584

Ramesh Babu, B. and Patil, R.V.

Panse, V.G. and Sukhatme, P.V. (1967). Statistical methods for agricultural workers. Indian Council of Agricultural Research, New Delhi, p.145.

Singh, P.K., and Gopalakrishnan, T.R., (1999). Variability and heritability estimates in brinjal (Solarium melongena L.) South Indian Horticulture, 47: 174-178.

Robinson, H.F., Comstock, R.E., and Harvey, P.H., (1949). Estimates of heritability and degree of dominance in corn. Agronomy Journal, 41:353-359.

Sivasubramanian, S. and Menon, M., (1973). Heterosis and inbreeding depression in rice. Madras Agriculture Journal, 60 : 1139.

Sanwal, S.K., Baswana, K.S., Dhingra, H.R., Dhahiya, H.S., and Rana, M.K., (1998). Genetic variability and heritability studies in summer season brinjal (Solarium melongena L.). Haryana Journal of Horticulture Science, 27: 190-194. Sharma, T,V.R.S. and Kishan, (2000). Genetic variability and character association in brinjal (Solarium melongena L.) Indian Journal of Horticulture, 57 : 59-65.

UAS (Dharwad), (1991). Cultivation practices of Horticulture crops: Transitional regionregion IV (Zone 7 and 8). University of Agricultural Sciences, Dharwad, pp. 142146. Yadav, D.S., Prasad, A. and Singh, N.D., (1997). Character association in brinjal (Solarium melongena L.). Indian Journal of Horticulture, 54: 171-175. (Received : November 2004 Revised : July 2005)

______________ Madras Agric. J. 92 (7-9) : 584-588 July-September 2005

Research Notes

Seed size on crop growth and pod yield in groundnut J. RAMADEVI AND G. RAMA RAO Department of Plant Physiology, S.V. Agricultural College, Tirupati, A.P - 517 502

It is an established fact that the quality seed always pays dividend to the grower. For the last four to five decades the concept of seed size was studied on physiological parameters and yield for several crops including groundnut and results are controversial in most of the characters studied. Plants raised from smallest seed size were shorter compared to the taller plants obtained from the largest seed in groundnut (Ponnuswamy, 1985). On the other hand, seed size had been negatively correlated with plant height in sorghum (Govil, 1979). Contrary to the above results, grading did

not show any significant effect on plant height in groundnut (Sahoo et al., 1988). Hence, the present investigation was undertaken to study the effect of seed size on growth and pod yield of two prominent groundnut cultivars. A field experiment was conducted during Rabi 2002 on sandy clay loams with two cultivars (JL 24 and TPT 4) and five seed sizes (Bold, medium, small, shrivelled and ungraded seed). The experiment was laid out following randomized black design with three replications. The Kharif crop seed material was obtained from R.A.R.S Tirupathi. The

Seed size on crop growth and pod yield in groundnut

585

Table 1. Effect of seed size on field emergence and total dry matter in Groundnut cultivars Treatments

Field emergence (%)

Total dry matter (g/plant)

JL 24

TPT 4

Mean

JL 24

TPT 4

Mean

Bold Medium Small Shrivelled Ungraded

73.50 72.70 69.30 56.70 70.00

73.17 75.30 68.33 53.50 73.90

73.33 74.00 68.82 55.10 71.95

29.42 26.15 21.00 10.40 24.28

28.04 25.60 20.50 10.01 21.5

28.73 25.88 20.75 10.21 22.90

Mean

68.44

68.84

22.25

21.13

SEm ± CD at 5%

V 0.29 NS

S 0.464 1.378

V 0.036 0.108

S 0.057 0.171

bulk seeds of the two cultivars were graded into five different sizes by manually and by its test weight. The test weight of bold seed was 54.8 g in JL 24 and 46.5 g in TPT 4, medium seed (41.6 g in JL 24 and 38.03 g in TPT 4), small seed (29.5 g in JL 24 and 28.7 g in TPT 4), shrivelled seed (22.05 g in JL 24 and 21.25 g in TPT 4) and ungraded seed (34.2 g in JL 24 and 33.15 g in TPT 4). The crop was sown in an individual plot size of 5.0 x 2.1 m with a spacing of 30 x 10 cm. Recommended doses of fertilizer were applied. Prophylactic measures were taken up to protect the crop from all insect pests and diseases throughout the crop growth period. The data on field emergence was recorded at seven days after sowing. Five plants in each replication were tagged and the data on morphological observations were recorded. Five plants from each replication were dug out with pods at 10 days interval and dried in a hot air even at 80°C for 48 hours until they attained constant weight. Pods obtained from a square meter of each treatment were threshed individually and data on number of pods per plant, seed index and pod yield were recorded. Significant differences were observed in field emergence among seed sizes and interaction

