Responses of Leymus arenarius to Nutrients: Improvement of Seed Production and Seedling Establishment for Land Reclamation

1997 ◽  
Vol 34 (5) ◽  
pp. 1165 ◽  
Author(s):  
S. Greipsson ◽  
A. J. Davy
Author(s):  
J.F.L. Charlton

Seeds mixtures for New Zealand pastures developed from British practices with sowing of multi-species seeds mixtures during early years of settlement. Breeding and seed production of ryegrasses and clovers in the 1930s led to use of simple mixtures, still the most commonly used. Since the mid 197Os, new species have been released, and are now becoming more popular. Advantages and some potential problems of species mixtures are outlined, and simple concepts of compiling seeds mixtures are explained, with particular reference to seeding rate and sowing time. Keywords species, seeds mixtures, pasture renewal, sowing rates, seedling establishment, competition


1993 ◽  
Vol 17 (1) ◽  
pp. 10-15 ◽  
Author(s):  
William D. Boyer

Abstract Well-stocked mature longleaf pine (Pinus palustris Mill.) stands were cut to five residual basal areas in 1957, namely 9, 18, 27, 36, and 45 ft² per ac, to observe the effect of stand density on seed production and seedling establishment. Seedlings, mainly from the 1955 or 1961seed crops, were established in treated stands. All pines on net 0.9 ac plots were remeasured in 1991 to determine the effect of residual pine density on development of the regeneration. Even the lightest residual overstory converted the structure of 29- to 35- yr-old ingrowth into the reverse-Jdiameter class distribution characteristic of uneven-aged stands. Four or six residual trees, now comprising 7 to 10 ft² basal area (ba)/ac, reduced ingrowth basal area to about half that of same-aged stands released from overstory competition. Merchantable volume of ingrowth under theselow residual densities averaged 40% of that in released stands. Mean annual per ac volume increment of ingrowth averaged 21 to 22 ft³ under the 9 ft² density but did not exceed 7 ft³ under any residual density above this. The potential impact of significant growth reductionsshould be taken into account when considering uneven-aged management methods for longleaf pine. South. J. Appl. For. 17(1):10-15.


Author(s):  
Sunil Kumar ◽  
Satbir Singh Jakhar ◽  
Anil Kumar Malik ◽  
Sangeet Kumar

The present study was carried out in the field and laboratory of the Department of Seed Science and Technology, CCS Haryana Agricultural University, Hisar, Haryana during 2018-2019 to know the effect of nodal position of fruits on seed quality of okra. The parameters recorded during laboratory studies were i.e. germination, seedling length, seedling dry weight, vigour indices-1 & 2 and field studies were i.e. field emergence index, seedling establishment. The results indicated that the best nodal position of fruits for quality seed production was middle nodes (6th to 10th) as compared to lower nodes (1st to 5th) and upper nodes (11th to 15th) and the control.


2019 ◽  
Vol 21 (5) ◽  
pp. 1683-1695 ◽  
Author(s):  
Carolina Musso ◽  
Mariana Aragão de Macedo ◽  
Niquele Nunes Almeida ◽  
Danillo de Melo Rodrigues ◽  
Maria Eduarda Moreira Salomon Camargo ◽  
...  

1986 ◽  
Vol 34 (4) ◽  
pp. 425 ◽  
Author(s):  
AM Gill ◽  
A Mcmahon

The fire-sensitive shrub Banksia ornata relies on seed stored in serotinous 'cones' for its regeneration. Seed release takes place largely as a result of fire but a very small percentage of fruits may open spontaneously. In a chronosequence studied in heaths of the Little Desert of north-western Victoria, we found no seedling establishment in the absence of fire except in the oldest stand, dated at 50+ years since fire. Seed quantity was low in stands 6-7 years old but rose to a peak in the 38-year-old stand. The decline of seed quantity in the 50+ year-old stand was due to dieback and death of bushes. There was no evidence for an increase in the proportion of seeds predated with age of stand. An average of about 70% of the seed was regarded as 'intact' (no sign of damage) and about 80% of these seeds germinated under ideal laboratory conditions. It was estimated that the amount of seed available for regeneration increased with stand age up to 38 years but declined by 50+ years. It was suggested that a period of 16 years without fire could be needed to achieve stand replacement of populations of this species. The age at which full replacement can be achieved will vary, however, according to fire intensity and seasonal weather conditions. Further quantitative research is needed.


Author(s):  
M.E. Wedderburn ◽  
W.L. Lowther

Observations of blocks oversown with Maku lotus in the Otago tussock grasslands have indicated that the potential yields are not being obtained as a result of low seedling establishment and limited spread of established plants. Satisfactory establishment is dependent on correct aerial oversowing techniques and suitable site preparation. Inoculation with rhizobia is essential for nodulation on most areas of the tussock grasslands and the present recommendation is to slurry-inoculate seed at up to 5times the normal manufacturers rate. The incorporation of 10% (w:v) gum arabic in the slurry improves viability of rhizobia and allows seed to be stored for 1-2 weeks before sowing. Vegetative spread of established plants depend on growth of rhizomes during the summer/autumn period. This rhizome growth is sensitive to time of defoliation of the sward. Defoliation as early as the start of January reduced the amount of rhizome present in April while early-February or early-March defoliation virtually eliminated rhizome growth. In sparse swards of Maku lotus where maximum spread of existing plants is required it is recommended that grazing be avoided over this critical period. Where adequate plant density has been obtained either through the use of correct seedling establishment techniques or earlier management for rhizome spread, it is not necessary to adhere to this recommendation and swards can be rotationally grazed over the summer/autumn period. Seed production of Maku lotus is limited, particularly at higher altitudes and on shady aspects, and the technique of natural reseeding has limited application in these tussock grasslands. Keywords: grazing management, inoculation, Maku lotus, rhizome, seed production


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