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In strategic marketing decisions substantial emphasis is placed on market segmentation and product/service differentiation. This follows from separate, intensive analyses of customers and competitors. Based on these analyses, the resultant segmentation and differentiation schema, and an intensive review of the firm's own strengths, weaknesses, opportunities and threats, the firm makes one of its most important and critical decisions: which customers to serve and which products to emphasize, referred to as positioning. On the other side of the same corporate coin, manufacturing makes decisions on process and infrastructure investments based upon the technologies required, and its perception of what it needs to do well in order to fulfil its role. In the same way as with marketing decisions, the firm now makes another of its most critical decisions by committing itself to major investments in manufacturing that are characterized by high value and long time scales to change. On the one hand, these positioning decisions by marketing invariably include little emphasis in determining the customer requirements that must be supported by manufacturing, and fail to investigate the ability of manufacturing to support these requirements. On the other hand, manufacturing decisions do not reflect key insights on the needs of current and future markets. As a consequence, many businesses fail to achieve their strategic business objectives, due, in part, to the inability of marketing and manufacturing to jointly develop consistent strategies. We call this a lack of alignment. The methodology outlined in this paper concerns how to align marketing and manufacturing strategies by using markets as the center piece of both developments. Doing this highlights the recognition that markets need to form the common denominator of both marketing and manufacturing strategy development. This methodology is illustrated by using an actual example drawn from plant-based research. Several ke... [ABSTRACT FROM AUTHOR]

Background Agriculture is the single largest geo-engineering initiative that humans have initiated on planet Earth, largely through the introduction of unprecedented amounts of reactive nitrogen (N) into ecosystems. A major portion of this reactive N applied as fertilizer leaks into the environment in massive amounts, with cascading negative effects on ecosystem health and function. Natural ecosystems utilize many of the multiple pathways in the N cycle to regulate N flow. In contrast, the massive amounts of N currently applied to agricultural systems cycle primarily through the nitrification pathway, a single inefficient route that channels much of this reactive N into the environment. This is largely due to the rapid nitrifying soil environment of present-day agricultural systems. Scope In this Viewpoint paper, the importance of regulating nitrification as a strategy to minimize N leakage and to improve N-use efficiency (NUE) in agricultural systems is highlighted. The ability to suppress soil nitrification by the release of nitrification inhibitors from plant roots is termed ‘biological nitrification inhibition’ (BNI), an active plant-mediated natural function that can limit the amount of N cycling via the nitrification pathway. The development of a bioassay using luminescent Nitrosomonas to quantify nitrification inhibitory activity from roots has facilitated the characterization of BNI function. Release of BNIs from roots is a tightly regulated physiological process, with extensive genetic variability found in selected crops and pasture grasses. Here, the current status of understanding of the BNI function is reviewed using Brachiaria forage grasses, wheat and sorghum to illustrate how BNI function can be utilized for achieving low-nitrifying agricultural systems. A fundamental shift towards ammonium (NH4+)-dominated agricultural systems could be achieved by using crops and pastures with high BNI capacities. When viewed from an agricultural and environmental perspective, the BNI function in plants could potentially have a large influence on biogeochemical cycling and closure of the N loop in crop–livestock systems. [ABSTRACT FROM AUTHOR]

Nitrification, a key process in the global nitrogen cycle that generates nitrate through microbial activity. may enhance losses of fertilizer nitrogen by leaching and denitrification. Certain plants can suppress soil-nitrification by releasing inhibitors from roots, a phenomenon termed biological nitrification inhibition (BNI). Here, we report the discovery of an effective nitrification inhibitor in the root-exudates of the tropical forage grass Brachiaria humidicola (Rendle) Schweick. Named "brachialactone," this inhibitor is a recently discovered cyclic diterpene with a unique 5-8-5-membered ring system and a y-lactone ring. It contributed 60-90% of the inhibitory activity released from the roots of this tropical grass. Unlike nitrapyrin (a synthetic nitrification inhibitor), which affects only the ammonia monooxygenase (AMO) pathway, brachialactone appears to block both AMO and hydroxylamine oxidoreductase enzymatic pathways in Nitrosomonas. Release of this inhibitor is a regulated plant function, triggered and sustained by the availability of ammonium (NH+4) in the root environment. Brachialactone release is restricted to those roots that are directly exposed to NHL Within 3 years of establishment, Brachiaria pastures have suppressed soil nitrifier populations (determined as amoA genes; ammonia-oxidizing bacteria and ammonia-oxidizing archaea), along with nitrification and nitrous oxide emissions. These findings provide direct evidence for the existence and active regulation of a nitrification inhibitor (or inhibitors) release from tropical pasture root systems. Exploiting the BNI function could become a powerful strategy toward the development of low-nitrifying agronomic systems, benefiting both agriculture and the environment. [ABSTRACT FROM AUTHOR]

