Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 20 (1989), S. 75-82 
    ISSN: 1573-0867
    Keywords: Triticum vulgare L. ; banding and broadcasting P ; total dry matter ; total P uptake ; anthesis grain filling periods
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Cereals grown on calcareous soils in a dry Mediterranean climate have generally responded to P fertilizer. Broadcasting is the common practice used by most farmers. The effects of rate and method of phosphate placement on dry matter production (TDM), grain yield and P uptake by durum wheat (Triticum vulgare L.) were investigated. Factorial experiments with four levels of P (0, 17.5, 35, and 52.5 kg P ha−1) and 2 methods of application (banding by drilling with the seeds, and broadcasting before surface tillage and sowing) were conducted for three consecutive seasons at three experimental sites: Breda (Typic Calciorthid, 281 mm); Tel Hadya (Chromoxeretic Rhodoxeralf, 328 mm) and Jindiress (Palexerollic Chromoxerert, 471 mm). Three levels of P were used in the third season only. Treatments were replicated in three blocks. The average values of NaHCO3-extractable P in the plow layer were 2.8, 3.7 and 2.1 mg P kg−1 at Breda, Tel Hadya, and Jindiress, respectively. Above-ground total dry matter (TDM) was determined at tillering and anthesis. Grain and straw yields were estimated separately at harvest. The P concentration in plant material was determined at both stages. At tillering, TDM and total P uptake (TPU) increased linearly with the rate of P applied. It was found that (i) 17.5 kg P ha−1 banded was as effective in increasing TDM and TPU as 52.5 kg P ha−1 broadcast, and (ii) the average relative percentage increase in TDM at tillering due to P banded as compared to P broadcast was 54%, with significantly less response to banding, by maturity and harvest. The response to P placement was found to be site related. At Breda, banding was found superior to broadcasting in all 3 seasons with a relative increase in grain yields equivalent to 34, 63 and 23% in the 3 successive seasons, when optimum amounts of P were applied. However, in two out of three seasons only banding was found superior to broadcasting at both Tel Hadya and Jindiress. As a result, banding P is recommended for durum wheat grown on the calcareous soils of the Mediterranean regions because it stimulates growth and P uptake early in the season and increases the crop potential for good grain and straw yields especially in dry areas. Given equal rates of P application, banding was found superior to broadcasting in most cases.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1615-6102
    Keywords: Cell cycle ; Protoplast division ; Chromatin structure ; Flow-cytometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Using different sources of protoplasts and two complementary techniques, flow cytometry and image analysis, to study the cell-cycle phases, we sought to define the particular protoplast state associated with the disposition to divide. Both inPetunia and inNicotiana plumbaginifolia, tissues with a higher G2 frequency (from different aged plants) yielded protoplasts capable of increased cell division. InSorghum, the age of the plant does not modify the proportion of G2 nuclei in leaf protoplasts, and we used root protoplasts to increase G2 frequencies. InHelianthus annuus, leaf protoplasts did not divide; however, hypocotyl protoplast preparations with relatively high 4C DNA frequencies do divide. Moreover, image analysis of chromatin structure indicated that leaf nuclei were in the G0 phase, unlike those from hypocotyls which were in G1. A high frequency of protoplasts with G2 nuclei appears to be correlated with the ability of a given preparation to undergo division; conversely, the differentiated G0 state is not conducive to division.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...