Application of cytokinins to flowers to increase pod set in Lupinus angustifolius L

1993 ◽  
Vol 44 (8) ◽  
pp. 1799 ◽  
Author(s):  
CA Atkins ◽  
A Pigeaire

Exogenous application of a 2 mol m-3 buffered solution of N6 benzylaminopurine (BAP) to flowers on the main stem inflorescence of Lupinus angustifolius L, cv. Danja profoundly altered reproductive development by reducing post-anthesis abscission of flowers and small pods. The same effect of BAP was recorded for a mutant (abs-) of cv. Danja, in which organ abscission was completely absent, indicating that localized application of cytokinin enhanced reproductive development rather than reduced pedicel abscission per se in the parent line. Application to pedicel and sepals at the open flower stage completely eliminated flower abortion on the main inflorescence, compared with less than 50% pod initiation on untreated inflorescences, more than doubled final pod yield on the main inflorescence and increased the number of mature pods on the whole plant by 33%. A single dose of BAP, to an inflorescence which bore flowers ranging in their stage of development from post-anthesis to immature flower buds, significantly increased the number of pods initiated and at final harvest, measured on a per plant basis. A number of synthetic and naturally occurring cytokinins, including zeatin riboside and dihydrozeatin riboside, were also effective. BAP application induced a longer period of flowering and resulted in a considerably thickened raceme. This was most marked at the distal end which showed enhanced cambial development and secondary vascularization compared with untreated controls. The positive effects of BAP application on pod initiation were not restricted to cv. Danja but were found also for cv. Warrah and cv. Gungurru, both of which have enhanced pod set compared with Danja. Enhanced pod initiation on the main inflorescence generally reduced the number of pods developing on branch inflorescences. Additional application of BAP to flowers on branches, even at the most opportune time and at the most effective site, did not enhance pod initiation and, in some cases, significantly reduced pod set on these branches. The data indicate that it would be very difficult to exploit the positive effect of exogenous cytokinin application on pod set in field crops of lupin. However, selection or genetic engineering of plants with higher levels of endogenous cytokinins in flowers or flower parts at anthesis may provide a means by which to assess the importance of this factor in determining yield stability.

2018 ◽  
Vol 19 (10) ◽  
pp. 3278 ◽  
Author(s):  
Zhineng Li ◽  
Yingjie Jiang ◽  
Daofeng Liu ◽  
Jing Ma ◽  
Jing Li ◽  
...  

Wintersweet (Chimonanthus praecox) is a well-known traditional fragrant plant and a winter-flowering deciduous shrub that originated in China. The five different developmental stages of wintersweet, namely, flower-bud period (FB), displayed petal stage (DP), open flower stage (OF), later blooming period (LB), and wilting period (WP) were studied using a scanning electron microscope (SEM) to determine the distribution characteristics of aroma-emitting nectaries. Results showed that the floral scent was probably emitted from nectaries distributed on the adaxial side of the innermost and middle petals, but almost none on the abaxial side. The nectaries in different developmental periods on the petals differ in numbers, sizes, and characteristics. Although the distribution of nectaries on different rounds of petals showed a diverse pattern at the same developmental periods, that of the nectaries on the same round of petals showed some of regularity. The nectary is concentrated on the adaxial side of the petals, especially in the region near the axis of the lower part of the petals. Based on transcriptional sequence and phylogenetic analysis, we report one nectary development related gene CpCRC (CRABS CLAW), and the other four YABBY family genes, CpFIL (FILAMENTOUS FLOWER), CpYABBY2, CpYABBY5-1, and CpYABBY5-2 in C. praecox (accession no. MH718960-MH718964). Quantitative RT-PCR (qRT-PCR) results showed that the expression characteristics of these YABBY family genes were similar to those of 11 floral scent genes, namely, CpSAMT, CpDMAPP, CpIPP, CpGPPS1, CpGPPS2, CpGPP, CpLIS, CpMYR1, CpFPPS, CpTER3, and CpTER5. The expression levels of these genes were generally higher in the lower part of the petals than in the upper halves in different rounds of petals, the highest being in the innermost petals, but the lowest in the outer petals. Relative expression level of CpFIL, CpCRC, CpYABBY5-1, and CpLIS in the innermost and middle petals in OF stages is significant higher than that of in outer petals, respectively. SEM and qRT-PCR results in C. praecox showed that floral scent emission is related to the distribution of nectaries.


2001 ◽  
Vol 44 (10) ◽  
pp. 121-128 ◽  
Author(s):  
J.A. Müller

Pre-treatment processes have been developed in order to improve subsequent sludge treatment and disposal. Disintegration of sludge solids in the aqueous phase changes the sludge structure and solubilizes organic matter. This paper provides an overview of the applications of wet disintegration in wastewater and sludge treatment. Applied disintegration techniques such as mechanical, thermal, chemical and biological methods are briefly described. The methods are compared regarding energy consumption, operational reliability and stage of development for application on wastewater treatment plants. Mechanical and thermal methods appear to be most suitable at this stage. The effects of pre-treatment on subsequent sludge treatment processes and the wastewater treatment are described. The performance of various methods is assessed. For the improvement of stabilization, mechanical and ozone treatment as well as thermal treatment perform best. Dewatering can be enhanced by thermal and freeze/thaw treatment. All methods show positive effects in the reduction of the number of pathogens. Pre-treatment leads to secondary effects like the generation of recalcitrant compounds and odor, which is mainly a problem of thermal and ozone treatment. The evaluation of capital and operational costs is difficult, because of the lack of full-scale experience. Especially thermal, freeze/thaw and biological treatments can be realized at low costs if the conditions are appropriate. Nevertheless, the economic efficiency has to be investigated critically for each individual application.


