Horticulture Commons^™

Functional Divergence Of Diterpene Syntheses In The Medicinal Plant Salvia Miltiorrhiza, Guanghong Cui, Lixin Duan, Baolong Jin, Jun Qian, Zheyong Xue, Guoan Shen, John Hugh Snyder, Jingyuan Song, Shilin Chen, Luqi Huang, Reuben J. Peters, Xiaoquan Qi

Reuben J. Peters

The medicinal plant Salvia miltiorrhiza produces various tanshinone diterpenoids that have pharmacological activities such as vasorelaxation, against ischemia-reperfusion injury, and antiarrhythmic effects. Their biosynthesis is initiated from the general diterpenoid precursor (E,E,E)-geranylgeranyl diphosphate by sequential reactions catalyzed by copalyl diphosphate synthase (CPS) and kaurene synthase-like (KSL) cyclases. Here is reported characterization of these enzymatic families from S. miltiorrhiza, which has led to the identification of novel pathways, including roles for separate CPSs in tanshinone production in roots versus aerial tissues (SmCPS1 and SmCPS2, respectively), as well as the novel production of ent-13-epi-manoyl oxide by SmCPS4 and SmKSL2 ...

Integration Of Natural Seed Treatments In Organic And Open-Pollinated Corn Systems, A. Susana Goggi, Kathleen Delate, Linda M. Pollak, Kendall R. Lamkey

Kendall R Lamkey

Essential oils from the aromatic plants, such as thyme, oregano, cinnamon, clove, and savory, were used to effectively control several common seed and soil pathogens in the laboratory, and could be used as seed treatments in corn. Results from field experiments showed some oils protected the seeds from pathogens but not others. Before these natural products can be widely adopted, however, issues of volatility of the oils at ambient temperature and appropriate application rate must be addressed.

Mycorrhizae And Phosphorus Nutrition Of Pine Seedlings In A Prairie Soil Nursery, A. L. Mccomb

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The relation of the mycorrhizal soil fungi to the growth of conifers has long been a controversial subject.³ Recent experiments in nursery production, in afforestation and in extending the range of certain species of conifers (11, 14, 21, 32, 36, 37, 38) have reemphasized the importance of these fungi in promoting tree growth and aiding nutrition. Nonetheless, the manner in which these organisms work is still obscure, and growth stimulation of seedlings has been attributed both to effects resulting from the invasion of short roots by fungi and to the activity of the fungus in the soil adjacent to ...

Function And Biodegradation In Soil Of Bioplastic Horticultural Containers Made Of Pla-Biorestm Composites, James Schrader, Kenneth Mccabe, William Graves, David Grewell

David A. Grewell

Container-crops horticultural industries rely almost exclusively on petroleum-based plastic containers for modern production systems. Containers made of these materials fulfill all of the functions required during crop production, and perform better than containers made of clay, peat, and other natural materials, but the source of the plastic materials (fossil carbon), their lack of biodegradability, and their end-of-life disposal (97% end up in landfills) are major obstacles to sustainability. Although function and efficiency are among the most important aspects in determining the best materials for horticultural containers, there is no need for containers to persist in the environment for decades when ...

Growth And Flowering Of The Gladiolus Influence Of Certain Morphological And Physiological Characteristics Of The Corms, L. C. Grove

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Experiments were conducted for two seasons to determine the growth and flowering abilities of high and low crowned gladiolus corms of nine varieties distributed among the primulinus, grandiflorus and primulinus grandiflorus types. Chemical analyses were run on high and low crowned mother corms of the variety Excellence grown in the field and in the darkness, to determine whether any differences in sugars, polysaccharides and nitrogen might be associated with any differences in growth and flowering. Samples were taken at several stages of growth and during two seasons.

A Study Of Drouth Resistance In Inbred Strains Of Sweet Corn Zea Mays Var. Rugosa, E. S. Haber

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Plant breeders have noted that corn inbreds and hybrids shovv marked differences in their ability to withstand even mild periods of drouth and high temperatures. Sweet corn inbreds and hybrids as a group do not have as high resistance as field corn in breds and hybrids. The most resistant sweet corn lines are not equal to the most resistant field corn lines.

Since 1929, in central Iowa, it has been comparatively easy to classify sweet corn inbreds in the field according to their relative resistance. Less than normal rainfall and higher than normal temperatures during a part of the growing ...

Regeneration In Various Types Of Apple Wood, V. T. Stoutemyer

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Two distinct growth phases were demonstrated to exist in apple trees. These phases were closely related to the ease of regeneration of roots on stems. Stem cuttings of wood in the mature phase were very difficult to root without special treatments, while those made from shoots in the juvenile phase rooted very readily.

The juvenile condition was recognized by the thinness of the leaves and small amount of pubescence. Anthocyanin production was abundant in juvenile shoots. In some species of apple the shape of the leaf changed with maturity from an entire to a lobed form.

Shoots having the juvenile ...

