INCREASE IN SEED PRODUCTION FROM NITROGEN FERTILIZATION OF NATIVE BEARDLESS WHEATGRASS

1962 ◽  
Vol 42 (2) ◽  
pp. 359-364
Author(s):  
J. E. Miltimore ◽  
J. L. Mason ◽  
C. B. W. Rogers

Nitrogen fertilization greatly increased pure seed yield of native beardless wheatgrass, Agropyron inerme, where the mean annual precipitation was 11 inches in the South Okanagan area of British Columbia. In one experiment in 1959, ammonium nitrate broadcast at 450 pounds of actual nitrogen per acre increased seed yield from 3.5 pounds per acre for the unfertilized plots to 17.5 pounds, a maximum increase of 400 per cent. One hundred and fifty pounds of actual nitrogen per acre increased seed yield 330 per cent and the 50-pound rate increased the yield of seed 140 per cent. At two other locations in 1961, unfertilized plots yielded 18.8 pounds of seed per acre; 150 pounds of actual nitrogen per acre increased seed yield to 59.2 pounds and the 50-pound treatment produced 46.5 pounds of seed per acre. Yield increases resulted from increases in spike production because weight of seed per spike was not increased by fertilization. Germination was not affected and per cent pure seed was slightly increased by the nitrogen treatments. This increase in seed production is considered favorable for the restoration of preferred species on depleted native range.

1989 ◽  
Vol 69 (3) ◽  
pp. 939-943 ◽  
Author(s):  
D. J. THOMPSON ◽  
K. W. CLARK

Three field experiments were performed to determine the effects of fall nitrogen fertilization and post-harvest mechanical stubble removal (to 2.5 cm) on seed yield in Kentucky bluegrass (Poa pratensis L. ’Nugget’). In all experiments, N fertilization and stubble removal increased seed yield. Increases were greater in a 3-yr-old than in a 5-yr-old stand. Nitrogen fertilization increased panicle density, panicle weight, shoot height and straw yield. Stubble removal increased panicle density, reduced panicle weight, shoot height, and straw yield and increased harvest index.Key words: Nitrogen, stubble removal, seed, Kentucky bluegrass


1991 ◽  
Vol 42 (1) ◽  
pp. 151 ◽  
Author(s):  
SG Shah ◽  
CJ Pearson ◽  
AC Kirby

Components of seed yield were measured in an erect, early-flowering biotype and a prostrate, late-flowering biotype of Lolium perenne cv. Kangaroo Valley at temperatures from 15/10 to 24/19�C (12/12 h day/night). We aimed to determine if each biotype had distinctive components of seed yield, and if these varied according to temperature. The two biotypes had distinctive paths to seed yield. Seed yield per plant in an erect biotype depended more on seed weight per spike and less on spike number than in a prostrate biotype. The distinctive paths to seed yield, and relative stability in paths across temperatures, indicated that it was possible to select genotypes from within the Kangaroo Valley cultivar which had particular correlations among components of yield. Floral development was accelerated, but seed yield per plant and most of its components were reduced, at high temperature; only the mean daily rate of dry weight accumulation by individual seeds was the same at all temperatures. At any temperature, seed weight per spike declined almost linearly with lateness of spike emergence within a plant: spikes which emerged within 21 days of the earliest spike contributed 80% of the seed yield per plant. We conclude that biotypes can be selected within the Kangaroo Valley cultivar to have distinctive components of seed yield and, based on the two biotypes we studied, commercial seed production should be based at a location having relatively low temperatures.


2005 ◽  
Vol 53 (3) ◽  
pp. 353-356
Author(s):  
◽  

Studies were made on the fodder and seed production of ryegrass (Lolium perenne L.) using twelve treatment combinations with four levels of nitrogen (30, 60, 90 and 120 kg/ha/cut) and three levels of phosphorus (0, 50 and 100 kg P2O5/ha), laid out in a randomized block design with four replications. The mean of two years indicated that nitrogen at 120 kg/ha/cut increased the green fodder (834 q/ha) and dry matter yield (129 q/ha) significantly over the lower doses. After leaving the same crop for seed production during mid-March, nitrogen at the rate of 60 kg/ha gave the highest seed yield (7.61 q/ha). Beyond this dose the seed yield decreased drastically due to lodging. Phosphorus at the rate of 50 kg P2O5/ha gave 5% higher dry matter (99.6 q/ha) and 7.4% higher seed yield (7.26 q/ha) over the control.


1978 ◽  
Vol 54 (2) ◽  
pp. 88-91 ◽  
Author(s):  
R. F. Calvert

The objective of this study was to investigate variation in cone size and seed production in Manitoba white spruce so that general guides to seed collection could be developed. Relationships were established using regression techniques which permitted the development of a three category cone crop classification system based on the probable yield of sound seed from cones. It is tentatively suggested to use this system, that the mean number of filled seed on one half of longitudinal cone sections be determined from a minimum of five to ten cones taken from all aspects of the top two to three m of each of six to ten dominant or co-dominant trees. A crop quality rating is then determined by relating this to a graph which indicates a Good, Fair or Poor seed yield.


Author(s):  
Muhammad Zeeshan Mehmood ◽  
Ghulam Qadir ◽  
Obaid Afzal ◽  
Atta Mohi Ud Din ◽  
Muhammad Ali Raza ◽  
...  

