Cotton Plant Parts Research Articles

Systemic Activity of 2-Methyl-2-(methylthio)propionaldehyde O-(methylcarbamoyl)oxime (UC-21149) in the Cotton Plant with Special Reference to the Boll Weevil123

Bioassay of parts of cotton plants that had been sidedressed with 2-methyl-2-(methylthio) propionaldehyde O-(methylcarbamoyl) oxime (Union Carbide UC-21149) showed that the greatest amount of toxicant accumulated in older leaves and the least in debracted squares (floral buds). One sidedress application of 4 lb toxicant per acre or 2 sidedress applications of 2 lb per acre effectively controlled Anthonomus grandis Boheman, in field cages; however, 2 applications were more effective. When the same total amounts of UC-21149 were applied as multiple and single sidedressings, the multiple applications resulted in greatest uptake in new plant growth. Both deep placement in the soil close to the cotton plant and irrigation increased the uptake of sidedressed UC-21149, but placement did not affect uptake when the soil was irrigated. Foliar applications of a cottonseed oil feeding stimulant increased the effectiveness of a sidedressing of UC-21149 After soil applications, the S35-labeled sulfoxide of UC-21149 [2 methyl-2-(methylsulfinyl) propionaldehyde O-(methylcarbamoyl) oxime] was the major toxic component of squares. After stem applications 8.6–24.2% of the radiolabeled compound was recovered in the plant above the point of treatment.

Corn and Cucurbits from Wetherill Mesa

AbstractMost corn from the Mesa Verde area belongs to a complex derived from hybridization of a small-cobbed flint-pop corn with an 8-rowed flour corn. This cross produced 12- to 14-rowed flint and flour corn (the typical Basketmaker corn) and the variable Pima-Papago corn. After Pueblo I, probably late Pueblo II, there was an increase in the number of 8-rowed cobs and a decrease in 12- to 14-rowed cobs. The corn is similar to collections from sites of comparable age excavated in northern Arizona near Navajo Mountain. The uniformity and the slow development of corn types probably reflect peripheral conditions, especially adaptation to short growing seasons and limited cultural interchange.Practically all of the squash was Cucurbita pepo, the species which spread over all agricultural areas of the United States. There were a few specimens of Cucurbita mixta and of the bottle gourd, Lagenaria siceraria. Some rinds of the two species of Cucurbita gave evidence of their use for scrapers and containers, uses to which the bottle gourd is put almost exclusively in sites to the south. The rarity of the bottle gourd and the absence of seeds and plant parts of cotton suggest that these plants were rarely, if ever, grown in the region.

Methods of Evaluating the Chemotropic Response of Boll Weevils to Extracts of the Cotton Plant and Various Other Substances1

Two methods are described for testing the chemotropic response of the boll weevil, Anthonomus grandis Boheman, to various substances. In one method, solutions of pure chemicals or extracts of the cotton plant were applied to a feeding dish containing diet. In the other, plant parts were placed in a small container covered with a paraffin film to prevent contact of the test material by the insect. The behavior of the boll weevil in both assay methods is described and the applications of the methods are discussed. A solvent extraction of cotton plant parts and the chromatography of the extract are described. By the use of the diet method, several fractions attractive to the boll weevil were found.

An Arrestant and Feeding Stimulant for the Boll Weevil in Water Extracts of Cotton-Plant Parts1

A powerful arrestant and feeding stimulant for boll weevils (Anthonomus grandis Boheman) was found to exist in water extracts or all cotton-plant parts and square components investigated. A biological assay method was developed by utilizing agar plugs impregnated with the extract and wrapped with filter paper, to determine quantitatively the concentration of the arrestant. All the cotton plant parts investigated were found to contain the arrestant in sufficient concentration for bioassay. Flowers at the stage or anthesis and whole squares contained the highest. In the square, the exterior component (calyx) contained the highest but the amount progressively decreased interiorly, with the lowest in the ovary. Presence of the arrestant and feeding stimulant in germinated seed or seedlings indicated they could be used as screening agents in host-plant resistance programs, obviating need for fruiting plants. Correlation between weevil feeding response and concentration was almost direct, with the bottom limit at 10,000 p.p.m. Agar plugs with small amounts of water extract from squares elicited a much higher feeding response than a commonly used artificial adult-weevil diet.

