Showing papers on "Cultivar published in 1970"

Synthesis of Cellulase during Abscission of Phaseolus vulgaris Leaf Explants

Abstract: When abscission in leaf explants from Phaseolus vulgaris, cultivar Red Kidney, was allowed to proceed while the explants were in (2)H(2)O, a 1.25% increase in the buoyant density of cellulase in a cesium chloride gradient was observed. These data indicate that the increase in cellulase activity during abscission is a result of the synthesis of new protein. Two differentially soluble forms of cellulase are present in the abscission zone. The form which is soluble only in a high salt buffer seems more closely related to the abscission process than the form which is soluble in dilute buffer. The correlation between changes in pull force and increase in cellulase activity and the effects of several hormones on cellulase activity are discussed.

Comparison of endogenous gibberellins and response to applied gibberellin of some dwarf and tall wheat cultivars.

Abstract: A number of dwarf wheat cultivars of the Norin 10 type were compared with several tall forms. Applied gibberellic acid markedly stimulated the growth of seedlings of the tall cultivars but not the growth of dwarf seedlings. Several other gibberellins were also inactive when tested with one dwarf cultivar. De-embryonated grains of all cultivars formed α-amylase in response to gibberellic acid. Gibberellic acid caused an increase in soluble carbohydrates in the leaves of the tall cultivars but not in those of the dwarfs. Germinating grains, light-grown seedlings and developing stems of the dwarf cultivars contained more endogenous gibberellin-like activity than those of tall cultivars. It is suggested that the dwarf cultivars have a block to the utilisation of gibberellin in the shoot.

Effects of vernalization, photoperiod, and temperature on phonological development and spike-let number of Australian wheat.

Abstract: Sixteen Australian wheat cultivars grown in controlled environment cabinets demonstrated a range of responses to seed vernalization varying from little or no promotion of floral initiation in Darkan, Kondut, Falcon, and Sunset to about 3 weeks in Festiguay, Claymore, and Mexico 120. Under short days (10 hr photoperiod v. 14 hr) or cold temperatures (12/7¦C day/night v. 18/13¦) the response to seed vernalization was reduced. None of the cultivars responsive to vernalization achieved floral initiation earlier under cold temperatures than under warm temperatures, even in the absence of seed vernalization. All cultivars achieved floral initiation earlier in long days but the magnitude of the response varied considerably among them. Long days similarly accelerated development from initiation to anthesis. Higher temperatures accelerated development to initiation and anthesis in all cultivars, with only minor differences in magnitude of response. Selected treatments in the cabinets gave rates of development to initiation which closely paralleled results for the same cultivars in field experiments. The number of spikelets per head varied considerably with cultivar, day length, and vernalization treatment. Within the range of conditions of the experiments, temperature did not affect spikelet number other than through vernalization. At either temperature, the spikelet number was closely and positively related to the number of days to floral initiation.

Some effects of barley yellow dwarf virus on spring and winter cereals in field trials

Abstract: SUMMARY The tolerance of spring and winter cultivars of wheat, barley and oats to infection by barley yellow dwarf virus (BYDV) was examined in field tests. Sererely affected plants were stunted and grain yields were considerably reduced. These changes in infected spring barley cultivars were associated with decreases in both ear length and number and sizes of grain. Most barley and oat cultivars were more susceptible than wheat cultivars. Yield losses decreased with successively later dates of inocultaiton, the yield response being characteristic of the tolerance of individual cultivars. Differences between tolerant and susceptible cultivars were insignificant in most cases where infection occurred after growth stage 7. Individual seedling symptoms assessed in April and May were more closely related to each other and to yield losses than those recorded in March and June. The incorporation of seedling symptoms into indices of infection permits estimates of decrease in yield to be made by applying the formulae, DY = (LC+LA+SH)/3 to barley cultivars and DY = 1.7 × (LC+LA+SH)/3 - 7 to oat cultivars. Thus decreases in grain yield (DY) can be related to decreases in seedling height (SH) and increases in percentage of leaf area discoloured (LA) and intensity of discoloration (LC). Plot symptoms of infection, scored on a 0–7 scale, offered a more convenient method of assessment than individual seedling symptoms. Plot scores (PA) were closely correlated with other seedling symptoms and with decreases in grain yield (DY), and can thus be used to estimate yield losses by substituting into the formula, DY = 14PA (April)-8. This formula was found to be applicable to all cereal cultivars examined in N.I.A.B. trials, there being no distinction between wheat, barley and oats.

