Seed production and dormancy in Rumex crispus. II. The effects of removal of various proportions of flowers at anthesis

1971 ◽  
Vol 49 (10) ◽  
pp. 1841-1848 ◽  
Author(s):  
M. A. Maun ◽  
P. B. Cavers
Keyword(s):  
Seed Production ◽  
Seed Weight ◽  
Total Yield ◽  
Lower Portion ◽  
Rumex Crispus ◽  
Individual Seed ◽  
The Mean ◽  
Seeds And Fruits

Systematic removal of 25, 50, and 75% of the flower whorls from panicles of Rumex crispus L. (curled dock) reduced the total yield per panicle of seeds and fruits in comparison to control plants. However, the mean weight per seed was progressively higher as a greater proportion of the whorls was removed.For untreated plants, seeds borne toward the tips of branches were always lighter than those found near the junctions of branches with the main rachis. Seeds from the lower portion of the panicle were generally larger than those from the upper branches. On treated plants individual seed weight became less variable over the whole panicle.Although seeds from all treatments were equally viable, the larger seeds from treated plants exhibited a greater amount of dormancy under several germination regimes. This increased dormancy might be attributed to the thicker investing structures of larger seeds.

The effect of defoliation on seed production by capeweed (Arctotheca calendula)

1973 ◽  
Vol 13 (65) ◽  
pp. 676 ◽  
Author(s):  
JG McIvor ◽  
DF Smith
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Yield Components ◽  
Seed Weight ◽  
Leaf Removal ◽  
Late Flowering ◽  
Individual Seed ◽  
Number Of Seeds

Two experiments were done in pots to assess the effect of defoliation at different times on the seed yield of capeweed (Arctotheca calendula). Yield components measured were: number of seedheads per plant, number of seeds per seedhead, number of seeds per plant, and weight of individual seeds. Of the components of yield, number of florets per seedhead and individual seed weight were maintained under all treatments; number of seedheads and number of seeds per seedhead were more affected by defoliation. Whether grown as spaced plants or in swards, leaf removal did not significantly reduce the number of seeds produced unless combined with bud and flower removal at late flowering only. The results are discussed in relation to the growth and persistence of capeweed in pastures.

Seed production in woodland and isolated trees of Eucalyptus melliodora (yellow box, Myrtaceae) in the South Western Slopes of New South Wales

2000 ◽  
Vol 48 (6) ◽  
pp. 681 ◽  
Author(s):  
G. E. Burrows
Keyword(s):  
Seed Production ◽  
Seed Weight ◽  
Physical Parameters ◽  
Mixed Mating ◽  
Isolated Trees ◽  
South Wales ◽  
Large Numbers ◽  
The Mean ◽  
Viable Seeds ◽  
Number Of Seeds

Seed production in woodland and isolated Eucalyptus melliodora Cunn. ex Schauer trees was investigated. Measurement of physical parameters such as mean capsule weight, mean seed weight and mean ratio of the weight of the capsule contents to the weight of the empty capsule showed no significant differences between woodland and isolated trees. In contrast, reproductive output as measured by mean number of seeds per capsule, mean number of seeds per 10 g of capsule contents and mean seed weight as a percentage of the weight of the capsule contents, was significantly lower (45–48% less) in isolated trees than in woodland trees. Mean percentage seed germination was also significantly lower (14% less) in the isolated trees and the mean number of viable seeds per 10 g of capsule contents was only 38% of the woodland trees. These results indicate that E. melliodora, like many eucalypts, has a mixed mating breeding system with preferential outcrossing but is also capable of self pollination leading to a reduction in seed yield and viability. The woodland and isolated trees produced a mean of 4.6 and 2.1 seeds per capsule, respectively. It would be relatively easy to collect large numbers of seeds from isolated trees of E. melliodora and subsequently propagate potentially genetically inferior plants.

