Sevilla, Spain.

Jose M. Urbano and Maximiliano Hidalgo.

The 1994-95 season. By far, the drought was the most limiting factor for all the wheat acreage on the Iberian Peninsula in the 1994-95 season. Fortunately, at the time I am writing this report, the period of dry years seems to be finished, and the area is receiving a good amount of rain.

Three locations of winter wheat in the north of Spain were planted without important problems and with good moisture. The same applies for the two locations of spring bread wheat and durums in the northeast of Spain. In the south, we planted four locations of spring bread wheat and durums, with very low moisture, a warning of the terrible year that was coming. The adverse conditions during most of the crop cycle, with a hot and windy spring, caused almost a complete crop failure over wide cereal acreage.

We were able to harvest all the locations, but the yields were so low that they were useful only in the multi-year analysis.

In general, very little disease pressure occurred (in any case, very little yield reduction attributable to diseases). Only powdery mildew was important in some durum varieties in the south, and a few cases of Ophiobolus occurred. Insect damage was higher than usual, with important Mayetiola and thrip attacks that probably went unnoticed by farmers.

In spite of the severe yield reduction, uniformity remained acceptable in most spring and durums locations and enabled us to select for drought tolerance in both species.

Winter wheat locations also suffered from drought, frost, and BYDV. In this case, the uniformity of the trials was unacceptable for making conclusions based on 1-year data.

The 1995 summer nursery went well in general, with unusually low disease levels and good grain-filling conditions.

Varietal development. No durum variety was registered, because most of the Official Trials were lost.

In summer 1995, we submitted for registration two spring bread wheat varieties and one durum, which confirmed their good performance under drought conditions.

Blissworth, Northampton, UK.

Paul Wilson.

The 1994-95 season. In trials harvested in August 1995, three Pioneer high-yielding feed wheat varieties yielded 110 % of the UK check varieties over multiple locations. These varieties are being advanced with seed purification and breeder seed production. Future crossing will place major emphasis on the predominant feed wheat market, while addressing a significant quality segment.

Past research in the UK has been predominantly a testing program with observation nurseries and preliminary and preregistration trials. The material was accessed from our French program. However, climatic and disease pressure differences have necessitated a more intensive research commitment in the UK, and our first F3 headrow nursery was sown in the autumn of 1995.

Data collection. The UK Station will be using Husky hand-held PC's to collect trial data in the field and plot weights and moisture readings on the combine, using a Pioneer software package. Data will be uploaded to a PC from the Husky and then sent to Pioneer USA for analysis and reporting.


WESTERN PLANT BREEDERS, INC.

8111 Timberline Drive, Bozeman, MT, 59715 USA.

Southern research.

Kim Shantz, Doug Holen; Chandler, AZ, USA.

Two hard red spring wheats `Brooks' and `Cuyama' were released recently for production in the San Joaquin Valley of California. Brooks is similar to `Yecora Rojo', but has better resistance to the prevalent races of leaf rust and is outyielding Yecora Rojo by about 10 %. Cuyama has good tolerance to the prevalent races of leaf rust and has better yield than Brooks. The quality of both wheats is similar to that of Yecora Rojo.

Two durums were released for the southwest desert area. `Kofa' is a replacement for `WestBred 881', with greater yield stability and improved gluten strength. `Cortez' is a replacement for `WestBred Turbo'. Cortez has higher protein, improved semolina color, better lodging resistance, and better blackpoint tolerance when compared to W.B. Turbo.

Mike DeVries has moved from our southern research office to Bozeman, where he will coordinate WPB's marketing and seed production programs. It's nice to have someone in marketing who has been down in the trenches with the breeding staff!

Doug Holen joined our southern research office in May as a research agronomist. Doug received a Master's degree from Montana State University, where his major professor was Dr. Phil Bruckner.

Northern research.

Dale Clark, Craig Cook, Earl Giard, and Jeanne Heilig; Bozeman, MT, USA.