The Effect of Early Low Temperature Treatment on the Yield of Single-Inflorescence Tomatoes

Abstract: SummaryA short period at an average temperature of 10° C. during the early growth of tomato plants increased the number of flowers on the first inflorescence. The yield of these plants, whose vegetative apex was removed after the first inflorescence, was approximately 25% greater than that of similar unchilled controls. Fruit number was increased still more ; average fruit weight diminished, and there were fewer very large fruit of low market value. Similar increases in yield were obtained from plants sown throughout the year, except from a September sowing when there was no increase. Chilling delayed harvesting by about four days with summer sowings and rather more in winter, but had little effect on the duration of the harvesting period.Increase in flower number may not have been the only cause of the increased yield. The possibility of a direct effect of the cool period on yield is discussed.The cultivar Minicraigella was more suitable than Minipotella for growing as a single-inflorescence plant since ...

The relation of seed vigour to field establishment of garden pea cultivars

Abstract: SUMMARY Emergence trials of five different seed lots each of cv. Lincoln and Kelvedon Wonder at six centres provided 27 different sowing treatments. Although mean emergence between treatments varied, the rank order of the lots remained almost constant. The results of seedling evaluation and conductivity vigour tests correlated well with field emergence, with neither test superior to the other. Grades of vigour were established and related to the performance of the seed lots in the field trials.

Metabolic responses of bush bean plants to naphthenate application.

Abstract: A 0.5% aqueous spray of potassium naphthenates was applied to the foliage of 14-day-old plants of bush bean, Phaseolus vulgaris L. cultivar Top Crop, and the plants were then grown under light intensities of 16.1, 10.76, and 5.38 klx at 26 °C for 7, 14, and 21 days. Photosynthesis, dark respiration, and phosphorylase activity were significantly greater (0.05 level) in treated plants at the end of all three growth periods under all light conditions. Significant stimulation of phosphoglycerate kinase developed more slowly under the lower light intensities. The stimulation of nitrate reductase and glutamic–pyruvic transaminase in treated plants reached a significant level between 7 and 14 days after treatment, and subsequently increased. The percentage increases of all the processes, over corresponding values in control plants, were greatest in plants grown at the highest light intensity.

Effects of cultivar and plant age on vegetative growth of the strawberry, fragaria ananassa

