Soybean [Glycine max (L.) Merr.] is one of the most important crops in the world. It is a major source of vegetable oil for consumption and protein meal for animal feeds and has also been widely used in human food industries because of its nutritive and health benefits. To provide useful information for soybean quality improvement, seed individual sugars, total sugar, protein, oil, and dietary fiber were genetically analyzed in replicated trials with 323 germplasm lines grown in South Dakota and 137 cultivars and breeding lines grown in Virginia. The results indicated significant differences among the genotypes for all traits investigated. Environment effect and genotype × environment interaction were also significant in most cases. Heritability estimates were high (94.45–97.79%) for all traits in the germplasm population, and higher in the population of breeding lines for most traits. High genotypic correlation existed between sucrose and total sugar, which helps improvement of digestible sugars and sweetness in soybean food. However, attention should be paid to the lines with higher sucrose but lower oligosaccharides, since stachyose was positively associated with total sugar. Genotypic correlations between seed sugars and protein were insignificant or very low in most cases, implying that alteration of seed sugars might not necessarily affect protein. In some cases, however, there might be negative correlations between seed sugars and oil or dietary fiber in soybean. This study also identified some unique germplasm lines with a desired level of a specific seed composition: one with high sucrose, five with low raffinose, 15 with high total sugar, seven with high protein, and four high in both sucrose and total sugar.

The influence of temperature, irradiance, photoperiod and growth retardants on growth and flowering of Angelonia angustifolia Angel Mist series was evaluated. When temperature was increased from 15 to 30 °C, time to visible bud and time to flower decreased in a quadratic manner but total plant height and flower stem dry weight increased linearly. As irradiance increased, time to flower, time to visible bud, and height decreased quadratically. Changes in photoperiod had no effect on growth or flowering, suggesting that A. angustifolia is a day-neutral species with regards to height and flowering time. Daminozide, ancymidol, and paclobutrazol resulted in significant reduction of plant height compared with control plants but did not influence flowering time. Chemical names used: K-cyclopropyl-K-(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol); butanedioic acid mono (2,2-dimethylhydrazide) (daminozide); K-[(4-chlorophenyl)methyl]-K-(1,1-dimethyethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol).

Light and temperature responses of whole-plant CO2 exchange were determined for two cultivars of Angelonia angustifolia Benth., `AngelMist Purple Stripe' and `AngelMist Deep Plum'. Whole crop net photosynthesis (Pnet) of `AngelMist Purple Stripe' and `AngelMist Deep Plum' were measured at eight temperatures, ranging from 17 to 42 °C. Pnet for both cultivars increased from 17 to ≈20 °C, and then decreased as temperature increased further. Optimal temperatures for Pnet of `AngelMist Purple Stripe' and `AngelMist Deep Plum' were 20.8 and 19.8 °C, respectively. There was no significant difference between the two cultivars, irrespective of temperature. The Q10 (the relative increase with a 10 °C increase in temperature) for Pnet of both cultivars decreased over the entire temperature range. Dark respiration (Rdark) of both cultivars showed a similar linear increase as temperature increased. As photosynthetic photon flux (PPF) increased from 0 to 600 μmol·m-2·s-1, Pnet of both cultivars increased. Light saturation was not yet reached at 600 μmol·m-2·s-1. The light compensation point occurred at 69 μmol·m-2·s-1 for `AngelMist Purple Stripe' and at 89 μmol·m-2·s-1 for `AngelMist Deep Plum'. The lower light saturation point of `AngelMist Purple Stripe' was the result of a higher quantum yield (0.037 mol·mol-1 for `AngelMist Purple Stripe' and 0.026 mol·mol-1 for `AngelMist Deep Plum'). The difference in quantum yield between the two cultivars may explain the faster growth habit of `AngelMist Purple Stripe'.

The following theorem is proved: A knight's tour exists on all  chessboards with one square removed unless: n is even, the removed square is (i, j) with i + j odd, n = 3 when any square other than the center square is removed, n = 5, n = 7 when any square other than square (2, 2) or (2, 6) is removed, n = 9 when square (1, 3), (3, 3), (1, 7), (3, 7), (2, 4), (2, 6), (2, 2), or (2, 8) is removed, or when square (1, 3), (2, 4), (3, 3), (1, n-2), (2, n-3), or (3, n-2) is removed.

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