HERITABILITY OF SEED YIELD COMPONENTS AND SOME VISUALLY EVALUATED CHARACTERS IN REED CANARYGRASS

1966 ◽  
Vol 46 (1) ◽  
pp. 51-58 ◽  
Author(s):  
S. G. Bonin ◽  
B. P. Goplen

Heritability estimates were obtained for the three principal components of seed yield in reed canarygrass (Phalaris arundinacea L.): seed shattering, seed weight per panicle, and number of panicles per plant. The heritability estimates were based on Lush’s progeny–parent regression method using data from 32 clones and their open-pollination progenies. Estimates were 91% for seed shattering, 74% for seed weight per panicle, 70% for number of panicles per plant, and 36% for theoretical net yield. Four visually evaluated characters had estimated heritabilities of 81% for spring vigor, 67% for growth habit, 88% for panicle color, and 81% for panicle type.Phenotypic correlations were calculated between all pairs of characters studied, using clonal means. Seed yield was found to be significantly correlated with shattering percentage and seed weight per panicle but not with number or panicles per plant. Low shattering was associated with low spring vigor, few panicles per plant, and upright growth habit. Shattering percentage was not significantly correlated with seed weight per panicle.

2010 ◽  
Vol 14 ◽  
pp. 67-73
Author(s):  
J.A.K. Trethewey ◽  
M.P. Rolston

In cereals, the importance of the flag leaf for contributing carbohydrate during seed fill is well documented. However, in ryegrass this relationship is not so clear. This paper reports on an investigation of the effect on seed yield components of reduced photosynthetic capacity to the flag leaf, stem and head of perennial ryegrass (Lolium perenne). The hypothesis was that reduced photosynthetic capacity of the flag leaf does not affect seed yield components in perennial ryegrass. Following flowering, photosynthetic capacity was reduced by defoliation or shading the flag leaf, stem, or head of individual tillers. Seed yield components were measured at harvest. Reduced photosynthetically active radiation (PAR) to the flag leaf and stem did not affect thousand seed weight or seed yield when compared with control plants whereas reducing PAR to the head had a significant effect. The seed head itself may be more important than the flag leaf during seed fill, but when the seed head is shaded substantial re-mobilisation of stored carbohydrates can occur. Keywords: flag leaf, green leaf area, Lolium perenne, photosynthetically active radiation, seed fill, seed yield, thousand seed weight, water-soluble carbohydrates


1970 ◽  
Vol 50 (1) ◽  
pp. 103-106 ◽  
Author(s):  
B. E. TWAMLEY

Several hundred two-year-old nursery plants originating in the early-type trefoil cultivar Maitland were rated for flowering maturity, morphological features and growth pattern. Open-pollination seed was collected from these and 100-seed weight determinations were made.The experimental material was organized into two sections for testing purposes. In one, the effect of maternal maturity on the seedling vigor of the progeny was studied and in the other the effect of maternal morphology. Each section was made up of five classes, varying either in maturity or in morphology. Each class contained either nine or ten progeny lines. The range in seed size was similar for all classes. No relationship was found between maturity, morphological type or growth habit of the maternal parent on the one hand and the seedling vigor rating of their progeny at six and ten weeks of age on the other.The breeding implications of these findings are discussed.


1977 ◽  
Vol 88 (3) ◽  
pp. 605-614 ◽  
Author(s):  
P. D. Hebblethwaite

SUMMARYThe effects of irrigation and nitrogen on S. 23 perennial ryegrass grown for seed were investigated in a series of field experiments from 1972 to 1974. Irrigation significantly increased seed yield by 16% in 1972 and 52% in 1974 but had no effect in the wet year of 1973. In 1972 maximum deficit reached 110 mm at the end of July and coincided with anthesis. Consequently the yield response was due to an increase in number of seeds per unit area and no other seed yield component was affected. In 1974 peak deficit also reached about 100 mm but started to build up rapidly very early in the season and had reached 80 mm by the time that the first ears emerged. Consequently the yield response was due to increases in number of fertile tillers, number of seeds per unit area and 1000-seed weight.Irrigation had no significant effect on number of florets or seeds, except in 1974 when percentage of florets which produced seed was increased by 2%.Irrigation had some effect on threshed straw yields, total dry matter, harvest index and total number of tillers but where this occurred the response was much smaller than that of seed yield which indicates that irrigation had greater effects on the reproductive development of the crop than on yield of dry matter and tillering patterns. Increasing the quantity of nitrogen from 0 to 80 kg/ha increased seed yields, all seed yield components except 1000-seed weight, threshed straw yields and total dry matter and number of tillers at most sampling dates. Increasing the quantity of nitrogen from 80 to 160 kg/ha had little further effect on the above components except in 1972 where seed yields were significantly decreased.In 1972 number of florets was increased and percentage of florets which produced seed decreased with increasing quantities of nitrogen.


