Corn Foliage Research Articles

Metabolism of a Pyrrolidine Urea Herbicide in Corn and Weeds

Five 2,5-dimethyl-1-pyrrolidinecarboxanilides were effective inhibitors of the Hill reaction. However, only thecisisomers were active; thetransisomers were totally inactive. Experiments were conducted using14C-5328 (cis-2,5-dimethyl-1-pyrrolidinecarboxanilide). A correlation existed between resistance of various plants to 5328 and their ability to metabolize it to water soluble metabolites. Velvetleaf (Abutilon theophrastiMedic.) and proso millet (Panicum miliaceumL.) seedlings were very susceptible to 5328 and were unable to metabolize it. Tall morningglory [Ipomoea purpurea(L.) Roth] seedlings were highly tolerant to 5328 and converted it completely to its metabolites. Corn (Zea maysL. ‘DeKalb variety XL-45′) seedlings which were slightly susceptible to 5328 injury were able to metabolize up to 90% of the parent compound. Corn foliage uptake of14C-5328 applied to the soil surface occurred through the adventitious roots.

NN‐DIALLYL‐αα‐DICHLOROACETAMIDE AS AN ANTIDOTE FOR EPTC AND OTHER HERBICIDES IN CORN

Summary. The efficacy of NN‐diallyl‐αα‐dichloroacetamide (R‐25788) as an antidote for reducing the injury of various herbicides in corn (Zea mays L.) was tested under controlled conditions in growth rooms. The application of R‐25788 to the soil as a pre‐plant incorporated treatment to corn significantly reduced the toxicity often out of twenty‐two herbicides tested. These ten herbicides were, in order of decreasing effectiveness of the antidote, EPTC, barban, sulfallate, vernolate, molinate, butylate, alachlor, pebulate, linuron and di‐allate. In quartz sand nutrient culture, R‐25788 was more effective as an antidote for barban applied to the foliage of corn than it was for barban applied to the roots. Le NN‐diallyl‐αα‐dichloroacétamide comme antidote de I'EPTC et autres herbicides dans le mais.

Effect of Some Antitranspiration Chemicals on Photosynthesis and Respiration of Corn and Soybean Seedlings

Film-forming and stomatal-regulating antitranspiration chemicals significantly decreased transpiration 24 hrs after application to foliage of corn and soybean seedlings. The same chemicals usually decreased transpiration more in corn than in soybean seedlings, although dark respiration rates were accelerated more in the soybean seedlings. Net assimilation (photosynthesis) rates were not affected significantly. Several antitranspiration chemicals appear promising for field testing under Kansas conditionsv Because of their known and unknown toxicity properdes, however, they should be used with caution. Trans. Kans. Acad. Sci., 75 (3), 1972. Introduction Plants transpire through their leaves nearly all the water absorbed by their roots (Gale and Hagan, 1966). Chemical antitranspirants have been studied considerably, and several have been introduced commercially to increase water-use eiciency of plants. Antitranspirants are classed as emulsions of wax, latex, or plastic; regulators of stomatal opening; and reflectors cf radiant energy (Davenport, Hagan, and Martin, 1969). Emulsions form a thin, transparent Slm on foliage that hinders escape of water vapor (Possingham, Kerridge, and Bottrill, 1969). Stomatal regulators act on guard cells around stomatal pores to reduce water vapor loss (Sivadjian, 1967; Mansfield, 1967). Reflective materials reduce leaf temperature and transpiration rates by decreasing absorption of radiant energy (Gale and Hagan, 1966; Maidner and Mansfield, 1966; Kijre, 1968; Letey and Valora, 1965; Sivadkian and Ricardo, 1966). Use of chemical antitranspirants has been reviewed (Gale and Hagan, 19G6; Waggoner and Zelitch, 1965) . Plant processes besides transpiration respond to antitranspirants (Davenport, 1967). Photosynthesis (Slatyer and Bierhuizen, 1964), drymatter accumulation (Graharn and Buchholtz, 1968), and chlorophyll content (Waisel, Borger, and Kozlowski, 1969) of plants are decreased by antitranspirants. In contrast, respiration has been shown to be Transactions of the Kansas Academy of Science, Vol. 75, No. 3, 1972. Published September 26, 1973. 1 Contribution no. 1214, Department of Agronomy, Kansas Agr. Exp. Sta. and no. 74, Kansas Water Resources Research Institute, Manhattan, Kansas. The U. S. Department of Interior, Office of Water Resources Research, providzed partial support.

