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Johnson, H.E., M. Hegsted, and W.J. Blackmon. 1990. Protein quality evaluation of Apios americana tubers. p. 443. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.

Protein Quality Evaluation of Apios americana Tubers

Holly E. Johnson, Maren Hegsted, and William J. Blackmon

Apios americana Medikus (apios) is a nitrogen-fixing legume, which produces both seeds and tubers. The tubers contain a crude protein content of 12-13% on a dry wt basis. Methionine, cysteine, and isoleuceine are the limiting amino acids, but some of the cysteine could have been lost in the hydrolysis reaction of the assay procedure. Metabolic feeding studies with rats indicate apparent protein digestibility of 81.2±2.4 for 100% boiled apios (BA) and 42.3±3.4 for a 50:50 mixture of casein:raw apios (C/RA). Protein digestibility of RA alone could not be determined due to poor food consumption and weight loss by the rats. Apparent biological value was 89.2±9.8 for the 100% BA, and -81±13.1 for the 50:50 C/RA. Feed efficiency for the 100% BA was .59±.73 and -16±1.6 for 50:50 C/RA diets. Pancreatic hypertrophy of the rats consuming the RA indicates a high level of protease inhibitors. Cholesterol levels were decreased in animals consuming RA, however, hemoglobin and hematocrit levels were not affected by the presence of apios in the diets. Cooked tubers consistently performed better than raw tubers, suggesting the necessity of cooking tubers for use as a food source.

Wilson, P.W., F.J. Pichardo, W.J. Blackmon, and B.D. Reynolds. 1990. Protein quality in Apios americana tubers and seeds. p. 443. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.

Protein Quality in Apios americana Tubers and Seeds

P.W. Wilson, F.J. Pichardo, W.J. Blackmon, and B.D. Reynolds

The proteins in Apios americana were studied in terms of total nitrogen, true protein nitrogen, biuret protein, total amino acids, and in vitro digestibility. Seeds contained an average of 4.83% total nitrogen on a dry defatted basis, which would indicate 30.2% crude protein (N x 6.25). However, the non-protein nitrogen after precipitation with trichloroacetic acid was 1.18%, indicating less "true" protein and only 25.17% protein was found using the biuret method. Using ion-exchange chromatography, the predominant amino acid was found to be glutamic acid (79.67 g/100 g N) followed by aspartic acid (56.97 g/100 g N). The percent of in vitro digestibility for seed protein was 72.2. The computed protein efficiency ratio (C-PER) of A. americana seeds was 0.99.

Tubers contained an average of 2.12% total nitrogen on a dry defatted basis (indicating 13.25% crude protein) with 0.48% as non-protein nitrogen. The biuret protein content of tubers was found to be 13.99%. The predominant amino acid in tubers was aspartic acid (79.54 g/100 g N) followed by glutamic acid (47.48 g/100 g N). In vitro digestibility of the tubers was 69.9%.

Picha, D.H., W.J. Blackmon, P.W. Wilson, L.P. Hanson, and B.D. Reynolds. 1990. Compositional changes in Apios americana tubers during storage. p. 443. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.

Compositional Changes in Apios americana Tubers During Storage

D.H. Picha, W.J. Blackmon, P.W. Wilson, L.P. Hanson, and B.D. Reynolds

The tubers of the perennial legume Apios americana Medikus, line LA85-034, were monitored for changes in dry matter, alcohol-insoluble solids (AIS) and ethanol soluble sugar under different storage regimes. Tubers left in the ground after frost-kill of the above-ground vine exhibited little or no compositional changes when harvested at monthly intervals from December to March. Tuber dry matter, AIS, and sucrose concentration decreased during April and May, which corresponded with sprout emergence and growth. Non-sprouted tubers were high in dry matter (47-50%), high in AIS (39-42%), and low in fructose, glucose, and maltose (<0.10% fresh wt. of each sugar). Only a slight loss in dry matter and AIS occurred in tubers stored over a 15 week period at 4°C or 16°C. Sucrose, the major sugar, increased in concentration from 1.4% to 2.0% during the first 5 weeks of storage at 16°C, after which it remained stable over the next 10 weeks. Sucrose synthesis was enhanced at 4°C storage, with a maximum of 3.2% accumulating after 10 weeks. No noticeable symptoms of chilling injury existed after 15 weeks storage at 4d°C.

Putnam, D.H., L. Field, and G.H. Heichel. 1990. Inoculation, nitrogen, and cultivar effects on nodulation and tuber yield of Apios americana. p. 444. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.

