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A study of a collection of 903 varieties of safflower (Carthamus tinctoriusL.) for the mean yield per plant and the three major yield components, number of heads per plant, number of seeds per head, and seed weight, revealed marked differences in the potential of lines from different origins. Because of the mutual compensation of the yield components, the differences in yield were not as marked as they were for the components. The collection contains an abundance of genetic variability which is available for breeding higher‐yielding safflower varieties. There were regional differences in the components due to human and/or natural selection. A multiple stepwise regression analysis showed that the most important yield component was the number of heads per plant. The number of seeds per head was of little importance, except for lines from Iran. Seed weight had no effect on yield per plant, except for a minor influence in the Iranian lines. The number of heads per plant had negative but negligible correlations with oil content. Yield per plant was not correlated with season length or oil content. Since the findings were obtained under spaced nursery conditions, they are not necessarily applicable directly to dense field stands.

Performance of the F1, F2and backcross generations of nine interspecific crosses, between each of three varieties of Gossypium hirsutumL. (‘Acala 4‐42’, ‘Empire W,’ and ‘Coker 100A’) and each of three varieties of G. barbadenseL. (‘Karnak,’ ‘Malaki,’ and ‘Giza 7’), in comparison with the parental varieties, was evaluated in three field trials in 1964 and 1965. Heterosis (F1performance above mean of parents) was between 52% and 73% for lint yield and was associated with heterosis for boll number, flower number, and percentage of boll retention. Boll weight of F1hybrids was intermediate and their lint percent and number of seeds per boll were lower than the parental mean. Heterosis was also significant for seed index, lint index and plant height. F2deviation (F2performance below mean of F1and midparent) and backcross deviations (BC performance below mean of F1and recurrent parent) were significant for almost all of the characters examined. Lint yield of the F2was much lower than that of either parent, whereas lint yield of backcrosses was similar to that of the recurrent parents. Heterosis was caused by dominance effects only (no epistasis) for seed index and in one trial for final plant height. Heterosis for yield of seed cotton, yield of lint, boll number, flower number, percentage of boll retention, lint index and plant height at flowering was caused by dominance in the presence of epistasis. Intermediate F1performance (no heterosis), found for boll weight and for maturity, was caused by the estimates of dominance and additive ✕ additive epistasis parameters being of nearly equal magnitudes. The negative heterosis found for lint percent and number of seeds per boll was caused by the additive ✕ additive epistasis being larger than the dominance effects.

In interspecific crosses between varieties of upland (Gossypium hirsutumL.) and Egyptian (G. barbadenseL.) cotton, tested in Israel from 1959 through 1965, F1performance for upper‐half‐mean and mean lint length exceeded that of either parent by 10 to 16% and 6 to 13%, respectively. The uniformity ratio of F1plants was slightly lower than the parental mean. F2performance for lint length was slightly above parental mean, but a significant F2deviation was detected for this trait. There were indications that additive, dominance, and additive ✕ additive epistatic effects were operating in the inheritance of lint length. The tensile strength (1/8‐in. gauge, i.e. T1of the F1's lint was almost as high as that of the stronger G. barbadenseparental varieties. The magnitude of heterosis was 9 to 15% for this trait, with no F2or backcross deviations. This indicated that only additive and dominance effects were operating in the inheritance of lint strength. Micronaire measurement of lint fineness was much lower in F1hybrids than in either parent (a negative heterosis of 12 to 19%). Only the dominance effects were detected as operating significantly in the inheritance of this trait, but there were considerable deviations from the model with no epistasis. Significant effects of general combining ability were found for lint length and tensile strength. Additive gene‐action was predominant for these traits. Dominance effects were the main cause of heterosis for all the traits of lint quality examined.

The effect of three irrigation treatments on the vegetative development of two cultivars of upland cotton (Gossypium hirsutumL.) was studied in two experiments conducted under different climatic conditions. The treatments differed until the middle of flowering and were designated as L (no irrigation), M (regular), and H (early and excessive irrigation). From mid‐flowering onwards all plots were irrigated regularly. In both experiments, treatment L resulted in a slower growth rate, smaller plants, fewer nodes and fruiting branches, and smaller leaf area index (LAI), and dry matter (DM) weight throughout the season. Small differences were found between the effects of treatments M and H. No excessive vegetative development was observed in this study. The highest rates of DM production were associated with LAI values between 2.0 and 3.0. A close relationship was found between, lint yield, DM production and leaf area duration (LAD). Only small increases in lint yield were associated with LAD and DM exceeding values of 100 days and 600 g/m2, respectively, at the end of the main flowering period. Smaller values of LAD and DM, however, were associated with reduced lint yield. Vegetative development was slower under the high temperatures prevailing in the Bet‐She'an valley than in the Coastal Plain area. Lint yield produced from the first cycle of flowering was lower in Bet‐She'an than in the Coastal Plain, but additional yields were produced in Bet‐She'an from the second cycle of flowering.