Effects Of Tillage And Cover Cropson Muskmelon Production And Food Safety, John Krzton-Presson, Ajay Nair, Angela Shaw

Angela M. Shaw

Reduced tillage has been widely adopted in production of agronomic crops for its potential to improve soil health and reduce input costs. Despite this, vegetable growers largely rely on conventional tillage (CT) to incorporate crop residue, control weeds, and prepare a loose seed bed for planting. Conventional tillage may cause reduced water infiltration, lessen soil biodiversity, and increase nitrate leaching, erosion and weed germination. Strip-tillage (ST) only disturbs the soil in a 12-in. strip where the cash crop will be planted, leaving the rest of the field untilled.

Influence Of Uv Treatment On The Food Safety Status Of A Model Aquaponic System, Sai Deepikaa Elumalai, Angela M. Shaw, D. Allen Pattillo, Christopher J. Currey, Kurt A. Rosentrater, Kun Xie

Angela M. Shaw

Few microbial studies in aquaponics, a growing trend in food production, have been conducted to determine food safety status. The aim of this study was to determine the food safety status and the effectiveness of ultraviolet treatment (15 W, luminous flux of 900 lm) as a food safety intervention in reducing the microbial loads of the water system in a model aquaponic unit growing lettuce, basil, and barramundi (Australian Sea Bass). Sweet basil, bibb lettuce, water samples, and fish swabs were collected throughout the 118-day production period, and microbial analysis was conducted in triplicate for the presence of E. coli ...

Growth Responses Of The Gladiolus As Influenced By Storage Temperatures, David C. Fairburn

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The gladiolus, one of the most popular ornamental bulbous plants, is a tender perennial and will not survive if exposed to severe winter weather. The corms must be removed from the garden in the fall and stored until planting time in the spring. The conditions to which the corms are subjected during storage determine to a large extent the growth responses the following season. Consequently, this phase of gladiolus culture is of paramount importance. The present knowledge regarding proper storage temperatures is far from comprehensive. Further study is necessary, and the following investigation concerned with the physiology, morphology and growth ...

Transcriptomic Resources For The Medicinal Legume Mucuna Pruriens: De Novo Transcriptome Assembly, Annotation, Identification And Validation Of Est-Ssr Markers, N. Sathyanarayana, Ranjith Kumar Pittala, Pankaj Kumar Tripathi, Ratan Chopra, Heikham Russiachand Singh, Vikas Belamkar, Pardeep Kumar Bhardwaj, Jeff J. Doyle, Ashley N. Egan

Agronomy & Horticulture -- Faculty Publications

Background:

The medicinal legume Mucuna pruriens (L.) DC. has attracted attention worldwide as a source of the anti-Parkinson’s drug L-Dopa. It is also a popular green manure cover crop that offers many agronomic benefits including high protein content, nitrogen fixation and soil nutrients. The plant currently lacks genomic resources and there is limited knowledge on gene expression, metabolic pathways, and genetics of secondary metabolite production. Here, we present transcriptomic resources for M. pruriens, including a de novo transcriptome assembly and annotation, as well as differential transcript expression analyses between root, leaf, and pod tissues. We also develop microsatellite markers ...

A Comprehensive Analysis Of Alternative Splicing In Paleopolyploid Maize, Wenbin Mei, Sanzhen Liu, James C. Schnable, Cheng-Ting Yeh, Nathan M. Springer, Patrick S. Schnable, William Brad Barbazuk

Agronomy & Horticulture -- Faculty Publications

Identifying and characterizing alternative splicing (AS) enables our understanding of the biological role of transcript isoform diversity. This study describes the use of publicly available RNA-Seq data to identify and characterize the global diversity of AS isoforms in maize using the inbred lines B73 and Mo17, and a related species, sorghum. Identification and characterization of AS within maize tissues revealed that genes expressed in seed exhibit the largest differential AS relative to other tissues examined. Additionally, differences in AS between the two genotypes B73 and Mo17 are greatest within genes expressed in seed. We demonstrate that changes in the level ...

Patch Seeding On An Extensive Green Roof: Initial Experiment On Microclimate Impacts, Zhuqing Xu

Theses, Dissertations, and Student Research in Agronomy and Horticulture

The green roof provides not only aesthetic values but also many ecological benefits. In North America, seeding or reseeding with native species becomes increasingly popular as a result of its high efficacy and low cost. The extreme temperature and a lack of water on the green roof impose restrictions on seeds germination that determines the success of a seeding program.

The study started on June 1 and was completed by July 15. Five Great Plains native species were hand-seeded in two blocks on Larson Building green roof, along with two blocks set up in the greenhouse at University of Nebraska-Lincoln ...

