Phytic acid (myo‐inositol hexakisphosphate), the major storage form of P in seeds, is believed to have a negative impact on nutritional quality. Since breeding for low phytic acid has been proposed for several cereals and legumes, it is important to predict the effects of selection against phytic acid on other major grain components. Experiments were conducted to determine the quantitative relationship between grain phytic acid P, total P, and protein in two winter wheat (Triticum aestivum L.) populations, each consisting of F6 progeny of a double cross. Substantial variation in phytic acid P was observed, with the range in values equal to 30 and 48% of the respective population mean. Observed variation in phytic acid P was highly and positively correlated with variation in grain total P (r 0.93 and 0.96 in Populations 1 and 2, respectively), and with variation in grain protein (r = 0.65 and 0.87, respectively). The dose correlation of phytic acid P with both total P and protein indicates that selection against grain phytic acid would lead to undesirable reductions in both grain total P and protein.

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Plant growth, development, and yield of current tomato cultivars are directly affected by low temperatures. Although wild tomato species have been suggested as a potential source for low temperature tolerance, very little is known about their behavior during the reproductive phase. Here, we investigated the impact of suboptimal temperatures (SOT, 16/14°C), as compared to control temperatures (CT, 22/20°C), on plant growth, photosynthetic capacity, and carbohydrate metabolism. Under these conditions, two genotypes were analyzed: a Solanum lycopersicum cultivar Moneymaker and a high-altitude wild species Solanum arcanum LA385, from flowering onset until a later stage of fruit development. Total dry matter production in cv. Moneymaker was reduced up to 30% at SOT, whereas it was hardly affected in wild accession LA385. Specific leaf area, total leaf area, and number of fruits were also decreased at SOT in cv. Moneymaker. In contrast, wild accession LA385 showed an acclimation to SOT, in which ΦPSII and net CO2 assimilation rates were less affected; a similar specific leaf area; higher total leaf area; and higher number of fruits compared to those at CT. In addition, LA385 appeared to have a more distinct sucrose metabolism than cv. Moneymaker at both temperatures, in which it had higher contents of sucrose-6-phosphate, sucrose, and ratio of sucrose: starch in leaves and higher ratio of sucrose: hexose in fruits. Overall, our findings indicate that wild accession LA385 is able to acclimate well to SOT during the reproductive phase, whereas growth and development of cv. Moneymaker is reduced at SOT.

Saponin content of alfalfa (Medicago sativa L.) was affected by variety, stage of growth, and percentage of leaves. Leaves were higher in saponin content than stems and immature growth was higher in saponin content than more mature growth. The ‘Du Puits’ variety was higher in saponin content than ‘Lahontan’ and this difference became greater as the growing season progressed. The varietal difference was reflected in the growth rate of chicks fed alfalfa meal differing in saponin content and in the growth rate of Trichoderma viride Pers. ex Fr. growing on water extracts of the varieties. Both qualitative and quantitative differences in alfalfa saponin are suggested by the Trichoderma bioassay. Saponins extracted from the varieties inhibited the germination of lettuce seed to different degrees. This was attributed to qualitative differences in the saponins from the different varieties. Improvement of the feeding value of alfalfa by breeding for low saponin content is an attractive possibility.

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