Sangamesh V. Angadi

Genotypic and environmental variation in grain, flour, dough and bread-making characteristics of Western Canadian Spring Wheat

Wheat (Triticum aestivum L.) grain, flour, dough and bread quality characteristics are strongly influencedby growing-season weather conditions. Understanding the impact of genotype, environment, and their interactions on Canadian wheat quality is important for Canada to maintain its high standard for delivery of consistent quality wheat to domestic and international customers. The effects of genotype, environment and genotype by environment (G × E) interaction on numerous grain, flour, dough and bread-making characteristics were assessed. The Canadian Western Red Spring (CWRS) cultivars were AC Barrie, Superb, AC Elsa, and Neepawa; the Canadian Prairie Spring (CPS-white) cultivar was AC Vista; and the Canadian Western Hard White Spring (CWHWS) cultivar was Snowbird. These genotypes were grown at five locations across the Canadian prairies in 2 yr to provide a total of 7 site-years of milling quality wheat for analysis. Genotype, environment and their interactions had significant effects on most parameters...

Growth and Yield of Guar ( Cyamopsis tetragonoloba L.) Genotypes under Different Planting Dates in the Semi-Arid Southern High Plains

Guar is a drought and salt tolerant summer annual legume, which could be a potential alternative crop in the semi-arid Southern High Plains. Increased use of guar gum in oil industries has increased the demand of guar globally. Planting date effects on stand establishment, physiological parameters, and yield formation of guar genotypes were investigated at the New Mexico State University’s Agricultural Science Center at Clovis, NM for two seasons (2014 and 2015). Four guar genotypes (HES 1123, Kinman, Lewis, and Matador) were tested under three planting dates (June 18, July 7, and July 22 in 2014; and June 18, July 6, and July 20 in 2015). Higher temperature and rainfall were recorded under mid-June planting than early-July and late-July plantings. Guar planted under mid-June had better stand establishment as shown by the higher number of plants m-2, better physiology as revealed by higher photosynthetic rate (Pn), transpiration rate (Tr), leaf area index (LAI), and SPAD values than early-July and late-July plantings. Guar planted under mid-June resulted in taller plants, and therefore, produced higher plant biomass than both of the July plantings. Yield attributing characteristics including clusters plant-1, pods plant-1, seeds plant-1, seed spod-1, 1000 seed weight, and harvest index (HI) were highest under mid-June planting followed by the early-July and late-July plantings, respectively. The mid-June planting increased seed yield by 26% and 55% over early-July and late-July (1399 vs. 1111 and 903 kg·ha-1) plantings, respectively in 2014; while the same increase in 2015 was 51% and 243% (1308 vs. 868 and 381 kg·ha-1), respectively. These results indicate that delaying planting beyond mid-June is detrimental to guar productivity. However, genotypes did not show any significant variation in their performance. Overall, warmer growing conditions and more precipitation under mid-June planting caused better growth and yield formation of guar genotypes.

Current status, opportunities, and challenges of cover cropping for sustainable dryland farming in the Southern Great Plains

ABSTRACT Cropping systems that integrate cover crops into crop rotations, reduce tillage intensity and frequency, and maintain residue cover have the potential to improve agricultural sustainability in drylands. However, there is much yet to learn about the benefits of cover crops in sustainable dryland farming in the southern Great Plains (SGP). We reviewed the literature on the effects of cover crops on soil organic carbon (SOC), nitrogen, soil water conservation, and crop yields in dryland cropping systems of the US Great Plains (GP), and analyzed the opportunities and challenges for integrating cover crops into dryland crop-fallow systems of the SGP. Majority of the studies in the central Great Plains (CGP) and the northern Great Plains (NGP) of the United States suggest that cover cropping improves sustainability of cropping systems through their positive effects on SOC accumulation, nutrient cycling, soil erosion control, weed suppression, and soil health improvement. However, integrating cover crops into dryland cropping systems of the SGP faces challenges because of low quantity of soil-water availability. More research on the tradeoff between water use and other agroecosystem benefits of cover cropping is required to successfully integrate cover crops into dryland cropping systems in the SGP.

Flixweed (Descurainia sophia) Shade Tolerance and Possibilities for Flixweed Management Using Rapeseed Seeding Rate

Brassicaceae weeds can be problematic in canola varieties that have not been modified to resist specific broad-spectrum herbicides. The overall objective of this study was to evaluate the potential for increased rapeseed seeding rate as a management strategy for flixweed. To accomplish this objective, a field study was conducted to determine crop seeding rate effects on canopy light transmission and rapeseed yield characteristics, as well as a greenhouse study to determine morphological and photosynthetic responses of flixweed to decreasing irradiance levels. Results from the field study indicated that light transmittance through the canopy decreased linearly as crop seeding rate increased from 1.8 to 9.0 kg ha-1. Increasing crop seeding rate did not influence rapeseed aboveground biomass, seed yield, and harvest index, but negatively affected rapeseed seed oil content in one of two siteyears. Greenhouse study results indicated that declining irradiance levels caused reductions in flixweed biomass, root allocation, and photosynthetic light compensation point. Flixweed leaf allocation, foliage area ratio, and specific foliage area increased in response to decreasing irradiance levels. Combined results of field and greenhouse studies suggest that increasing rapeseed seeding rate can suppress flixweed growth while not causing yield penalties from increased intraspecific competition. However, increased rapeseed seeding rate might not be an adequate control strategy on its own because flixweed displays characteristics of a shade-tolerant species. Nomenclature: Flixweed, Descurainia sophia (L.) Webb. ex. Prantl; rapeseed, Brassica napus L.

Circles of live buffer strips in a center pivot to improve multiple ecosystem services and sustainability of irrigated agriculture in the southern Great Plains

Life on Earth, including that of humans, depends entirely on ecosystem services. In spite of that, in the last 50 to 60 years, human activities have degraded ecosystems more rapidly than in any comparable time in human history (MEA 2005). This is happening at a time when the global population is rapidly increasing to reach nine billion and other drivers, like climate change, overexploitation and pollution of natural resources, and economic growth, are also increasing (Carpenter 2009). Therefore, innovative ideas are needed to improve ecosystem services while increasing food production. Irrigation from the Ogallala Aquifer has converted the southern Great Plains (SGP) from a dust bowl to a highly productive agricultural region. Water from the aquifer is used to irrigate over 2.6 × 106 ha (6.5 × 106 ac) in the SGP and has supported a flourishing rural economy that includes large beef and dairy industries. The water level of the aquifer is gradually decreasing because extraction exceeds recharge. In extreme cases, the water level has declined up to 84 m (277 ft) below predevelopment levels (McGuire 2007). Because of overexploitation of the Ogallala Aquifer, 35% of the irrigated acreage is expected to be rainfed in a few decades (Scanlon…