Phenotypic Variation And Genetic Purity Of The Original 'Prime-Jim®' X 'Arapaho' Population, Loren M. Luther

Horticulture Undergraduate Honors Theses

In 2013, Castro et al., produced the first linkage map for primocane-fruiting blackberries using the cross ‘Prime-Jim®’ x ‘Arapaho.’ This mapping population has been maintained since the original experiment with the hopes of conducting future studies. Further research was determined to be needed on the population to better characterize additional phenotypic traits, and since nine years had passed since the seedlings were established, there was a need to assess the continued genetic purity of the population using molecular methods. Phenotypic data was collected to analyze the variation of the population including soluble solids content, titratable acidity, average weight, shape, and ...

Evaluation And Association Analysis Of Cowpea Salt Tolerance, Waltram Second Ravelombola

Theses and Dissertations

Cowpea [Vigna unguiculata (L.) Walp.] (2n=2x=22) is a leguminous crop providing inexpensive protein for human consumption that can be grown worldwide. Salinity is one of the major threats to cowpea production, particularly in semi-arid regions of Africa. Salinity significantly affects seed germination and decreases pod yield in cowpea. However, little has been done to provide farmers salt-tolerant cowpea cultivars. Knowledge on the genetics of cowpea salt tolerance is very limited. This study aimed to:(1) evaluate cowpea salt tolerance at germination stage, (2) evaluate cowpea salt tolerance at seedling stage, (3) conduct an association study for cowpea salt ...

Value Of Cover Crops In Suppressing Weeds And Protecting Cotton Yields And Likelihood Of Residual Herbicide Carryover To Cover Crops, Matheus Gabriel Palhano

Theses and Dissertations

Weed-resistance management has become a topic of concern for modern agriculture. Cost related to herbicide usage has increased greatly due to evolution and proliferation of resistant weeds. Therefore, experiments were conducted to investigate the potential for using cover crops to suppress problematic weeds in cotton as well as chemical options for cover crop dessication, and sensitivity of cover crops to residual herbicides were evaluated. No differences were observed for cereal rye biomass production and consequently weed suppression between broadcast and drilled planting methods. Total amount of cover crop biomass was vital to effectively suppress weeds. Hence, of the cover crops ...

Effects Of Cover Crop Treatments On Apple Trees, Jennifer Billig

Theses and Dissertations

Ground cover management systems affect soil quality and health and thereby orchard growth and productivity. There have been few studies in the southern US on the effects of managed drive-rows using cover crops as part of a sustainable apple orchard management system. A field study used treatments of 1) seasonal legumes (cowpea [Vigna unguiculata] and crimson clover [Trifolium incarnatum]), 2) seasonal grasses (millet [Setaria italic] and annual rye [Lolium multiflorum]), or 3) unmanaged natural vegetation drive row plantings, with mowed vegetation blown into the tree row as mulch (mow/blow) nested variable. The legume crop cycles produced more than twice ...

Environmental And Climatic Constraints On Large-Scale Camelina Production In Eastern Arkansas, Benjamin Robert Tracy

Theses and Dissertations

Camelina sativa is a cold weather crop that is typically grown in semi-arid environments in the Western United States, usually as a spring crop, but sometimes during the winter. Research analyzing climate data and soil hydrology is important to better understand the environmental and terrain conditions necessary for Camelina farming wherever it is proposed for large-scale production. This study focused on various conditions and constraints pertaining to the potential for Camelina as a crop biofuel in Eastern Arkansas. Due to interest in the economic potential of crop biofuels in this area, and in particular the low input costs for Camelina ...

Chinese Forestry - Relationships Worth Cultivating, Mark P. Widrlechner

Mark P. Widrlechner

From 10 September to 1 October 1995, I participated in a cooperative technical exchange program in China, co-sponsored by the U.S, Department of Agriculture and the Chinese Ministry of Forestry. The goals of this trip were to share expertise and to acquire cold-hardy germplasm of disease-resistant elms (Ulmus L.), especially focusing on Ulmus parvifolia Jacq., the lacebark elm. The U.S. team was led by Dr. Eugene Smalley, of the University of Wisconsin-Madison, and included: Mrs. Joan Smalley; Drs. Raymond Guries and Weidong Wu, also of the University of Wisconsin; and Dr. George Ware, of the Morton Arboretum. Visits ...

North American Continent - A New Source Of Wild Lactuca Spp. Germplasm Variability For Future Lettuce Breeding, A. Lebeda, I. Doležalová, M. Kitner, A. Novotná, P. Šmachová, M. P. Widrlechner

Mark P. Widrlechner

In the years 2002-2008, missions were undertaken in the USA and Canada to search for wild and weedy Lactuca species. Altogether, 16 states in the USA (Arizona, California, Colorado, Idaho, Iowa, Minnesota, Montana, Nevada, New York, North Carolina, Oregon, South Dakota, Utah, Washington, Wisconsin and Wyoming) and two provinces in Canada (Ontario and Quebec) were visited. In total, seven wild and weedy Lactuca spp. (L. serriola, L. saligna, L. virosa, L. canadensis, L. biennis, L. floridana, and L. ludoviciana), an interspecific hybrid (L. canadensis × L. ludoviciana), and an undetermined Lactuca species were observed and collected in 200 locations. In this ...