Osmotic Adjustment of Plants to Saline Media. I. Steady State

Bernstein, Leon. (U. S. Salinity Lab., Riverside, Calif.) Osmotic adjustment of plants to saline media. I. Steady state. Amer. Jour. Bot. 48(10): 909–918. Illus. 1961.—The osmotic pressure (OP) of roots, as well as the OP of aboveground parts of cotton and pepper plants, increase pari passu with increases in the OP of the medium over as wide a range of salinity as would permit any growth. New plasmolytic and cryoscopic techniques yield comparable OP values for roots when dilution of cell sap by the free-space solution and by endosmosis during rinsing of roots are taken into account. Since OP differentials between plant parts and root media are maintained, turgor does not decrease and growth inhibition by salinity cannot be attributed to water stress in the sense of lowered plant turgor. Some alternative mechanisms for osmotic inhibition of growth are considered and the osmotic adjustment process itself is indicated as a likely limiting factor for growth under saline conditions. Osmotic adjustment of cells to salinity depends in part on increased accumulation of ions and also on substitution of monovalent for polyvalent ions. The relative importance of increased salt accumulation, ionic substitution and increased non-electrolyte concentration varies with organ (leaf or root), leaf age and salinity level.

OSMOTIC ADJUSTMENT OF PLANTS TO SALINE MEDIA. I. STEADY STATE

Bernstein, Leon. (U. S. Salinity Lab., Riverside, Calif.) Osmotic adjustment of plants to saline media. I. Steady state. Amer. Jour. Bot. 48(10): 909–918. Illus. 1961.—The osmotic pressure (OP) of roots, as well as the OP of aboveground parts of cotton and pepper plants, increase pari passu with increases in the OP of the medium over as wide a range of salinity as would permit any growth. New plasmolytic and cryoscopic techniques yield comparable OP values for roots when dilution of cell sap by the free‐space solution and by endosmosis during rinsing of roots are taken into account. Since OP differentials between plant parts and root media are maintained, turgor does not decrease and growth inhibition by salinity cannot be attributed to water stress in the sense of lowered plant turgor. Some alternative mechanisms for osmotic inhibition of growth are considered and the osmotic adjustment process itself is indicated as a likely limiting factor for growth under saline conditions. Osmotic adjustment of cells to salinity depends in part on increased accumulation of ions and also on substitution of monovalent for polyvalent ions. The relative importance of increased salt accumulation, ionic substitution and increased non‐electrolyte concentration varies with organ (leaf or root), leaf age and salinity level.

Feeding and Oviposition by the Boll Weevil on Artificial Diets

Artificial diets are described for the adult boll weevil ( Anthonomus grandis Boh.). Basal diets contained an enzymatic liydrolyzate of casein, glucose, corn oil, cholesterol, Wesson's salts, choline, ascorbic acid, B vitamins, water, and agar. Mixed pollen in amounts of 0.1 to 5 grams per 100 grams of the basal diet stimulated feeding and oviposition. Five generations of weevils were obtained on artificial diets without cotton-plant parts by rearing from egg to adult on a soybean protein diet and allowing the adults to feed and oviposit on a diet containing mixed pollen. Oviposition occurred when pollens from different families of plants were used. The only substance other than pollen that appreciably stimulated oviposition was wlieat germ. A basal diet containing homogenates of heated cottonplant parts, squares, flowers, germinated cottonseed, and young green seedlings also caused weevils to feed and oviposit. Tests with modifications of the basal diets are described. Substances that repelled the boll weevil when included in the basal diets were alfalfa meal, forage juice, distiller's dried solubles, yeast extract, and beef extract.