The European corn borer, Ostrinia nubilalis (Hübner), is devastating insect pest in the corn (Zea mays L.) growing regions of North America and Europe. Field evaluations in the USA and Belgium showed that transgenic corn events expressing Cry9C, an insecticidal crystal protein from Bacillus thuringiensis subsp, tolworthi, very effectively control both generations of the European corn borer. Second to fourth instar larvae fed with leaf material of event CBH351 expressing the Cry9C protein all died within 4 d. Cry9C events, expressing high levels of the insecticidal protein, showed minimal stalk tunneling after heavy artificial infestations. Event CBH351 tested in plots containing only Cry9C transgenic plants had 0.14‐ and 0.09‐cm tunneling per stalk compared with more than 30‐ and 23‐cm tunneling per stalk for the negative controls, in the Belgium and Iowa field trial, respectively. In plots containing 30% non‐transgenic plants the event CBH351, showed only 1.45‐cm tunneling per stalk. Leaf, tassel, and pith tissue contained 39.0, 17.4, and 84.8 μg Cry9C protein mg−1 soluble protein, respectively, in analyses conducted at harvest of the Belgium trial. The implications of Cry9C use for resistance management strategies are discussed.

Classification of homozygous opaque‐2 kernels of maize (Zea mays L.) in segregating progenies has been done on the assumption that the phenotype of these kernels is completely opaque. Certain lines in the S2 generation derived from opaque appearing S1 parents produced two phenotypic classes: (1) entirely opaque, and (2) modified opaque‐1/2 opaque : 1/2 translucent.Lysine content of 1/2 : 1/2 kernels was not different from opaque kernels on the same ear. Likewise the lysine content of translucent and opaque fractions of the endosperm from the 1/2 : 1/2 class was not different.High lysine corn with a high test weight and other desirable kernel characteristics may be produced by taking advantage of this opaque‐2 phenotypic expression.

Four corn types with different doses of mutant amylose-extender (ae) and floury-1 (fl1) alleles, in the endosperm, including no. 1, aeaeae; no. 2, fl1fl1fl1; no. 3, aeaefl1; and no. 4,fl1fl1ae, were developed for use in making Hispanic food products with high resistant starch (RS) content. The RS percentages in the native starch (NS) of 1−4 were 55.2, 1.1, 5.7, and 1.1%, respectively. All NS were evaluated for pasting properties with a rapid viscoanalyzer (RVA) and for thermal properties with a differential scanning calorimeter (DSC). NS 1 had a low peak viscosity (PV) caused by incomplete gelatinization, whereas NS 3 had the greatest PV and breakdown of all four starch types. On the DSC, NS 2 had the lowest onset temperature and greatest enthalpy. NS 1 and 3 had similar onset and peak temperatures, both higher than those of NS 2 and 4. The gel strength of NS heated with a RVA was evaluated by using a texture analyzer immediately after RVA heating (fresh, RVA-F) and after the gel had been stored at 4 °C for 10 days (retrograded, RVA-R). NS 1 gel was watery and had the lowest strength (30 g) among starch gel types. NS 3 gel, although exhibiting syneresis, had greater gel strength than NS 2 and 4. The structures of the NS, the RS isolated from the NS (RS-NS), the RS isolated from RVA-F (RS-RVA-F), and the RS isolated from RVA-R (RS-RVA-R) were evaluated by using size exclusion chromatography. NS 1 had a greater percentage of amylose (AM) (58.3%) than the other NS (20.4−26.8%). The RS from all NS types (RS-NS) had a lower percentage of amylopectin (AP) and a greater percentage of low molecular weight (MW) AM than was present in the original NS materials. The RS-RVA-R from all starches had no AP or high MW AM. The percentages of longer chain lengths (DP 35−60) of NS were greater in 1 and 3 than in 2 and 4, and the percentages of smaller chain lengths (DP 10−20) were greater in 2 and 4 than in 1 and 3. In general, NS 3 seemed to have inherited some pasting, thermal, and structural characteristics from both NS 1 and 2, but was distinctly different from 4. Four corn types with different doses of mutant amylose-extender (ae) and floury-1 (fl1) alleles, in the endosperm, including no. 1, aeaeae; no. 2, fl1fl1fl1; no. 3, aeaefl1; and no. 4, fl1fl1ae, were developed for use in making Hispanic food products with high resistant starch (RS) content. The RS percentages in the native starch (NS) of 1-4 were 55.2, 1.1, 5.7, and 1.1%, respectively. All NS were evaluated for pasting properties with a rapid viscoanalyzer (RVA) and for thermal properties with a differential scanning calorimeter (DSC). NS 1 had a low peak viscosity (PV) caused by incomplete gelatinization, whereas NS 3 had the greatest PV and breakdown of all four starch types. On the DSC, NS 2 had the lowest onset temperature and greatest enthalpy. NS 1 and 3 had similar onset and peak temperatures, both higher than those of NS 2 and 4. The gel strength of NS heated with a RVA was evaluated by using a texture analyzer immediately after RVA heating (fresh, R...

Whole kernel lysine content was determined on inbred lines and Plant Introduction strains of corn (Zea mays L.). The lysine values ranged from 0.16 to 0.45%. The largest values are comparable to whole kernel lysine contents of opaque‐2 mutants. The distribution was normal with a mean of 0.30% and a standard deviation of 0.04%. A significant correlation (r=0.48) was obtained between whole kernel lysine and protein for a selected group of high‐lysine lines. Little variability in lysine content was noted for six inbred lines grown at different stations in different years.

Inheritance of grain test weight in high‐amylose corn (Zea mays L.) was studied by measuring the test weight performance of several inbred lines crossed on two singlecross testers and by a diallel mating system. Wider ranges in test weight were obtained with the low test‐weight tester than with the higher test‐weight tester. Rankings of entries for test weight were (1) highly correlated between years, (2) intermediate between locations, and (3) low between testers. The diallel analysis indicated a preponderance of additive genetic effects. Single‐cross hybrids involving inbred parents with low test weights had lower test weights than hybrids from Low by High and High by High inbred parents, with the latter group having the highest test weights. Likewise, inbred parents with low test weights gave lower top cross test weight performance than inbreds with higher test weights. Low test‐weight single‐cross testers had lower average test weights than testers with higher test weights. Breeding methods which take advantage of the large additive effects should be suitable in improving test weight of high‐amylose corn