NSave Nature to Survive

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1 ISSN: NSave Nature to Survive : Special issue, Vol. VI: : 2014 AN INTERNATIONAL QUARTERLY JOURNAL OF ENVIRONMENTAL SCIENCES CORRELATION OF DIFFERENT VIGOUR TESTS WITH FIELD EMERGENCE OF PADDY GENOTYPES S. N. Vasudevan et al., KEYWORDS Accelerated aging Paddy Vigour Proceedings of National Conference on Harmony with Nature in Context of Environmental Issues and Challenges of the 21 st Century (HORMONY ) November 28-30, 2014, Udaipur, organized by Department of Environmental Sciences, Faculty of Earth Sciences M. L. Shukhadia University, Udaipur (Rajasthan) in association with National Environmentalists Association, India 333

2 NSave Nature to Survive QUARTERLY S. N. VASUDEVAN, J. B. MARUTHI, S. R. DODDAGOUDAR, B. N. RAGHU* AND D. HANUMANTHAPPA Department of Seed Science and Technology,University of Agricultural sciences, Raichur , India raghubn123@gmail.com ABSTRACT An attempt was made to correlate twelve laboratory vigour tests with field emergence to standardize the vigour test in paddy for which three seed lots of each BPT-5204, IR- 64 and MTU-1010 were used. Germination test (0.927, and 0.886), speed of germination (0.998, and 0.982), seedling dry weight (0.997, and 0.786), vigour index (0.881, and 0.975), accelerated aging (1.00, and 0.993) and cold test (0.918, and 0.680) were positively correlated with the field emergence in genotypes BPT-5204, IR-64 and MTU-1010, respectively. Among all the vigour tests accelerated aging test had highest positive and significant correlation with field emergence (1.00, and BPT-5204, IR-64 and MTU-1010, respectively). Hence, this test was found to be good indicators of vigour in paddy. INTRODUCTION Rice (Oryza sativa L.) is the most important and extensively cultivated cereal crop stand next to wheat in the global food grain production and is the main source of livelihood for more than 150 million rural households (Bidhan Roy et al., 2013). India being the second largest producer of rice but still lacks behind due to the rising demand, saturation of cultivable land and availability of quality seeds for sowing (Rakesh Kumar et al., 2013). A good quality seeds are often free from diseases and posses high germinability and vigor. The benefits of various production inputs and improved farming technologies can be gained only when highly vigorous seeds are used for sowing. Seed quality is one of the major factors that determines the success or failure of a crop. Seed vigor is a key element of seed quality. Seeds selected based on high vigor will produce more uniform, vigorous stand of plants resulting ultimately higher yields per area. Seed vigor is an aspect of seed quality which control field stand establishment and vigor tests are required to obtain reliable assessments of field performance (Chhetri, 2009). Some of the scientists validated the vigour test for different crops viz., electrical conductivity of seed soak water for garden pea (Mathews and Powell, 2006), accelerated ageing for soybeans (Tekrony and Egli, 1997) and controlled deterioration for small seeded crops, has been shown to relate to emergence (Powell and Mathews, 2005). The present study was planned with hypothesis that germination test cannot adequately reflect the loss in performance potential that occur before germination capacity is lost. In adverse conditions, laboratory germination test results may not reflect on accurate assessment of field potentiality for cereals and therefore advocated to use of vigour test as a means of assessing the planting value of seed lots. In rice, seed vigour was reported to influence growth parameters and yield significantly. Hence, the present investigation has been contemplated to establish the relation between field emergence and certain vigour tests in paddy. The objective of this study therefore was to determine suitable vigour test to predict relative seedling emergence in paddy among different vigour tests. MATERIALS AND METHODS *Corresponding author The present investigation was carried out in the Department of Seed Science and Technology, University of Agricultural Sciences, Raichure during the year The seeds of paddy varieties viz., IR-64, BPT-5204 and MTU-1010 were obtained from Karnataka state seed corporation, Raichure. The three seeds lots of each cultivars were created by subjected to accelerated aging test for 0, 3 and 6 days. The seed samples of each lot were subjected to the following tests. Volume weight (g) Fifty gram of seeds were sampled from each seed lot and replication wise and 334