Two hard red spring wheats, `WestBred 936' and `Fergus', and one soft white spring, `Vanna', were released for the Pacific Northwest. The variety `Border' was released as an early-maturing, high protein, HRSW for the sawfly-problem areas of Montana. Both WestBred 936 and Fergus are semidwarfs, have high quality protein, and are resistant to shatter. Vanna has shown to be a competitive variety, especially under moisture stress conditions.

Jeanne Heilig has taken a permanent position with Western Plant Breeders as the director of our quality lab. Jeanne worked at WPB for the past 2 years, while completing a Master's degree at Montana State University. Jeanne's thesis involved studying sawfly damage in relation to the plant available water holding capacity (PAWHC) of soil. There appears to be a strong negative correlation between sawfly damage and the PAWHC. The greatest sawfly damage was found in heavy clay and/or light sandy soils, where water is less available to the plant.

Midwest research.

Greg Fox, Fargo, ND, USA.

WPB will soon release the scab-tolerant HRSW `Sharpshooter' for the Minnesota-North Dakota region. The scab resistance for Sharpshooter came from `Sumai-3'.


ITEMS FROM ARGENTINA

BIOLOGICAL RESOURCES INSTITUTE. INTA

Las Caba-as y Los Reseros s/n, (1712) Villa Udaondo, Castelar, Pcia. de Buenos Aires, Argentina.

Breadmaking quality and yield performance of 1BL-1RS germplasm.

G. Tranquilli, L. Bullrich, L. Pfluger, E. Suarez, and A. Barneix.

Rye (S. cereale). introgression into bread wheat (T. aestivum L. em Tell) was used in order to obtain disease resistance. The 1BL-1RS translocation has been the most exploited in wheat breeding programs, because it carries resistance genes to rusts and mildew. This translocation also is reported to increase yield potential, but decreases breadmaking quality.

The effects of the 1BL-1RS translocation chromosome on breadmaking quality and agronomic traits were evaluated in two kind of materials: isogenic lines for the 1BL-1RS translocation and Argentinian varieties.

Evaluation of isogenic lines. Forty isogenic lines for the wheat/rye translocation 1BL-1RS were obtained after six generations of selfing heterozygous genotypes (1B : 1BL-1RS), derived from an F1 of `Chinese Spring x Sinvalocho MA'. The original cross (a `Bobwhite' derivative with the 1BL-1RS translocation) was made by Don Ernesto, INTA . Selection was by cytological markers.

Presence or absence of the rye chromosome arm in isogenic lines also was verified through analysis of secalins and gliadins. Background homogeneity was checked by plant phenotype, HMW and LMW glutenins, and the Est-5 isozyme marker.

Twenty-four isogenic lines (12 families) showing a homozygous background were evaluated in a randomized block design with four replications. Ear-emergence time, plant height, yield, yield components, grain protein concentration, and flour sedimentation (SDS test) were measured.

The wheat/rye translocation increased grain weight and spikelet number per spike, but reduced the spike number per plant. No effect on yield was observed.

A significant reduction in SDS volume was observed in 1BL-1RS carrier lines, with respect to their partners. Only when the Glu-1 score reached 10 was the SDS volume higher than 70 cm, but it was always about 20 % lower than its nontranslocated partner.

Translocated and nontranslocated lines showed a negative association between heading time and yield. Earliness was associated with negative to grain protein concentration. On the other hand, SDS volume was not associated with protein content in the grain.

Evaluation of Argentinian cultivars. In Argentina, the source of the 1BL-1RS translocation has been the CIMMYT germplasm. Twelve Argentinian cultivars possessing the translocation were selected from different origins and heading dates. Each of the cultivars was matched to a nontranslocated variety of similar heading date and origin. Twenty-four selected varieties were included in a randomized block design with six replications. Ear-emergence time, plant height, yield, yield components, grain protein content, flour sedimentation (SDS test), mixing time, and W (alveogram) were measured.

All 1RS-carrier varieties had poorer quality attributes than varieties without the translocation. On average, varieties with the translocation had a 59.15 ml sedimentation volume (ranging from 48.5 ml-64.5 ml), mixing time of 2'77 (ranging from 1'40-3'50), and a W of 200.55 (ranging from 163-268). For the varieties lacking the translocation, the results were 77.92 ml (61.67-90.33), 3'95 (2'50-5'30), and 252.89 (183-327), for SDS, mixing time, and W, respectively. In contrast, the grain protein content was higher in the translocated group.