VxS 0.656 1.948

VxS 0.085 0.242

between seed size and cultivar was significant (Table 1). The field emergence decreased as the seed size decreased. The field emergence was higher in bold and medium sized seed than ungraded seed in both genotypes. The high percent of field emergence recorded by bold seed compared to small and medium sized seed could be ascribed partly to large reserves present in seed and partly attributed to the role of small embryonic activation and enhanced growth rate (Khare et al., 1996). The field emergence of the ungraded seed could have been adversely affected more by the presence of shrivelled seed and immature seeds. Seeds of lower sizes exhibited lower field emergence than ungraded seed. This is an agreement with the findings of Dharmalingam and Basu (1989) in groundnut. There was an increase in plant height, number of primary branches, secondary branches and leaf area with increase in seed size from shrivelled to bold seed in both the cultivars viz., JL 24 and TPT 4 (Table 2). Plants raised from larger seeds had more plant height, more number of primary, secondary branches and leaf area while it was lower in shrivelled seed. The effects of early seed vigor might have been prolonged and certainly extended for beyond the period of dependency of seedlings

586

for endosperm food factor. The influence of seed vigor continued even up to harvest and the plants developed from bold seed consistently recorded higher values of growth parameters in groundnut (Ponnuswamy, 1985). The differences in number of primary and secondary ranches in groundnut var JL 24 was higher than that of TPT 4 at maturity and this might be due to genetic factor. The number of primary branches due to seed size was highly significant in the early stages as well as during the final phase of the crop growth (Ponnuswamy, 1985). The plants from bold seed produced higher leaf area in both the cultivars. It is partly due to vigorous growth of seedling from the emergence due to availability of more reserve food in the seed and partly due to more number of branches and in turn more number of leaves. The plants from bold seed recorded significantly higher total dry matter followed by medium seed while shirivelled seed recorded lower values (Table l). With regard to cultivars, JL 24 recorded higher values of total dry matter as compared to TPT 4. The plants from bold seed might have produced more dry matter due to large “initial capital” followed by “compound interest low” and also, plants from bold seed exhibited more leaf area, primary branches that in turn increased the dry matter. Similar observation was also reported by Dharmalingam and Ramakrishnan (1981) in groundnut. There was significant differences observed in number of pods per plant between cultivars and among seed sizes (Table3). The number of pods per plant was significantly higher in plants from bold seed with 15.10 followed by medium sized seed with 12.90. The lowest number of pods per plant was recorded in plants from shrivelled seed with 6.9 followed by small sized seed with 9.3. This might be due to the fact that plants from smaller seed were not able to supply the required metabolites

J. Ramadevi and G. Rama Rao

for better pod development. The early vigor, higher LAI, and dry matter production in plants from bold seed might have increased the number of filled pods and decreased the unfilled pods. The higher photosynthetic efficiency coupled with higher translocation efficiency might have resulted in proper filling of pods in plants from bold seed. Similar result was reported by Trinadhamurthy (1974) in groundnut. Among the cultivars, JL 24 recorded higher pods per plant (11.3) followed by TPT 4 (10.5). Seed index increased with increase in seed size (Table 3). The seed index of plants from bold seed was highest with 52.51 g followed by medium sized seed with 39.84 g. The plants from shrivelled seed recorded lower seed index with 21.65 g followed by small sized seed with 29.12 g. Increase in seed index might be due to better pod filling capacity when large seeds were used for sowing. The plants from large seeds were more vigorous from early stages itself, as evident from increased plant height and leaf area that might have helped for better pod filling. Similar result was reported by Trinadhamurthy (1974) in groundnut. The seed index also differed significantly between cultivars and cultivar JL 24 (34.26 g) recorded significantly higher seed index compared to TDT 4 (31.2 g). The pod yield was more in the plants from bold seed followed by medium sized seed while plants from shrivelled seed recorded less pod yield (Table3). Among the cultivars, JL 24 recorded higher pod yield (1671 kg/ha) compared to TPT 4 (1383 kg/ha). This might be due to higher number of pods per plant and seed index. Dharamalingam and Ramakrishnan (1981) observed increased pod yield in plants from bold seed because of persistency of seedling vigor during the entire crop growth, high vegetative growth and high peg to pod ratio in peanut.

