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Dry Matter Accumulation (dry + matter_accumulation)
Selected AbstractsEffects of Nitrogen on Dry Matter Accumulation and Productivity of Three Cropping Systems and Residual Effects on Wheat in Deep Vertisols of Central IndiaJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 2 2002P. Ramesh A field experiment was conducted on deep vertisols of Bhopal, India to study the effects of three levels of nitrogen (N), namely 0, 75 and 100 % of the recommended dose of nitrogen (RDN), on the dry matter accumulation (DMA) and productivity of three cropping systems (sole soybean, sole sorghum and soybean + sorghum intercropping) during the rainy season and their residual effect on the subsequent wheat crop during the post-rainy season. During the rainy season, sole sorghum was found to have significantly higher DMA and productivity in terms of soybean equivalent yield (SEY) than sole soybean or soybean + sorghum intercropping. Increasing the N dose from 0 to 100 % RDN significantly improved the DMA and SEY. At a low fertility level (N0), soybean + sorghum intercropping was found to be more productive, while at a high fertility level (100 % RDN), sole sorghum was more productive than the other two cropping systems. However, during the post-rainy season, sole soybean as the preceding crop gave the highest DMA and seed yield of wheat, which were similar to those found with soybean + sorghum intercropping. Sorghum followed by wheat gave the lowest DMA and seed yield of wheat. Application of 100 % RDN irrespective of cropping system during the preceding crop improved the DMA of wheat but not its seed yield. However, N applied to the wheat crop significantly increased its DMA and seed yield. Einfluss von Stickstoff auf Trockenmasseakkumulation und Produktivität von drei Anbausystemen und deren Rückstandswirkung auf Weizen in einem tiefen Vertisol Zentralindiens Ein Feldexperiment wurde durchgeführt auf einem tiefen Vertisol bei Bhopal, Indien, um den Einfluss von drei Stickstoffkonzentrationen 0, 75 und 100 % der empfohlenen Stickstoffmenge (RDN) auf die Trockenmasseakkumulation (DMA) und Produktivität von drei Anbausystemen (Reinanbau Sojabohne, Reinanbau Sorghum und Sojabohne + Sorghum Mischanbau) während der Regensaison und deren Nachwirkungen auf den folgenden Anbau von Weizen während der Nachregensaison zu untersuchen. Während der Regensaison war der Reinanbau von Sorghum signifikant höher in DMA und in der Produktivität in Form von Ertragsäquivalenten für Sojabohnen (SEY) im Vergleich zu einem Reinanbau von Sojabohne oder einem Mischanbau von Sojabohne + Sorghum. Eine Erhöhung der N-Anwendung von 0 bis 100 % RDN erhöhte Signifikanz DMA und SEY. Unter der niedrigen Düngung (N0) erwies sich Sojabohne + Sorghum Mischanbau als produktiver im Vergleich zu einer hohen Düngungeranwendung (100 % RDN), Reinanbau war produktiver als die anderen beiden Anbausysteme. Allerdings während der Nachregensaison erwies sich der Reinanbau von Sojabohnen vor Weizen als die höchste DMA und Ertragsmenge, was mit dem Sojabohnen + Sorghum Mischanbau vergleichbar war. Sorghum gefolgt von Weizen ergab den geringsten DMA und niedrigsten Weizenertrag. Die Anwendung von 100 % RDN erhöhte unabhängig von dem Anbausystem der vorhergehenden Kulturpflanzen DMA von Weizen aber nicht den Kornertrag. Allerdings erhöhte N im Weizenanbau signifikant sowohl DMA als auch Kornertrag. [source] Sex-specific responses of Populus cathayana to drought and elevated temperaturesPLANT CELL & ENVIRONMENT, Issue 6 2008XIAO XU ABSTRACT Dioecious plant species represent an important component of terrestrial ecosystems. Yet, little is known about sex-specific responses to drought and elevated temperatures. Populus cathayana Rehd, which is a dioecious, deciduous tree species, widely distributed in the northern, central and southwestern regions of China, was employed as a model species in our study. In closed-top chamber experiments, sex-specific morphological, physiological and biochemical responses of P. cathayana to drought and different elevated temperatures were investigated. Compared with the controls, drought significantly decreased the growth and the net photosynthesis rate (A), and increased the intrinsic water use efficiency (WUEi), carbon isotope composition (,13C), and the malondialdehyde (MDA) and abscisic acid (ABA) contents in droughted plants. In contrast, elevated temperatures significantly promoted the growth and the A, but decreased the WUEi, ,13C, MDA and ABA contents in well-watered individuals. When compared with males, elevated temperatures induced well-watered females to express a greater increase in the height growth (HG), basal diameter (BD), leaf area (LA), total number of leaves (TNL), dry matter accumulation (DMA) and specific leaf area (SLA), and a lower decrease in the A value, transpiration (E), stomatal conductance (gs), MDA and ABA contents, while elevated temperatures induced drought-stressed females to exhibit lower values of