Trials were conducted in 1961 and 1962 on seven and eight varieties, respectively, of G. hirsutumL. and G. barbadenseL. and all possible reciprocal crosses between them. The average magnitude of heterosis for lint yield was 24.5% and 21.6% in the intraspecific crosses of G. OirsutumL. and G. barbadenseL., respectively, and 72.8% in the interspecific crosses. Heterosis for lint yield was associated in all cases with heterosis for yield of seedcottou and in many cases also for the number of bolls per m2. Heterosis for boll‐weight was found only in G. hirsutumL. intraspecific crosses where it was associated with heterosis for seed‐index, lint‐index, and number of seeds per boll. The interspecific crosses had a low lintpercent because heterosis for seed‐index was much more pronounced than heterosis for lint‐index in these crosses. Effects of general combining ability in the interspecific crosses, which were more pronounced than effects of specific combining ability, corresponded to the performance of the parental varieties themselves. If heterosis in interspecific crosses is to be used to breed F1 hybrids, the selection of parental varieties should be made on the basis of their own performance for those traits that have shown consistent and significant effects of general combining ability.

Nine varieties of oriental tobacco and all possible F1hybrids among them were evaluated at two locations in srael. Yield of cured leaves, mean weight per cured leaf, number of leaves per plant, plant height, combustibility, total alkaloid content, and days to flowering were determined. The average yield of cured leaves of the hybrids was 21% above that of the parental varieties. Other traits with the exception of combustibility and total alkaloid content exhibited significant heterotic effects. The magnitude of heterosis was similar at both locations. The ranking of the varieties according to their relative general combining ability was similar, in most cases, to their ranking according to parental performance. It was suggested that additive genetic variance was predominant for all the traits that were examined, but there was an indication that nonadditive components of genetic variance may also be present. We concluded that the procedure of selecting homozygous lines from the segregating progeny of a cross would be more suitable than using first‐generation hybrid varieties for breeding oriental tobacco.

A single irrigation, applied at the beginning of flowering, improved the lint yield of cotton by increasing boll size and number of bolls. An earlier or later irrigation, applied at the initiation of flower‐bud formation or at the peak of flowering, was less effective. The later irrigation, however, resulted in bigger bolls and longer and more mature lint.

The performance of interspecific and intraspecific F1hybrids of Gossypium hirsutumand G. barbadenseplanted on two different dates was investigated. The interspecific crosses showed significant heterosis for percentage and time of germination, leaf number, and date of square formation when planted on the first planting date, and for plant height, LAI, and dry matter weight for both planting dates. The G. barbadenseintraspecific cross exhibited a higher degree of heterosis than the G. hirsutumone for germination and dry matter weight when planted on the first planting date. The traits exhibiting significant estimates of heterosis for early planting, but not for late planting, were those associated with the early phases of plant growth. The differences stemming from planting dates were probably due to the low temperature that prevailed after the first planting, since the temperature after the second planting was close to the optimum. We concluded that F1hybrids have greater phenotypic stability than their parents when confronted with varying temperature conditions. This condition probably results from their heterosis for seedling growth rate under suboptimal temperature regimes.

Six experiments were conducted at four locations in Israel in order to evaluate the effect of two growth retarding chemicals, CCC and CMH, on plants of Upland cotton, Gossypium hirsutumL. When sprayed during the first week of flowering, CCC at 50 and CMH at 480 g a.i./ha retarded the increase in height of cotton plants without adversely affecting lint yield or quality. These treatments caused a small reduction in flower production, but this was not associated with a decrease in yield. In some of the experiments, the increase in plant height following treatment was reduced by as much as 50%. Application of CCC at the rate of 100 g a.i./h at the beginning of flowering significantly reduced lint yield in one experiment. Increasing the rate of CMH to 720 g a.i./ha produced no harmful effects. When CCC or CMH were applied in the middle of the flowering period, they were less effective in reducing plant height. These results indicate that both CCC and CMH may be used to arrest excessive vegetative development of cotton plants, and that the optimum time of application is the beginning of flowering.

