PhD

Tuberose is one of the most important bulbous plants, much adored for its colour, elegance and fragrance. Among the commercially cultivated flowers in India tuberose occupies a prime position due to its popularity as cut flower as well as loose flower. It has got great potential in perfume industry also owing to the presence of much valued essential oil. The flower spikes are largely used for vase decoration and bouquet preparation and loose flowers for making garlands and in floral ornaments.

The mineral nutrition status can affect the yield and quality of any crop. Tuberose being rich in nutritional status, extracts high amount of nutrients from the soil. Application of huge quantities of fertilizers in the same field becomes essential for taking the ratoon crops and this may lead to destruction of soil properties in addition to increased cost of production.

It is now imperative to find an integrated nutrient management schedule for tuberose for an optimum and economic use of plant nutrients to reduce the cost of production and to improve the yield and quality of the flowers.

The study consisted of three experiments. Experiment 1 included sixteen different treatments which were the combinations of organic manures and growth promoting microorganisms along with inorganic fertilizers. In Experiment 2, effect of different organic manures alone on growth and yield of tuberose was studied. Single variety Prajwal was used for both the trials. Three superior treatments from Experiment 1 and two from Experiment 2 were selected for conducting the third experiment using single variety Prajwal and double variety Vaibhav.

In Experiment 1, the treatments 100:50:50 kg ha–1 NPK + poultry manure 22.2 t ha-1 (T3), 50:50:50 kg ha–1 NPK + poultry manure 22.2 t ha-1 (T14) and 50:50:50 kg ha1 NPK+ coirpith compost 85.71 t ha-1 (T16) exhibited superiority in terms of vegetative and floral characters. In experiment with different organic manures (Experiment 2) treatment with poultry manure alone (T4) and biogas slurry alone had positive influence on both growth and yield attributes.

In third experiment it could be observed that all the vegetative parameters were significantly improved by the application of 100:50:50 kg ha-1 NPK + poultry manure 22.2 t ha-1 (T1) in Prajwal and 50:50:50 kg ha-1 NPK+ poultry manure 22.2 t ha-1 (T2) in Vaibhav. Yield attributes like days to first spike emergence, field life of the spike, number of spikes per hill and quality parameters like length and girth of the spike, length of rachis and number of flowers per hill were positively influenced by treatment with poultry manure alone (29.63 t ha-1) in Prajwal. In Vaibhav also treatment with poultry manure alone (29.63 t ha-1) produced highest number of spikes per hill, where as quality parameters of the spike were improved by the application of poultry manure along with inorganic fertilizers. (100:50:50 kg ha-1 NPK + poultry manure 22.2 t ha-1). Concrete content of flowers (which indicates the percentage of essential oil) improved in T5 (biogas slurry alone) in both the varieties. The superiority of the treatment with poultry manure was also reflected in post harvest studies. From plant nutrient analysis, it could be observed that poultry manure either alone (29.63 t ha-1) or in combination with chemical fertilizers (100:50:50 kg ha-1 NPK + poultry manure 22.2 t ha-1 and 50:50:50 kg ha-1 NPK + poultry manure 22.2 t ha-1) recorded highest N and P content of leaves and tubers in both the varieties, where as treatment of coir pith compost along with inorganic fertilizers exhibited maximum K content. Soil properties like pH, organic carbon, available N, P and K were found to be improved by the treatment consisting of poultry manure.

Regarding the economics of cultivation, treatment with poultry manure alone (29.63 t ha-1) recorded maximum net income and highest B/C ratio in both the varieties (3.2 in Prajwal and 2.5 in Vaibhav) followed by 100:50:50 kg ha–1 NPK + Poultry manure 22.2 t ha-1and 50:50:50 kg ha-1 NPK + poultry manure 22.2 t ha-1 .

Considering overall performance, application of poultry manure at the rate of 29.63 t ha-1 as basal dose was proved to be highly beneficial for growth and yield improvement in tuberose.