Inoculation, Nitrogen, and Cultivar Effects on Nodulation and Tuber Yield of Apios americana

D.H. Putnam, L. Field, and G.H. Heichel

Apios americana Medikus (groundnut) is an edible wild tuberous legume native to the eastern half of North America, and has been proposed as an alternative specially tuber crop. Accessions of Apios were grown in the greenhouse and field to assess nodulation, N-requirement, tuber yield and quality. Tuber dry weight was doubled with the addition of 100 ppm nitrogen in frequent watering or with inoculation with a common soybean rhizobial strain. Nodule weight and number were increased significantly by inoculation. Greenhouse and field tuber yields differed according to accession. Most accessions overwintered in Minnesota and produced harvestable yields only in the second year. Significant biological impediments remain to the production of Apios in this environment. These are viney growth habit, lack of effective weed control lack of well adapted cultivars, insect problems, and low yields.

Wells, D.W., R.J. Constantin, W.J. Blackmon, and B.D. Reynolds. 1990. Evaluations of preemergence herbicides for use in Apios americana. p. 444. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.

Evaluations of Preemergence Herbicides for Use in Apios americana

D. Wayne Wells, R.J. Constantin, William J. Blackmon, and Berthal D. Reynolds

Selected preemergence herbicides were tested for use in the culture of Apios americana (apios) planted as seeds, transplants in peat pellets, and whole tubers. Herbicide applications were made to transplanted plots prior to planting and to seeded and whole tuber plots after planting. The soil type was a Cahaba fine sandy loam with 0.45% organic matter and 5.5 pH. Apios tolerance to herbicides was associated with planting methods. When planted as seeds, the emerging seedlings appeared to be very prone to herbicidal injury, however, seedling diseases and insect damage prevented definitive evaluations. Mean injury ratings for transplant and tuber plots five weeks after treatment were as follows:

Percent injury
Treatment Rate kg ai/ha transplants tubers
alachlor 2.24 14 3
benefin 1.12 0 0
bensulide 5.60 0 0
cinmethylin 2.24 14 4
diethatyl ethyl 3.36 4 4
ethiozin 1.68 100 0
linuron 1.68 30 3
metolachlor 1.68 3 5
napropamide 4.48 1 28
oryzalin 0.84 0 3
trifluralin 0.84 0 4
bensulide 4.48
" +clomazone 1.22 60 1
The major weed species were crabgrass (Digitaria spp.), goosegrass (Eleusine indica), broadleaf signalgrass (Brachiaria platyphylla), corn spurry (Spergula arvensis), purslane (Portulaca oleracea), pigweed (Amaranthus spinosus), and annual sedge (Cyperus iria).

Weed control was only poor to fair with benefin, bensulide, napropamide, and oryzalin treatments. Other treatments exhibited good to excellent control for at least some of the weed species present. Reduced weed control was observed when apios was established from transplants, probably as a result of soil disturbance after herbicide applications.

Musgrave, M.E., A.G. Hopkins, Jr., and W.J. Blackmon. 1990. Evaluating Apios americana as a wetland tuber crop. p. 445. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.

Evaluating Apios americana as a Wetland Tuber Crop

Mary E. Musgrave, Alston G. Hopkins, Jr., and William J. Blackmon

Apios americana Medikus (apios) is a tuber-producing, viny legume whose natural habitat is characterized by waterlogged soils; however, domestication efforts have focused on evaluating germplasm on well-drained sites. Some evidence suggests that tolerance to low oxygen imposed by waterlogging is associated with the differential activity of respiratory pathways. Among many cultivated tuber and root crops, the respiration in freshly-sliced storage tissue is generally cyanide-sensitive but acquires a cyanide-resistant component as the tissue slices age. Two lines, LA85-034 and LA85-006 were selected to evaluate respiration patterns. Apios produces tubers on strings along its underground stem (rhizome). LA85-034 which produces large, single-node tubers exhibited respiration similar to that typical of Irish potato and many other storage crops. In contrast, LA85-006 manifested a large component of cyanide-resistant respiration in freshly sliced tubers. This line produces small multinode tubers. Rhizome respiration in both lines was highly cyanide-resistant.

Since cyanide-resistant respiration has been related to waterlogging tolerance, these two lines are being compared in their response to waterlogging. Tubers of LA85-006 grew well (82% sprouted) underwater while those of line LA85-034 did not sprout (6%) and would not continue to grow even if presprouted prior to submergence. These two lines were established in the field and are being evaluated in their response to longterm waterlogging. Laboratory tests suggest that there may be considerable variation within apios germplasm with regard to waterlogging tolerance and that initial selection schemes could influence its success as a potential wetland tuber crop. Conventional crop plants are unable to tuberize under anoxic conditions so the ability of apios to tuberize in waterlogged sites is of interest.

