Biffen demonstrated that the baking quality of wheat was under genetic as well as environmental control. His variety Yeoman made a major contribution to food supplies in UK in the early twentieth century. The science and art of plant breeding for wheat quality in the twentieth century is reviewed, including the development of tests to provide information on baking quality.

White clover (Trifolium repens L.) and red clover (T. pratense L.) are the most important legumes of temperate pastures. The former is used largely in systems based around sheep or cattle grazing and is grown together with a companion grass. Breeding aims to optimize the white clover contribution to the sward. This means that yield per se is not the aim but rather to take full advantage of the benefits of white clover; in particular, nitrogen fixation, high protein content, digestibility, mineral content and high intake. The objective is an agronomically and, as far as possible, nutritionally balanced sward, thus persistence of white clover and yield stability over a number of years are key goals. A considerable focus of germplasm improvement has therefore been overcoming biotic and abiotic stresses to clover performance. The former include not only pests and diseases but also the impact of the ruminant animal and the competitive interaction with the companion grass, while abiotic stress could be loosely defined as ‘winter hardiness’ and ‘summer survival’ depending on the site. In recent years the focus of many breeding efforts has shifted to give more consideration to the effects of variation within white clover germplasm on animal performance and the environment. Beneficial effects on productivity have been known for many years, but recent studies of the impact of forage diets on meat and milk quality have opened up new opportunities for improvement. Diffuse pollution of nitrogen and phosphorus from agricultural sources is high on the environmental protection agenda of many governments. Breeding efforts are now being made to reduce the contribution of clovers to both direct (leaching) and indirect (through animal returns) pollution. In particular, recent insights into mechanisms affecting protein breakdown in the rumen and silo offer new prospects for breeding interventions to reduce environmental impacts.

Molecular marker methods are being developed in white clover and the transfer and use of resources and information accumulating in the model legumes Medicago truncatula and Lotus japonicus is likely to be a major route by which the power of genomic approaches is translated into forage legume improvement. Hybrids of white clover and related species have been developed to introgress key traits; namely, drought tolerance, grazing tolerance of large leaf types and enhanced seed yield, for which only limited genetic variation is present within the white clover gene pool.

Red clover is less persistent than white clover, is typically cut three or more times in a season and is used to make silage for winter feed. Although it is often grown with a companion grass, monocultures are common and yield per se as well as persistency and pest and disease resistance are major breeding aims. Fewer agronomic studies and less germplasm improvement have been carried out in this species and molecular studies are not as well advanced although, as with white clover, future developments are likely to benefit greatly from a close relationship to model legumes. Red clover brings considerable benefits in terms of animal production and meat and milk quality. These aspects, alongside approaches to reduce nitrogenous pollution from the silo, represent considerable opportunities for variety development.

Extensive research has been conducted on temperate cereal development since the inception of the Journal of Agricultural Science, Cambridge in 1905. This review presents an overview of the orderly and predictable development of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). It begins with the concept of building canopies by the formation, growth and senescence of phytomers (the unit comprised of the leaf, axillary bud, node and internode). Morphological naming schemes for uniquely identifying each plant part are then extended to uniquely name each phytomer unit. The role of the phyllochron (rate of leaf appearance) in synchronizing cereal development and phytomer formation is discussed, as is the use of phenology to predict the timing of the formation, growth and senescence of individual components. The complete developmental sequence of the winter wheat shoot apex correlated with growth stages is extended to spring barley. This overview discusses the abiotic factors controlling cereal development, with special attention given to key questions regarding the critical role of temperature. The review concludes with some cautious glances forward to the exciting possibilities for better understanding of mechanisms controlling the phyllochron and phenology being gained from advances in functional genomics and molecular biology.

