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91.
Morphologically normal and fertile transgenic plants of mungbean with two transgenes, bar and α-amylase inhibitor, have been developed for the first time. Cotyledonary node explants were transformed by cocultivation
with Agrobacterium tumefaciens strain EHA105 harboring a binary vector pKSB that carried bialaphos resistance (bar) gene and Phaseolus vulgaris α-amylase inhibitor-1 (αAI-1) gene. Green transformed shoots were regenerated and rooted on medium containing phosphinothricin (PPT). Preculture and
wounding of the explants, presence of acetosyringone and PPT-based selection of transformants played significant role in enhancing
transformation frequency. Presence and expression of the bar gene in primary transformants was evidenced by PCR-Southern analysis and PPT leaf paint assay, respectively. Integration
of the Phaseolus vulgaris α-amylase inhibitor gene was confirmed by Southern blot analysis. PCR analysis revealed inheritance of both the transgenes
in most of the T1 lines. Tolerance to herbicide was evidenced from seed germination test and chlorophenol red assay in T1 plants. Transgenic plants could be recovered after 8–10 weeks of cocultivation with Agrobacterium. An overall transformation frequency of 1.51% was achieved. 相似文献
92.
Mohamed Benichou Gracia Martinez-Reina Felix Romojaro Jean-Claude Pech Alain Latché 《Physiologia plantarum》1995,94(4):629-634
A 36-kDa 1-aminocyclopropane-1-carboxylate (ACC) N-malonyltransferase, which converts the ethylene precursor ACC into the conjugated derivative malonyl-ACC (MACC), has been isolated from etiolated mung bean ( Vigna radiata ) hypocotyls, and partially purified in a four-step procedure. The enzyme is stimulated about 7-fold by 100 m M K+ salts or 0.5 m M Co2+ salts, and is inhibited competitively by D-phenylalanine (Ki = 1.3 m M ) and non competitively by CoASH (0.3 m M ). Beside malonyl-CoA, it is capable to use succinyl-CoA as an acyl donor. The 36-kDa enzyme described here exhibits a lower optimum temperature (40°C) and a 7- or 3-fold lower apparent Km for ACC (68 μ M ) and malonyl-CoA (74 μ M ), respectively, when compared with its 55 kDa isoform already isolated from the same plant material. This data support the idea that several isoforms of ACC N-malonyltransferase exist in plants. These isoforms may play a differential role in regulating the availability of ACC, and consequently the rate of ethylene production, as well as detoxifying cells from D-amino acids. 相似文献
93.
94.
95.
Frank J. Messina Michelle Mendenhall & Jake C. Jones 《Entomologia Experimentalis et Applicata》2009,132(1):39-49
Many insects use a fairly well-defined set of host plants, but are occasionally observed on an atypical host. The seed beetle Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchinae) has rarely been reported to attack lentil, which is distantly related to its usual legume hosts. An initial assay of an Asian beetle population revealed that none of the 100 larvae entering lentil seeds survived to adult emergence. Nevertheless, three attempts at mass selection, in which more than 2 000 adults were added to lentil seeds, eventually yielded self-sustaining populations. In each case, a severe bottleneck was followed by a rapid increase in survival, which exceeded 65% after only five generations and surpassed 85% in <20 generations. Subsequent large-scale experiments indicated that survival in lentil is initially <2% and that most larvae die before they have completely entered a seed. The only potential trade-off associated with rapid adaptation to lentil was a modest increase in the time required to develop in the ancestral host, mung bean. Reciprocal crosses between a lentil-adapted line (F10) and a mung-bean line produced offspring with intermediate survival, very long development times, and small size. Although the Asian population has been kept under uniform laboratory conditions for more than 200 generations, it appears to maintain rare alleles that permit the colonization of an extremely poor host. Such standing genetic variation can account for the sporadic appearance of unusual 'biotypes' among herbivorous insects. 相似文献
96.
By differential hybridization screening, we previously selected a class of cDNA clones from a gt10 cDNA library that was constructed from the total poly(A)+ RNA of mature cowpea cotyledons (Plant Cell Physiol 31: 39–44, 1990). pSAS10, a clone of this class, hybridized with a cDNA probe complementary to poly(A)+ RNA from cotyledons collected 1 day after the onset of imbibition (DAI), but not with the cDNA probe from cotyledons at development stage II (13 to 15 days after flowering, DAF). pSAS10 mRNA was detectable only in cotyledons at development stage III (17 to 19 DAF) or later, and its level began to decline when seeds germinated. We have suggested that pSAS10 mRNA is likely to belong to the class of stored mRNA or the mRNA that is formed at the late stage of seed maturation, is conserved in quiescent seeds and becomes functional at the early stage of germination. We determined the nucleotide sequence of pSAS10 cDNA consisting of 459 bp and an approximately 36 bp poly(A) tract, and deduced the amino acid sequence of its product, a 10-kDa cysteine-rich polypeptide. Synthesis of pSAS10 mRNA was induced just before germination began, not only in mature seeds but also in immature seeds even at stages I (9 to 11 DAF) and II (13 to 15 DAF) if they were placed under conditions suitable for germination. 相似文献
97.