Variable paths to seed production within the Kangaroo Valley cultivar of Lolium perenne

1991 ◽  
Vol 42 (1) ◽  
pp. 151 ◽  
Author(s):  
SG Shah ◽  
CJ Pearson ◽  
AC Kirby
Keyword(s):  
Seed Production ◽  
Lolium Perenne ◽  
Seed Yield ◽  
Low Temperatures ◽  
Seed Weight ◽  
Floral Development ◽  
Dry Weight ◽  
Daily Rate ◽  
Spike Number ◽  
The Mean

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.

Effect of burr burial on seed production of Trifolium subterraneaum subsp. brachycalycinum and other annual legumes

1986 ◽  
Vol 26 (1) ◽  
pp. 59 ◽  
Author(s):  
MDA Bolland ◽  
WJ Collins
Keyword(s):  
Seed Production ◽  
Sandy Soil ◽  
Seed Weight ◽  
Trifolium Subterraneum ◽  
Annual Legumes ◽  
Seed Yields

On sandy soil near Esperance, W.A., prevention of burr burial compared with covering developing burrs with sand drastically reduced the seed production of three subspp. of Trifolium subterraneum (brachycalycinum, subterraneum and yanninicum) and of T. israeliticum by reducing burr production and seed weight. However, T. globosum produced similar amounts of seed from unburied and buried burrs. On sandy soil at Shenton Park, Perth, W.A., prevention of burr burial also reduced seed production of T. subterraneum subspp. brachycalycinum and subterraneum, this being due to fewer burrs, fewer seeds per burr and lighter seed. For subsp. brachycalycinum, seed yields were two to five times greater from burrs which developed within loose gravel than from those developed over sand (in which fewer burrs were able to bury) as a result of increased production of burrs, more seeds per burr and heavier seed. However, for subsp. subterraneum seed yields were similar from burrs whether developed over gravel or sand.

scholarly journals Morphological characterization and genetic diversity in lentil (Lens culinaris medikus ssp. Culinaris) germplasm

2014 ◽  
Vol 4 (1) ◽  
pp. 70-76
Author(s):  
KU Ahamed ◽  
B Akhter ◽  
MR Islam ◽  
MR Humaun ◽  
MJ Alam
Keyword(s):  
Seed Weight ◽  
Female Flower ◽  
Morphological Characterization ◽  
Flower Initiation ◽  
Mean Values ◽  
Maximum Value ◽  
Cluster Distance ◽  
The Mean ◽  
100 Seed Weight ◽  
Number Of Seeds

Genetic divergence of 110 lentil germplasm with checks was assessed based on morphological traits using multivariate analysis. Mahalanobis generalized distance (D2) analysis was used to group the lentil genotypes. Significant variations among lentil genotypes were observed in respect of days to 1st flowering, days to 50% flowering, days to maturity, plant height, and number of pods per peduncle, number of pods per plant, number of seeds per plant, 100 seed weight and yield per plant. Considering the mean values, the germplasm were grouped into ten clusters. The highest number of genotypes (17) was in cluster X and lowest (5) both in cluster II and IV. Cluster IV had the highest cluster mean for number of pods per plant (297.08), number of seeds per plant (594.16), 100 seed weight (1.44 g) and yield per plant (8.53 g). Among them, the highest inter-cluster distance was obtained between the cluster IV and I (24.61) followed by IV and III (22.33), while the lowest was between IX and II (1.63). The maximum value of inter-cluster distance indicated that genotypes belonging to cluster IV were far diverged from those of cluster I. The first female flower initiation was earlier in BD-3812 (49 days) in cluster I and cluster IV had highest grain yield per plant (8.53). BD-3807 produced significant maximum number of pods per plant (298.40) in cluster IV. DOI: http://dx.doi.org/10.3329/ijarit.v4i1.21095 Int. J. Agril. Res. Innov. & Tech. 4 (1): 70-76, June, 2014

scholarly journals Heliotropism and water availability effects on flowering dynamics and seed production in Macroptilium lathyroides

2006 ◽  
Vol 28 (2) ◽  
pp. 45-52 ◽  
Author(s):  
Armando Martins dos Santos ◽  
Luis Mauro Gonçalves Rosa ◽  
Lucia Brandão Franke ◽  
Carlos Nabinger
Keyword(s):  
Seed Production ◽  
Water Availability ◽  
Yield Components ◽  
Seed Weight ◽  
Field Capacity ◽  
Leaf Movements ◽  
Independent Effects ◽  
Total Seed ◽  
Macroptilium Lathyroides ◽  
Response To Water