AbstractSeveral biotic and abiotic stresses significantly decrease the biomass accumulation and seed yield of sesame crops under rainfed areas. However, plant growth regulators (such as Paclobutrazol) can improve the total dry matter and seed production of the sesame crop. The effects of the paclobutrazol application on dry matter accumulation and seed yield had not been studied before in sesame under rainfed conditions. Therefore, a two-year field study during 2018 and 2019 was conducted with key objectives to assess the impacts of paclobutrazol on leaf greenness, leaf area, total dry matter production and partitioning, seed shattering, and seed yield of sesame. Two sesame cultivars (TS-5 and TS-3) were treated with four paclobutrazol concentrations (P0 = Control, P1 = 100 mg L−1, P2 = 200 mg L−1, P3 = 300 mg L−1). The experiment was executed in RCBD-factorial design with three replications. Compared with P0, treatment P3 improved the leaf greenness of sesame by 17%, 38%, and 60% at 45, 85, and 125 days after sowing, respectively. However, P3 treatment decreased the leaf area of sesame by 14% and 20% at 45 and 85 days after sowing than P0, respectively. Compared with P0, treatment P3 increased the leaf area by 46% at 125 days after sowing. On average, treatment P3 also improved the total biomass production by 21% and partitioning in roots, stems, leaves, capsules, and seeds by 23%, 19%, 23%, 22%, and 40%, respectively, in the whole growing seasons as compared to P0. Moreover, under P3 treatment, sesame attained the highest seed yield and lowest seed shattering by 27% and 30%, respectively, compared to P0. This study indicated that by applying the paclobutrazol concentration at the rate of 300 mg L−1 in sesame, the leaf greenness, leaf areas, biomass accumulation, partitioning, seed yield, and shatter resistance could be improved. Thus, the optimum paclobutrazol level could enhance the dry matter accumulation and seed production capacity of sesame by decreasing shattering losses under rainfed conditions.


1987 ◽  
Vol 11 (1) ◽  
pp. 6-9 ◽  
Author(s):  
Robert C. Hare

Abstract A single foliar spray with either antiethylene compounds or cytokinins shortly after anthesis reduced conelet abortion by half and doubled seed production. Spraying with boric acid plus Cytex® , a relatively economical form of cytokinin derived from seaweed, was equally effective,and addition of certain antiethylene compounds further improved seed yield. South. J. Appl. For. 11(1):6-9.


Weed Science ◽  
1990 ◽  
Vol 38 (2) ◽  
pp. 113-118 ◽  
Author(s):  
S. Kent Harrison

Multiple regression and response surface plots were used to analyze the effects of common lambsquarters population density and interference duration on weed growth and soybean seed yield. Under favorable growing conditions in 1986, weed biomass production at all population densities and interference durations was four to five times that produced in 1987, under less favorable conditions. However, there was no significant treatment by year interaction for soybean seed yield reduction by common lambsquarters, and production of each kg/ha weed biomass resulted in an average soybean yield reduction of 0.26 kg/ha. Utilizing 5% yield loss as an arbitrary threshold level, the regression equation predicted a common lambsquarters density threshold of 2 plants/m of row for 5 weeks of interference after crop emergence and 1 plant/m of row for 7 weeks. Seed production by individual common lambsquarters plants was highly correlated (r=0.92) with weed dry weight, and seed production ranged from 30 000 to 176 000 seeds/plant.


1969 ◽  
Vol 49 (2) ◽  
pp. 149-154 ◽  
Author(s):  
J. L. Mason

Nitrogen treatments from 0.15 to 0.90 kg of nitrogen and cultivation treatments from zero to three shallow rotovations were applied in a split-plot design to 30-year-old McIntosh apple trees growing in irrigated grass sod.Fruit quality was very largely unaffected by the treatments. Pressure test after harvest was reduced from 6.61 to 6.44 kg (P = 0.10) as nitrogen increased. Number of rots increased from 2.7 to 3.9 per 60-fruit sample with increasing nitrogen. Titratable acidity and soluble solids after harvest and pressure test, titratable acidity, soluble solids, stem-cavity browning and core flush in tests after storage were all unchanged. In addition, none of these tests were affected by cultivation except pressure test, which decreased with more cultivation (P = 0.10).Yield was not changed by either the nitrogen or the cultivation treatments, and terminal length increased only slightly with more cultivation. However, nitrogen concentration in the leaf was increased from 1.90 to 1.98% by the nitrogen treatments and from 1.83 to 1.98% by increasing cultivation. Extra Fancy grade was reduced and C grade increased by increasing nitrogen (P = 0.10), but cultivation had no effect.The conclusion is drawn that grass sod can very largely eliminate the effect of widely different nitrogen fertilization levels on McIntosh apple, and that moderate cultivation changes this effect only slightly. In many mature orchards of high initial fertility, nitrogen fertilizer may be required in only small amounts or even not at all for optimum fruit color.


1990 ◽  
Vol 70 (4) ◽  
pp. 1071-1080 ◽  
Author(s):  
LUCIUS BELZILE

For five years, the effect of cultivars and vegetative stage of cutting were measured on red clover (Trifolium pratense L.) seed production. The first group of cultivars included Hungaropoli, Ottawa and Lakeland harvested in 1981 and 1982. The second group included Arlington, Florex and Prosper I harvested in 1984, 1985 and 1987. The total annual seed yield differed within cultivars and the highest seed yield was obtained with Hungaropoly and Florex. In the first cultivar group, the tetraploid Hungaropoly obtained a kernel weight higher than the diploids Lakeland and Ottawa. In the second group of cultivars, all diploids, Arlington yielded the highest kernel weight. The percentage of seed germination of Hungaropoly was higher than Lakeland and Ottawa while for Florex it was slightly higher than Arlington and Prosper I. A prior vegetative cutting is essential for good seed yield. In the absence of vegetative cutting seed weight seemed improved. The stage of development at which vegetative cutting is done has little influence on percentage seed germination. These results have shown that despite the strong effect of climatic conditions on seed production, the choice of the optimum stage for vegetative cutting and a well adapted cultivar are important aspects in successful seed production.Key words: Red clover, seed production, cultivar, stage of cutting


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