A QUANTITATIVE STUDY OF FOOD CONSUMPTION AND GROWTH IN PSEUDALETIA UNIPUNCTA (LEPIDOPTERA: NOCTUIDAE)

AbstractLarvae of Pseudaletia unipuncta (Haw.), reared on corn foliage, were found to vary in the rate they were able to feed, grow, and attain maturity. Mortality varied inversely with the rate of food intake. In the fifth and sixth instars, there was a direct linear relationship between rate of food intake and daily growth, and rate of food intake and daily development. A variance of 78 to 96% in final weights of the two stages was explained by the combined effect of initial weights of larvae, food supply, duration of feeding, and food ingested. Fecundity increased with the rate of food intake of the larvae.When P. unipuncta feeds at a high rate, it is able to accelerate development, increase growth, and maintain a high reproductive potential. When the rate of food intake is low, development, growth, and fecundity are reduced for the sake of survival.

Effects of Thermal Exposure on the Foliage of Young Corn and Soybean Plants

Effects of Thermal Exposure on the Foliage of Young Corn and Soybean Plants

Herbicidal Enhancement by Certain New Biodegradable Surfactants

Four new biodegradable alkylpolyoxyethylene glycol surfactants (15-S-9, DN-65, 15-S-3, and 15-S-3A) provided excellent visual wetting of corn foliage in spray solutions of 1,1′-dimethyl-4,4′-bipyridinium salt (paraquat), 2,2-dichloropropionic acid (dalapon), and 3-amino-1,2,4-triazole (amitrole) and many combinations were equal or superior to standard surfactants Tween 20, X-77, and Osamul 95 in enhancing phytotoxicity. Exceptions were observed, apparently due to specific but incompletely understood herbicide-surfactant-plant surface interactions. All four biodegradable surfactants and Osamul 95 were slightly toxic when sprayed alone on corn foliage.

Boron Fertilization of Corn in Minnesota1

AbstractSix fields (5 soil types) of corn were treated with soluble boron at different rates and methods of application during 1961 and 1962. A fritted trace element treatment (FTE‐502) was included in 1961, but a lighter application of FTE‐504 in 1962. No boron deficiency symptoms were observed at any growth stage, either on the corn foliage or on the ears. Leaf B concentrations on untreated soil were generally related to soluble soil B. Boron applied either in the corn row or as foliar spray resulted in the highest leaf B concentrations and broadcast B resulted in a lower level. Upper corn leaves sampled in mid‐August were highest in B. Optimum leaf sampling at this time is suggested. These five Minnesota soils, having a water‐soluble B content of 0.33 to 1.58 ppm, apparently do not require B applications for maximum corn production at this time.

X‐Ray Spectrographic Analysis of Zinc, Manganese, Iron, and Copper in Plant Tissue

AbstractX‐ray spectrographic analyses for Zn, Mn, Fe, and Cu in Bermudagrass, pecan, pine, and corn foliage were made employing standard curves prepared from composite samples and from additions of the element to each sample. Interferences by various elements were determined by analysis of enriched samples. An increase in Cu concentration in Bermudagrass reduced the value obtained for Zn. First order Kα radiation was used for all elements except Cu. Interference of W Lα radiation occurred with Cu, but was reduced by using second order reflection of Cu Kα. Simplified techniques for preparing ground sample standards were examined. Results obtained by X‐ray spectrographic and chemical methods were found to compare satisfactorily in most cases.

