Even though mothbean (Vigna aconitifolia), a drought- and heat-tolerant crop, may have potential in the eastern United States, information about its production in this region is not available. To characterize potential seed yields and preliminary nutritional quality, 54 accessions were grown near Petersburg, VA, during 2011, 2012, and 2013. The seed yields varied from 48 to 413 lb/acre. The mean concentrations of protein, calcium, iron, and zinc in mature mothbean seed were 21.9%, 0.17%, 64.8 ppm, and 37.5 ppm, respectively. These values compared well with those in mungbean (Vigna radiata) and tepary bean (Phaseolus acutifolius). The results demonstrated that mothbean has considerable potential as an alternative, new food legume crop in Virginia and eastern United States.
A description for the design and use of a flowing solution culture for the mung bean bioassay is presented. A single module for the system is an assembly of polyvinyl chloride (PVC) pipe, Tygon tubing, and 12 hypodermic syringe barrels to accomodate 60 cuttings of mung bean, Vigna radiata (L.) R. Wilcz, (5 per syringe barrel). Solution is circulated by an electric fluid pump. A comparison of this system with conventional vial culture indicates no difference in mean root numbers and their standard deviation, although a more stable solution pH is maintained in the flowing system. In the vial system, pH drifted by as much as 1.4 units within 12 hours, but only 0.2 units in the flowing system. The system presented is ideal for investigations where a stable rooting environment is required.
The distribution of 14C-photosynthates was examined in pot-grown Tainan-1 mung bean plants (Vigna radiata (L.) Wilczek var. radiata). Whole plants were assimilated with 14CO2 at anthesis, and at 7 and 17 days after anthesis. The 14C-photosynthate fixed at anthesis was retained mostly in the vegetative tissue. However, of the 14C-photosynthate fixed at early pod development stage (i.e. 7 days after anthesis), 15-26% of the assimilated 14C was detected in the reproductive tissue within 24 hours after exposure, whereas about 43% was detected at maturity (i.e. 38 days after anthesis). When plants with full grown pods (i.e. 17 days after anthesis) were treated, 70% of the 14C was detected in the reproductive tissue 24 hours after exposure and at maturity.
Field tests were conducted in commercial mung bean (Vigna radiata) fields in 1986, 1987, and 1989. The objective of these tests were to: determine optimum nitrogen fertilizer rates; evaluate preplant, postemergence or split applications of nitrogen; and develop data to utilize petiole sampling as an analytic technique to quantify plant nitrogen status.
Seed yields were significantly increased two of the three years by the addition of nitrogen fertilizers. Over three years, the addition of 40-120 pounds of nitrogen per acre resulted in an average seed yield increase of 14-37 percent, compared to an untreated control. Maximum yields were obtained with eighty pounds of nitrogen per acre. Within specific rates, there was a trend for preplant or split applications to result in the greatest yield increases.
Petiole nitrate levels did not appear to be a reliable indicator of plant nitrogen status, with wide differences between rates in different years. An average for the three-year test, six weeks after crop emergence, was 1270 ppm for the control and 2340 ppm for treatments receiving 80 pounds of nitrogen per acre.
The effectiveness of using moving mean covariance analysis (MMCA) rather than randomized complete-block design (RCBD) in experimental error control was compared in a large-scale mungbean [Vigna radiata (L.) Wilczek] yield trial. The MMCA was superior to the RCBD, since it significantly reduced the experimental error and the coefficient of variation (cv). Inclusion of five neighboring plots in the moving mean computation provided better error control. However, the estimation of optimum number of neighboring plots to be used and moving mean calculations were tedious. The feasibility of using border-row measurements such as mean plant height at 50% flowering or mean seed yield/m of row as a covariate in an analysis of covariance (BRMCA) was examined in a separate mungbean yield trial in which border rows were planted with a check cultivar. Both border-row measurements were equally effective in reducing the experimental error. However, plant height measurements were simpler than measuring seed yield. Because border-row measurements could be readily used as covariate in analysis of covariance without a need for moving mean computation from the response variable, BRMCA could be advantageous for error control in row crops yield evaluation.
Mung bean (Vigna radiata L.) is one of the economically important crops in Southeastern Asia and also grows in USA. Genetic transformation of mung bean has been achieved using an Agrobacterium -mediated transformation system. Two transformation methods were used in this study. With the leaf-disk transformation method, freshly cut leaf strips from young seedlings of mungbean were co-cultivated for 72 hours with either a wild-type A. rhizogenes strain 11325 or the strain containing an additional binary vector carrying the npt gene. In another method, agrobacteria were applied to wounded hypocotyls of aseptically germinated seedlings. After infection, the explants were placed on shoot induction medium. Within 3-4 weeks, shoots developed from the edges of leaf disks as well as from the inoculated sites on hypocotyls. Putatively transformed shoots were selected in vitro based on their ability to root in the kanamycin-containing medium. The npt gene fragment and a-few of T-DNA fragments from the wild-type Ri plasmid were detected in regenerated mungbean plants by Southern blot analysis. These results suggested that foreign DNAs from both the Ri plasmid and the binary vector had integrated into the genome of mung bean. These transformation systems for mung bean can now be used to introduce agronomically desirable traits into this crop for its genetic improvement.