The aim of the research was to describe and characterize the physiological basis of Mn use efficiency among a range of old and modern UK wheat cultivars grown in Mn-depleted solution culture and to ascertain whether the existence of Mn use efficiency conferred a yield advantage under manganese stress conditions in the field. Results of solution culture experiments demonstrated that the old spring wheat cv. Maris Butler is relatively Mn efficient when grown in Mn-deficient conditions in comparison with both a modern winter wheat, cv. Claire, and a modern spring wheat, cv. Paragon. The mean dry weight gain of plants of cv. Maris Butler grown in Mn-depleted nutrient solution was 0·49 of that shown by plants in Mn-sufficient culture, whereas in cvs. Paragon and Claire the equivalent values were 0·38 and 0·21 respectively. When grown in Mn-deficient soil in a farm-based field trial, cv. Maris Butler showed significantly improved (P<0·05) dry matter accumulation and grain yield compared with other spring wheats including cv. Paragon. There was no significant variation in leaf Mn content between the cultivars examined, either under sufficient or depleted Mn supply; however, cv. Maris Butler showed both a relatively high maximum light-saturated rate of photosynthesis and a high photosynthetic apparent quantum yield (based on O2 evolution) when grown under Mn deficiency. It is argued that the apparent Mn use efficiency of cv. Maris Butler is related to superior internal utilization of Mn, resulting in an increased photosynthetic photosytem II efficiency rather than improved Mn uptake and accumulation. The results suggest that the wheat cultivar Maris Butler may provide a potentially useful source of parental material for future crop improvement programmes designed to produce wheat lines resistant to depleted Mn supply.

Stomatal conductance plays an important role in the heat avoidance mechanism of crop plants. Stomatal conductance in cotton is genetically determined and has been shown to be associated with heat resistance and higher yields. Experiments were carried out with six generations (parental, F1, F2 and back crosses) of three upland cotton crosses under heat-stressed and non-stressed greenhouse and field regimes, to understand the inheritance pattern of stomatal conductance as affected by contrasting temperature regimes. The results revealed significant variation for stomatal conductance due to generations and generation×temperature regime interaction in the three crosses. In general, heat stress reduced stomatal conductance and available genetic variability. Temperature regimes exerted a significant effect on the expression of the genes responsible for stomatal conductance. High temperature or heat stress favoured the expression of genes having additive effects, while absence of heat stress favoured those having dominant effects in two of the three crosses evaluated. The third cross showed the opposite reaction. The results suggest that genes controlling stomatal conductance in the parents of the first two crosses (MNH-552, HR109-RT, CIM-448, CRIS-19) were different from those controlling stomatal conductance in FH-900 and N-Karishma, the parents of the third cross. The selection efficiency of stomatal conductance in segregating populations was likely to be affected by the complexity of its inheritance, environmental dependency, and presence of substantial non-allelic and genotype×temperature regime interactions.

A common method to describe maize phenology during the vegetative phase is to determine the number of leaves. The thermal interval between the appearance of successive leaves, called the phyllochron, is critical for predicting the duration of vegetative development. In general, there is a high correlation between the final number of initiated leaves and the duration from sowing to silking. The development of a crop depends on temperature and photoperiod and genetic response to these environmental factors, thus bio-meteorological indices are needed to describe this process. The goal of this study was to obtain a better understanding of the phyllochron and its impact on the final number of leaves. A second objective was to evaluate three thermal indices for predicting the duration of sowing to silking and silking to physiological maturity for four maize hybrids grown off-season in a subtropical region of the Southern Hemisphere (São Paulo State, Brazil). The modified general thermal index (mGTI) was compared with the classical thermal time concept (TT) with two sets of cardinal temperatures, including TT(10) with 10 °C as minimum base temperature (Tb) and TT(8) with 8 °C as Tb. Three field experiments that included four hybrids with different relative maturity ratings were conducted during the autumn and winter growing seasons of 2001 and 2002 at the University of São Paulo, in Piracicaba, SP, Brazil. Phenology was recorded daily. Also, an independent evaluation of three methods for estimating phenology was conducted with data obtained from the variety trials of the ‘Instituto Agronômico’ for four regions of the State of São Paulo, Brazil. The results indicated that the value for the phyllochron was about 50 °Cd/leaf until approximately the appearance of the 12th leaf, and then declined. For estimating the planting to silking period, the TT(10) method resulted in a coefficient of variation (CV) of 2·01%, while for TT(8) the CV was 1·37% and for mGTI the CV was 1·04%. For the period from silking to physiological maturity, the CV was 2·91% for the TT(10), 2·64% for the TT(8) and 2·01% for the mGTI method. All CVs were very small, suggesting that there was only a slight difference between algorithms. It can be concluded from this study that the mGTI can be used for estimating both silking and physiological maturity dates for maize grown off-season in subtropical regions of Brazil because it resulted in the smallest CV. However, additional studies with different maize hybrids are necessary to confirm the advances in estimating the main phenological phases for maize based on the mGTI.

