Lec # Application of plant tissue culture & Biofertilisers Dr. Shah Rukh Abbas

Applications: Why do we Plant Tissue Culture? A single explant can be multiplied into several thousand plants in less than a year - this allows fast commercial propagation of new cultivars Taking an explant does not usually destroy the mother plant, so rare and endangered plants can be cloned safely Once established, a plant tissue culture line can give a continuous supply of young plants throughout the year In plants prone to virus diseases, virus free explants (new meristem tissue is usually virus free) can be cultivated to provide virus free plants

Plant ‘tissue banks’ can be frozen, then regenerated through tissue culture Plant cultures in approved media are easier to export than are soil-grown plants, as they are pathogen free and take up little space (most current plant export is now done in this manner) Tissue culture allows fast selection for crop improvement - explants are chosen from superior plants, then cloned Tissue culture clones are ‘true to type’ as compared with seedlings, which show greater variability Applications: Why do we Plant Tissue Culture?

Types of In Vitro Culture Culture of intact plants (seed and seedling culture) Embryo culture (immature embryo culture) Organ culture 1. shoot tip culture 2. root culture 3. leaf culture 4. anther culture Callus culture Cell suspension culture Protoplast culture

Tissue Culture Applications Micropropagation dihaploid production Protoplast fusion Genetic engineering

Biofertiliser –It involves inoculation of beneficial microorganisms that help nutrient acquisition by plants through fixation of nitrogen, solubilization and mobilization of other nutrients. –Biofertilizer concept goes back as early as 300 BC when our ancestors realized the importance of legume crops bearing nodules. –The perspective of biofertilizer came into existence through discovery of many organisms capable of nitrogen fixation, P-solubilization, P. mobilization, potash solubilization and micronutrient transformation in the soil. –The role of biofertilizers assumes special significance due to increased cost of chemical fertilizers and their ill effects on soil health Rhizobium bacteria inside nodule Legume root nodules

The term biofertilizer refers to preparation containing live microbes which helps in enhancing the soil fertility either by fixing atmospheric nitrogen, solubilization of phosphorus or decomposing organic wastes or by augmenting plant growth by producing growth hormones with their biological activities. Biofertiliser Bacteria in root surface Legume inoculationRhizobium Bacteria

Host plant Soil fertility Cropping practices Biological & environmental factors Factors affecting Performance (survival and efficacy) of biofertilisers:

1. Rhizobacterium Rhizobium bacteria in roots of legume plants fix atmospheric N 2 in nodules formed on the roots of plants. A pure and efficient strain of Rhizobium multiplied in the lab on a suitable medium by using shake flask technology or fermentation technology and inoculated into seed or root Rhizobium Innoculants: Use of Rhizobium culture in legumes is most promising. On average, its use can supply kg N/ha to legumes: increase yield up to 20 percent.

2. Azotobacter (Non-legume innoculants ) Is a free living microorganism that grow in the rhizosphere and fix atmospheric nitrogen non- symbiotically Makes it available to particularly cereals. Promotes seed germination, initial vigor of plants- by producing growth producing substances Isolation is carried out from soil near rhizosphere area. A highly efficient strain _Azotobacter chrooccocum is grown in the lab either as shake culture or using fermenter.

3. Azospirillum Azospirillum, [ Azospirillum lipoferum, biological nitrogen fixing grasses; enhance biomass-root system] Associative endo-symbiont on roots of grasses and similar types of plants. Also fixes atmospheric nitrogen and benefits host plants by supplying growth hormones and vitamins. Commonly used for preparation of commercial inoculants on a large scale, for cereals and grasses as it produces growth promoters in addition to fixing N2. Has good adaptability to temp, soil pH and wide host range.

Advantages of biofertilisers Renewable source of nutrients Sustain soil health Supplement chemical fertilizers. Replace 25-30% chemical fertilizers Increase the grain yields by 10-40%. Decompose plant residues, and stabilize C:N ratio of soil Improve texture, structure and water holding capacity of soil No adverse effect on plant growth and soil fertility. Stimulates plant growth by secreting growth hormones. Secrete fungistatic and antibiotic like substances Solubilize and mobilize nutrients Eco-friendly, non-pollutants and cost effective method.

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