Occurrence of Adults of the Carrot Rust Fly, Psila rosae (Fab.) (Diptera: Psilidae), on Corn Foliage at Bradford, Ontario

Adults of the carrot rust fly, Psila rosae (Fab.), are difficult to find in the field. Frequently they can be found in light to moderate numbers in some situations, occasionally in large numbers, rarely in moderate to large numbers over a period of several days. Fabricius (1794, p. 356) reported that they were found commonly on flowers in Kiel, Germany. Curtis (1860, p. 405) wrote, “The fly…was named rosae by Fabricius, being found probably sunning itself upon the leaves of rose bushes”. Several British writers observed that the flies were most numerous in the parts of carrot fields sheltered by hedges. Baker et al. (1942) wrote: “Flies were present in small numbers on certain weeds, but in considerable numbers in the hawthorn hedges”. Roebuck (1945), Wilson (1945), Petherbridge et al. (1945), and Wright et al. (1945) made similar observations. Some British writers reported flies on various plants, as follows: Whitehead (1890), on low shrubs near streams and in meadows; Smith (1921), on sallow, oak, and hazel; Petherbridge et al. (1942, 1943, 1945), on wild chervil (Anthriscus sylvestris) , hemlock (Conium maculatum), nettles, and potatoes; Wilson (1945), on coarse herbage, growing crops (especially potato), weeds (especially nettles); and Wright et al. (1946), on trees, hedges, and ditches with a thick herb covering.

EFFECTS OF 2,4-D ON INBRED LINES AND A SINGLE CROSS OF MAIZE

The use of 2,4-dichlorophenoxyacetic acid and other growth regulating chemicals as selective herbicides for weed control in crop fields has increased rapidly in the last three years. 2,4-D, particularly, has been advocated for selective control of broad-leaf weeds in grasses, including cereals. The herbicide may, however, injure the crop under certain developmental or climatic conditions. Varietal differences also may account for some of the variable effects reported for corn. In general, the cooperative reports from several experiment stations (?) indicate that applications of 2,4-D to foliage of corn in the early stages of growth may reduce yields. Of the cereal crops, corn seemed the most sensitive. Bakke and Sylwester (2) have stated that corn may be damaged if sprayed before the ears have reached the milk stage. Pre-treatment of the soil with 2,4-D resulted in a stimulation of corn growth in experiments conducted by Taylor (11). Evidence that inbred lines and hybrids may differ in percentage of affected seedlings when pre-emergence treatments of 2,4-D were made to the soil has been presented by Anderson and Wolf (i). Pridham (10) reported that the seedlings of red kidney beans from parents sprayed with 2,4-D during the ripening of pods showed characteristic 2,4-D injury. Grigsby (5) found that pollen production and floral development of ragweed were reduced or inhibited when sprayed with several of the new herbicidal compounds. According to the cooperative reports of the North Central Weed Control Conference (6), test weight and germination of grain from treated oats, barley, or wheat differed little from untreated checks except in cases where plants showed severe injury as a result of spraying. Marth et al. (9) reported that seed stalks and seed heads developed on 2,4-D treated timothy seemed unaffected, and that the germination of seed developed on plots treated in various ways was unaffected. Application of 2,4-D to the soil had no adverse effects on the viability of Kentucky bluegrass seed, but a measurable effect was found in reducing seed dormancy (8). In the classification of crop plants as to

Insecticidal Control for the Sugarcane Borer

The work of three seasons at the Louisiana Experiment Station has yielded consistent results showing that it is possible with a water-soluble dust like sodium silicofluoride to destroy at least half of the sugarcane borer larvae occurring on the exterior or burrowing through the interior of the stalks of corn or sugarcane which are the principal host plants of this species in Louisiana. With many of the more than fifty (50) materials tested thus far there has been a degree of burning of foliage of corn which is serious, but on cane which is much more resistant to chemical burn, a number of materials have been found safe and effective enough to justify extensive field applications which may at least supplement other measures in controlling this pest.