Although no differences in yield were observed between both groups of varieties, a significant increase in 1,000-kernel weight was shown by 1RS-carrier varieties.

These results clearly show that the 1BL-1RS translocation in Argentinian wheats has an important effect on quality, similar to other wheats around the world, but does not have a remarkable effect on yield.

Study of the resistance to Septoria nodorum in single-chromosome recombinant lines in wheat.

Silvina M. Lewis, Anthony J. Worland1, and Paul Nicholson1.

1Cambridge Laboratory, John Innes Centre, Colney Lane, Norwich NR4 7UJ, UK.

Septoria nodorum (Berk.) Berk. (perfect state Leptosphaeria nodorum Muller) is the causal agent of the glume blotch disease of wheat. Under severe epidemics, the kernels of susceptible wheat cultivars are shrivelled and unfit for milling. Although resistance is a high-priority breeding goal, not enough is known about the genetic patterns that govern resistance to S. nodorum.

Single-chromosome recombinant lines for chromosome 5D of `Synthetic 6x', the complete 5D chromosome of `Chinese Spring', and the long arm of chromosome 5D were developed to study the resistance to S. nodorum glume blotch. The genetic analysis of these lines showed that the resistance was conferred by a single gene located on the long arm of chromosome 5D. Telocentric mapping placed the gene approximately 17 cM from the centromere. Some morphological and biochemical markers also were analyzed. Mapping of the resistance gene in respect to those markers placed the gene near to Ibf-1. The association of the resistance gene with morphological, biochemical, and molecular markers could help breeders select for resistance without the necessity of performing disease screening tests. At present, molecular markers are being screened to find a tightly linked marker to the resistance gene.

When grown under field and glasshouse conditions, the recombinant lines showed variable levels of fertility with the 5D chromosome of the Synthetic 6x linked to low fertility under cool conditions and low light intensities. The low temperature pairing gene (ltp), previously located on chromosome 5D, might possibly be the cause of the low fertility. Further evaluation of the lines will help resolve the fertility problems that have occurred in several recent European winter wheat varieties.

Publications.

Barneix A and Suarez E. 1995. Grain nitrogen concentration and flag leaf free amino acids in wheat. Cereal Res Commun 23:291-297.

Lewis SM, Martinez AJ, and Dubcovsky J. 1996. Karyotype variation in South American Elymus (Triticeae). Int J Plant Sci 157(1):142-150.

Sacco F, Favret E, Suarez E, Solari R, and Saione H. 1995. Spontaneous genetic variation for leaf rust reaction in Sinvalocho MA wheat. J Phytopath 143:251-255.


BIOTECHNOLOGY INSTITUTE - CICV - INTA.

CC 77, 1708 Moron, Castelar, Argentina.

Use of SSR markers in Argentine wheat germplasm characterization.

M.M. Manifesto, A.R. Schlatter, M. Echaide, H.E. Hopp, and J. Dubcovsky.

The use of single-sequence repeat markers is becoming common for fingerprinting and genetic mapping in wheat. Recently, two sets of primers able to amplify microsatellite loci within the gamma-gliadin and LMW-glutenin gene families were described (Devos et al. 1995). Using ditelocentric lines and F2 segregant populations, we confirmed the localization of these markers on chromosomes 1AS and 1BS.

In order to test the feasibility of using these markers to classify the Argentine germplasm bank, 30 representative accessions were screened to calculate the detection level of polymorphism among them. For the SSRs present in the FONT SIZE=2 FACE="Symbol"g-gliadin locus, five different alleles were detected. One of the alleles was null, probably because of the absence of the microsatellite in the rye genome present in the varieties carrying the 1RS-1BS translocation. For the LMW-glutenin locus, eight different alleles were detected. All of the alleles behaved as codominant markers and, in contrast to RFLP markers, distinguished between homeoloci. The polymorphism information content (PIC) calculated showed the following values: PIC (LMW-glutenin) = 0.70 and PIC (FONT SIZE=2 FACE="Symbol"g-gliadin) = 0.74. These values are much higher than RFLP PIC values, which had a mean value of 0.41 for the Glu1-1A, Glu1-1B, and Glu1-1D RFLP markers. These high PIC values allow a finer characterization of the genetic variability present in the germplasm bank. In addition, the SSRs were more reproducible PCRs than RAPD markers, probably because of their higher annealing temperatures.