Abstract: Growth of strawberry plants (Dunlap, Sparkle, and Catskill) in the greenhouse was affected by the time of rooting of the runners in the field. This was shown by more rapid leaf and leaf-area production, larger leaf size, more runners and root growth on the older compared to the younger runner plants. The oldest plants also produced the greatest number of flower buds, but the time of bloom was not appreciably affected. The growth responses of plants of different sizes were similar to those of plants of different ages. These growth responses were most apparent during the first stages of growth, but the resulting differences frequently persisted for several months. Significant differences between cultivars were also found. Initially the greatest leaf size and leaf area were produced by Catskill plants. Because of a higher leaf production rate, Sparkle plants eventually had the largest leaf area. Sparkle plants were the last to flower and also to initiate ruinner production. Dunlap plants were the first to flower and produced the largest number of flowers. In the field, leaf production records indicated responses from cultivars and plant age similar to those found in the greenhouse. THE NEED for specific information on strawberry plant growth was recognized as early as 1898 by Goff. Since then information on many aspects of growth has been reported, but emphasis has been on factors directly affecting yields. Thus it is known that different cultivars vary in the extent of runner production (Loomis, 1938; Morrow, 1938; Smeets, 1956), and older or larger runner plants produce more fruit (Davis and Blair, 1938; M\orrow and Beaumont, 1932; Rogers, 1931; Schilletter and Richey, 1930). Cultivars also have been shown to differ in flowering (Darrow, 1929b), leaf area (Darrow, 1930), and root development (Hanson, 1931). Older runner plants have been associated with greater runner development (Darrow, 1929a; Davis, 1922) and leaf size (Darrow, 1930). Smaller runner plants were found to be later in starting runner production (Darrow, 1929a; Peacock, 1939) and produced fewer flowers (M\lorrow and Darrow, 1940; Rogers and Edgar, 1938). Leaf production on plants has been related to the number of flowers produced (Morrow and Darrow, 1940; Sproat, Darrow, and Beaumont, 1936), and correlations as high as .75 have been found between leaf area and the weight of fruit produced on the plant (Pickett, 1918). Consistent developmental patterns in the Royal Sovereign strawberry have been shown in the I Received for publication 5 March 1970. Approved for publication by the Director of the Research Division, College of Agricultural and Life Sciences, Universitv of Wisconsin. This investigation was supported in part by a grant from the Research Committee of the Graduate School from funds supplied by the Wisconsin Alumni Research Foundation. 2Present address: Market Quality Research Division, Agricultural Research Service, U.S.D.A., Orlando, Fla. extensive studies reported by Arney in England. The present studies were undertaken to obtain more extensive and specific information on strawberry plant growth and also to compare growth patterns on several cultivars grown under the same conditions. MATERIALS AND METHODS-The strawberry plants used in these studies were of three cultivars: Dunlap, Sparkle, and Catskill (Fragaria ananassa). To obtain populations of plants of different ages, developing runner plants with the second trifoliate leaf emerging were marked in the field. This stage represents the approximate time at which rooting occurs. Similar groups of plants were selected on 7 and 29 August and 18 September 1957. These will be referred to as ages 2, 4, and 6. In 1958 seven age-groups were obtained. Age 1 plants were rooting on 2 July, and agegroups 2 through 7 were selected at intervals between 6 August and 1 October. All plants were well established in the field before becoming dormant near the end of October. At this time plants in group 7 had about three leaves compared to about 11 in age-group 1. Plants were dug in early November and stored at 32-35 F until experimental plantings were made. Experiment 1 was set up in the greenhouse on 11 January 1958. Six replications of each of the three age-groups and three cultivars were included. Experiment 2, set up on 2 January 1959, also included six replications of the three cultivars but with the seven age-groups of plants which had been selected in 1958. Wide differences in plant size occurred between plant age-groups. In Experiment 2 Dunlap plants averaged from 1.6 g

Lychee Cultivars in Hawaii

Abstract: The Hawaiian commercial cultivars described were developed and selected especially for grow ing conditions in Hawaii. Important macadamia growing enterprises have not developed in other parts of the world as a result of introduction of Hawaiian cultivars. There has been considerable macadamia promotional activity recently how ever in several areas, notably California, Rho desia, Costa Rica and Queensland, Australia. Hawaiian cultivars have been introduced for testing in all of these places. Plantings made in these areas have not yet attained sufficient production for commercial processing however and variety testing is only in the preliminary stage. Because growing conditions in these areas differ from those of Hawaii, it may be expected that clones selected in these countries may eventually prove better adapted and more productive than imported Hawaiian cultivars. Wherever frost becomes a factor, M. tetraphylla selections and hybrids of M. tetraphylla and M. integrifolia which tolerate light frosts better than M. integrifolia can be expected to perform better than the Hawaiian M. integrifolia cul tivars.

The weight of the mature wheat grain.

Abstract: Grains retained on the plants of some cultivars of common bread wheat lose dry matter after ripeness is attained, but later gain dry matter again. We conclude that the post-ripe plant may remain metabolically active.

Response of cauliflower cultivars to molybdenum deficiency

Abstract: Studies were carried out to determine the basis for differential sensitivity between cauliflower cultivars to molybdenum deficiency. Results indicate that the cultivar Pioneer is not as efficient as Snowball 84 in the uptake of Mo. Requirements of Mo to produce optimum yields were quite similar for both cultivars, being approximately 1.9 kg/ha.

Competition effects on yield and plant and tiller density in mixtures of rye-grass cultivars.