No. of primary branches/plant

Plant height (cm)

Treatments

No. of secondary branches/plant

JL 24

TPT 4

Mean

JL 24

TPT 4

Mean

JL 24

Bold

22.30

20.10

21.20

5.60

5.60

5.60

6.00

6.00

Medium

22.20

18.80

20.50

5.40

4.60

5.00

6.00

Small

22.00

17.07

19.53

4.70

4.00

4.35

Shrivelled

18.90

16.30

17.60

4.20

3.40

Ungraded

19.90

18.90

19.40

5.50

Mean

21.06 V 0.079 0.236

18.23 S 0.125 0.374

VxS 0.178 0.529

5.08 V 0.069 0.205

SEm ± CD at 5%

TPT 4 Mean

Leaf area (Cm2 Plant-1) JL 24

TPT 4

Mean

6.00

812

726

769

5.50

5.75

734

687

711

3.00

3.30

3.15

531

495

513

3.80

3.00

2.30

2.65

275

224

250

4.70

5.10

5.50

5.50

5.50

715

669

692

4.46 S 0.109 0.324

VxS 0.154 NS

4.70 V 0.081 0.241

4.52 S 0.129 0.383

VxS 0.183 0.544

614 V 1.45 4.42

560 S 2.35 6.99

VxS 3.33 9.88

Seed size on crop growth and pod yield in groundnut

Table 2. Effect of seed size on crop growth in groundnut cultivars

Table 3. Effect of seed size on yield and yield components in groundnut cultivars Treatments

Seed index (g) JL 24 TPT 4 Mean

Pod yield (kg/ha) JL 24 TPT 4 Mean

Harvest Index (%) JL 24 TPT 4 Mean

Bold

15.50

14.70

15.10

40.20

38.90

39.55

2425

58.20

60.80

59.30

Medium

13.30

12.50

12.90

36.80

34.50

35.65

2001

1563

1782

59.27

58.90

59.10

Small

9.70

8.90

9.30

32.40

27.70

30.05

1527

1155

1341

51.40

51.70

51.60

Shrivelled

7.30

6.50

6.90

28.40

25.80

27.10

903

895

899

40.40

39.90

40.20

Ungraded

10.50

10.00

10.25

35.10

28.90

27.10

1501

1349

1425

52.30

55.80

54.40

Mean

11.26

10.52

-

34.58

31.16

-

1671

1383

-

54.10

54.60

SEm ± CD at 5%

V 0.065 0.193

S 0.102 0.305

VxS 0.145 NS

V 0.288 0.856

S 0.456 1.353

VxS 0.644 1.913

V 76 226 1

S 120 357

VxS 169 NS

V 0.377 NS

S 0.597 1.772

1953

2189

VxS 0.844 NS

587

No. of pods/plant JL 24 TPT 4 Mean

588

J. Ramadevi and G. Rama Rao

Harvest index increased with increase in seed size (Table 3). Higher harvest index in plants from bold seed might be due to more partitioning of dry matter towards pods. Similar result was reported by Chitti Babu (1992) in groundnut. The present study clearly indicated that plants raised from bold seed produced higher field emergence, total dry matter production, leaf area, harvest index and pod yield in groundnut.

References Chitti Babu, G. (1992). Performance of groundnut under different levels of pod grading, plant population and seed invigorations M.Sc. (Ag:) Thesis submitted to ANGRAU, Hyderabad. Dharmalingam, C. and Ramakrishnan, V. (1981). Studies on the relative performance of sized seed in peanut Cv. Pol. 2. Seed Res. 9: 5766. Dharmalingam, C. and Basu, R.N. (1989). Invigoration treatment for increased production in carried over seeds of mungbean. Seed and Farms. 15: 3436.

Govil, J.N. (1979). Genetic and phenotypic correlations between seeds and some biochemical and agronomic characters in sorghum. Seed Res. 7: 98-112. Khare, D., Rout, N.D. Rao, S. and Lakshmi, J.P. (1996). Effect of seed size on growth and field emergence in soybean. Seed Res. 23: 75-79. Ponnuswamy, A.S. (1985). Seed size in relation to leaf area, crop growth in groundnut. Madras Agril. J. 72: 352-354. Sahoo, A.K. Kulkarni and Vyakaranahal B S. (1988). Effect of seed size on yield and quality in bunch groundnut. Seed Res. 16: 136-142. Trinadhamurthy, B. (1974). Effect of seed size on plant stand, growth and yield of groundnut. M.Sc (Ag.) Thesis submitted to ANGRAU, Hyderabad. (Received : October 2003 Revised : December 2004)

______________ Madras Agric. J. 92 (7-9) : 588-592 July-September 2005

Research Notes

Screening of sugarcane varieties (Saccharum spp. hybrids) for salinity tolerance R. GOMATHI AND V. THANDAPANI Department of Plant Physiology, Sugarcane Breeding Institute, Coimbatore - 7.

Sett germination in sugarcane is an important physiological process, which is normally influenced by the age of the seed cane, variety, soil, quality of irrigation water and environmental factors. Among the factors causing sett germination, salinity is one of the most limiting factors, which causes 16.00 to 85.10% reduction in sett germination at varied salt

levels (Bajwa and Dev, 1970). At sugarcane Breeding Institute Coimbatore, elite clones were screened for salt tolerance through microplot condition at a constant salinity level of 8 dsm-1 and the rating for salt tolerance was based on performance of the genotype with respect to sett germination, yield and sucrose (%) juice (Annon,