Reference.

Devos KM, Bryan GJ, Collins AJ, Stephenson P, and Gale MD. 1995. Application of two microsatellite sequences in wheat storage proteins as molecular markers. Theor Appl Genet 90(2):247-253.

Association between RFLP and SSR markers and bread-making quality parameters in Argentine wheats.

M.M. Manifesto, B.E. Tanos, S. Feingold, M. Echaide, H.E. Hopp, and J. Dubcovsky.

`Klein 32' (an Argentine variety from 1932) displays a HMW-glutenin SDS gel electrophoresis pattern identical to that of `Chinese Spring'. However, it shows significant differerences in SDS-sedimentation tests, which obviously is not explained by differences in HMW-glutenin patterns. Analysis of Klein 32 substitution lines allowed the location of breadmaking determinants on chromosomes 1B and 1D. A segregating F2 population was generated from the cross `Klein 32/Chinese Spring'. This population was used to correlate RFLP loci and SDS-sedimentation values. After testing the F2-derived descendents (F3), we found a significant correlation (p < 0.05) with RFLP and SSR (microsatellite) markers belonging to genes Gli1-B and Glu3-B (located on chromosome 1BS), indicating that this locus is responsible for about 7 % of the detected variation.


GENETICS INSTITUTE `E.A. FAVRET' - CICA - INTA

1712 Castelar, Buenos Aries, Argentina.

Isolation of a wheat mutant that simulates a hypersensitive-like phenotype in the absence of pathogens.

Alberto Acevedo.

A mutagenic treatment was applied to the Argentine bread wheat (T. aestivum L.) cultivar Sinvalocho M.A. Seeds were soaked overnight in an ethylmethane sulphonate (EMS, 2 %) solution and planted in the field. Four spikes/M1 plant were harvested individually and planted separately. M2 plants exhibiting a hypersensitive-like phenotype on spikes, leaf blades, and sheaths were detected in the progeny of one out of four spikes from an M1 plant. Progeny tests using the mutant, both as a female or male parent, revealed a 3:1 ratio, indicating a monogenic recessive character.

To further examine the expression of the mutated character, mutant and motherline plants were grown in the greenhouse in the absence of pathogens. As opposed to the motherline, the mutant exhibited the hypersensitive-like phenotype. This characteristic was not evident until the fifth leaf had emerged.

Root-tip mitotic analyses performed in the mutant and its motherline demonstrated that they were euploid plants (2n = 42) with no obvious chromosome abnormality. Electrophoretic analyses of storage proteins (gliadins and glutenins) in the mutant corresponded to the patterns of Sinvalocho M.A.


CÓRDOBA NATIONAL UNIVERSITY

College of Agriculture, P.O. Box 509, 5000 Córdoba, Argentina.

Wheat yield during a drought.

R. Maich, P. Daher, and M. Bianchi.

During 1995, the Córdoba province suffered the worst drought in history. A water deficit, accumulated from the previous spring season, magnified the drought. Rarely are results during a drought published or communicated. Two trials were sown at two locations in Córdoba (Oliva and Villa Maria). Twelve lines, nine experimentals and three commercials, were evaluated using plots of 24 560-m rows spaced 15 cm apart (2,240 sq m). Lines yielded from 100 kg/ha to 400 kg/ha. The experimental lines performed better than the commercials, from 43 % (Villa Maria) to 98 % (Oliva).

In situ vs ex situ plant breeding in the Argentine semiarid region.

