Diseases and health complications caused by mineral deficiencies afflict billions of people globally. Developing pulse crops with elevated seed mineral concentrations can contribute to reducing the incidence of these ...
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Diseases and health complications caused by mineral deficiencies afflict billions of people globally. Developing pulse crops with elevated seed mineral concentrations can contribute to reducing the incidence of these deficiencies. The objectives of this study were to estimate variance components conditioning seed mineral concentrations of chickpea and lentil grown in Washington and Idaho, determine correlations between different mineral concentrations and between mineral concentrations and yield, 100-seed weight, and days to flowering, and compare seed mineral concentrations between chickpeas and lentils grown in adjacent plots. Genotype effects, although significant in chickpea and lentil for all minerals except selenium, tended to be minimal compared to location, year, and their interaction effects. In both chickpeas and lentils high positive correlations were observed between seed concentrations of phosphorus and potassium, phosphorus and zinc, and potassium and zinc. Correlations between mineral concentration and yield, and mineral concentration and days to 50% flowering were similar for chickpeas and lentils across the majority of minerals. These results may reflect similarities between the two crops in physiological processes for mineral uptake and partitioning. Lentils had higher concentrations of iron and zinc than chickpea when the two crops were grown in adjacent plots,whereas chickpeas had higher concentrations of calcium and manganese. Plant genotypes that are more efficient at obtaining minerals from growing environments will be useful as parental materials to develop improved chickpea and lentil cultivars that have good yield potential coupled with high seed mineral concentrations.
Biochars can improve soil health but have been widely shown to reduce plant-available nitrogen(N)owing to their high carbon(C)content,which stimulates microbial N-immobilization.However,because biochars contain large ...
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Biochars can improve soil health but have been widely shown to reduce plant-available nitrogen(N)owing to their high carbon(C)content,which stimulates microbial N-immobilization.However,because biochars contain large amounts of C that are not microbially available,their total elemental C:N ratio does not correspond well with impacts on soil N.We hypothesized that impacts on soil plant-available N would relate to biochar mineralizable-C(C_(min))content,and that C:N ratios of the mineralizable biochar component could provide a means for predicting conditions of net soil N-mineralization or-immobilization.We conducted two laboratory experiments,the first measuring biochar C_(min)from respiration of isotopically labeled barley biochars manufactured at 300,500,and 750℃,and the second characterizing C_(min)by proxy measurements for ten biochars from six feedstocks at several temperatures.For both experiments,soils were incubated with 2%biochar by mass to determine impacts to soil N-mineralization.Contrary to expectation,all the biochars increased soil N-mineralization relative to unamended soils.Also unexpected,higher temperature(500 and 700℃)barley biochars with less C_(min)stimulated more soil decomposition and more soil N-mineralization than a 350℃barley biochar.However,across diverse biochar feedstocks and production methods,none of the biochar characteristics correlated with soil N-mineralization.The finding of improved soil N-mineralization adds complexity to the range of soil N responses that can be expected in response to biochar amendment.Because of the limited ability to predict soil N responses from biochar properties,users should monitor soil N to manage soil fertility.
The emergence of the tracheophyte-based vascular system of land plants had major impacts on the evolution of terrestrial biology, in general, through its role in facilitating the development of plants with increased s...
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The emergence of the tracheophyte-based vascular system of land plants had major impacts on the evolution of terrestrial biology, in general, through its role in facilitating the development of plants with increased stature, photosynthetic output, and ability to colonize a greatly expanded range of environmental habitats. Recently, considerable progress has been made in terms of our understanding of the developmental and physiological programs involved in the formation and function of the plant vascular system. In this review, we first examine the evolutionary events that gave rise to the tracheophytes, followed by analysis of the genetic and hormonal networks that cooperate to orchestrate vascular development in the gymnosperms and angiosperms. The two essentialfunctions performed by the vascular system, namely the delivery of resources (water, essential mineral nutrients, sugars and amino acids) to the various plant organs and provision of mechanical support are next discussed. Here, we focus on critical questions relating to structural and physiological properties controlling the delivery of material through the xylem and phloem. Recent discoveries into the role of the vascular system as an effective long-distance communication system are next assessed in terms of the coordination of developmental, physiological and defense-related processes, at the whole-plant level. A concerted effort has been made to integrate all these new findings into a comprehensive picture of the state-of-the-art in the area of plant vascular biology. Finally, areas important for future research are highlighted in terms of their likely contribution both to basic knowledge and applications to primary industry.
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