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Singh, B.P. and W.F. Whitehead. 1996. Management
methods for producing vegetable amaranth. p. 511-515. In: J. Janick (ed.),
Progress in new crops. ASHS Press, Arlington, VA.
Management Methods for Producing Vegetable Amaranth
Bharat P. Singh and Wayne F. Whitehead
- METHODOLOGY
- Planting Date Study
- Cultivar Selection Study
- Nitrogen Fertilization Study
- RESULTS
- Planting Date
- Cultivar Selection
- Nitrogen Fertilization
- SUMMARY
- REFERENCES
- Table 1
- Table 2
- Table 3
Amaranth (Amaranthus spp.) is a new crop with ancient history. Members
of Amaranthus spp. have been grown for centuries for vegetable and grain
in different parts of the world (NRC 1984). Amaranth is consumed as vegetable
in Africa, Caribbean, China, Greece, India, Italy, Nepal, and South Pacific
Islands (Stallknecht and Schulz-Schaeffer 1993). Amaranthus species
most commonly utilized as vegetable have short plants with wide leaves and
small inflorescence (Huang 1980). However, it is common to find same plant
type used both for leaf and grain (Saunders and Becker 1984; Tucker 1986).
The awareness in the United States of the potentiality of amaranth, mainly as a
grain and to a lesser extent as a vegetable crop, was generated by the Rodale
Research Center, Kutztown, Pennsylvania in the mid-1970s. Immigrants from the
countries where vegetable amaranth is consumed widely, however, were the real
impetus behind creating a demand for this vegetable in the United States.
Since then, it has been realized that amaranth can also fill a void for fresh
leafy vegetables during the summer months (Makus and Davis 1984; Singh and
Whitehead 1993). Amaranth leaves are comparable to spinach (Spinacia
oleracea L.) in taste (Abbott and Campbell 1982). They are also a good
source of dietary fiber and contain high amounts of protein, vitamins, and
minerals (Makus and Davis 1984; Teutonico and Knorr 1985; Willis et al. 1984).
However, unlike spinach, an ideal season for producing amaranth in the
temperate climate is during the hot months of the summer season. In addition,
research has shown that green yields from amaranth produced at different
locations in the United States are high enough to make commercial exploitation
feasible (Berberich 1980; Campbell and Abbott 1982; Makus 1984; Sealy et al.
1990; Singh and Whitehead 1991). In this paper, we present results of cultural
studies (planting date, cultivar selection, and N-fertilization) of vegetable
amaranth.
Field experiments to determine the suitable time period for planting amaranth
were carried out during 1992 and 1993. The experiments were conducted on a
Dothan sandy loam soil (fine loamy, siliceous, thermic, Plinthic Paleuult).
Amaranthus tricolor genotype RRC 241 was used for planting. Different
planting dates comprised the treatments, which were arranged in a randomized
complete block design with four replications. Each plot consisted of four 6.1
m long rows spaced 90 cm apart. Seeds were planted on six dates starting
mid-Apr. to mid-Sept. Weeds were controlled mechanically. Plots were
irrigated as needed. Crop was harvested 40-44 days from planting. Before
harvest, height of five random plants per plot was measured. Two middle rows
were used in the yield estimations. Plants were harvested below first leaf
nodes and their fresh weight was taken. Dry weight was determined after drying
the plant material at 70°C in a forced air oven.
Field studies to identify culivars with maximum yield potential were carried
out during 1994 and 1995 summer seasons. Soil and other conditions of
production for these experiments were similar to the planting date experiments.
A total of nine accessions, eight supplied by Rodale Research Center as
potential vegetable type and one by the Plant Introduction Station, Ames, Iowa
were evaluated. The lay-out of experiments was randomized complete block
design with four replications. The plots were 6.1 m long with four rows spaced
90 cm apart. The accessions were planted in mid-June and harvested
approximately 40 days after germination. Five randomly selected plants were
collected at the time of harvest to measure growth parameters consisting of
branch number, leaf number, leaf area, stem and leaf fresh and dry weight.
Leaf area was measured with an area meter (LI-COR Model 3100, Lincoln,
Nebraska). Height of five random plants per plot was measured. Two middle
rows were used in the yield estimations. Fresh weight of the yield rows was
taken immediately after harvest. Dry weight was recorded after drying the
plant material at 70°C in a forced air oven. Leaf to stem ratios was
calculated.
