Merle D. Witt

Performance of wheat variety blends in Kansas

This report is brought to you for free and open access by New Prairie Press. It has been accepted for inclusion in Kansas Agricultural Experiment Station Research Reports by an authorized administrator of New Prairie Press. Copyright 1980 Kansas State University Agricultural Experiment Station and Cooperative Extension Service.

Seed Treatment Effects on Early-Season Pests of Corn and on Corn Growth and Yield in the Absence of Insect Pests

Abstract Second-generation neonicotinoid insecticides are being used to protect seeds and seedlings against injury by early season insects on a wide variety of crops. Seed-applied insecticides have recently been commercialized in the USA for early season insect control in corn. The systemic insecticides clothianidin (Poncho®) and thiamethoxam (Cruiser®) applied as seed treatments were evaluated for their effect on corn yield in the absence of noticeable insect attack over a three year period at a number of locations representing diverse growing environments in Kansas. No consistent effect on yield was detected for either compound at either high or low rates in locations where insects were not observed at damaging populations. Controlled-environment studies detected no differences in early season growth in the absence of insect pests in response to the same two rates of both insecticides. Both compounds were evaluated for their effect on early season corn pests and were found to be effective at high and low rates on wireworm, white grub, flea beetles and chinch bugs. Higher rates of both compounds were needed to reduce feeding damage caused by black cutworm. Seed treatments with either compound would be useful where early season pests are chronic problems.

Selection for increased in vitro digestibility improves feeding value of sorghum grain

Six cannulated barrows and two hundred eighty-eight chicks were used in an experiment to determine the value of an in vitro protein digestibility assay (pepsin digest) for identification of sorghum parent lines with improved nutritional value. The barrows were used to determine digestibility of the experimental sorghums at the terminal ileum and for the total digestive tract. Due to a limited supply of the sorghums, broiler chicks were used as a model to predict the value of the experimental sorghums for growth performance. Four sorghum parent lines were selected from 100 SI families grown at several locations in Kansas. Two of the sorghums were consistently low and two were consistently high for in vitro digestibility. Treatments were: 1) corn-soybean meal control; 2) and 3) low digestibility sorghums (LDI and LD2); 4) and 5) high digestibility sorghums (HDI and HD2); and 6) pearl millet (PM). The sorghums that had consistently high in vitro digestibility were of greater nutritional value to pigs and growing chicks than sorghums with low in vitro digestibility. In the pig experiment, digestibility of N at the terminal ileum ranged from 69.6% for LDI to 79.0% for HDl, compared to 81.6% for the corn-based control. Similar responses were noted for digestibility of gross energy, with values of 71.8% and 77.0% for LDI and HDl, compared to 80.2% for the corn-based control. The HD lines were equal or nearly equal to corn in the chick growth assay, with efficiencies of gain that were 98 and 100% that of corn for HD1 and HD2, respectively. Pearl millet was of greater feeding value than sorghums for chicks but less digestible than sorghums in pigs. These data suggest that in vitro pepsin digestibility can be a valuable tool for sorghum breeders to select parent lines with improved feeding value.; Swine Day, Manhattan, KS, November 21, 1991

Effects of application of water and nitrogen on nutrient use from corn and sorghums by pigs

An experiment was conducted to determine the effects of growing conditions on nutrient yield and quality of corn and sorghum. Main effect treatments were: corn (C), bronze pericarp heterozygous-yellow endosperm sorghum (BS), and yellow pericarp homozygous-yellow endosperm sorghum (YS); optimal irrigation (I) and minimal irrigation (MI); 100 lb/acre of N fertilization (F) and no N fertilization (NF), in a 3 × 2 × 2 factorial arrangement. Grains were grown in 1988 (Year 1, with little rainfall) and 1989 (Year 2, with above average rainfall) in the semi-arid environment at Garden City, KS. In Year 1, sorghums yielded 15% more grain than C, and YS yielded 1.2% more grain than BS. Irrigation increased yield by 90%, and N application increased yield by 7%. In year 2, C yielded 11% more grain than the sorghums. In the pig metabolism study, C had greater nitrogen digestibility (ND) than sorghums in both years, greater biological value (BV) and nitrogen retention in Year 2, but lower BV in Year 1. Yellow sorghum had greater ND than BS in Year 1. Corn had increased cost per unit of utilizable nitrogen (CUN) and utilizable energy (CUE) and reduced utilizable nitrogen per inch of available water (UNW) and utilizable energy per inch of available water (UEW) for both years compared to BS and YS. In conclusion, optimally irrigated grains had higher nutritional value than minimally irrigated grains, and growing the grains under varying agronomic conditions did affect their nutritional quality.

Response of BT Corn to Simulated Hail Damage

Hybrid corn is grown annually on approximately 3.1 million acres in Kansas and is an important part of agricultural production under both dryland and irrigated conditions. This corn acreage is subjected to hail damage of various degrees each year. Numerous studies have examined the effect of hail damage on the grain production of conventional corn hybrids. However, data have not been published regarding the effect of hailstorm defoliation on the new genetically modified corns resistant to European corn borer. Thus, we undertook to evaluate the influence of simulated hail defoliation on conventional corn hybrids versus Bt-corn hybrids, which have the Bacillus thuringiensis (Bt) gene added.

Two-year test results suggest caution with dinoseb as a yield stimulant for corn or grain sorghum

This report is brought to you for free and open access by New Prairie Press. It has been accepted for inclusion in Kansas Agricultural Experiment Station Research Reports by an authorized administrator of New Prairie Press. Copyright 1977 Kansas State University Agricultural Experiment Station and Cooperative Extension Service.

Effects of alfalfa on wheat establishment

Alfalfa is a high value crop in southwest Kansas and is produced on about 220,000 acres. Approximately 50,000 of these acres are rotated to some other crop each year. The roots of alfalfa varieties have been reported to produce differing amounts of saponin, medicarpin, and phenolics, all water-soluble toxic materials that can inhibit growth of the succeeding crop. Although toxicity is less of a concern when seeding grasses into alfalfa than when reseeding alfalfa, it might affect wheat establishment and production, and variety differences have not been evaluated. The objective of this study was to evaluate currently utilized alfalfa varieties and identify those with an unusually large undesirable toxic influence upon the following crop of wheat.

Evaluation of late planting opportunities for winter wheat

Winter wheat in the Great Plains is not always planted at the optimum time for several reasons. Sometimes unwanted circumstances occur, including necessary replanting following stand loss to wind, pests, or winter killing. In other cases, the seedbed may be too dry or too wet to plant at a normal time. Additionally, planting may be delayed purposely in order to avoid diseases or insects, to pre-irrigate, or to accommodate a double-cropping sequence. This study was conducted to quantify the relative grain yields of winter wheat that might be expected over the wide range of potentially usable dates.

Soybean choices for iron-deficient soils

This report is brought to you for free and open access by New Prairie Press. It has been accepted for inclusion in Kansas Agricultural Experiment Station Research Reports by an authorized administrator of New Prairie Press. Copyright 1974 Kansas State University Agricultural Experiment Station and Cooperative Extension Service.