Influence of Seed Priming with Chemicals, Micronutrients and Bio-Inoculants on Growth and Yield Attributes in Foxtail Millet (Setaria italica L.)

Foxtail millet is commonly known as Italian millet, German millet, Siberian millet, and foxtail bristle grass. Foxtail millet grows 2–5 feet tall and can be cultivated in drier and cooler regions when compared with other millets. It is currently grown in China, India, Europe, particularly in Portugal, Turkey, Hungary, France and Spain, in Asia, primarily in Korea, Pakistan, Myanmar, Bhutan, Nepal, and South Africa. It is used for feeding birds and as livestock feed in the developed countries and for food in some parts of Asia. It International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 8 Number 10 (2019) Journal homepage: http://www.ijcmas.com

is suitable for inclusion in multiple or intercropping systems because of its short duration nature.
Seed enhancement is a term used in industry and in scientific literature to describe beneficial techniques performed on seeds, after harvesting but prior to sowing for improving a crop's harvested yield and quantity. Rapid germination and emergence is an important determinant of successful plant establishment (Heydecker et al., 1975) and seed priming has presented promising results, for many crop seeds (Bradford, 1986).
Seed priming is a controlled hydration process that involves exposing seeds to low water potentials that restrict germination (radicle protrusion), but permits pre germinative physiological and biochemical changes to occur (Heydecker and Coolbear, 1977;Bradford, 1986;Khan, 1992). Upon rehydration, primed seeds may exhibit faster rate of germination, more uniform emergence, greater tolerance to environmental stresses, and reduced dormancy in many species (Khan, 1992). The present investigation was carried out to know the different seed priming effect on growth and grain yield of foxtail millet.

Results and Discussion
Foxtail millet seeds primed with T 12 (Seed priming with Azospirillum sp. @ 20% + Pseudomonas fluorescens @ 20% + Phosphobacter @ 20%+ ZnSO 4 0.1% + Boron 0.1%) recorded highest plant height (52.25cm, 133.70cm and 134.12cm), number of tillers (5.18, 5.37 and 5.37 respectively)at 30, 60 DAS and at harvest respectively. Days to 50% flowering and days to maturity recorded lower number of days (52 and 92 days respectively) in T 12 . While, control (T 1 ) recorded lowest plant height (35.70cm, 109.30cm and 116.80cm) and number of tillers (3.54, 3.85 and 3.8) at 30,60DAS and at harvest respectively. Days to 50% flowering and days to maturity recorded highest number of days (55 and 96 DAS respectively) in control (T 1 ) ( Table 1). Improvement in growth parameters might be due to combined effect of bio fertilizers and micronutrients. The enhanced plant height may also be due to the improved and faster plant emergence in bio-primed seeds which might have created nitrogen fixation by the plant, phosphorous solubilization and also cooperative competition among the plants for light and resulted in taller plants. In addition increased the nutrient availability, Azospirillum and PSB also effects the plant growth through production of growth harmone like IAA, GA 3 , Cytokinin (Sattar and Gaur, 1987).  Janardan Yadav et al., (2010) in chickpea concluded that the increase in plant height might be due to the early emergence of the bioprimed seeds which makes the plant to compete well with the weeds and higher rate of accumulation of dry matter due to atmospheric nitrogen fixation and phosphorous solubilization. Raj et al., (2004) and Abdullahi et al., (2014) reported significant difference for number of tillers per plant in pearl millet, Gangwar and Sinha (2014) in rice. Increased leaf production due to seed bio-priming might be due to Pseudomonas fluorescence which contains physiologically active substances viz., growth regulators and nutrients that promote profuse number of tillers per plant as noticed by Sharifi et al., (2011) in maize.
Significant difference is found for all the yield parameters due to seed priming treatment. The increase in the panicle length may be due to the synthesis of amino acid and chlorophyll and better carbohydrates transformation which resulted in better growth and length of panicle which ultimately produced more number of seed per panicle resulting in increasing panicle weight there by increasing the yield. Similar results were also reported by Niranjan raj et al., (2004) in finger millet and Prasad et al., (2009) in wheat. Increase in yield was also contributed by Zn which attributed to the enhanced synthesis of carbohydrates and their transport to the site of grain production crop (Pedda-Babu et al., 2007). Similar results were also reported by various researchers due to Zinc seed priming on seed yield of wheat (Nazir et al., 2000;Harris et al., 2005;Aboutalebian et al., 2012).
The influence of bio-inoculants on the grain yield might be through their effect on actively growing regions in such a way that they encourage nitrogen fixation, phosphorous solubilization and mobilize the nutrients absorbed elsewhere towards the shoot resulting in better vegetative growth and subsequently increased yield as noticed by Nezarat and Gholami (2009) in maize. Azospirillum sp. and phosphobacter have improved photosynthesis by increasing water and nutrients absorption leading to produce more assimilate and improves translocation of metabolites from sources to sink which in turn increased the test weight in seeds (Mirzaei et al., 2010).