Luffa Research Report
Seed Treatment Effects on Emergence of Luffa Sponge
Gourd
Todd C. Wehner and Tammy L. Ellington
Department of Horticultural Science, North Carolina
State University, Raleigh, NC 27695-7609
Cucurbit Genetics Cooperative Report 20: 63-64
Luffa (or loofah) sponge gourds (Luffa aegyptiaca
Mill) are increasing in popularity in North America. However,
additional research is needed to solve some of the production
problems for luffa, especially in the area of seed germination.
There is little published information in luffa on the effects
of seed treatment on germination, or of growth regulators on sex
expression. However, it would be useful to increase the germination
rate of luffa seeds, which is often below 75%. It would also be
useful to increase the percentage of pistillate flowers on the
luffa plants for easier hybridization. Luffa and cucumbers are
members of the Cucurbitaceae family. Cucumbers respond favorably
to growth regulators for increasing the percentage of pistillate
flowers (1, 2). The objective of this research was to determine
the effects of several pre-planting treatments on seed germination
and growth regulators on sex expression in luffa sponge gourds.
Six treatments were applied to 'Fletcher' luffa seeds
prior to planting. A total of 60 seeds were used per treatment
combination. The treatments included water, acetone, gibberellic
acid-3 (GA3), ethephon, scarification and a control. The control
consisted of untreated, dry seeds. In the water treatment, seeds
were soaked in distilled, aerated water for 87 hr at 25 C. In
the acetone treatment seeds were soaked for 16 hr at 25 C in acetone.
In the GA3 treatment, seeds were soaked for 16 hr at 25 C in a
solution of 0.1 mM GA3 plus 200 ml acetone. In the ethephon treatment
seeds were soaked in 3.5 mM ethephon mixed with 200 ml acetone
for 16 hr at 25 C. The scarification treatment involved shaking
the seeds for 2 minutes in a 762 mm diameter closed PVC tube lined
with sandpaper. After treatment application, the seeds were planted
in a peatlite mix in flats in the greenhouse. Emergence data were
taken two weeks after seeding.
After seedling emergence data were taken, the seedlings
were transplanted into the field. Ethephon was sprayed on seedlings
until runoff 0, 1, or 2 times using a rate of 100 mg/L (+4 drops
Tween-20). Seedlings received either one treatment of ethephon
at the first leaf stage, two treatments of ethephon at the first
and third leaf stages, or no treatment (the control). As the plants
were maturing, the number of pistillate nodes out of a total of
twenty nodes on five plants was recorded. The data collected were
analyzed using the GLM procedure of SAS.
There was a significant increase in the percentage
emergence when luffa seeds were soaked in water relative to the
acetone, ethephon, GA3, and scarification treatments (Table 1).
However, the water treatment was not significantly different from
the control. Therefore, none of the seed treatments improved the
rate of emergence of the luffa seedlings, and all but the water
soaking treatment made the percentage emergence worse.
Based on the tests conducted, spraying seedlings of
'Fletcher' luffa gourds with ethephon did not increase the percentage
of pistillate flowers when the seeds had been treated with acetone,
GA3, or scarification. Significant differences were found with
the ethephon and water seed treatments when ethephon was applied
at the first true leaf stage. The control seed treatment showed
a significant increase in percentage pistillate flowers when the
seedlings were not sprayed with ethephon (Table 2).
We hoped that luffa would respond to ethephon in the
same way that cucumbers do. However, our experiment indicated
that ethephon applied at the tested rates had no significant effect
on sex expression. Similarly, none of the treatments enhanced
seed emergence from the soil. Additional research is needed to
identify useful treatments for improvement of seed emergence and
pistillate flower production in luffa sponge gourd.
Literature Cited
1. McMurray, A.L. and C.H. Miller. 1968. Cucumber
sex expression modified by 2-chloroethanephosphonic acid. Science
162:1396-1397.
2. Pike, L.M. and C.E. Peterson. 1969. Gibberellin
A4/A7 for induction of staminate flowers on the gynoecious cucumber.
Euphytica 18:106-109.
Table 1. Effect of seed treatments on seedling emergence
in uffa sponge gourd.z
|
Seed treatment
|
Percentage emergence
|
|
Acetone
|
47
|
|
GA3
|
56
|
|
Ethephon
|
57
|
|
Scarification
|
63
|
|
Water
|
80
|
|
Control
|
72
|
|
LSD (5%)
|
11
|
|
CV (%)
|
22
|
z Data are means of two replications of 60 seeds each.
Table 2. Effect of seed treatments on seedling emergence
in uffa sponge gourd.
|
Seed
|
Number of
|
Percentage
|
|
treatment
|
ethephon appllicationsz
|
pistillate nodesy
|
|
Acetone
|
0
|
17
|
|
|
1
|
16
|
|
|
2
|
15
|
|
GA3
|
0
|
17
|
|
|
1
|
18
|
|
|
2
|
20
|
|
Ethephon
|
0
|
11
|
|
|
1
|
35
|
|
|
2
|
14
|
|
Scarification
|
0
|
19
|
|
|
1
|
21
|
|
|
2
|
19
|
|
Water
|
0
|
33
|
|
|
1
|
9
|
|
|
2
|
20
|
|
Control
|
0
|
28
|
|
|
1
|
23
|
|
|
2
|
18
|
|
LSD (5%)
|
|
6
|
|
CV (%)
|
|
39
|
z Ethephon was applied in one of three treatments: 0=none,
1=once and 2=twice.
y Data are means of two replications of five plants,
counting 20 nodes per treatment.
|