M. Bianchi, P. Daher, and R. Maich.

The objective of this study was to determine the grain yield performance of experimental lines from our College and commercial cultivars developed outside, in the central, semiarid region of Argentina. Over two contrasting years (1994 and 1995) in the same location (Oliva) and in two different locations (Oliva and Costasacate) during 1994, the materials were evaluated using demonstration plots (2,240 sq m). Differences in lines in both trials were not significant. A descriptive analysis of the results shows that the grain yield mean performance of the experimental lines was the inverse of that of the commercial varieties in contrasting environmental conditions of cultivation. The crossover point between experimental and commercial lines is between 1,000 and 1,500 kg/ha. At the high end of this range of production, the commercial lines yielded more than the experimentals. However, at the low end, the experimentals performed better. With a regional average yield of 1,500 kg/ha, both types of lines are suitable for the central semiarid region of Argentina.

Indirect and direct selection criteria for grain yield in wheat.

A. Ordo-ez.

The objective of the present work was to measure the response to direct and indirect selection for grain yield using biological yield (BY), earweight (EW), and harvest index (HI) as indirect selection criteria and grain yield (GY) per se. In 1992, S1 plants of wheat (T. aestivum L.) from two crosses with different biological cycles were measured for BY, EW, HI, and GY. Two groups of 10 plants (superior and inferior) for each selection criterion were constituted using a disruptive selection intensity of 2.8 %. During 1993, at two sowing dates (May and June), the 160 S1:2 progenies were evaluated and grain yield was determined. An analysis of variance was performed on the superior groups corresponding to BY, EW, HI, and GY selection criteria. Simultaneously, superior and inferior mean groups were contrasted using the Student t-test. Direct selection was more efficient than harvest index as an indirect selection for grain yield. Differences among superior and inferior mean groups selected for BY, EW, and HI were not significant. The groups differed significantly only for direct selection.

Changes in ear characteristics related to three cycles of recurrent selection.

M. Bianchi.

A total of 30 families, 15 for each one of the two cycles analyzed (C0 and C3), were evaluated in order to determine the effect of three cycles of recurrent selection for grain yield on spike length, number of spikelets, kernels per spike, and kernel weight. Only the mean differences for spike length were significant. Families with the highest level of microevolution (3rd cycle) had longer spikes (7.6 cm) than those belonging to the base population (6.8 cm).

Flag leaf studies in bread wheat lines improved through a recurrent selection scheme.

P. Gil and A. Pascualides.

The objective of this research was to study three cycles of recurrent selection for grain yield in bread wheat and the influence on some associated biological aspects. Morphology of the flag leaf, the main vegetative organ that contributes to grain filling, was taken as a representative character. We worked with five flag leaves for each family of the 15 per cycle (C0 and C3)analyzed. Among the flag leaf characters analyzed, a significant increase from C0 to C3 cycle was observed only for leaf width.

Associated characters with competitive ability in wheat.

M. Zaninetti.

Four characters related to competitive ability in 30 wheat families, were recorded for 15 plants/family for each of the two cycles studied (C0 and C3). The following traits were analyzed for each plant: a) height, b) number of total tillers, c) number of tillers with ears, and d) the ratio of c to b (number of tillers with ears : number of total tillers). For the characters studied, only the c:b showed a significant difference between family means. The C0 families were 9.2 % more efficient than those of the C3. Material of the C3 is known to have the highest capacity to produce tillers. However, this tendency did not give more tillers with spikes. The low performance of C3 families with respect to the c:b could have been due to the drought that occurred in 1995.

Electrical conductivity in wheat seeds.

I. Arguello.

The objective of this study will be to measure seed vigor by a quick and simple method in order to determine variation between different cycles of a recurrent selection program in our College. Ten families from each cycle (C0, C1, C2, and C3) will be analyzed. The electrical conductivity will be measured on the basis of 25 seeds/family.

Molecular markers.

L. Torres.

Genetic factors affecting economically important traits such as grain yield are mediated through various biochemical or physiological processes in populations subjected to selection pressures. Concomitant changes would be expected in intermediary biochemical traits. Remnant seeds from successive selection cycles can be stored and used later to monitor any such changes. The frequency of changes in alleles at several enzyme (allozyme) loci will be monitored in wheat populations obtained through several cycles of selection. Seedlings from each one of the cycles of selection will be analyzed by electrophoretic assays for several allozyme loci. Regression analysis will be performed between cycles to measure allellic frequency.

