Shoot

About: Shoot is a research topic. Over the lifetime, 32188 publications have been published within this topic receiving 693348 citations.

Proteome analysis of potato under salt stress.

Abstract: Because salt stress is a major abiotic source of stress on potato crops, the molecular mechanism of the response of potato plants to salt stress was examined. On exposure to salt, the salt-sensitive cultivar Concord showed a greater reduction in shoot and root length than did the salt-tolerant cultivar Kennebec. For both cultivars, the reduction in the length of shoots was more severe than that of the roots. Salt exposure increased the content of free proline and total soluble sugars in shoots of Kennebec; these remained unchanged in Concord. Proteins extracted from shoots of both cultivars exposed to 90 mM NaCl were separated by two-dimensional polyacrylamide gel electrophoresis: 322 and 305 proteins were detected in shoots of Kennebec and Concord, respectively. Of these, 47 proteins were differentially expressed under NaCl treatment in shoot of both cultivars. Among the differentially expressed proteins, photosynthesis- and protein-synthesis-related proteins were drastically down-regulated, whereas osmotine-like proteins, TSI-1 protein, heat-shock proteins, protein inhibitors, calreticulin, and five novel proteins were markedly up-regulated. These results suggest that up-regulation of defense-associated proteins may confer relative salt tolerance to potato plants.

Patterns of tillering and grain production of winter wheat at a wide range of plant densities.

Abstract: The effect of plant density on the growth and productivity of the various ear-bearing stems of winter wheat was studied in detail to obtain information on the pattern of grain production of crops grown under field conditions. Strong compensation effects were measured: a 160-fold increase in plant density (5-800 plants/m2) finally resulted in a 3-fold increase in grain yield (282 to 850 g DM/m2). Max. grain yield was achieved at 100 plants/m2, which corresponded to 430 ears/m2 and to about 19 000 grains/m2. At higher plant densities more ears and more grains were produced, but grain yield remained constant. Tillering/plant was largely favoured by low plant densities because these allowed tiller formation to continue for a longer period and a greater proportion of tillers produced ears. However, at higher plant densities more tillers/unit area were formed and, despite a higher mortality, more ears were produced. The productivity of individual ears, from main stems as well as from tillers, decreased with increasing plant density and with later emergence of shoots. In the range from 5 to 800 plants/m2 grain yield/ear decreased from 2.40 to 1.14 g DM. At 800 plants/m2 nearly all ears originated from main stems, but with decreasing plant density tillers contributed increasingly to the number of ears. At 5 plants/m2, there were 23 ears/plant and grain yield/ear ranged from 4.20 (main stem) to 1.86 g DM (late-formed stems). Grain number/ear was reduced at higher densities and on younger stems, because there were fewer fertile spikelets and fewer grains in these spikelets. At the low density of 5 plants/m2, plants developed solitarily and grain yield/ear was determined by the number of grains/ear as well as by grain wt. Above 400 ears/m2, in this experiment reached at 100 plants/m2 and more, grain yield/ear depended solely on grain number, because the wt. of grains of the various stems were similar. The harvest index showed a max. of about 44% at a moderate plant density; at this density nearly max. grain yield was achieved. At low plant densities the harvest index decreased from 45% in main stems to about 36% in late-formed stems. However, no differences in harvest index existed between the various ear-bearing stems if the number of ears exceeded 400/m2. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Phytoremediation: the application of vermicompost to remove zinc, cadmium, copper, nickel and lead by sunflower plant

Abstract: A greenhouse experiment was conducted to determine the phytotoxic effect of heavy metals such as Cd, Cu, Ni, Pb and Zn on the growth of Sunflower (Helianthus annuus): on the seed germination, root/shoot growth and uptake of metals in soil-vermicompost media. The selected metals were dosed at various concentrations ranging from 0, 5, 10, 20, 40 and 50 ppm separately in soil vermicompost media (3:1) in pot experiment. The seed germination, root and shoot growth were found significantly affected by these metals at higher concentration of 40 and 50 ppm. However, the lower concentration of heavy metals ranging from 5 to 20 ppm doses were observed to be stimulating the root and shoot length and increase biomass of the sunflower plant. Sunflower was able to germinate and grow efficiently at all Zn concentration evaluated in this study. The research study of the sunflower indicates the heavy metal uptake at the concentrations 5, 10, 20, 40 and 50 ppm. Sunflower is a very fast-growing industrial oil crop with a high biomass producing plant to be used for phytoremediation (uptake) of toxic metals (Cu, Zn, Pb, Hg, As, Cd, Ni) from soil in heavily contaminated areas. Vermicompost can be used to remediate metals contaminated sites because it binds metals and increase uptake by providing nutrients such as sodium, magnesium, iron, zinc, manganese and copper which can serve as a natural fertilizer giving high yield of biomass and microbial consortium helped the overall growth of the sunflower plant. The use of vermicompost amended soil would be effective to remediate the heavy metals from contaminated environment.

Differentiation of Tobacco Plants from Single, Isolated Cells in Microcultures

Abstract: Single cells isolated from pith callus of fresh stem of hybrid tobacco (Nicotiana glutinosa male symbol x N. tabacum female symbol) gave rise to small colonies of cells in microcultures which upon transfer to agar medium produced clones of callus tissue. These single-cell clones differentiated roots, and shoots with green leaves, on a completely defined nutrient medium. The rooted shoots developed into normal plants after transfer to soil in pots in the greenhouse. Buds and flowers were produced by these plants.

Universal florigenic signals triggered by FT homologues regulate growth and flowering cycles in perennial day-neutral tomato

Abstract: The transition from vegetative to floral meristems in higher plants is programmed by the coincidence of internal and environmental signals. Classic grafting experiments have shown that leaves, in response to changing photoperiods, emit systemic signals, dubbed 'florigen', which induce flowering at the shoot apex. The florigen paradigm was conceived in photoperiod-sensitive plants: nevertheless it implies that although activated by different stimuli in different flowering systems, the signal is common to all plants. Tomato is a day-neutral, perennial plant, with sympodial and modular organization of its shoots and thus with reiterative regular vegetative/reproductive transitions. SINGLE FLOWER TRUSS a regulator of flowering-time and shoot architecture encodes the tomato orthologue of FT, a major flowering integrator gene in Arabidopsis. SFT generates graft-transmissible signals which complement the morphogenetic defects in sft plants, substitute for light dose stimulus in tomato and for contrasting day-length requirements in Arabidopsis and MARYLAND MAMMOTH tobacco. It is discussed how systemic signals initiated by SFT interact with the SELF PRUNING gene to regulate vegetative to reproductive (V/R) transitions in the context of two flowering systems, one for primary apices and the other for sympodial shoots.