Field studies from 1992-1994 were conducted to determine the effect of
different rates of N on the vegetative growth of amaranth. The soil and other
conditions of production were similar to other experiments. The genotype RRC
241 was used for seeding. The individual plots were 6.1 m long and four rows
wide. The experimental design was randomized complete block with four
replications. The N levels comprising the treatments were zero (control), 45,
90, and 135 kg/ha N. The N amount assigned to a plot was applied in split
application, half at germination and the other half two weeks later.
Harvesting and data collections for this study were similar to the cultivar
selection study.
Seeds planted in mid-Apr. failed to germinate (Table 1). In all plantings from
mid-May onwards, satisfactory amaranth germination was achieved. Mid-June
planting produced tallest plants with highest green and dry matter yield, while
these parameters were lowest for mid-Sept. planted seeds. The range for green
yield was 0.70-12.28 Mg/ha and the dry matter yield varied from 0.15-1.24
Mg/ha. The tallest and shortest plants measured 6.9 cm and 49.1 cm,
respectively.
Weather data for Apr. to Oct. during 1992 and 1993 indicate that amaranth seeds
needed soil temperature about 25°C to germinate and air temperature above
25°C for optimum growth. According to Wagoner (1983), most amaranth species
and cultivars germinate when the soil temperature reaches 18°C or above.
Webb et al. (1984) found that temperature around 25°C was optimal for
germination. Number of growing degree days during the growing season is a
major determinant of amaranth plant growth.
Green yield and dry matter yield of the nine plant accessions are presented in
Table 2. Out of nine accessions, six were A. tricolor, and one each
from A. hybridus, A. cruentus, and A. dubius. A. tricolor
is the choice vegetable amaranth type in Asia, while A. hybridus, A.
cruentus, and A. dubius are grown as vegetables in Greece, Africa,
and Caribbean and South America, respectively.
A. hybridus and A. cruentus accessions were taller than other
genotypes. A. dubius and A. tricolor accessions except PI 349553
were of similar height. A. tricolor accessions, RRC 389 and RRC 241 had
maximum number of leaves and leaf area, respectively. RRC 241 also had the
highest leaf fresh and dry weights. A. hybridus and A. cruentus
accessions had the highest stem fresh and dry weights, and green and dry matter
yields. RRC 241 produced maximum green yields among A. tricolor
accessions.
In comparing the green yield among A. tricolor, A. hybridus,
A. cruentus, and A. dubius species in Mississippi, Igbokwe et al.
(1988) also found A. hybridus to be highest yielding. Our finding of
A. cruentus producing higher green yields than A. tricolor does
not agree with Daloz (1981). Among A. tricolor accessions, Kauffman and
Gilbert (1981) and Makus and Davis (1984) have also reported RRC 241 to be top
performer. A. tricolor accessions, PI 349553 and RRC 241 had the
highest and A. cruentus and A. hybridus accessions, RRC 1034 and
RRC 843 had the lowest leaf : stem ratios. While both leaf and stem are
consumed in some parts of the world, plants with higher leaf : stem ratios are
more in demand. Campbell and Abbott (1982) have also reported higher leaf :
stem ratio in A. tricolor as compared to A. dubius and A.
cruentus.
There was a linear increase in plant height from N-fertilization (Table 3).
Leaf area increased with N-fertilization until 90 kg/ha. Stem and leaf fresh
and dry weights increased linearly with N-fertilization. Quadratic equations
provided the best fit for the green and dry matter yield. An R2 for
green yield of 0.70 as compared to 0.51 for the dry matter yield suggested that
a higher percentage of the increases in green yield as compared to the dry
matter yield could be attributed to N-fertilization probably as a result of an
increase in succulence.
The N needed for the growth of a crop will vary depending on the N status of
the soil and potential for mineralization. Therefore, optimum N amount
reported for maximum amaranth growth by different researchers are substantially
different. The reported range varies from 50-200 kg N/ha (Keskar et al. 1981;
Subhan 1989; Ramachandra and Thimmaraju 1983). All studies agree that
supplemental N is required for optimum amaranth yield.
The results suggested that for highest yields, amaranth should be seeded in
June. A. hybridus and A. cruentus produced significantly higher
green yield than A. dubius and A. tricolor. RRC 241 yielded the
highest among A. tricolor accessions. Nitrogen fertilization applied at
the rate of 90 kg/ha produced highest vegetable amaranth yields.
