Introduction

Okra is an important vegetable crop grown in India as well as in different tropical and sub-tropical part of the world. It is economically suitable for cultivation in Indian kitchen garden and also for large-scale commercial production.

Okra is a powerhouse of valuable nutrients, nearly half of which is soluble fiber in the form of gums and pectin. Soluble fiber helps to lower serum cholesterol, reducing the risk of heart disease. The other half is insoluble fiber which helps to keep the intestinal tract healthy, decreasing the risk of some forms of cancer, especially colorectal cancer. It’s high iodine contents control goiter. Okra provides an important source of vitamins, calcium, potassium and other mineral matters which are often lacking in the diet of developing countries (IBPGR, 1990). Being such an important crop there is the need of enhancement in okra production. Now a day’s researchers are using various growth regulators as well as bio-controlling agents for enhancing the crop productivity and also getting positive effect with that but these treatments were not easily available for the poor farmers and also to overcome from this problem vermiwash is a great alternative as it contain plant growth hormones like auxins and cytokinin apart from that also containing nitrogen, phosphorus, potash and other micronutrients. It contains nitrogen-fixing bacteria like Azotobacter sp., Arobactericum sp. and Rhizobium sp. and some phosphate solubilising bacteria. It acts as a plant tonic and helps to reduce many plant diseases. The present study was therefore carried out to evaluate the effect of vermiwash overgrowth regulators and bio-controlling agents through the method of priming.

Materials and Methods

Seeds of two Okra varieties viz: MIS077(V₁) and BHINDI No-10(V₂) were surface sterilized with 0.1% of Ca(OCl)₂ for five minutes which will be treated through the method of priming with vermiwash @ 20%(T₁) and 50%(T₂), growth regulators i.e. Indole-3-acetic acid @ 50ppm(T₃) and 100ppm(T₄), Gibberellic acid @ 50ppm(T₅)and 100ppm(T₆), Kinetin @ 50ppm(T₇) and 100ppm(T₈) and bio-controlling agents i.e.Trichoderma viride(T₉) and Trichoderma harzianum(T₁₀) v/w for 8 h. Seeds were taken out from the solution and allowed for shade drying. One set of unprimed control (T₀) was also maintained simultaneously. After shade drying primed and unprimed seeds of each variety were tested by using between the paper methods with three replications according to ISTA rules (Anon., 1999). Germination and root/shoot length were recorded after 7th days and at the same time; the fresh seedlings (root+shoot) were kept for drying in the oven at 80^oC. Dried samples were weighed with an electronic balance and vigour index I & II was calculated by following the method of Abdul-baki and Anderson (1973) as germination percent x seedling length and germination percent x seedling dry weight respectively. Data obtained were analyzed following the statistical procedure as described Panse and Sukhatame (1973).

Results and Discussion

Effect of priming treatment on growth parameters:-

A study was undertaken for improving the germination, stand establishment and growth of okra crop through employing the seed priming techniques. One open pollinated (OP) okra variety (MIS 077) and one hybrid okra variety (Bhindi No. 10) were primed  with vermiwash @ 20% and 50%, growth regulators IAA, GA₃, Kinetin @ 50 ppm and 100 ppm, and bio-controlling agents Trichoderma viride and Trichoderma harzianum. According to the obtained results primed okra seeds significantly enhanced the germination %, seedling length (cm.), dry weight (g.) and vigour in both the OP and hybrid variety of okra over unprimed control.

Among the treatments vermiwash 50% enhanced the maximum germination (96.5%) followed by 100ppm doses of Kinetin (92.83%), GA₃ (89.5%) and IAA (85.16%)(Table 1). Percent improvement in germination was observed 27.81%, 22.95%, 18.54%, 12.8% (Fig. 1) respectively in these mentioned treatments compared to control (75.5%). Variety V₂ showed enhancive value than V₁ as it is a hybrid variety but if we consider the enhancement of V₁ which is an Open pollinated(OP) variety, its germination improvement with vermiwash 50 % treatment(T₂) (95.6%) is maximum than the control of Hybrid variety (V₂)( 80.6%) (Table 1). Conclusively OP variety treated with vermiwash 50 % can be easily used by farmer instead of hybrid variety that is a cost effective method and promote the organic farming by protecting the environment from the threat of the use of chemicals in agriculture.

