Lena Chemical (Czechia)

Varying fiber length distributions of cotton, Gossypium hirsutum L., impacts its spinning performance. Advanced Fiber Information System (AFIS) facilitates the analysis of the length distribution of individual fibers in cotton. Quantile regression is a variant of standard regression with which conditional quantile values can be calculated by minimizing weighted sums of absolute deviations across the entire distribution. Quantile regression was used to analyze AFIS fiber length distribution among five genotypes of upland cotton grown at the Texas Agricultural Experiment Station Research Farm near College Station, TX during 2001 and 2002. The shape of the distribution of ‘CAMD‐E’, a short‐staple variety, was actually similar to ‘Acala 1517‐99’, a long staple variety with good spinning quality, even though CAMD‐E had consistently lower fiber lengths. ‘FM 832’, and ‘TAM 94L‐25’ had similar mean fiber lengths to Acala 1517‐99, but their distribution shape was less skewed. ‘TTU 202’ had high cross entropy values, but little difference was detected in distribution shape by quantile regression. Year had a significant impact on distribution of fiber lengths, affecting distribution scale and location, which may be due to lower fiber fineness and maturity in 2001. Quantile regression was found to be an effective method for analyzing AFIS fiber length distributions, although further testing with a larger set of genotypes and environments with spinning data is needed.

Abstract Glyphosate is a broad-spectrum herbicide effective on deep-rooted perennial species and on annual and biennial species of grasses, sedges, and broadleaf weeds. The solubility of glyphosate acid is relatively low in water, 12 g/L (25°C). Since glyphosate is an acid, however, numerous water-soluble salts can be formed. Recently, formulations have been developed that avoid the need to make salts. Instead, the glyphosate is presented in the acid form. Unlike traditional glyphosate salt formulations, that need surfactants to enhance their uptake, the acid formulation of HM-2028 does not rely on reduced surface tension or other surfactant effects to provide excellent uptake and herbicide efficacy.

Many agricultural spray adjuvants utilize one or more organosilicone surfactants in their composition. These materials have been shown to provide biological efficacy enhancement to agrichemicals and/or correct spray application problems. Commercial adjuvant products that utilize organosilicone surfactants are currently formulated only as liquid products. In recent years, many pesticide products have been introduced as dry formulations. These formulations have provided growers and applicators with the advantages of reduced exposure, improved storage stability and easier package disposal. Until now, the technology necessary to produce dry adjuvants utilizing organosilicone surfactants has been unavailable. Two formulation technologies now provide the option for developing dry organosilicone spray adjuvant products; a.) dry co-surfactant blends of organosilicone and propylene oxide/ethylene oxide copolymers and b.) organosilicone impregnated on dry carboxylic acid salts. Laboratory evaluations, regarding the surface chemistry properties of these dry organosilicone adjuvants, compare favorably with those from the traditional liquid formulations. The purpose of this research was to determine if glyphosate efficacy enhancement provided by dry organosilicone based adjuvant products, is comparable to control levels of liquid organosilicone based adjuvant with glyphosate and to evaluate the impact of dry surfactant formulation variables. The field efficacy experiments were conducted at eight locations in the northern and southern regions of the United States, to evaluate glyphosate activity on various annual and perennial weed species. The experimental adjuvants were tank mixed with a glyphosate formulation that did not contain surfactant. A 731 mL/ha rate of glyphosate was applied at seven of the sites, with one location having had al462 mL/ha rate applied. HM9208-A and HM9507 (dry formulations of organosilicone surfactants), were applied 453.6 grams/379 liters of spray solution. HM9220 (a liquid formulation of organosilicone surfactant), was applied at 0.125% v/v concentration. All treatments were applied at 94 L/ha spray volume. Applications to quackgrass, perennial ryegrass, rhizome johnsongrass, alfalfa and annual fleabane resulted in greater levels of weed control due to the addition of HM9208-A versus HM9507 or HM9220. Applications to Timothygrass resulted in equivalent control levels among the three adjuvants. At a site in Mississippi, glyphosate plus HM9208-A provided better control of goosegrass and southwestern cupgrass when compared to the addition of HM9507. Control levels were equivalent on these two weed species with either HM9208-A or HM9220.