- Abbott, J.A. and T.A. Campbell. 1982. Sensory evaluation of vegetable amaranth
(Amaranthus spp.). HortScience 17:409-410.
- Berberich, S. 1980. Amaranth--a hot weather spinach substitute. Agr. Res.
29:15.
- Campbell, T.A. and J.A. Abbott. 1982. Field evaluation of vegetable amaranth
(Amaranthus spp.). HortScience 17:407-409.
- Daloz, C.R. 1981. Horticultural aspects of the vegetable amaranths. M.S.
thesis, Cornell Univ., Ithaca, NY.
- Huang, P.C. 1980. A study of the taxonomy of edible amaranth: an investigation
of amaranth both of botanical and horticultural characteristics. p. 142-150.
Proc. Second Amaranth Conf. Rodale Press, Emmaus, PA.
- Igbokwe, P.E., S.C. Tewari, J.B. Collins, J.B. Tartt, and L.C. Russell. 1988.
Amaranth--a potential crop for southern Mississippi. Res. Rep. Mississippi Agr.
Forestry Expt. Sta. 13(10):4.
- Kauffman, C.S. and L. Gilbert. 1981. Vegetable amaranth summary. Rodale Press,
Emmaus, PA.
- Keskar, B.G., D.P. Bhore, A.V. Patil, H.N. Sonone, and S.R. Maslekar. 1981.
Comparative efficacy of soil and foliar application of nitrogen through urea on
yield of leafy vegetable--Chaulai (Amaranthus blitum L.) at various seed
rates. J. Maharashtra Agr. Univ. 6:68-69.
- Makus, D.J. 1984. Evaluation of amaranth as a potential green crop in the
mid-south. HortScience 19:881-883.
- Makus, D.J. and D.R. Davis. 1984. A mid-summer crop for fresh greens or
canning: vegetable amaranth. Ark. Farm Res. 33:10.
- National Research Council (NRC). 1984. Amaranth: modern prospects for an
ancient crop. National Academy Press, Washington, D.C.
- Ramachandra, H.A. and K.R. Thimmaraju. 1983. Effect of different levels of
nitrogen and phosphorous on growth components and yield of Amaranthus
(Amaranthus gangeticus L.) cv. `A-25'. Mysore J. Agr. Sci. 17:158-164.
- Saunders, R.M. and R. Becker. 1984. Amaranthus: a potential food and
feed source. p. 357-396. In: Y. Pomeranz (ed.), Advances in cereal science and
technology. Vol. 6. Am. Assoc. Cereal Chem., St. Paul, MN.
- Sealy, K.L., E.L. Mcwilliams, J. Novak, F. Fong, and C.M. Kenerly. 1990.
Vegetable amaranth: cultivar selection for summer production in the south. p.
396-398. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber
Press, Portland, OR.
- Singh, B.P. and W.F. Whitehead. 1991. Performance of amaranth at six in-row
plant densities. HortScience 26:708(Abstr.).
- Singh, B.P. and W.F. Whitehead. 1993. Population density and soil pH effects on
vegetable amaranth production. p. 562-564. In: J. Janick and J.E. Simon (eds.),
New crops. Wiley, New York.
- Stallknecht, G.F. and J.R. Schulz-Schaeffer. 1993. Amaranth rediscovered. p.
211-218. In: J. Janick and J.E. Simon (eds.), New crops. Wiley, New York.
- Subhan. 1989. Effect of dosage and application time of nitrogen fertilizer on
growth and yield of amaranth (Amaranthus tricolor L.) (Indonesian,
English summary). Penelitian Hortikultura 17:31-40.
- Teutonico, R.A. and D. Knorr. 1985. Amaranth: composition, properties and
applications of a rediscovered food crop. Food Tech. 39:49-60.
- Tucker, J.B. 1986. Amaranth: the once and future crop. BioScience 36:9-13,
59-60.
- Wagoner, P. 1983. Summary of the grain amaranth time of planting trials. Report
NC-84/30. Rodale Press, Emmaus, PA.
- Webb, D.M., J.R. Schaeffer, and C.W. Smith. 1984. Screening of grain amaranth
for adaptation to Montana, USA. p. 201-211. Proc. Third Amaranth Conf. Rodale
Press, Emmaus, PA.