Venketeswaran, S., M.A.D.L. Dias, and U.V. Weyers. 1990. The winged bean: A potential protein crop. p. 445. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.

The Winged Bean: A Potential Protein Crop

S. Venketeswaran, M.A.D.L. Dias, and Ursula V. Weyers

The winged bean, Psophocarpus tetragonolobus (L) D.C. is a member of the Legume family and is a tropical plant found chiefly in rural areas of Papua, New Guinea and Southeast Asia. It grows abundantly in hot, humid equatorial countries such as Indonesia, Malaysia, Thailand, Philippines, India, Bangladesh, Burma and Sri Lanka. Although at one time considered as a "poor man's food", the potential economic importance of the plant has attracted world-wide attention and is now recognized as "A High Protein Crop for the Topics".

The winged bean plant grows as a vine with climbing stems and leaves, 3-4 m in high. It is a herbaceous perennial; but can be grown generally as an annual. Although there are several cultivars with wide differences in physical features and in physiology, the plant produces an abundance of leaves and inflorescences of white, blue, deep purple or pink flowers which quickly develop into pods. The pods are 4-sided with fringed wings and can be 6-30 cm in length and consisting of 5-20 seeds per pod. The seeds which are rich in protein are comparable to soybean in composition and nutritional value and contain similar proportions of protein (30-40%), carbohydrates, oil (15-20%), minerals, vitamins, essential amino acids and other constituents. Besides the various economical and industrial uses of seeds for commercial exploitation, they are also useful as food when steamed, boiled, fried, roasted, fermented, made into milk and other methods. The plant also produces underground tubers of varying sizes, rich in carbohydrates (25-30%) and proteins (10-15%). The plant is one of the best nitrogen fixers with nodulation accomplished by soil bacterium, Rhizobium. Because of its ability to fix nitrogen from the atmosphere, the plant requires very little or no fertilizers.

Callus tissue and suspension cultures of the winged bean can be established in a salt-sucrose culture medium supplemented with various combinations of auxins, viz., 2, 4-dichlorophenoxyacetic acid (2,4-D), naphthaleneacetic acid (NAA) + kinetin and/or 6-benzylaminopurine (BA). Regeneration of plantlets can be achieved via organogenesis or somatic embryogenesis.

Rhoden, E.G., C.K.Bonsi, and M.L. Ngoyi. 1990. Effect of southern root knot nematode on yield components of yardlong beans. p. 445. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.

Effect of Southern Root Knot Nematode on Yield Components of Yardlong Beans

E.G. Rhoden, C.K.Bonsi, and M.L. Ngoyi

The influence of different levels of root knot nematode populations on yield and yield components of yardlong beans [Vigna sesquipedalis (L.) Fruw.] under greenhouse conditions was investigated. Plants were inoculated with 0, 5,000 or 7,500 larvae of Meloidogyne incognita per 500 ml of soil. Root knot nematodes reduced seed yield. Plants not inoculated produced 15.97 grams of seeds while those grown in 5,000 or 7,500 larvae per 500 ml soil produced 6.39 and 6.75 grams per plant, respectively. Inoculated plants flowered later, had lower shellout percent and less seeds per pod than the controls. The control plants had more pods per plant (6.80 vs. 4.60 and 4.25) than the inoculated plants. Nematode inoculation also caused a significant decrease in the total pod yield of yardlong beans. Plants grown without nematodes produced 22.31 grams while those inoculated with 5,000 or 7,500 larvae per 500 ml soil produced 9.20 and 9.66 grams of pod per plant respectively

Rhoden, E.G., C.K. Bonsi, and M.L. Ngoyi. 1990. Susceptibility of yardlong beans to root knot nematode infestation. p. 445. In: J. Janick and J.E. Simon (eds.), Advances in new crops. Timber Press, Portland, OR.

Susceptibility of Yardlong Beans to Root Knot Nematode Infestation

E.G. Rhoden, C.K. Bonsi, and M.L. Ngoyi

Yardlong bean [Vigna sesquipedalis (L.) Fruw] plants grown in the greenhouse were inoculated with Meloiidogyne incognita inoculum at the rates of 0, 5,000 and 7,500 larvae per 500 ml of soil. Increase in nematode population resulted in a significant increase in the number of eggs per gram of root fresh weight. Plants inoculated with 7,500 larvae per 500 ml of soil tended to have greater root volume and dry weight. Although control plants were taller than those inoculated with M. incognita at anthesis, these differences were not significant. Plants inoculated with either the low or high levels of nematode had significantly higher gall and egg mass indices. Plant dry weight was significantly reduced by nematode infestation. Yardlong beans appeared to be susceptible to M. incognita.
Last update March 18, 1997 by aw