A non-destructive indicator of seed water content could significantly help crop scientists with assessment of the effects of environmental conditions during drying on grain qualities or on seed physiological quality. This is particularly important for grain legumes which simultaneously bear pods of different ages. Visual assessment of pod colour has so far been used to date grain legume stages, but now colour can be easily and accurately measured with a portable spectrophotometer. Relationships between the spectrophotometer measurements and the pod and seed water contents were tested in various climatic contexts (3 years: 2000, 2001, 2002; field or greenhouse, two or three sowing dates) for two bean cultivars (Booster and Calypso) and also for one pea cultivar (Baccara) in 2003 near Angers, France. Among the different spectrophotometer measurements, hue angle (h) clearly shows the transition from green (h=180 °) to yellow (h=90 °) and then to red (h=0 °). In each context, h and seed water content (SWC) relationships showed the same pattern of three linear phases: first a steady state; then a sharp decrease from green (h=106–108 °) to yellow (h=85–93 °) just before the end of the seed filling stage for Booster or between the end of the seed filling phase and the beginning of seed drying for Calypso and pea; finally, a slow decrease from yellow to ochre (h=75–78 °) during seed drying. For each bean cultivar, the parameters of the linear relationships showed no differences between maturation conditions. Therefore, 6 h classes matching six SWC classes could be defined over a wide range of SWC between 0·56 and 0·2 g/g for Booster. However for Calypso and pea, only 3 h classes could be defined because of the tight relationships between h and SWC during the end of seed drying, which can be explained by pod walls drying faster than seeds. Hence, spectrophotometer measurements, if calibrated for a given cultivar of a species, could now be used to select pods with seeds of the same water content and therefore to study environmental effects on quality criteria either in controlled conditions or in the field.

To clarify the reproduction probability of red clover (Trifolium pratense L.) in meadows for herbage cutting, the demography of this legume was studied in a meadow in the central mountainous district of Japan. The present study shows the demography of deposited red clover seeds in a meadow, where timothy (Phleum pratense L.) predominated and herbage had been harvested for making hay or silage in early June and late August of a year. The densities of deposited seeds, buried seeds and seedlings were monitored to determine their survival. Deposited seeds were collected using seed traps, buried seeds were monitored seasonally by sampling them from topsoil and seedlings were counted in ten permanent 1×1 m quadrats. Many permeable and hard seeds of red clover were deposited on the soil surface of the meadow during the mechanical operation of the second haymaking in mid- to late August. Of the population of deposited permeable seeds, 0·16 germinated and 0·84 were lost in the present autumn. Conversely, of the population of deposited hard seeds, 0·11 germinated in the succeeding spring, 0·83 were lost and 0·06 remained as hard seeds until the succeeding autumn. The deposited permeable and hard seeds could contribute to the persistence of red clover population when their seedlings survived for seed setting in the meadow.

Brody, Gompertz, Logistic, Richards and von Bertalanffy functions were compared as descriptors of growth in 319 coypus (Myocastor coypus) of Greenland and Silver varieties, from birth to 10–19 months of age. Several criteria were considered for the selection of the model: (a) bias in the asymptotic weight; (b) bias in birth weight; (c) error sum of squares; (d) error mean squares weighted by the number of animals converging in all functions; (e) determination coefficient. To adjust the curves NLIN procedure from SAS and iterative method of Marquardt were applied. A mixed model was used to analyse the parameters of the selected growth curve (asymptotic weight, A; constant of integration, B; and maturation rate, k) which included effects of farm, variety, sex, sire within farm and variety, reproductive status within sex, birth season and first order interactions. The effect of sire was considered as random. The von Bertalanffy function was selected and mean values for the parameters of this function were 8016 g and 0·008 g/g per day, for A and k respectively. There were differences in the estimated parameters between sexes; males had larger values of A and k than females.