The experiment was carried out in pots in a glasshouse, with one plant per pot and nine repetitions per treatment. The treatments consisted of free or restricted leaves, submited to 90-100% or 60-70% soil field capacity (FC). Only independent effects of water availability or leaf movement were observed on yield components. Plants under well-watered conditions and with freely orienting leaves were taller, and had a larger number of ramifications. The greater development favored the setting of a higher number of inflorescences per plant in these treatments. This behavior resulted in a high number of flowers, green and mature legumes per plant, thus resulting in high seed production which was the most evident response to water availability. Although individual seed weight was higher in the water stress treatment, total seed production was higher for well-watered plants, with no statistically significant effect of leaf movements.

scholarly journals Effect of Seeding Rate On Growth And Yield Of Okra (Abelmoschus Esculantus) In Zuru Northern Guinea Savanna Of Nigeria

2018 ◽  
Vol 6 (02) ◽  
Author(s):  
Yohanna J, A. ◽  
Muhammad A, M.
Keyword(s):  
Block Design ◽  
Total Yield ◽  
Growth And Yield ◽  
Land Resource ◽  
Seeding Rate ◽  
Randomized Complete Block Design ◽  
Number Of Leaves ◽  
Resource Space ◽  
Plant Stand ◽  
The Mean

Field experiment was carried out during 2010 rainy season to find the effect of seeding rate on the growth and yield of okra (Abelmuschus esculentus) in Zuru Northern Guinea Savannah. Zuru is located in Zuru Local government area of Kebbi State (Latitude 11o 251 to 11o 551 North and Longitude 4o 51 to 5o 251 East of the equator). The experiment consisted of three treatments that is planting okra at one plant per stand (S1), two plants per stand (S2) and three plants per stand (S3). The experiment was laid out in randomized complete block design (RCBD) and the treatments replicated three time. The result of the experiment has shown that plant height and number of leaves/plant at 3, 6 and 9 weeks after planting (    WAP) were significantly influenced by seeding rate (P<0.05). At 3, 6 and 9 WAP tallest plants were obtained from okra plants planted at three plants/stand (27.83, 54.0 and 77.0cm) respectively followed by okra planted at two plant/stand (24.77, 50.67 and 74.33 leave/plant respectively ). However, more number of leaves/plant were obtained from okra plant at one plant/stand (9.67, 24.67 and 48.0 leaves/plant respectively) followed by okra planted at two plants/stand (8.33, 18.33 and 36.33 leaves/plant respectively). Seeding rate had significant influence on time of 50 percent flowering with one plant/stand first attaining 50 percent flowering stage just within 36.33 days followed by okra planted at two plants/stand (38 days). The mean fresh fruit yield of okra was also significantly influenced by seeding rate with the highest yield of fresh fruits obtained from three plants/stand (83.34/ha) followed by okra planted at two plants/stand (55.56/ha). However, the result of the findings recommends that, okra should be planted at two plants/stand for medium sized and marketable okra fresh fruits since at three plants/stand leads to the production of undersized fresh fruits which do not often attract customers. At one plant/stand, there seemed to be early fruiting and bigger sized fresh fruits but low total yield due to underutilization of land resource/space. Planting at one plant/stand should therefore be avoided

scholarly journals Seed Germination Variation among Crop Years from a Pinus sylvestris Clonal Seed Orchard

2019 ◽  
pp. 1-14
Author(s):  
Melusi Rampart
Keyword(s):  
Seed Germination ◽  
Seed Weight ◽  
Seed Orchard ◽  
Climatic Conditions ◽  
Thermal Time ◽  
Base Temperature ◽  
Germination Capacity ◽  
Seed Collection ◽  
Clonal Seed Orchard ◽  
The Mean

