Madras Agric. J. 92 (10-12) : 722 - 724 October-December - 2005
722
RESEARCH NOTES
EFFECT OF SEEDNUT PRESERVATION METHOD ON GERMINATION PATTERN IN COCONUT R. MARIMUTHU Coconut Research Station, Veppankulam 614 906, Thanjavur District
The seednut (12 months old) after harvest are not immediately planted in the nursery but are generally stored in shade for about a month till the husk becomes dry. Shade curing facilitates speedy and maximum germination (Thamban, 1982). But if the storage period exceed six weeks, germination is delayed (Child, 1964). However, when the situations are not conducive for immediate sowing of seednuts, the seednuts have to be preserved for long time (3 to 6 months) till the favourable situation arises. John and Narayana (1942) suggested preservation of seednuts in fine dry sand and this storage had no bad effect on the viability of seednuts or the quality of seedlings. In some of the coconut nurseries it is usual practice to preserve the seednuts inside the sand for a long period with view of getting uniform and early germination. But it is not known how long the seednuts can be preserved under sand. Therefore the present study was undertaken with the objective of finding out optimum period of preservation in open and sand condition. The experiment was conducted at Coconut Research Station, Veppankulam for two years (1999 - 2000 and 2000 - 2001), in split plot design replicated thrice. The plot size was 100 nuts per treatment per replication. The treatments comprised of 4 varieties viz., two tall varieties (ECT and VPM 3), one hybrid (VHC 2) and one dwarf variety ( MYD) and it was allotted in the main plot. In sub plots, six curing methods viz., T1-air curing 1 month, T2- air curing 2 months, T 3. air curing 3 months, T4 - sand curing 1 month, T5 - sand curing 2 months and T6 - sand curing 3 months duration. Before sand curing all
the seednuts were air cured for one month. Seednuts of all the varieties were collected in different months at one month interval and cured either under open shade condition or inside the sand as per the treatments. In sand curing, the seednuts were placed on sand with the stalk - end up layer by layer. The sand beds were kept always moist by sprinkling water. The nut germination were recorded at 3rd month and continued upto sixth month at one month interval. The two years data on germination were pooled and statistical analysis was done. The germination pattern of coconut seednut is important parameter since it significantly attribute for outturn of quality seedlings. At third month after sowing 87.8%, 88.5%, 88.4% and 81.5% germination were recorded in ECT, VPM 3, VHC 2 and MYD respectively when the seednuts were sand cured for 3 months. For all four varieties, under sand curing method the increment in the germination beyond third month was very meager. Irrespective of varieties, the variations in the germination of nuts due to different period of sand curing either one or two or three month did not adversely affect the germination but favourably influence the early and uniform germination for all the four coconut varieties under present study. At third month, air cured seednuts (T1) registered 50.5%, 52.5%, 62.5% and 74.5% germination in ECT, VPM 3, VHC 2 and MYD respectively. And the germination was considerably continued till sixth month. The ununiformity of germination would cause for more variations in seedlings growth and it would result in poor outturn of quality seedlings.
EFFECT OF SEEDNUT PRESERVATION METHOD ON GERMINATION PATTERN IN COCONUT
Table 1. GERMINATION PATTERN (%) Varieties ECT
3rd month
Month of germination observation 4th month 5th month
T1
50.5
65.4
78.4
91.5
T2
40.2
60.5
75.4
70.4
T3
35.4
45.4
54.3
60.5
T4
85.5
87.2
88.1
90.5
T5
86.7
87.5
90.4
92.5
T6
87.8
90.5
91.7
92.6
VPM 3 T1
52.5
67.2
79.5
88.5
T2
44.3
63.4
76.4
72.4
T3
38.2
47.4
56.5
59.7
T4
86.4
89.1
89.2
89.5
T5
87.4
88.5
90.4
92.4
T6
88.5
90.8
91.5
93.4
T1
62.5
75.4
85.7
92.4
T2
52.5
59.6
67.4
73.1
T3
48.6
54.5
62.7
68.4
T4
85.4
87.4
90.5
94.4
T5
88.4
89.5
91.6
93.4
T6
88.1
90.5
92.4
94.2
T1
74.5
78.4
79.2
82.0
T2
45.5
48.4
49.5
50.4
T3
28.4
29.2
30.0
30.4
T4
75.5
78.4
78.8
80.2
T5
80.4
80.8
81.0
81.2
T6
81.5
81.8
82.0
82.8
6th month
VHC 2
MYD
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R. MARIMUTHU
724 The total nut germination was significantly influenced by the varieties and curing method while the interaction effect was non significant. The highest nut germination of 85.5% was registered with VHC 2 and it was on par with ECT and VPM 3 (Table 2). The lowest germination of 67.9% was
recorded with MYD. The reason for poor germination of MYD might be due to long period of air curing and the air curing period may be reduced less than one month. Further study in this line is required.
Table 2. GERMINATION (%) at 6 TH MONTH ECT
VPM3
VHC2
Dwarf
Mean
T1
91.5
88.5
92.4
82.0
88.6a
T2
70.4
72.4
73.1
50.4
66.6
T3
60.5
59.7
68.4
30.4
54.8
T4
90.5
89.5
94.4
80.2
88.7
T5
92.5
92.4
93.4
81.4
89.9
T6
92.6
93.4
94.2
82.8
90.8
Mean
83.0
82.7
85.5
67.9
CD (5%) Variety =5.2, Curing method =7.8, Variety X Curing method =NS Among the curing methods, sand curing for 3 months registered highest nut germination (90.8%) and it was on par with sand curing 1 month, sand curing 2 months and air curing for one month. Though the total nut germination in sand curing and air curing method was comparable, the earliness and uniformity of germination was more favourable in sand curing method. Preservation of seednuts beyond one month resulted in very poor germination (66.6% and 54.8%) for all four varieties.
MYD may be preserved for one month in open shade condition followed by sand curing for 2 or 3 months.
From the results of the field experiment it may be inferred that to get more germination at the earliest, the seednuts of ECT, VPM 3, VHC 2 and
Thampan, P.K. (1982). Hand book on Coconut Palm. Oxfor & IBH Publishing Co. ^-^ New Delhi. P. 71.
REFERENCE Child, R., (1964). Coconuts. 2na Edition. Tropical Agriculture Series. P: 100 John, CM. and Narayana, G.V., (1942). A simple method of preserving seed ' -/ coconuts. Madras agric. J., 30 : 148 - 149.