Abstract: The rycgrass cultivars, Grasslands Manawa and Grasslands Ruanui, were grown in simulated swards in replacement series under systems involving a 2X2 arrangement c.f height and frequency of cutting. Estimates of plant survival at two dates indicate greater overall mortality in the Manawa population. In the earlier part of the experiment the death of Manawa, and of Ruanui plants particularly when mixed with Manawa-was greater under infrequent than frequent cutting. This effect is mainly attributed to competition for light excluding more prostrate individuals. In the latcr period drought was probably the important factor determining the survival of plants, with Manawa plants of small size and at high densities being most susceptible. Examination of the frequency distribution of tiller number per plant at three sampling datcs showed trends similar to those obtained by Koyama and Kira (1956). The frequency distri. butions were approximately normal at the earliest sampling dalte but became progressively more skewed towards L-type distributic.ns later. The skew was more pronounced for Manawa and was emphasised for Ruanui when it was the minority component in mixture with Manawa. Infrequent cutting promoted the development of a skewed distribution. Changes in the relative reproductive rate of the cultivars with change in the proportion of the cultivars in the mixtures were examined by the use of ratio diagrams. These indicated a general trend of greater relative reproductive rate of Manawa when it was so\vn at a ratio low in comparison with the intermediate seeding ratio. Thereafter the relative reproductive rate remained constant or increased at higher seeding ratios of Manawa.

The measurement of certain physical characteristics related to rapid germination and seedling vigor in cottonseed.

Abstract: Investigations were conducted to relate the physical characteristics of cotton seed to germ (germination), subsequent plant growth, and final plant develop ment. The effects of length, diam (diameter), wt, volume, and dens (density) on the seed's ability to germinate and grow were determined. Procedures for a nondestructive measurement of a single seed's volume and density were developed. Visual germ cells also were developed to observe the germ at 24-hr intervals without losing the identity of individual seeds and without disturbing the young sdls (seedlings). The influence of seed density on germ was highly significant in the individual seed studies. Seed wt apparently had the most influence on sdl growth. Seed dens had such a strong influence on the earliness of germ that it over shadowed the influence of seed wt on growth in a combined analysis of germ and growth response. Design of cottonseed selection equipment should be based on dens. The level of seed dens to be culled will depend on the cv (cultivar) deterioration level of the seed lot, and the economics of supply and demand. Additional separation should be made on the basis of seed wt to cull out the light seed. Additional index words-, density, displacement, germination cells, selection equipment, volume, weight.

Salinity response of cultivars of buffel grass (Cenchrus ciliaris)

Abstract: Five buffel grass cultivars were grown in solution culture at levels of 0.5, 40, 80, and 160 m. equiv. NaCl/l. Yields did not differ between cultivars at the highest level of NaCl, and the more productive cultivars under low salinity conditions, Tarewinnabar, Biloela, and American, suffered greatest potential yield reduction and accumulated highest sodium concentrations. Biloela cultivar maintained relatively high yields up to the 80 m. equiv. NaCl/l level.

Correction - Salinity response of cultivars of buffel grass (Cenchrus ciliaris)

Abstract: Five buffel grass cultivars were grown in solution culture at levels of 0.5, 40, 80, and 160 m. equiv. NaCl/l. Yields did not differ between cultivars at the highest level of NaCl, and the more productive cultivars under low salinity conditions, Tarewinnabar, Biloela, and American, suffered greatest potential yield reduction and accumulated highest sodium concentrations. Biloela cultivar maintained relatively high yields up to the 80 m. equiv. NaCl/l level.

Resistance of tomato cultivars and progenies to fruit hollowness

Abstract: In field experiments with fall and winter tomatoes, the incidence of fruit hollowness was found to range from 0 to more than 80%, depending both on the cultivar and the environment. The most resistant cultivars were Bonner Beste and Potentate; the most susceptible were Exhibiton, Moneymaker, E.S. 1, Berco, Cromco and Ailsa Craig. The rate of hollowness of F1 and F2 generations of crosses between resistant and susceptible parents suggests that resistance behaves as a partially dominant character governed by a small number of genes. Thus, commercial F1 hybrids resistant to the disorder are easy to produce. The heritability of the resistance character was found to be rather high.