HG, BD, LA, TNL, DMA, A, E, gs and the intercellular CO2 concentration (Ci), and higher levels of SLA, WUEi, ,13C, MDA and ABA contents. Our results indicated that the female individuals of P. cathayana are more responsive and suffer from greater negative effects than do males when grown under environments with increased drought stress and elevated temperature. [source] Influence of minisett sizes on dry matter accumulation and fresh tuber yield of white Guinea yam (Dioscorea rotundata)ANNALS OF APPLIED BIOLOGY, Issue 2 2009K.E. Law-Ogbomo Abstract Studies were conducted in 2005 and 2006 at Irrua, Nigeria, to determine the performance of various sizes of minisetts of Dioscorea rotundata cv. ,Obiaoturugo' evaluated for size and yield of yield matter and seed yams. These trials involved a macrosett (250 g) and six minisett sizes (25, 30, 35, 40, 45 and 50 g) in a randomised block design with four replicates. The results indicated that larger minisetts had higher degree of field establishment, foliation, leaf area index, total dry weight, percentage of leaf dry matter and net assimilation rate. These growth parameters influenced higher crop growth rate, which was responsible for higher fresh tuber yield. The macrosett's fresh tuber yield was the greatest (20.48 t ha,1) but had the least multiplication ratio (8.19). The greatest multiplication ratio was obtained from 30-g setts. [source] Crop traits and the tolerance of wheat and barley to foliar diseaseANNALS OF APPLIED BIOLOGY, Issue 2 2009I.J. Bingham Abstract The relationship between yield loss and disease severity can differ widely between crops. This has given rise to the concept of disease tolerance, with some crops exhibiting a smaller yield loss under a given severity of disease than others. Genetic improvement to minimise yield loss under disease is an attractive goal, as it exerts little or no selection pressure on pathogen populations, and could form a useful component of durable disease management programmes. However, progress towards this end requires a thorough understanding of the phenotypic traits that influence the response of yield to disease, their genetic control and the possible trade-offs involved with other desirable agronomic characteristics. This paper examines the candidate crop traits that may confer tolerance of foliar disease in wheat and barley and reviews evidence of genetic variation in their expression. In wheat grown under the relatively low light conditions of North-West Europe, post-anthesis source (assimilate supply) and grain sink capacity (capacity for dry matter accumulation) appear to be closely balanced. Traits associated with maintaining post-anthesis radiation interception and radiation use efficiency in spite of disease may confer tolerance. The most promising traits include a larger flag leaf and compensatory increases in photosynthetic rate in non-infected parts of leaves. In barley, yield is often more strongly sink limited, and early-season disease management is required to protect the formation of potential grain sites. A wider range of potential traits may influence tolerance including compensatory adjustments in leaf growth and morphology, and differences in the sensitivity of tiller and spikelet mortality to photoassimilate supply. Different methods for quantifying tolerance are suggested depending on the trait of interest. [source] Protein and oil concentration of soybean seed cultured in vitro using nutrient solutions of differing glutamine concentrationANNALS OF APPLIED BIOLOGY, Issue 2 2004ANTONIO E PIPOLO Summary Oil and protein are the most valuable components of soybean seed. Evidence indicates that growth and composition of soybean seed are controlled by supplies of carbon and nitrogen provided by the maternal plant to the seed, but it is difficult experimentally to control and quantify the precise amount of carbon and nitrogen provided to the seed by the whole plant. To examine whether oil and protein concentrations are affected by the supply of nitrogen to the seed, immature soybean seeds (Glycine max cv. Williams 82) were grown in vitro in nutrient solutions containing 20, 40, 60 or 80 mM of glutamine. The seeds were incubated in Erlenmeyer flasks for 8 days at 25°C. The rate of dry matter accumulation changed from 7.2 to 8.3 mg seed,1 day,1 as the glutamine concentration increased from 20 to 80 mM but the differences were not significant (P 0.05). Seed protein concentration increased as glutamine concentration increased from 294 mg g,1 at 20 mM glutamine to as high as 445 mg g,1 at 80 mM glutamine. Typical in vivo protein concentration of mature soybean seeds is about 400 mg g,1. Oil and protein concentrations were negatively correlated (r2= 0.44), which indicates that oil and protein synthesis are interrelated. Protein synthesis was favoured over oil synthesis when nitrogen became more abundant. The seeds used in this study clearly demonstrated a capacity to respond to nitrogen availability with changes in seed protein concentration. [source] | ||||||||||