Assessment of RAPD marker frequencies over cycles of recurrent selection for pigment concentration and percent solids in red beet (Beta vulgaris L.)

Betalain pigments, composed of the red-violet betacyanins (BC) and the yellow betaxanthins (BX), provide an excellent natural alternative to synthetic red dyes. The objective of this investigation was to evaluate eight cycles of recurrent selection in two red beet (Beta vulgaris L.) populations selected for high total betalain pigment concentration and both high (HPHS) and low (HPLS) total dissolved solids (TDS). Remnant seed was planted in a randomized complete block design in replicated trials at two locations in 1994. Beet roots were sampled at harvest for concentrations of BC, BX, and TDS. Highly significant differences among cycles for BC, BX, BC:BX, total pigment, and TDS were observed. Average gains per cycle were 13.15 and 4.06 mg per 100 g fresh weight for BC and BX in HPHS, and 7.59 and 2.61 mg per 100 g fresh weight for BC and BX in HPLS, respectively. Total pigment increased about 200 % in both populations. Selection for low TDS was ineffective, while only a mild response was detected from selection for high TDS. Since betalain pigments are formed following glycosylation of cyclodopa and betalamic acid, sugar molecules are associated with pigment biosynthesis. Simultaneous selection for high pigment and low TDS may therefore be metabolically incompatible. Our findings demonstrate betalain pigment concentration responds favorably to recurrent selection: however. a concomitant reduction in TDS is not a feasible selection goal.

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Directional RAPD Marker Frequency Changes in Two Divergently Selected Beet Populations

HortScience ◽

10.21273/hortsci.30.4.841c ◽

1995 ◽

Vol 30 (4) ◽

pp. 841C-841

Author(s):

K.A. Eagen ◽

I.L. Goldman

Keyword(s):

Rapd Markers ◽

Recurrent Selection ◽

Rapd Marker ◽

Family Selection ◽

Chi Square ◽

Selection Scheme ◽

Red Beet ◽

Frequency Changes ◽

Marker Frequency ◽

Linear Trends

In the past 20 years, betalain pigments found in red beet (Beta vulgaris L.) have been adopted for use as natural red food coloring. In an effort to develop red beet populations with elevated levels of betalain pigment, recurrent half-sib family selection for high pigment and both high and low solids was practiced for seven cycles, resulting in the development of a high pigment–high solids (HPHS) and a high pigment–low solids (HPLS) population. Thirty-one randomly selected decamer primers were chosen to assess RAPD marker frequencies on genomic DNA samples isolated from 47 randomly chosen individual plants in each of cycles 1, 3, and 6 in both HPHS and HPLS. A total of 161 RAPD markers were evaluated. Chi-square and regression analyses were performed to determine presence/absence of linear trends in marker frequencies during the selection scheme. Comparisons were made for individual cycles between HPHS and HPLS and among cycles within HPHS and HPLS. Significant linear trends were detected in both cases for key RAPD primers. Chi-square tests revealed a subset of the markers which exhibited significant frequency changes across cycles were associated with selection as opposed to genetic drift. These data demonstrate changes in RAPD marker frequencies with recurrent selection and suggest linkage of RAPD markers to genes controlling pigment and solids in red beet.

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333 RAPD MARKER FREQUENCY CHANGES IN TWO RED BEET POPULATIONS UNDERGOING RECURRENT SELECTION

HortScience ◽

10.21273/hortsci.29.5.478c ◽

1994 ◽

Vol 29 (5) ◽

pp. 478c-478

Author(s):

K.A. Eagen ◽

I.L. Goldman

Keyword(s):

Recurrent Selection ◽

Rapd Marker ◽

Natural Food ◽

Family Selection ◽

Chi Square ◽

Red Beet ◽

Rapd Primer ◽

Pcr Products ◽

Frequency Changes ◽

Linear Trends

Red beet contains betalain pigments recently adopted for use as natural food colorings. In an effort to develop beet populations with higher levels of betalain pigment, recurrent half-sib family selection for high pigment and both high and low solids was practiced in two populations for 7 cycles. PCR-based RAPD marker frequencies were assessed on genomic DNA samples isolated from 47 randomly-chosen individual plants from cycles 1, 3, and 6 in both populations. Number of PCR products per RAPD primer varied, with some yielding up to 5 scorable products. Chi-square and regression analyses were performed to determine presence/absence of linear trends in marker frequencies associated with selection. Significant linear trends in RAPD market frequencies were detected for certain primers both between populations and among cycles. These data demonstrate changes in RAPD marker frequencies with selection and suggest linkage of RAPD markers to genes controlling pigment and solids in red beet.

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Improvement of effectiveness in maize breeding

Acta Agronomica Hungarica ◽

10.1556/aagr.54.2006.3.10 ◽

2006 ◽

Vol 54 (3) ◽

pp. 351-358 ◽

Cited By ~ 2

Author(s):

P. Pepó

Keyword(s):

Recurrent Selection ◽

Genetic Manipulation ◽

Field Testing ◽

Tissue Cultures ◽

Maize Breeding ◽

Breeding Programmes ◽

Speed Up ◽

Selection For

Plant regeneration via tissue culture is becoming increasingly more common in monocots such as maize (Zea mays L.). Pollen (gametophytic) selection for resistance to aflatoxin in maize can greatly facilitate recurrent selection and the screening of germplasm for resistance at much less cost and in a shorter time than field testing. In vivo and in vitro techniques have been integrated in maize breeding programmes to obtain desirable agronomic attributes, enhance the genes responsible for them and speed up the breeding process. The efficiency of anther and tissue cultures in maize and wheat has reached the stage where they can be used in breeding programmes to some extent and many new cultivars produced by genetic manipulation have now reached the market.

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