Tonoplast vesicles isolated from juice cells of mature `Valencia' oranges [Citrus sinensis (L.) Osbeck] showed similar tonoplast-bound vacuolar ATPase (V-ATPase) and inorganic pyrophosphatase (V-PPiase) activity as measured by product formation. Both proton pumps were able to generate a similar pH gradient, although steady-state was reached faster with ATP as substrate. When a ΔpH of 3 units was imposed (vesicle lumen pH of 4.5 and incubation medium of 7.5), tonoplast-bound PPiase was not able to significantly amplify the existing ΔpH. Although not able to function as a H+ pump, V-PPiase effectively synthesized PPi in the presence of inorganic phosphate (Pi). Formation of PPi by V-PPiase was enhanced by ATP but inhibited by NaF, gramicidin, and by antibodies raised against V-PPiase from mung bean [Vigna radiata (L.) R. Wilcz. (Syn. Phaseolus aureus Roxb.)]. Immunological analysis demonstrated an increase in V-PPiase protein with fruit maturity. Data indicate that under in vivo conditions, the V-PPiase of mature orange juice cells acts as a source of inorganic pyrophosphate (PPi) but not as a H+ pump. We propose that synthesis of PPi provides a mechanism for recovery of stored energy in the form of the pH gradient across the vacuole during later stages of development and postharvest storage.
Mung bean (Vigna radiata (L.) R. Wilcz.) cuttings are used in rooting bioassays, and nonexperimental variability must be rigorously controlled to obtain meaningful results. This study was conducted to document bacterial disease problems of mung bean and identify the causal organisms. `Berken' seeds were surfaced sterilized and aerated 24 hr before sowing. Nine-day-old seedlings were used in rooting bioassays. Up to 10% of the seedlings and 17% of the cuttings had collapsed stems or wilted leaves. A white and two yellow (Y1 and Y2) bacteria were isolated from diseased cuttings and used in subsequent pathogenicity tests. The Y2 isolate was nonpathogenic. Stems of healthy mung beans inoculated with the white isolate turned brown and collapsed 2 days after inoculation, whereas leaves of plants inoculated with the yellow isolate wilted after 7 days. Standard biochemical and physiological tests revealed that the white isolate was Pseudomonas syringue pv. syringae van Hall and the yellow isolate was Curtobacterium flaccumfaciens subsp. flaccumfaciens (Hedges) Collins and Jones. This research is the first report of a disease in mung bean caused by P.s. pv. syringae. These results demonstrate the need or disease-free seeds being used in bioassays since both pathogens were seed-borne.
Adventitious root formation (rooting) in `Berken' mungbean [Vigna radiata (L.) Rwiclz.] cuttings is stimulated by indole-3-acetic acid (IAA). To understand the molecular events that occur during IAA-induced adventitious root initiation, a λgt11 cDNA library was made from mungbean hypocotyls treated with 500 μm IAA for 3 hours and differentially screened. Two cDNAs MII-3 and MII-4 were isolated. Southern analysis revealed that both cDNAs are encoded by different genes. Expression studies showed different patterns for both genes. Both MII-3 and MII-4 were highly expressed in IAA treated hypocotyls, whereas MII-4 was also induced in IAA treated epicotyls. There was no expression of either MII-3 or MII-4 in control or IAA treated leaves. With increasing concentrations of IAA from 100 to 1000 μm there was an increase in the average root number per cutting as well as a stimulation in MII-3 and MII-4. Both MII-3 and MII-4 showed a stimulation in expression 4 hours following treatment with 500 μm IAA reaching a maximum from 4 to 8 hours followed by a decline thereafter. Basal expression of MII-3 was evident between 2 and 8 hours, whereas, a high degree of basal expression was found with MII-4 from 1 to 8 hours followed by a sharp decline. Cycloheximide (50 μm) dramatically reduced rooting and MII-3 expression, whereas MII-4 was only slightly affected.
Knowledge of the type and extent of the genotype × environment (G × E) interaction on a particular crop can be applied to improve the efficiency of resource allocation in long-term yield trials. Estimates of the relative magnitude of G × E, for seed yield and related traits, were obtained from mungbean [Vigna radiata (L.) Wilczek] field trials conducted at the Asian Vegetable Research and Development Center (AVRDC) in Taiwan. Ten diverse genotypes were evaluated in spring, summer, and fall during 2 years. Photoperiod, temperature, and distribution of pest and diseases vary distinctly during these seasons. The