2014 ◽  
Vol 6 (2) ◽  
pp. 605-611
Author(s):  
M. K. Jat ◽  
O. P. Chaudhary ◽  
H. D. Kaushik ◽  
Sunita Yadav ◽  
A. S. Tetarwal

The effect of different modes of pollination on quantitative and qualitative parameters of Egyptian clover, Trifolium alexandrinum L. was studied at Forage Section, Department of Genetics and Plant Breeding, CCS, Haryana Agricultural University, Hisar during 2012 and 2013. Maximum seed setting (81.5%) was recorded in A. mellifera pollination with an 8 frame colony (BP-8F) followed by 4 frame colony (BP-4F) (75.1%), open pollination (OP) (73.8%) and 2 frame colony (BP-2F) (71.5%). Maximum seed yield (2662.3 seeds) was observed in treatment BP-8F followed by BP-4F (2373.8), OP (2316.3) and BP-2F (2235.5). Still lower yield of 2103.0 seeds was found in hand pollination (HP) treatment that was significantly higher than the without insect pollination (WIP) treatment (1114.2). Minimum 1000-seed weight was observed in WIP (2.64 g). The seed weight of BP-4F (3.30), HP (3.20), BP-2F (3.17) and OP (3.03), the heaviest seeds were recorded in BP-8F (3.62 g/1000 grains) and it was at par with the treatment BP-4F (3.30 g). Highest seed germination per cent was recorded in BP-8F (94.7) followed by OP (90.7%). Lowest germination was found in WIP (84.7%). Though some work has been done on this aspect in India but comprehensive pollination studies has not been worked out.


Genetika ◽  
2013 ◽  
Vol 45 (2) ◽  
pp. 553-563
Author(s):  
Zeljko Lakic ◽  
Dejan Sokolovic ◽  
Snezana Babic ◽  
Svetko Vojin ◽  
Jela Ikanovic ◽  
...  

The aim of this study was to examine genetic variability, heritability and correlation of seed yield components and seed yield of progenies of autochthonous populations and cultivars of perennial ryegrass, and that on the basis of these results distinguish genotypes that would be later used in the creation of new local cultivars of perennial ryegrass. Research was carried out on experimental fields and laboratories of the Agricultural Institute of Republic of Srpska in Banja Luka in 2007. and 2008., on 6 natural populations of perennial ryegrass collected in Bosnia and Herzegovina and two cultivars, Maja and Calibra as standard. Following parameters were analyzed: number of generative tillers per plant, time of flowering, spike length, number of spikelets per spike, seed yield per spike and plant and 1000 seed weight. Analysis of the results of the number of generative tillers per plant indicates a statistically significant difference in the studied populations and cultivars of perennial ryegrass. The highest average number of tillers per plant was found in the cultivar Maja (193.8), and the least number was detected in population Dragocaj (78.9), so statistical differences were highly significant. The longest period to beginning of flowering was determined in cultivar Calibra (56.5 days) and the shortest in population Laminci (43 days). The average length of spike of perennial ryegrass in the studied population was 22.78 cm and was significantly lower than cultivar Maja. Statistically significant differences between populations and variety Maja in the number of spikelets per spike were detected. The average seed yield per spike of studied populations was in level with cultivar Maja and 37.5% higher compared with variety Calibra. In the studied populations of perennial ryegrass seed yield ranged from 5.21 g (Dragocaj population) to 15.40 g (Kupres population). Weight of 1000 seeds was highest in the variety Calibra (2.60 g) and lowest in population Maglajani (1.94 g). Proportion of genetic to phenotypic variance for time of flowering, the number of generative tillers, seed yield per spike and plant and 1000 seed weight indicate that the variability of these traits in this collection of genotypes, largely derived from plant genotype. In this investigation, the presence of a highly significant positive genetic correlation was found between time of flowering and spike length (0.98), time of flowering and 1000 seed weight (0.97), number of generative tillers and seed yield per plant (0.91) and spike length and 1000 seed weight (0.98).


2002 ◽  
Vol 45 (4) ◽  
pp. 401-412 ◽  
Author(s):  
Fábio Pandini ◽  
Natal Antonio Vello ◽  
Ângela Celis de Almeida Lopes

The objective of this research was to quantify heterosis of agronomic traits and evaluate direct and indirect correlations among seed yield and other traits. A diallel involving six parents was grown in two localities. Seed yield (PG), one-hundred seed weight (PCS), number of pods per plant (NV), weight of aerial part of the plant (PPA), harvest index (IC) and number of seeds per pod (NGV) were evaluated. Positive values of heterosis were detected for all traits. Estimates of heterosis components were significative for most traits, showing effects of aditivity and dominance. The specific heterosis was more important than the variety heterosis, mainly in the locality Anhembi. MTBR-95-123800 presented the best potential per se and as parent in crosses, but it was excelled by some of the hybrids in the two localities. Number of pods per plant demonstrated to be suitable for indirect selection for PG.