- Willis, R.B.H., A.W.K. Wong, F.M. Scriven, and H. Greenfield. 1984. Nutrient
composition of Chinese vegetables. J. Agr. Food Chem. 32:413-416.
Table 1. Plant height, green yield, and dry matter yield of amaranth at
six planting datesz.
| Planting dates | Plant height
(cm) | Green yield
(Mg/ha) | Dry matter yield
(Mg/ha) |
| Apr. 12 | 0dy | 0.0d | 0.00e |
| May 12 | 18c | 1.9bcd | 0.33cd |
| June 15 | 49a | 12.3a | 1.24a |
| July 14 | 35b | 4.1b | 0.62b |
| Aug. 15 | 30b | 3.6bc | 0.59bc |
| Sept. 14 | 7d | 0.7cd | 0.15de |
z1992 and 1993 experiments combined.
yMean separation within column by Duncan's multiple range test, P =
0.05.
Table 2. Vegetative growth parameters and yield of nine amaranth
accessionsz.
|
| Plant weight (g/plant) |
|
| Stem | Leaf |
| Accession number | Species | Plant height (cm) | Leaf number (no./plant) | Leaf area (cm2/plant) | Fresh | Dry | Fresh | Dry | Leaf:stem ratio | Green yield (Mg/ha) | Dry matter yield (Mg/ha) |
| Hinchoy GL | A. tricolor | 40by | 89bc | 1336bc | 65b | 6.3bc | 58bc | 10.4b | 0.90b | 7.3bc | 0.91de |
| RRC 389 | A. tricolor | 48b | 133a | 1362bc | 65b | 7.4b | 52bcd | 9.2bc | 0.82b | 7.4bc | 0.96de |
| RRC 701 | A. tricolor | 46b | 75cd | 1069cd | 56bc | 5.7bc | 46cd | 9.0bc | 0.84b | 6.9c | 1.00cd |
| RRC 843 | A. hybridus | 72a | 91bc | 1351bc | 112a | 10.2a | 67ab | 11.7ab | 0.61c | 11.9a | 1.37ab |
| RRC 1034 | A. cruentu | 67a | 105b | 1308bc | 104a | 10.3a | 69ab | 12.2ab | 0.68c | 11.1a | 1.40a |
| RRC 1186 | A. dubius | 43b | 76cd | 1350bc | 51bc | 4.8bc | 56bcd | 9.6bc | 1.12a | 8.4bc | 1.10bcd |
| Hinchoy VL | A. tricolor | 45b | 80cd | 1503ab | 72b | 7.3b | 64ab | 12.0ab | 0.93b | 6.9c | 0.96de |
| PI 349553 | A. tricolor | 30c | 64d | 910d | 34c | 3.7e | 40d | 7.2c | 1.16a | 4.3d | 0.69e |
| RRC 241 | A. tricolor | 43b | 93bc | 1819a | 70b | 6.6b | 78a | 13.8a | 1.14a | 9.2b | 1.25abc |
z1994 and 1995 experiments combined.
yMean separation within column by Duncan's multiple range test, P =
0.05.
Table 3. Vegetative growth parameters and yield of amaranth at four
N-fertilization ratesz.
|
| Plant weight (g/plant) |
|
| Stem | Leaf |
| N-rate (kg N/ha) | Plant height (cm) | Leaf number (no./plant) | Leaf area
(cm2/plant) | Fresh | Dry | Fresh | Dry | Leaf:stem ratio | Green yield (Mg/ha) | Dry matter yield (Mg/ha) |
| 0 | 30 | 57 | 1013 | 37 | 3.2 | 53 | 7.6 | 1.50 | 5.5 | 0.83 |
| 45 | 33 | 71 | 1484 | 47 | 4.5 | 64 | 9.9 | 1.45 | 8.8 | 1.21 |
| 90 | 36 | 71 | 1766 | 66 | 5.4 | 82 | 10.2 | 1.33 | 12.0 | 1.57 |
| 135 | 39 | 82 | 1705 | 74 | 6.3 | 85 | 11.1 | 1.18 | 12.6 | 1.53 |
| Significance | L** | L** | Q* | L** | L** | L** | L** | L** | Q** | Q* |
z1992, 1993, and 1994 experiments combined.
*, ** Significant at P = 0.05 (*) or 0.01 (**) level.
Last update June 24, 1997
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