Maternal effects were assessed by germinating seeds sourced over multiple years from the same cloned mother trees, comparing germination capacity and rate between crop years. The relationships between climatic variables, seed characteristics and germination capacity were determined, and thermal time parameters were used to predict seed dormancy release and germination under the climatic conditions in the year after seed collection. There were significant differences in seed weight (P < 0.05), seed length and embryo occupancy (both P < 0.001) among crop years. Temperature during the seed development period explained 70% of the variation in seed weight and 63% of the variation in embryo occupancy. Germination capacity was significantly (P <0.001) different among crop years, among temperatures and among chilling durations, and thermal time requirements for germination increased from older (2007) to younger (2012) seeds. The mean base temperature without chilling was 7.1°C, while after chilling it was 4.6°C and 3.6°C for four and eight weeks chilling respectively. The mean thermal time to 50% germination without chilling was 135.1°Cd, while after chilling it was 118.3°Cd and 154.0°Cd for four and eight weeks chilling respectively. This experiment demonstrates that year-to-year differences in the environment experienced by mother trees during seed maturation can affect seed germination characteristics.

ETHEPHON AS A CHEMICAL HARVESTING AID FOR THE LATE SEASON HIGHBUSH BLUEBERRY COVILLE

1977 ◽  
Vol 57 (4) ◽  
pp. 1099-1102 ◽  
Author(s):  
F. R. FORSYTH ◽  
D. L. CRAIG ◽  
R. STARK
Keyword(s):  
Total Yield ◽  
Soluble Solids ◽  
Yield Reduction ◽  
Average Weight ◽  
Highbush Blueberry ◽  
Ripe Fruit ◽  
Titratable Acid ◽  
Berry Weight ◽  
The Mean ◽  
Solids Content

Single applications of ethephon (1,000 pm) were made at three treatment dates to 20-yr-old Coville highbush blueberry plants. Berry weight, titratable acid, soluble solids content and yield were recorded. Average weight per berry was not consistently different in treated berries than in untreated but in both years the second and third sprays decreased the mean berry weight faster than occurred in the controls or first spray. Total yield was only slightly affected by treatment, indicating that a yield reduction would not be expected through the use of ethephon. Ethephon increased the rate at which the soluble solids and titratable acid (as citric) reached the normal level for ripe fruit.

scholarly journals Phenotypic Variation in Fruit Morphology among Provenances ofSclerocarya birrea(A. Rich.) Hochst.

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Idah Mkwezalamba ◽  
Chimuleke R. Y. Munthali ◽  
Edward Missanjo
Keyword(s):  
Seed Weight ◽  
Fruit Weight ◽  
The Other ◽  
Fruit Traits ◽  
Fruit Length ◽  
Sclerocarya Birrea ◽  
The Mean ◽  
Quality Of Products ◽  
Selection Of

Sclerocarya birrea(A. Rich.) Hochst. is a multipurpose fruit tree which is very useful in providing food security and meeting nutritional and economic needs. This study was conducted to assess eighteen provenances ofSclerocarya birreaplanted in Mangochi, Malawi. The trial was assessed for fruit traits at fifteen years of age. There were significant (P<0.001) variations among the provenances in number of fruits, fruit weight, pulp weight, seed weight, fruit length, and diameter. Magunde provenance from Mozambique had the highest mean number of fruits, 2196 ± 200. Mangochi and Moamba provenances from Malawi and Mozambique were the most outstanding in the other parameters measured attaining the mean fruit weight of 20.89 ± 0.25 g and 25.67 ± 0.67 g, pulp weight of 25.70 ± 0.08 g and 21.55 ± 0.83 g, seed weight of 4.81 ± 0.35 g and 4.12 ± 0.18 g, fruit length of 2.61 ± 0.14 cm and 2.33 ± 0.07 cm, and fruit diameter of 2.33 ± 0.15 cm and 1.97 ± 0.08 cm, respectively. There was no significant (P>0.05) correlation between number of fruits and the other fruit traits. However, there were significant (P<0.05) and strong positive relationships between fruit weight and pulp weight (r=0.987) and fruit length and diameter (r=0.775). This suggests that fruit weight can be used indirectly for selection of pulp. Further studies should investigate fruit taste quality of products from the fruits.

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