Zintz, Miles V., Corrective Reading, William C. Brown Company Publishers, Dubuque, Iowa, 1966, 380 pp.Jordan, William C, Ed. D, “Prime-O-Tec: The New Reading Method”, Academic Therapy Quarterly, Summer, 1967.Carner, Charles “Reaching Troubled Minds Through Reading,” Today's Health, (December, 1966), 44:32-33 and 75-77.Stephens, W. E. Cunningham, E., and Stigler, B. J. Reading Readiness and Eye Hand Preference Pattern in First Grade Children, "Exceptional Children,” March, 1967, pp 481-488.de Hirsch, Katrina, and Jansky, Jeannette J. “Early Prediction of Reading, Writing, and Spelling Ability.” Corrective Reading in the Elementary Classroom. Edited by Marjorie Seddon Johnson and Roy A. Kress. Perspectives in Reading No. 7. Newark, Del.: International Reading Association, 1967.

Six Gossypium hirsutum L. cultivars were compared under conditions of wide (40 cm) and normal (10 to 12 cm) spacing between plants, with 1 m between rows. Plant spacing had no significant effect on boll weight, boll retention, fiber length uniformity, or fiber strength or fineness. Lint percent was increased and fiber length was decreased by wide spacing, but there were no cultivar ✕ spacing interactions for these traits. Lint and seed cotton yields, boll number, and flower number (per unit area) were usually decreased by wide spacing, but significant cultivar ✕ spacing interactions were detected for these traits. ‘Acala 1517C’ and ‘Del Cerro’ were affected more strikingly than the other cultivars by plant spacing, probably because of their pyramidal plant‐type and short fruiting branches. The relative performance of genotypes for lint yield and associated traits, when evaluated under wide spacing, may therefore not be valid for more closely spaced plantings.

Lint quality was tested in six trials which were conducted from 1959 to 1965 in Israel. These trials included varieties of G. hirsutumL. and G. barbadenseL. and the F1intraspecific crosses within each species. F2's of these crosses were included in two of these trials. A small effect of heterosis for upper‐half‐mean lint length was found in both species, with the magnitude of this heterosis larger in G. barbadenseL. than in G. hirsutumL. The inheritance of this trait was found to be mostly additive, with small dominance effects in both species, and possibly also some epistatic effects in G. barbadenseL. Results for mean lint length were similar. Lint strength (Pressley tester, 1/8” gauge) of G. hirsutumL. Fl's was very close to mid‐parental performance, whereas G. barbadenseL. F1's were much closer to the parent having stronger lint. Inheritance of this trait was found to be mostly additive, with some dominance effects in G. barbadenseL. Fineness of lint (Micronaire) of intraspecific crosses of both species was found to be intermediate between parental performance, with a slight tendency of F1fibers to be coarser. Large interactions of fineness with environment were observed.

Three trials, conducted in 1964 and 1965 in Israel, included a set of four varieties of G. hirsutumL. and their intraspecific crosses in all combinations in the F1and F2generations, and a similar set of four G. barbadenseL. varieties and their F1and F2intraspecific crosses. Heterosis for lint yield was 15 to 24% and 21 to 28% in G. hirsutumL. and G. barbadenseL. intraspecific F1crosses, respectively. This was always associated with heterosis for yield of seed‐cotton and for the number of bolls produced. Heterosis for boll‐weight was found in G. hirsutumL., but was not always shown by G. barbadenseL. Heterosis for boll number was associated with a higher percentage of boll retention in G. hirsutumL. and with more flower production in G. barbadenseL. F2deviations from the average of mid‐parent and F1performances were relatively small for lint yield, indicating that although some epistatic effects may be operative for this trait, additive and dominance genetic effects are more important. In G. hirsutumL. significant F2deviations were found for lint‐index and lint‐percent, and in some cases also for seed‐index. In G. barbadenseL. a significant F2deviation was found only for flower number in one experiment.

Acid delinting improved and accelerated the germination of cotton seeds at low temperatures in tests conducted both in an incubator (at 12 C and 14 C) and in the field. All the cultivars of Gossypium hirsutumL. and G. barbadenseL., tested in these experiments, exhibited this effect, even though seeds of the latter species were covered only by a negligible amount of fuzz. This indicates that acid delinting increases the permeability of the seedcoat. Water was absorbed by the fuzz during the first hours after planting, but later acid‐delinted seeds showed a higher rate of water absorption. The inheritance of the ability of cotton seeds to germinate at low temperatures is probably polygenic and primarily additive, with prominent maternal effects which are associated with characteristics of the seedcoat and the fuzz.

The optimum amount of water, applied as a single irrigation to cotton ‘Pima 32’ variety at the beginning of flowering, was that needed to wet the soil to a depth of approximately 90 cm. A higher amount of water, though inducing more vegetative growth and flowering, did not produce lint yield, boll size, or number of harvested bolls exceeding this optimum treatment. An amount of water less than the optimum was less effective.