Adventitious roots in mung bean [Vigna radiata (L.) R. Wilcz. cv. Berken] cuttings develop from specific “rooting-zone parenchyma” (R-ZP) cells. Microautoradiography was used to determine the timing of thymidine and uridine incorporation into the R-ZP cells, prior to the first cell division, in the presence or absence of naphthaleneacetic acid (NAA). Since 6-3H-thymidine incorporation reached a maximum between 11 and 14 hours, we suggest that the R-ZP cells were in the G1 phase when the cuttings were taken. Tritiated uridine was incorporated into the RNA of the R-ZP cells 2 hours after the cuttings were placed in the labeled solution. DNA synthesis and cell division of the R-ZP cells occurred along the entire length of the hypocotyl (basal, middle, and top segments), but these initial events were not sufficient to result in the subsequent formation of adventitious roots. NAA promoted adventitious root formation in the cuttings but it had no apparent effect on nucleic acid labeling nor initial cell division of the R-ZP cells. The initial division of the R-ZP cells appears to be a wounding response and occurs in the presence or absence of exogenous auxin.
Interspecific hybridization between Vigna radiata and V. angularis is reported for the first time. Two hybrids developed from embryos which were excised from immature seeds of V. radiata and cultured on artificial medium. The plants flowered early and continuously until death. No seeds were produced. Mean pairing at metaphase I was 2.39II + 17.22I (2n = 22).
Ethylene liberated from control and auxin-treated cuttings of Vigna radiata (L.) R. Wilcz cv. Berken was monitored for 14 hours. For root initiation, naphthaleneacetic acid (NAA) and indolebutyric acid (IBA) were the most effective with indoleacetic acid (IAA) intermediate and 2,4-dichlorophenoxyacetic (2,4-D) the least effective. No correlation was observed between the quantity of auxin-induced ethylene evolved and the number of roots formed. Decreasing the NAA solution pH from 7.0 to 3.0 reduced the evolution of ethylene but did not alter the rooting response of the cuttings. It was concluded that stimulation of adventitious root initiation by auxin is not mediated by ethylene.
Adventitious root initiation decreased in ‘Berken’ mung bean cuttings treated with ≥ 10−4 m (2-chloroethyl) phosphonic acid (ethephon). Ethephon at 10−3 but not 10−5 m reduced root length and caused a redistribution of roots along the hypocotyl. The application of ethephon in combination with indoleacetic acid (IAA), indolebutyric acid (IBA), naphthaleneacetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D) reduced root initiation. An initial treatment of ethephon followed by NAA, or NAA followed by ethephon, inhibited root initiation to the same degree. Ethephon—whether applied at the time of cutting preparation or up to 12 hours later—inhibited root initiation to the same extent.
The objective of this research was to evaluate the effects of vacuum cooling and temperature on the quality and storage life of mung bean sprouts (Vigna radiata L. Wilczek). Sprouts in micro-perforated bags were either not precooled or vacuum cooled to 9, 6, or 3 °C, and stored for 7 days at 1, 3, or 6 °C. Vacuum-cooled bean sprouts lost more weight than sprouts not precooled, and the weight loss was greater when the sprouts were cooled to lower temperatures. However, the total loss never exceeded 5% and no apparent signs of shrivel were observed. Vacuum cooling resulted in greater product freshness after 4 days of storage, but the effect was nonsignificant after 7 days. Storage temperature had greater influence on bean sprout quality than did cooling temperature, with greater freshness and whiter hypocotyls at the lower temperatures. However, blackening of cotyledons increased as the storage temperature decreased.
Seeds of `Berken' mung bean [Vigna radiata (L.) R. Wilcz.] were surface-sterilized with NaOCl and then either aerated 24 hours before sowing (routine procedure), planted immediately after the NaOCl treatment, or treated with hot cupric acetate and antibiotics before planting. Nine- or 10-day-old seedlings were used in rooting bioassays. Up to 10% of the seedlings and 17% of the cuttings had collapsed upper stems or wilted leaves. None of the seed treatments completely eliminated the pathogen, but the combination of hot cupric acetate plus antibiotics reduced the quantity of diseased cuttings to 3.3%. A white and two yellow-pigmented (Y1 and Y2) bacteria were isolated from diseased cuttings and used in subsequent pathogenicity tests. The Y2 strain was nonpathogenic. Stems of plants inoculated with the white strain turned brown and collapsed 2 days after inoculation, whereas leaves of plants inoculated with the Y1 strain wilted after 7 days. Electron microscopy, fatty acid analysis, and standard biochemical and physiological tests were used to identify the white strain as Pseudomonas syringae pv. syringae van Hall and the Y1 strain as Curtobacterium flaccumfaciens ssp. flaccumfaciens (Hedges) Collins and Jones. These results emphasize that seeds of mung bean should be checked for seedborne pathogens to avoid experimental artifacts.
The performance of the mung bean cultivar Thai Green Oil was compared with the soybean cutivar Hsih-Hsih over a range of 12 plant densities from 10,000 to 800,000 plants/ha. Increasing plant density was positively related to yield and plant height and negatively related with significant reductions in flowering, yield per plant and plant branching. The higher yield potential of soybeans at high plant densities, relative to mung bean, was attributed to differences in the production of the number of flowers per plant and, subsequently, the number of pods per plant. This relationship can be applied to breeding and selecting improved mung bean cultivars.
increases in light interception, energy conversion, and partitioning efficiencies J. Expt. Bot. 65 3311 3321 Nair, R.M. Yang, R. Easdown, W.J. Thavarajah, D. Thavarajah, P. Hughes, J. Keatinge, J.D.H. 2013 Biofortification of mungbean ( Vigna radiata ) as a
Methods Two experiments were performed in which seeds of three vegetable species, broccoli ( Brassica oleracea) , onion ( Allium cepa ), and mung bean ( Vigna radiata) , were germinated until they reached an “edible sprout” size. This size is dependent on
growth conditions. Seeds of Vigna radiata cv. Tainan No. 5 (TN5), a chilling-sensitive cultivar, were purchased from the local (Pu-Tze Township) farmers' association. Seeds were germinated in pots containing a 1 perlite : 1 vermiculite : 1 peat (by