and retain seed vigour during germination (Sattler et al., 2006). Recently, nano particles have been attempted to quench the reactive oxygen species and reduce the oxidative damage to improve the vigour and viability of seeds. Nano particles act as antioxidants through which they quench the superoxide anion radical (O2 -) and consequently generates O2 like catalase (Kajita et al., 2007). Nano particles are an effective scavenger of free radicals and suppress the propagation of lipid peroxidation (Watanabe et al., 2009). Among the several organics available, it has been proved that seaweeds possess natural antioxidant property, which can be attempted for seed treatments for vigour and viability maintenance either in commercial form or reducing the particles to near nano size. Seaweed extract is a new generation of natural organic fertilizers containing highly effective nutritious and promotes faster germination of seed and increase the yield and resistant ability of many crops. Seaweeds contain various trace elements, vitamins, amino acids and plant growth hormones which cause many beneficial effects on plant growth and development (Spinelli et al., 2010 and Abdel-Mawgoud et al., 2010). Application of seaweed extracts enhances seed germination, seedling vigour and yield (Economou et al., 2007; Dwivedi et al., 2014 and Lodhi et al., 2015). Therefore, the present experiment was to identify the effect of pre sowing, pre and mid storage treatment of seaweed nano powder in the fresh and aged seeds of pigeon pea.