Combining ability and heterosis for root structure and graft-related traits of interspecific Cucurbita rootstocks

SummaryPlatelets deprived of calcium and incubated at 37° C for 10 min lose their ability to bind fibrinogen or aggregate with ADP when adequate concentrations of calcium are restored. Since the calcium complex of glycoproteins (GP) IIb and IIIa is the presumed receptor for fibrinogen, it seemed appropriate to examine the behavior of these glycoproteins in incubated non-aggregable platelets. No differences were noted in the electrophoretic pattern of nonaggregable EDTA-treated and aggregable control CaEDTA-treated platelets when SDS gels of Triton X- 114 fractions were stained with silver. GP IIb and IIIa were extracted from either nonaggregable EDTA-treated platelets or aggregable control platelets with calcium-Tris-Triton buffer and subjected to sucrose density gradient centrifugation or crossed immunoelectrophoresis. With both types of platelets, these glycoproteins formed a complex in the presence of calcium. If the glycoproteins were extracted with EDTA-Tris-Triton buffer, or if Triton-solubilized platelet membranes were incubated with EGTA at 37° C for 30 min, GP IIb and IIIa were unable to form a complex in the presence of calcium. We conclude that inability of extracted GP IIb and IIIa to combine in the presence of calcium is not responsible for the irreversible loss of aggregability that occurs when whole platelets are incubated with EDTA at 37° C.

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Combining ability for some salinity tolerance traits in rice

Bangladesh Journal of Agricultural Research ◽

10.3329/bjar.v32i2.301 ◽

2007 ◽

Vol 32 (2) ◽

Author(s):

Pranah Kumar Saha Ray ◽

M Amirul Islam

Keyword(s):

Salinity Tolerance ◽

Combining Ability

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COMBINING ABILITY FOR INHERITANCE OF ECONOMIC TRAITS IN OPIUM POPPY (Papaver somniferum L.)

Bangladesh Journal of Plant Breeding and Genetics ◽

10.3329/bjpbg.v24i2.17000 ◽

2011 ◽

Vol 24 (2) ◽

pp. 01-08

Author(s):

B. Kumar ◽

N. K. Patra

Keyword(s):

Combining Ability ◽

Diallel Cross ◽

Papaver Somniferum ◽

Opium Poppy ◽

Economic Traits ◽

Degree Of Dominance ◽

Parental Material ◽

The Mean ◽

Per Se ◽

Important Medicinal Plant

Opium poppy (Papaver somniferum L.) is an important medicinal plant produces more than 80 alkaloids obtained from the capsules and straw of the plant. The estimate of combining ability gives an indication of the genetic behaviour of the parental material. It is therefore, desirable to select the parents for hybridization on the basis of their per se performance and combining ability effects. The F1, F2 and their reciprocals of an eight parent diallel cross in opium poppy were studied for combining ability of seven economic traits. The mean sum of squares due to GCA, SCA and reciprocals were significant for all the traits. The magnitude of GCA variances were invariably higher than those of SCA and thus indicating the preponderance of non-additive genetic variances, which was further affirmed by the measure of average degree of dominance i.e. ?(?2s/? 2g). Among the parents VN35I for plant height, Sanchita and VG26 for capsules per plant, VN23, VN35I and Vivek for capsule index, VG26 and Sanchita for seed and straw yield per plant, and VN35I and VG20 for morphine content were found good general combiners. Earliness being a desired trait, parent VG20 having significant negative GCA estimates coupled with per se performance can be considered as good general combiner for early flowering. Inclusion of good general combiners in a multiple crossing program or an inter-mating population involving all possible crosses among them subjected to bi-parental mating may be expected to offer maximum promise in breeding for economic traits.DOI: http://dx.doi.org/10.3329/bjpbg.v24i2.17000

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Combining ability and heterosis studies across environments in linseed (Linum usitatissimum L.)

Acta Agronomica Hungarica ◽

10.1556/aagr.59.2011.1.9 ◽

2011 ◽

Vol 59 (1) ◽

pp. 87-102 ◽

Cited By ~ 3

Author(s):

S. Sood ◽

N. Kalia ◽

S. Bhateria

Keyword(s):

Seed Yield ◽

Linum Usitatissimum ◽

Combining Ability ◽

Yield Components ◽

Block Design ◽

Linum Usitatissimum L ◽

Randomized Block Design ◽

Component Traits ◽

Parental Lines ◽

Fibre Yield

Combining ability and heterosis were calculated for fourteen lines of linseed in a line × tester mating design using twelve lines and two diverse testers in two different environments. The hybrids and parental lines were raised in a completely randomized block design with three replications to investigate seed and fibre yield and their component traits. Genetic variation was significant for most of the traits over environments. Combining ability studies revealed that the lines KL-221 and LCK-9826 were good general combiners for seed yield and most of its components, whereas LMH-62 and LC-2323 were good general combiners for yield components only. Moreover, KL-221 was also a good general combiner for fibre yield. Similarly, B-509 and Ariane were good general combiners for fibre yield and most of its components. Among the specific cross combinations, B-509 × Flak-1 was outstanding for seed yield per plant and B-509 × KL-187 and LC-2323 × LCK-9826 for fibre yield per plant, with high SCA effects. In general, the hybrids excelled their respective parents and the standard checks for most of the characters studied. Based on the comparison of mean performance, SCA effects and the extent of heterosis, the hybrids LC-2323 × LCK-9826 and B-509 × KL-221 appeared to be the most promising for both seed and fibre yield. Other promising combinations were LC-2323 × KL-210 and B-509 × Ariane for seed and fibre yield, respectively. The superiority of LC-2323, LCK-9826, KL-221, B-509 and Ariane as good general combiners was further confirmed by the involvement of these parents in the desirable cross combinations.

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