Seedling length is the sum of shoot and root length and it was very much enhanced through seed priming and the maximum enhancement was observed with vermiwash 50% (31.4 cm) (Table 1). This obtained value is 34.47% (Fig 1) enhanced compare to control (23.35cm).

Seedling dry weight which is a biomass of dried seedlings(root+soot) which is evaluated by calculating the reinvigoration of plant in terms of identifying the plant health and its real accumulated physiological content was also found maximum in vermiwash @ 50%(2.43g.) (Table 1) which is 72.12 % (Fig 1) more compared to the value of control (1.42 g.)

Vigour index I is the multiple product of germination X seedling length were also recorded maximum in vermiwash 50 % (3030.18) (Table 2) which is 27.81% (Fig 2) more than that of control (1765.763) (Table 2) and vigour index II is a multiple products of germination X seedling dry weight was also recorded maximum in vermiwash 50 % (234.56) (Table 2) which is 92.51 % (Fig 2) more than that of control(107.47) (Table 2). These results are also in harmony to some extent with the studies of Iqbal & Ashraf, 2007, Harris et al. 2004 in maize, rice, and chickpea, Rashid et al. 2004 in mungbean, Suresh et al. 2005 in chickpea and Rashid et al. 2006 in barley, nath et. al. 2009, Rai and bansiwal 2008.

Table 1: Showing the response of priming on germination percentage, Seedling length, and Dry weight in Okra.

Figure 1: Influence of treatments on Growth parameters over unprimed control in Abelmoschus esculentus L.   Click here to View figure

Table 2: Showing the response of priming on Vigour Index in Okra.

Figure 2: Influence of treatments on invigouration over unprimed control in Abelmoschus esculentus L.   Click here to View figure

References

1. Abdul-Baki, A.A. & Anderson, J.D. (1973). Vigour determination in soybean by multiple criteria. Crop Science, 13: 630-633
   CrossRef
2. Anonymous (1999).  International rules for seed testing. Seed Sci and Technol. 27: 27-32.
3. Harris D, Joshi A, Khan P.A., Gothkar P, Sodhi P.S., (2004). On-farm seed priming in semi-arid agriculture: development and evaluation in maize, rice and chickpea in India using participatory methods. Exp. Agric. 35: 15-29.
   CrossRef
4. International Board for Plant Genetic Resources IBPGR. (1990). Report on International Workshop on Okra Genetic resources held at the National bureau for Plant Genetic Resources, New Delhi, India.
5. Iqbal, M. and M. Ashraf. (2007). Seed treatment with auxins modulates growth and ion partitioning in salt-stressed wheat plants. J. Int.Plant. Biol., 49: 1003-1015.
   CrossRef
6. Nath,G., Singh, K. and Singh,D.K. (2009). Chemical Analysis of Vermicomposts / Vermiwash of Different Combinations of Animal, Agro and Kitchen Wastes.Australian Journal of Basic and Applied Sciences, 3(4): 3671-3676.
7. Panse.V.G. and Sukhatme. P.V. (1985). Statistical Methods for Agricultural Workers. ICAR. New Delhi. pp. 327 – 340.
8. Rai, N. and Bansiwal, K. (2008). Vermiwash: an excellent source of nutrition for plant growth. Electronic Journal of Environmental Sciences. 1: 19-21.
9. Rashid A., D. Harris, P.A. Hollington and M. Raffiq. (2004).  Improving the yield of mungbean (Vigna radiata) in the North West frontier province of Pakistan using on-farm seed priming. J. Expt. Agric., 40: 233-244.
   CrossRef
10. Rashid A., P.A. Hollington, D. Harris and P. Khan.(2006).On-farm seed priming for barley on normal, saline and saline-sodic soils in North West frontier province of Pakistan using on-farm seed priming. Europ. J. Agron., 24: 276-281.
    CrossRef
11. Suresh Babu S.Dr. B. S. Janagoudar Majo Advisor. (2005). Effects of seed priming with plant growth regulators and micronutrients on growth and yield of cotton (Gossypium herbaceum L.), under salinity stress. Journal of Applied Microbiology. (105):170–1177.