3 CORRELATION OF DIFFERENT VIGOUR TESTS Table 1: Statistical summary of various vigour test results Vigour test Genotypes BPT 5204 IR64 MTU1010 Volume weight (gm) Mean Range CD(p = 0.05) NS NS NS Test Weight(gm) Mean Range CD(p = 0.05) NS NS NS Germination (%) Mean Range CD(p = 0.05) Speed of germination Mean Range CD(p = 0.05) 0.63 NS 1.03 Seedling Length(cm) Mean Range CD(p = 0.05) NS NS NS Seedling Dry weight (mg) Mean Range CD(p = 0.05) 0.68 NS 0.73 Vigour index Mean Range CD(p = 0.05) Electrical conductivity (uscm -1 ) Mean Range CD(p = 0.05) TDH Mean Range CD(p = 0.05) Cold test (%) Mean Range CD(p = 0.05) Accelerated aging test Mean Range CD(p = 0.05) Field emergence (%) Mean Range CD(p = 0.05) NS-Non significant Table 2: Simple correlation coefficients between vigour tests and field emergence Vigour test Genotypes BPT IR-64 MTU-1010 Volume weight Test weight Germination Speed of germination 0.998* Seedling length Seedling dry weight Seedling vigour index Electrical conductivity TDH Cold test Accelerated ageing test 1.00* * Correlation is significant at the 0.05 level weighed. The average weight of the seed was recorded in grams as volume weight of seed. Seed Test weight (g) 6000 seeds in six replication each were counted separately and weighed. The mean was expressed in grams (ISTA, 2006). Germination test Germination per cent was determined as per ISTA rules for seed testing. The seeds were placed in rolled paper towels. Hundred seeds of four replications were tested at a constant temperature of 25 o C. The numbers of normal seedlings were evaluated on 14 th day and per cent germination was expressed on normal seedling basis (ISTA, 2006). Speed of germination Seed germination test was conducted as per the above procedure and daily germination counts were recorded with 3-5 mm radical was considered as germinated. The speed of germination was calculated by using formula suggested by Maguire (1962) Mean seedling length From the standard germination test, ten normal seedlings were selected at random in each replication on final count. The shoot length was measured from collar region to the point of attachment of cotyledons and root length from the collar region to the tip of the primary root, sum of shoot and root length 335

4 S. N. VASUDEVAN et al., constitute the seedling length and mean was calculated and expressed in centimeters (ISTA, 2006). Seedling dry weight Ten seedlings used for measuring the seedling length was kept in the hot air oven at 85±1 C for 24 hours. The dry weight (mg) was measured and expressed as mean dry weight (mg/seedling) (ISTA, 2006). Seedling vigour index It was computed by adopting the formula as suggested by Abdul-Baki and Anderson (1973) and expressed in whole number. Seedling vigour index = Germination (%) Mean seedling length (cm). Electrical conductivity of seed leachates To measure the electrical conductivity of the seed leachate four replicates of one hundred seeds were taken, washed with distilled water and soaked in 50 ml distilled water for 6 hours. The electrical conductivity of the seed leachate was measured in a digital conductivity meter (Type MCD-287) with a cell constant of the electrode being one. The electrical conductivity of seed leachate was expressed in usm -1 (ISTA, 2006). Total dehydrogenase activity Determined as per ISTA rules for seed testing (ISTA, 2006). Cold test Cold test described by Agrwal and Dadlani (1987) was adopted. Accelerated aging test The seed samples were kept in Accelerated aging chamber and exposed the seeds to 40±2 o C temperature and 100% relative humidity for 3 days, then seeds were dried under shade overnight and germination test was conducted (Delouche and Baskin, 1973). Field emergence test Field emergence was determined by sowing one hundred seeds from each treatment in four replications in the soil boxes. The emergence counts were made on 10 th day after sowing and expressed in per cent (ISTA, 2006). The data were subjected to analysis of variance and F test was carried out. The data obtained from various test were correlated with field emergence (Panse and Sukhatme, 1978). RESULTS All the paddy varieties tested had significantly differences between seed lots in vigour parameters except for volume weight, test weight and seedling length (Table 1). The difference was high between the seed lots when seeds were subjected to accelerated aging which ranged from % in BPT- 5204, % in IR-64 and % in MTU While marginal difference was recorded between seed lots in respect of volume weight which was ranged from gm in BPT-5204, gm in IR-64 and gm in MT Among the laboratory vigour tests accelerated aging test expressed positive and highly significant correlation with field emergence but the association was statistically significant for cv. BPT-5204 (1.00) and non significant for IR-64 (0.942) and MTU-1010 (0.993) (Table 2). Similarly Padma and Murulimohan Reddy (2002) reported variation among the varieties with respect to correlation association between field emergence and other vigour tests. In the present investigation volume weight was not correlated with field emergence in all the cultivars. The results of electrical conductivity in all three cultivars, test weight in MTU-1010 and seedling length in IR-64 and MTU-1010 was negatively correlated with field emergence. However the correlation was non significant. Germination test, speed of germination, seedling dry weight, vigour index and cold test was positively correlated with field emergence (Table 2). DISCUSSION The high correlation between accelerated aging with field emergence suggests that accelerated aging test can be used in testing the vigour instead of standard laboratory germination test. The two most important factors that influence the life span of seeds are relative humidity and temperature. The effect of relative humidity (and its subsequent effect on seed moisture) and temperature are highly interdependent. Most crop seeds lose their viability at relative humidity approaching 80% and temperatures of 25 to 30ºC (Copeland and McDonald, 1995). Accelerated aging is a physiological stress test that permits controlled deterioration of seeds due to expose to high temperature and high relative humidity (greater than 90%) (ISTA, 2006). Seed moisture content and high temperature influence seed metabolism. High relative humidity increases seed moisture, which results in biochemical events such as increase hydrolytic enzyme activity, free fatty acids where as high temperature serves to enhance the rate at which many enzymatic and metabolic reaction occurs and there by increases the metabolic activity of hydrolyzed substrates and enzymes causing more rapid rate of deterioration (Khan et al., 2010). The decreases in both root and shoot lengths and seed germination by accelerated aging may be a result of progressive loss of seed viability and can be used as an excellent method for determination of vigour (Mosavi et al., 2011). The accelerated aging test expressed positive and highly significant correlation with field emergence might be due to the test results establish the maximum plant producing potential of seed lots and correlate quite well with emergence under unfavorable field conditions (high temperature and high relative humidity) and seldom are these conditions encountered in the field (Suraj Chhetri, 2009). Data from previous research on small grain crop similarly indicated that, compared with standard germination, accelerated aging was more sensitive in ranking seed lot quality in paddy (Padma et al., 2002; Chea, 2006; Singkanipa, 2008 and Kapoor et al., 2011), watermelon (Mavi and Demir 2007) and wheat (Khan et al., 2010). Finally it can be concluded that the accelerated aging test is a good indicator of vigour in rice. However the difference was high between the seed lots. The difference between the seed 336