2001 ◽  
Vol 47 (9) ◽  
pp. 829-841 ◽  
Author(s):  
Lisa A May ◽  
Brenda Smiley ◽  
Michael G Schmidt

Significant portions of grain produced for livestock consumption are converted into ensiled forage. Silage producers have long recognized the positive effects of using an inoculant to insure the proper transformation of forage into a palatable and digestible feedstuff. When silage is fed from a storage structure, exposure to air stimulates the growth of epiphytic aerobes that may result in the loss of up to 50% of the dry matter. Moreover, fungi have been found to be associated with ensiled forage, but their growth is normally suppressed by the anaerobic conditions. However, the introduction of oxygen results in a fungal bloom, and the fungi and the associated metabolites may result in lost productivity in the livestock consuming the contaminated forage. In this study, we report on the diversity of the fungal community associated with whole plant corn silage during the ensiling process, and the effect of two different bacterial inoculants as compared with the uninoculated natural epiphytic fermentation on the distribution of the fungi associated with the silage. The fungal community from duplicate mini-silo packages of the same treatment was analyzed by denaturing gradient gel electrophoresis and direct sequencing of the resulting operational taxonomic units. This method proved useful in analyzing the complex microbial communities associated with the forage in that it was possible to determine that one inoculant dramatically influenced the fungal community associated with whole plant corn silage.Key words: fungi, silage, DGGE, OTU.


2018 ◽  
Vol 70 (5) ◽  
pp. 441-452 ◽  
Author(s):  
Rilana Prenger ◽  
Cindy L. Poortman ◽  
Adam Handelzalts

Teacher professional learning is considered crucial for improving the quality of education. Teacher collaboration in professional learning communities can contribute to the effectiveness of professional development efforts. In the past decade, there has been a shift from within-school to between-school professional learning communities. However, results regarding their effectiveness have been inconsistent. In this study, we examine the effects of 23 networked professional learning communities in the Dutch context, using a mixed-methods approach. Results showed moderately positive effects on teachers’ perceived satisfaction; the knowledge, skills, and attitude developed; and their application to practice. Considering the early stage of development of these professional learning communities, teachers’ participation in networked professional learning communities seems promising for enhancing their professional learning.


1976 ◽  
Vol 16 (80) ◽  
pp. 387 ◽  
Author(s):  
P Farrington

Reproductive development, and the distribution of dry matter and nitrogen were followed in field plantings of Lupinus angustifolius cv. Uniharvest and L. cosentinii selection CB12 from the start of flowering until maturity. L. cosentinii (CBI 2) commenced flowering one week earlier, but developed one less order of inflorescences and fewer flowers than L. angustfiolius (Uniharvest) ; yet it set more pods and produced more seed. In both species seeds did not commence to fill until the leaves began to fall shortly after flowering ended. Seeds in pods on all orders of inflorescence filled concurrently. The increase in seed weight coincided with a rapid fall in the nitrogen content of other fractions of the tops.


1987 ◽  
Vol 10 (2) ◽  
pp. 83-113 ◽  
Author(s):  
Manfred Pienemann

Abstract In this article it is claimed that there is a set of universal speech processing constraints which applies to all types of second language acquisition. These constraints define the range of possible hypotheses about the structure of the L2 which a learner can create at a given stage of development and cannot be overridden by formal instruction or by other alterations in the linguistic input. These claims, however, do not imply that all types of language acquisition are identical or that teaching has no influence whatsoever on the way a second language develops in a formal context. It has been shown elsewhere (cf. Pienemann, 1984, 1985, 1987a) that under certain conditions teaching can influence formal L2 development. These demonstrable positive effects of teaching, however, remain inside the variational margin left open by the processing constraints. The present paper reports on the interlanguage development of one learner of German as a second language, selected from a broader longitudinal study of one year’s duration. It was found that the learner’s word order development was identical to the natural development of German as a second language despite the progression intended in the teaching. A similar result was obtained in the development of verbal morphology. It is also shown that agreement marking is acquired at the same time as specific word order rules.