Stomatal size variation of the epidermal flag leaf blade in bread wheat varieties.

S.P. Gil, A.L. Pascualides, and M.M. Cerana.

An analysis of the stomatal size was made in two commercial varieties (Las Rosas INTA and PROINTA Oasis) and in two experimental ones (T7 and T24) in relation to grain yield. The varieties were sown early in the season at two different row distances (15 and 30 cm) in plots of `11 m x 45 m'. Our work showed that stomatal length gave significant differences in the abaxial surface (P > 0.0147) and between varieties (P > 0.0021). The `variety x distance' interaction was not significant (P > 0.005). The stomatal length was greater in the 15 cm spaced rows, in agreement with the higher grain yield obtained from these rows. No differences were found between T24 and the commercial varieties. The stomatal width was not changed significantly.

Introduction as a possibility for obtaining qualitatively superior wheats.

Z.A. Gaido, G.A. Manera, and M.E. Dubois.

The quality of Argentine wheats has been in doubt. The market attempts to improve their quality by improving cultural practices or by developing qualitatively superior wheats. The objective of this work was to evaluate the grain yield and quality of wheat lines from CIMMYT, national varieties, and local experimental lines to determine the necessity of using introducted materials at the ground level of our breedings programs. Thirteen national varieties and 26 experimental lines (13 local and 13 from CIMMYT), adapted for the semiarid regions, were sown in the field at Ferreyra, Argentina (31_ 30' lat. S and 64_ 20' long. N), in 1994. The CIMMYT lines are useful because of their high protein content, whereas the local lines presented higher protein yields. The CIMMYT lines should be used as sources of genetic variability for increasing the protein content of materials developed for areas when needed.

Evaluation of a breadmaking test for wheat (T. aestivum L.).

G.A. Manera, M.E. Dubois, and Z.A. Gaido.

Advanced lines of wheat adapted for the semiarid region of central Argentina were baked experimentally in order to evaluate their industrial performance. The breadmaking test indicated the result of the interaction of the individual quality factors. Ten F5 lines of wheat, obtained in a wheat breeding program in the College of Agriculture, were selected in the F4 for agronomic yield, total protein content, dry and wet gluten, alveogram, and farinogram. The lines were baked using the official method of an experimental breadmaking test modified in the laboratories of Marcos Juarez at the Experimental Station of I.N.T.A. All lines gave bread that was satisfactory in volume, crumb color, and texture. In general, eight lines rated MB (very high quality) and two lines were BMB (promissory quality). The excellent results obtained in the breadbaking test confirmed the industial, high-quality index traits that the lines showed in the F4, such as total protein content, gluten content, flour strength, and dough developing time and stability. Short dough, indicated by alveographic values of a P/L > 1, did not have an influence on the results of the breadmaking test.

The influence of sowing rate on grain yield and breadmaking quality in commercial wheat cultivars.

M.E. Dubois, Z.A. Gaido, and G.A. Manera.

The new, commercial rules for bread wheat require improvement of the genetic potential for protein percent, in order to fix the bonifications and discounts that depend on grain protein content. The objective of this work was to analyze the influence of sowing date on grain yield, protein, and breadmaking quality in the commercial wheat cultivars of the V North Argentine wheat region. Eight wheat varieties and one wheat hybrid (all intermediate cycle) were sown in the field in 1993 and 1994. In both years, the first sowing date was superior to the second, with the protein percentage higher (in 1993) and equal (in 1994) to that of the commercial bread wheats. In highly fertile soils with adequate moisture, the protein content was maintained, but when fertility was lower and moisture limiting, it decreased at the second sowing date.

Publications.

Maich R, Daher P, and Bianchi M. 1995. Globalizacion de la produccion triguera: Productor, Tecnico y Empresario. Gac Agr XV 85:171-174.

Manera G. and Maich R. 1995. Trigos hibridos: Pasado, Presente y Futuro en Argentina. Gac Agr XV 86:270-274.