5 CORRELATION OF DIFFERENT VIGOUR TESTS lot was magnified by this test and also this test was positively correlated and significant association with field emergence. Hence, this test can be used as vigour test for rice. REFERENCES Abdul-Baki, A. A. and Anderson, J. D Vigour determination by multiple criteria. Crop Sci. 13: Agrwal, P. K. and Dadlani, M Techniques in Seed Science and Technology. South Asian Publishers, New Delhi. Chea, S Seed Vigour Tests and Their Use in Predicting Field Emergence of Rice. M.Sc. thesis, Khon Kaen University, Thailand. Copeland, L. O. and McDonald, M. B Principle of Seed Science and Technology. Chapman & Hall, New York. Delouche, J. C. and Baskin, C. C Accelerated aging techniques for predicting the relative storability of seed lots. Seed Sci. Technol. 1: Dhanwani, R. K., Sarawgi, A. K., Solanki, A. and Tiwari, J. K Genetic variability analysis for various yield attributing and quality traits in rice (Oryza sativa L.). The Bioscan. 8(4): I.S.T.A., International Rules for Seed Testing. Seed Sci. & Technol. 24(Suppl): Kapoor, N., Arya, A., Siddiqui, A. M., Kumar, H. and Amir, A Physiological and biochemical changes during seed deterioration in aged seeds of rice (Oryza sativa L.). Am. J. Plant Physiol. 6(1): Khan, A. Z. P., Shah, F., Khan, M. H., Amanullah, S., Perveen, S., Nigar, S. K. and Zubair, M Vigour tests used to rank seed lot quality and predict field emergence in wheat. Pak. J. Bot. 42(5): Maguire, J. D Speeds of germination-aid selection and evaluation for seedling emergence and vigor. Crop Science. 2: Matthews, S. and Powell, A. A Electrical conductivity vigour test: physiological basis and use. Seed Testing International. 131: Mavi, K. and Demir, I Controlled deterioration and accelerated ageing tests to predict seedling emergence of watermelon under stressful conditions and seed longevity. Seed Sci. and Technol. 35: Mosavi, N. S. M., Gholami, H., Kord, G. H., Sadeghi, M. and Sedighi, E Free fatty acid and electrical conductivity changes in cotton seed (Gossypium hirsutum). Int. J. Agric. Sci. 1(2): Padma, V. and Murali Mohan Reddy, B Standardization of laboratory vigour test for paddy. Seed Res. 30(1): Panse, V. G. and Sukhamate, P. V Statistical methods for agricultural workers, third revised edition, Indian Council of Agricultural Research, New Delhi. p Powell, A. A. and Matthews, S Towards the validation of the controlled deterioration vigour test for small seeded vegetables. Seed Testing International. 129: Roy, B., Surje, D. T. and Mahato, S Biodiversity of farmers varieties of rice (Oryza sativa L.) at repository of Uttar Banga Krishi Viswavidyalaya: a reservoir of important characters. The Ecoscan. 5: Singkanipa, V Personal communication. Head of seed quality control group, Nakhon Ratchasima Rice Seed Center, Nakhon Ratchasima, Thailand. Suraj Chhetri, Identification of accelerated aging conditions for seed vigor test in rice (Oryza sativa L.). M. Sc Thesis submitted to Suranaree University of Technology. Tekrony, D. M. and Egli, D. B Relationships between laboratory indices of soybean seed vigour and field emergence. Crop Science. 7:

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