Weights at fixed ages (birth, weaning, 6–7 months) were analysed, as well as the final recorded weight and average postweaning gain. The model of analysis was similar to the previous one. There were no differences between varieties. Significant differences between sexes for almost all studied traits were detected. With age, weight difference between males and females increased. At 6 months of age, males were 37% heavier than females. Male average daily gain was higher than that of females, sexual dimorphism being evident in all analysed traits.

The active germplasm Bank of the Integrated Unit (Facultad de Ciencias Agrarias, Unversidad Nacional de Mar del Plata and the Experimental Station of INTA) at Balcarce, keeps both in vivo (live herd) and in vitro Criollo Cattle (samples of semen and embryos cryogenically), with the aim of preserving genetic variability for potential future use. Parameters based on probable origin of genes, on population size and on the estimation of components of (co)variances for birth and weaning weights were estimated to evaluate the genetic variability of the material contained in the Bank. The information available came from 667 individuals, of which 84 had unknown parents, and 142 half-founders (only one parent known), having a mean number of births per year of 24 calves from four different sires. AI was performed during the mating season almost every year. The evolution of effective number of founders (fe), effective number of ancestors (fa), effective number of founder genomes (Ng) and the ratio fe/fa over different periods from the creation of the Bank, were analysed. Annual increase of inbreeding coefficient (F) was 0·2% and the effective population size (Ne) was estimated as 23, 14 and 25 individuals for the periods defined by years 1978–82, 1983–87 and 1993–97, respectively. The ratio fe/fa was higher in the years where the ratio number of sires/number of dams was lower, indicating that the impact of the effective number of sires is more important than the effective number of females in generating genetic bottlenecks. When the reference population was taken for the period 1989–97, 16·45 out of the 85·63 founders of the population made contributions not explained by other ancestors, but if possible losses of genomes due to genetic drift are considered, the number of genomes still present was reduced to 9·09 indicating a possible narrow genetic bottleneck in the last period. The Ng/fe ratio was 0·11, 0·10 and 0·11 for the reference populations defined by years 1989–92, 1993–97 and 1989–97, respectively. The main objective in germplasm conservation programmes should be the maintenance of genetic variability. Thus, matings in the population under conservation should be designed in order to mate those animals that maximize the effective number of genome founders (Ng) to avoid losses due to genetic drift.

A model of sugarcane digestion was applied to indicate the suitability of various locally available supplements for enhancing milk production of Indian crossbred dairy cattle. Milk production was calculated according to simulated energy, lipogenic, glucogenic and aminogenic substrate availability. The model identified the most limiting substrate for milk production from different sugarcane-based diets. For sugarcane tops/urea fed alone, milk production was most limited by amino acid followed by long chain fatty acid availability. Among the protein-rich oil cake supplements at 100, 200 and 300 g supplement/kg total DM, cottonseed oil cake proved superior with a milk yield of 5·5, 7·3 and 8·3 kg/day, respectively. This was followed by mustard oil cake with 5·1, 6·5 and 7·6 kg/day, respectively. In the case of a protein-rich supplement (fish meal), milk yield was limited to 6·6 kg/day due to a shortage of long chain fatty acids. However, at 300 g of supplementation, energy became limiting, with a milk yield of 6·7 kg/day. Supplementation with rice bran and rice polishings at 100, 200 and 300 g restricted milk yield to 4·3, 4·9 and 5·5 and 4·5, 5·3 and 6·1 kg/day, respectively, and amino acids became the factor limiting milk production. The diet comprising basal sugarcane tops supplemented by leguminous fodder, dry fodder (e.g. rice or wheat straw) and concentrates at levels of 100, 200 and 300 g supplements/kg total diet DM proved to be the most balanced with a milk yield of 5·1, 6·7 and 9·0 kg/day, respectively.