Preliminary Report, Soybean Performance Tests - 1971

The data presented below represent the preliminary results of the 1971 Soybean Performance Tests. A more complete version of the data, including data from previous years, will be published at a later date in Results of the Kentucky Soybean Performance Tests - 1971

York Soybeans Added to Recommended List

York soybean, a pure line selection developed by the Virginia Agricultural Experiment Station from a cross of Dorman X Hood, was recently added to the recommended list for Kentucky. It was released jointly in 1967 by Virginia, Maryland, and North Carolina

Preliminary Report Soybean Performance Tests 1970

The data presented below represent the preliminary results of the 1970 Soybean Performance Tests . A more complete version of the data, including data from previous years , will be published at a later date in Results of the Kentucky Soybean Performance Tests - 1970

Seed Biology and Yield of Grain Crops

Description from CABI (Centre for Agriculture and Biosciences International): This new edition of an established title examines the determination of grain crop yield from a unique perspective, by concentrating on the influence of the seed itself. As the food supply for an expanding world population is based on grain crops harvested for their seeds, understanding the process of seed growth and its regulation is crucial to our efforts to increase production and meet the needs of that population. Yield of grain crops is determined by their assimilatory processes such as photosynthesis and the biosynthetic processes in the seed, which are partly regulated within the seed itself. Providing a timely update in this field and highlighting the impact of the seed on grain crop yields, this book: Describes all aspects of seed growth and development, including environmental and genetic effects on growth rate and length of the filling period. Discusses the role of the seed in determining the two main yield components: individual seed weight and number of seeds per unit area. Uses the concepts and models that have been developed to understand crop management and yield improvement. Substantially updated with new research and further developments of the practical applications of the concepts explored, this book is essential reading for those concerned with seed science and crop yield, including agronomists, crop physiologists, plant breeders, and extension workers. It is also a valuable source of information for lecturers and graduate students of agronomy and plant physiology.https://uknowledge.uky.edu/pss_book/1005/thumbnail.jp

The Influence of Soil Temperature on Soybean Seed Emergence

The best way to obtain adequate soybean stands is to plant high quality seed in an optimum soil environment. But this year many farmers may not be able to obtain enough high quality soybean seed and some acreage may be planted with seed of lower than normal quality. Thus it will be even more important to have an optimum soil environment

Foliar Fertilization of Soybeans

Research reported by Iowa State University during the winter of 1975-76 suggested that a means of increasing soybean yields by use of a specific foliar fertilizer had been demonstrated (1976). Theory proposed to explain the reported responses was as follows: Up to the seed filling period in soybean growth, soybean roots and activity of nitrogen-fixing bacteria contained in root nodules are capable of supplying the necessary nutrients to meet the plants demands. However, as seed filling begins root growth stops and nodule activity declines. This results in nutrients being redistributed from leaves to seeds and a reduction in rate of photosynthesis. Consequently, studies were conducted to evaluate methods of foliar fertilization in an attempt to maintain photosynthetic rate and nutrient supply during seed filling, the objective being to increase yields

An Early-Planted, Early Maturing Soybean Cropping System: Yield and Harvest Losses

Most soybean varieties used In Kentucky, whether grown full season or double-cropped behind wheat or barley, are from Maturity Groups (MG) IV or V. Some MG III varieties are also grown; however, virtually no MG 1/ or earner varieties are planted. Agronomists and soybean producers in Kentucky· have generally felt that MG IV and V varieties produce the highest yield. Since the driest months in Kentucky are August, September,and October, MG IV and V varieties frequently encounter moisture stress during the important seed fill stage. The use of earlier maturing varieties was initially proposed as a means of getting a major portion of seed fill to occur before the driest part of the growing season, thus getting higher yields in dry years

Foliar Fertilization of Soybeans - 1977

Field investigations on the effect of foliar fertilization were continued on soybeans during 1977. Results from our 1976 studies have previously been published. In 1976 we tested a material produced by TVA. We used the same TVA-material in 1977 and in addition, included a commercially available product (Foliantm, manufactured by Allied Chemical Corporation)

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Seed Biology and the Yield of Grain Crops/ Egli

ix, 178 hal.: ill.; 24 cm