Plants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 666
Author(s):  
Hafiz Muhammad Kamran ◽  
Syed Bilal Hussain ◽  
Shang Junzhong ◽  
Lin Xiang ◽  
Long-Qing Chen

Geranyl diphosphate synthase (GPPS) is a plastid localized enzyme that catalyzes the biosynthesis of Geranyl diphosphate (GPP), which is a universal precursor of monoterpenes. Wintersweet (Chimonanthus praecox L.), a famous deciduous flowering shrub with a strong floral scent character, could have GPPS-like homologs that are involved in monoterpenes biosynthesis, but it remains unclear. In the present study, five full-length GPPS and geranylgeranyl diphosphate synthases (GGPPS) genes were identified in the wintersweet transcriptome database. The isolated cDNAs showed high protein sequence similarity with the other plants GPPS and GGPPS. The phylogenetic analysis further classified these cDNAs into four distinct clades, representing heterodimeric GPPS small subunits (SSU1 and SSU2), homodimeric GPPS, and GGPPS. Analysis of temporal expression revealed that all genes have the highest transcript level at the full-open flower stage. From tissue-specific expression analysis, CpGPPS.SSU1 and CpGGPPS1 were predominantly expressed in petal and flower, whereas CpGPPS.SSU2, GPPS, and GGPPS2 showed a constitutive expression. Additionally, the subcellular localization assay identified the chloroplast localization of SSUs and GGPPSs proteins, and the yeast two-hybrid assay showed that both CpGPPS.SSU1 and CpGPPS.SSU2 can interact with the GGPPS proteins. Taken together, these preliminary results suggest that the heterodimeric GPPS can regulate floral scent biosynthesis in wintersweet flower.


Author(s):  
Jeff C Clements ◽  
Claire E Carver ◽  
Martin A Mallet ◽  
Luc A Comeau ◽  
André L Mallet

Abstract In North America, studies regarding effects of CO2-induced low pH in bivalve aquaculture are largely restricted to the US Pacific coast. Studies on species from the northwest Atlantic are lacking. Furthermore, information on the roles of intergenerational exposure and biological sex in bivalve responses to low pH, particularly in an aquaculture-specific context, is scant. We tested if short-term (1 month) exposure to CO2-induced reductions in pHNBS affected the reproductive development of male and female eastern oysters (Crassostrea virginica) during hatchery-specific reproductive conditioning and whether maternal and/or paternal exposure influenced larval responses. Reduced pH (7.5–7.7) increased the rate of reproductive development in both males and females. There was no indication of intergenerational effects; adult pH conditions did not affect early larval development. In contrast, low pH conditions experienced by gametes during spawning, fertilization, and embryo incubation (48 h) resulted in higher larval survival (+6–8% from control), reduced shell height (−2 to 3 µm), and increased deformities (abnormal shell shape; +3–5%). We suggest that local adaptation to acidic land runoff may account for the positive effects of low pH observed in this study. Bioeconomic assessments are now needed to understand the implications of reduced pH on aquaculture operations in these regions of Atlantic Canada.


2015 ◽  
Vol 84 (3) ◽  
pp. 257-268 ◽  
Author(s):  
Jana Krejcarová ◽  
Eva Straková ◽  
Pavel Suchý ◽  
Ivan Herzig ◽  
Kateřina Karásková

Sea buckthorn (Hippophae rhamnoides L.) is in the focus of interest mainly for its positive effects on health of both human and animal organisms. The whole plant of sea buckthorn and especially its berries are a source of a large number of different bioactive compounds. The greatest attention has been drawn to its high content of vitamins, minerals, natural antioxidants, n-3 and n-6 fatty acids, and proteins. Sea buckthorn is valued for its antioxidant, cardioprotective, antiatherogenic, antidiabetic, hepatoprotective, anti-carcinogenic, immunomodulatory, antiviral, antibacterial, anti-inflammatory and vasorelaxant effects. Due to these and other positive effects, the plant is included in both human and animal nutrition, in the latter case to increase the biological value of animal products. This review summarises the botanical characteristics of sea buckthorn, lists the bio-active substances contained in individual parts of the plant, their effects in the prevention of a number of different diseases and their possible utilisation in human and animal nutrition.


Author(s):  
M.-Miao Xie, Q.-Sheng Wu

Arbuscular mycorrhizal fungi (AMF) represent positive effects on growth performance, nutrient absorption and stressed tolerance of host plants, whereas it is not clear whether AMF can affect flowering traits of ornamental plants. In this work, Diversispora spurca, D. versiformis, and Funneliformis mosseae were applied to rhizosphere of potted hyacinth (Hyacinths orientalis L. Anna Marie) plants. After four months of mycorrhizal inoculation, root could be colonized by exogenous AMF species, varied from 38% to 49%, whilst F. mosseae had the best mycorrhizal status. Out of these AMF species used, only F. mosseae-inoculated plants recorded greater raceme length and biomass production of single flowerlet, raceme, and flower stem. F. mosseae also induced the flowering earlier in 2 days and prolonged flowering time for 3 days. D. versiformis postponed 2 days for flowering. Mycorrhizal plants recorded considerably higher acetic acid (IAA) and zeatin riboside (ZR) levels in flowers, irrespective of AMF species. F. mosseae-inoculated plants had significantly higher methyl jasmonate (MeJA) concentrations in flowers than other AMF- or non-AMF-treated plants. These results thereby conclude that F. mosseae can be used to regulate flowering of H. orientalis L. Anna Marie, including flowering earlier and prolonging flowering time, which is closely associated with IAA, ZR and MeJA levels in flowers.


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