1996 ◽  
Vol 36 (2) ◽  
pp. 189 ◽  
Author(s):  
L Ramirez ◽  
JB Hacker

The effect of fertiliser nitrogen (N) and season (spring or autumn seed harvests) on tiller appearance, development and survival, and seed production in D. eriantha was investigated in a trial in south-east Queensland. In both spring and autumn, rate of tillering was maximal within the first week after cutting and declined rapidly thereafter, regardless of the level of applied N. Rate of tillering was greater in spring than in autumn. Tiller survival decreased as tiller emergence was delayed, and with increasing levels of applied N. At seed harvest, early-emerged tillers were consistently taller, heavier, thicker, and more fertile than late-emerged tillers, and they contributed most of the inflorescences. Fertility of all tillers was increased by application of N, particularly in spring. Seed yield, percentage seed set, and 1000-seed weight were larger in early-emerged tillers, which also bore the biggest inflorescences with the most spikelets per inflorescence, although spikelet number per unit raceme length was lower than on inflorescences borne on late-formed tillers. In general, the effect of N on seed yield components (inflorescence size, 1000-seed weight and seed set) was not significant. Early-emerged tillers contributed more than 70% of the total seed yield in both seasons.


2012 ◽  
Vol 57 (3) ◽  
pp. 111-120 ◽  
Author(s):  
Valiollah Rameeh

To estimate the general and specific combining ability (GCA and SCA) effects of plant height, yield components, seed yield and oil content, three testers and six lines of spring type of rapeseed varieties were crossed using line ? tester fashion. Significant mean squares of parents and crosses for all the traits indicated significant genetic variation among the parents and their F1 crosses. Significant mean squares of parents vs crosses revealed significant average heterosis for all the traits except seeds per pod, 1000-seed weight and oil content. High narrow-sense heritability estimates for all the traits except seeds per pod, indicating the importance of additive genetic effects for these traits. Due to more importance of additive genetic effects for most of the traits, only a few of the crosses exhibited significant SCA effects. A significant positive correlation between seed yield and some of yield components including pods on main axis, pods per plant and 1000-seed weight indicates that these traits can be used as suitable selection criteria for improving of seed yield. The crosses including Opt ? R01, RG06 ? R01, RG06 ? R08 and RGS3 ? R08 with 3241.91, 3213.68, 3334.28 and 3237.45 kg ha-1 of seed yield detected as prior combinations for improving of this trait and all of these combinations had also positive SCA effect for this trait.


2015 ◽  
Vol 4 (2) ◽  
pp. 330-340
Author(s):  
Sadia Shaukat ◽  
Dr Raziuddin ◽  
Fahim Ullah Khan ◽  
Ibni Amin Khalil

To investigate genetic variability and heritability, eight Brassica napus genotypes were evaluated at New Developmental Research Farm, Faculty of Agriculture. Peshawar University, during 2010-11. Analysis of variance revealed significant differences (P≤0.01) among Brassica napus genotypes for all the studied characters. Mean values showed that maximum primary branches plant-1 (15) was observed for genotype PGRI-8, plant height (220.66 cm) for genotype CH-6 and PGRI-8, pods main raceme-1 (96.33) for genotype CH-1, pods plant-1 (994) for genotype PGRI- 8, pod length (8.3 cm) for genotype PGRI- 7, seeds pod-1 (27) for genotype CH-1, 1000-seed weight (3.97 g) for genotype CH-2, and seed yield plant-1 (91.1 g) for genotype PGRI-8. In t terms of heritability values, high broad sense heritability estimates were observed for primary branches plant-1 (0.83), plant height (0.78), pods main raceme-1 (0.65), seeds pod-1 (0.61), 1000-seed weight (0.61), while moderate heritability values were recorded for pod length (0.57), pods plant-1 (0.55), and seed yield plant-1 (0.50). In conclusion, the significant differences among Brassica napus genotypes showed that there is sufficient variability for effective selection. The trend of heritability (moderate to high) in the present study indicates that there is more genetic control and selection should lead to quick improvement. Furthermore genotype PGRI-8 surpassed all other genotypes in yield and yield component and could be used in future breeding programs. DOI: http://dx.doi.org/10.3126/ije.v4i2.12661 International Journal of Environment Vol.4(2) 2015: 330-340


1995 ◽  
Vol 73 (3) ◽  
pp. 505-511 ◽  
Author(s):  
B. Kahn ◽  
J. A. Silander Jr. ◽  
H. L. Reynolds ◽  
M. L. Cain

There is much spatial and temporal variation for reproductive output in white clover (Trifolium repens L.), yet little is known about the control of this variation or whether there exist tradeoffs among components of seed yield. To examine these issues, seed yield components and vegetative biomass were measured on replicates of seven white clover genotypes planted in a common garden plot. Significant genetic differences among clones were found for biomass and for five of seven reproductive characters, including number of inflorescences, number of florets per inflorescence, number of fruits per infructescence, number of (late-maturing) seed per fruit, and seed weight in early-maturing fruits. Thus, there is considerable potential for natural or artificial selection to act on vegetative and reproductive characters in white clover. In addition to these genetic effects, we observed temporal variation for number of florets per inflorescence, number of fruits per infructescence, and seed weight in late-maturing fruits. Finally, analyses of phenotypic, genetic, and microenvironmental correlation coefficients revealed few pairs of traits with significant negative correlations. This suggests that few tradeoffs in resource allocation patterns existed for the phenotypic characters examined. Key words: Trifolium repens, genetic variation, seed yield components, tradeoffs, phenotypic correlation, genetic correlation.


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