Conditions for plant regeneration from excised cotyledons of Vigna radiata were studied. Complete plant developed from the uncallused proximal ends of cotyledons on Murashige & Skoog's (MS), Gamborg's (B5) and C (MS salts + B5 vitamins) basal media. The basal medium C was found to be best for plant regeneration. Regeneration frequency, however, varied with genotype, size, orientation and age of explant and the different plant growth regulators combination in the medium. Addition of cytokinins induced callusing at the proximal ends of cotyledons followed by multiple shoot formation. Out of 6-benzyl aminopurine (BAP), kinetin (KIN), N (–2 isopentyl) adenine (2iP) and adenine sulphate (AS), only BAP and KIN were found to be more effective in enhancing the frequency of shoot regeneration. BAP at 1×10-1M induced maximum (60%) shoot regeneration whereas maximum number of shoots (8 to 9 shoots) per explant was observed with 5×10-6M BAP. Cotyledons excised from two-day old seedlings were most regenerative. The regenerative response of cotyledons decreased when sliced into two equal parts either longitudinally or transversely. Callusing and organogenic differentiation occured only if the petiolar end of cotyledons was in contact with medium. None of the tested treatments were effective in inducing shoot bud differentiation from subcultured callus. Well developed shoots rooted when incubated on half strength MS, MS and MS basal medium supplemented with IAA (5×10-6M). The rooted plants were transferred to pots and later established in the field with 60% success.Abbreviations AS
adenine sulphate
- BAP
6-benzylaminopurine
- B5
medium after Gamborg et al. [6],
- C
Medium with MS salts + B5 vitamins
- 2iP
N (–2 isopentyl) adenine
- IAA
indole-3-acetic acid
- KIN
Kinetin
- MS
medium after Murashige & Skoog [21]
- NAA
1-napthaleneacetic acid 相似文献
98.
Changes in catalase activity and hydrogen peroxide concentration in plants in response to low temperature 总被引:6,自引:0,他引:6
Taxicity of oxygen species such as free radicals and H2 O2 has been invoked to explain a number of degradative processes in plants, most involving photo-oxidation. Since catalase is a major protectant against accumulation and toxicity of H2 O2 , we examined alterations in catalase activity in several plant species ( Pisum sativum L. cv. Greenfeast, Vigna radiata (L.) R. Wilcz, Cucumis sativus L. cv. Heinz Pickling, and Passiflora spp.) during chilling, and compared this change to change in H2 O2 content. Catalase activity was reduced in a range of chilling sensitive and tolerant species by exposure to low temperature. This reduction in catalase activity correlated better with the onset of visible symptoms than with the treatment itself. Visible injury in turn was dependent on light and temperature differences. Hydrogen peroxide concentrations invariably decreased with low temperatures.
Reduction in catalase activity therefore does not necessarily imply accumulation of H2 O2 to damaging levels. The absence of a clear inverse relationship between catalase activity and H2 O2 concentration suggests the continued activity of other reactions that remove H2 O2 and these may be important in the tolerance of plants to oxidative attack. Loss of catalase activity may result from the inability of damaged peroxisomal membranes to transport catalase precursors into the peroxisome. 相似文献
Reduction in catalase activity therefore does not necessarily imply accumulation of H
99.
S. Dwivedi D. P. Singh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,70(4):337-337
Summary The inheritance of the dwarf plant type was studied in blackgram (V. mungo (L.) Hepper). Type 9 has erect plant type with normal internode length. The mutant line, EMSD has reduced internode length. The F1, F2 and F3 generations of a cross between Type 9 and EMSD and its reciprocal were studied. The extreme dwarf plant type appeared to be governed by a single recessive gene, dw
1
dw
1 with no cytoplasmic effect.Part of Ph.D. Thesis submitted by the first author 相似文献
100.
Bao‐Lam Huynh Bevan Emma Huang María Muñoz‐Amatriaín Stefano Lonardi Jansen R. P. Santos Arsenio Ndeve Benoit J. Batieno Ousmane Boukar Ndiaga Cisse Christian Fatokun Francis Kusi Richard Y. Agyare Yi‐Ning Guo Ira Herniter Sassoum Lo Steve I. Wanamaker Shizhong Xu Timothy J. Close Philip A. Roberts 《The Plant journal : for cell and molecular biology》2018,93(6):1129-1142
Multi‐parent advanced generation inter‐cross (MAGIC) populations are an emerging type of resource for dissecting the genetic structure of traits and improving breeding populations. We developed a MAGIC population for cowpea (Vigna unguiculata L. Walp.) from eight founder parents. These founders were genetically diverse and carried many abiotic and biotic stress resistance, seed quality and agronomic traits relevant to cowpea improvement in the United States and sub‐Saharan Africa, where cowpea is vitally important in the human diet and local economies. The eight parents were inter‐crossed using structured matings to ensure that the population would have balanced representation from each parent, followed by single‐seed descent, resulting in 305 F8 recombinant inbred lines each carrying a mosaic of genome blocks contributed by all founders. This was confirmed by single nucleotide polymorphism genotyping with the Illumina Cowpea Consortium Array. These lines were on average 99.74% homozygous but also diverse in agronomic traits across environments. Quantitative trait loci (QTLs) were identified for several parental traits. Loci with major effects on photoperiod sensitivity and seed size were also verified by biparental genetic mapping. The recombination events were concentrated in telomeric regions. Due to its broad genetic base, this cowpea MAGIC population promises breakthroughs in genetic gain, QTL and gene discovery, enhancement of breeding populations and, for some lines, direct releases as new varieties. 相似文献