The tropical pasture grass, Brachiaria humidicola (Rendle) Schweick, produces nitrification inhibitory compounds (termed biological nitrification inhibitors or BNIs) in its shoot and root tissues and releases BNIs from its roots. In the present study, two BNI compounds were isolated and identified from the shoot tissue of B. humidicola using activity-guided fractionation. The recombinant Nitrosomonas europaea containing luxAB genes derived from the bioluminescent marine gram-negative bacterium Vibrio harveyi, were used to determine BNI activity. The BNI compounds in the shoot tissue were identified as linoleic acid (LA) and linolenic acid (LN) using authentic-chemicals obtained from ©Sigma (ED80 16.0 μg ml−1 for both LA and LN) for verification. None of the other tested free fatty acids namely stearic acid, oleic acid, arachidonic acid, and cis-vaccenic acid showed any inhibitory effect on nitrification. Among the fatty acid methyl esters (FAME) evaluated [methyl oleate, methyl linoleate (LA-ME) and methyl linoleneate (LN-ME)], only LA-ME showed an inhibitory effect (ED80 8.0 μg ml−1). The inhibitory effect of LA, LN and LA-ME in the soil was stable for 120 days at 20°C. Soil treated with LA, LN and LA-ME showed a very low accumulation of NO3 − and the maintenance of soil inorganic N in the NH4 + form. The inhibitory effect of LA-ME on soil nitrification was greater than that of LA or LN. In addition to BNI activity, both LA and LA-ME showed a suppressive effect on urea hydrolysis in soil. Both LA and LN blocked the AMO (ammonia monooxygenase) and HAO (hydroxylamino oxidoreductase) enzymatic pathways in Nitrosomonas. Since LA and LN can be produced from vegetable oils such as soybean, flax or sunflower, they have the potential for use as nitrification inhibitors in production agriculture. [ABSTRACT FROM AUTHOR]

Using a recombinant luminescent Nitrosomonas europaea assay to quantify biological nitrification inhibition (BNI), we found that a wild relative of wheat ( Leymus racemosus (Lam.) Tzvelev) had a high BNI capacity and releases about 20 times more BNI compounds (about 30 ATU g−1 root dry weight 24 h−1) than Triticum aestivum L. (cultivated wheat). The root exudate from cultivated wheat has no inhibitory effect on nitrification when applied to soil; however, the root exudate from L. racemous suppressed $$ {\text{NO}}^{ - }_{3} $$ formation and kept more than 90% of the soil’s inorganic-N in the $$ {\text{NH}}^{ + }_{4} $$ -form for 60 days. The high-BNI capacity of L. racemosus is mostly associated with chromosome Lr#n. Two other chromosomes Lr#J, and Lr#I also have an influence on BNI production. Tolerance of L. racemosus to $$ {\text{NH}}^{ + }_{4} $$ is controlled by chromosome 7Lr#1-1. Sustained release of BNI compounds occurred only in the presence of $$ {\text{NH}}^{ + }_{4} $$ in the root environment. Given the level of BNI production expressed in DALr#n and assuming normal plant growth, we estimated that nearly 87,500,000 ATU of BNI activity ha−1 day−1 could be released in a field of vigorously growing wheat; this amounts to the equivalent of the inhibitory effect from the application of 52.5 g of the synthetic nitrification inhibitor nitrapyrin (one AT unit of BNI activity is equivalent to 0.6 μg of nitrapyrin). At this rate of BNI production it would take only 19 days for a BNI-enabled wheat crop to produce the inhibitory power of a standard commercial application of nitrapyrin, 1 kg ha−1. The synthetic nitrification inhibitor, dicyandiamide, blocked specifically the AMO (ammonia monooxygenase) pathway, while the BNI from L. racemosus blocked the HAO (hydroxylamine oxidoreductase) pathway in Nitrosomonas. Here we report the first finding of high production of BNI in a wild relative of any cereal and its successful introduction and expression in cultivated wheat. These results demonstrate the potential for empowering the new generation of wheat cultivars with high-BNI capacity to control nitrification in wheat-production systems. [ABSTRACT FROM AUTHOR]

Regulating nitrification could be a key strategy in improving nitrogen (N) recovery and agronomic N-use efficiency in situations where the loss of N following nitrification is significant. A highly sensitive bioassay using recombinant luminescent Nitrosomonas europaea, has been developed that can detect and quantify the amount of nitrification inhibitors produced by plants (hereafter referred to as BNI activity). A number of species including tropical and temperate pastures, cereals and legumes were tested for BNI in their root exudate. There was a wide range in BNI capacity among the 18 species tested; specific BNI (AT units activity g−1 root dry wt) ranged from 0 (i.e. no detectable activity) to 18.3 AT units. Among the tested cereal and legume crops, sorghum [ Sorghum bicolor (L.)], pearl millet [ Pennisetum glaucum (L.) R. Br.], and groundnut [ Arachis hypogaea (L.)] showed detectable BNI in root exudate. Among pasture grasses, Brachiaria humidicola (Rendle) Schweick, B. decumbens Stapf showed the highest BNI capacity. Several high- and low-BNI genotypes were identified within the B. humidicola species. Soil collected from field plots of 10 year-old high-BNI genotypes of B. humidicola, showed a near total suppression (>90%) of nitrification; most of the soil inorganic N remained in the NH form after 30 days of incubation. In contrast, soils collected from low-BNI genotypes did not show any inhibitory effect; most of the soil inorganic N was converted to NO after 30 days of incubation. In both the high- and low-BNI genotypes, BNI was detected in root exudate only when plants were grown with NH, but not when grown with NO as the sole source of N. BNI compounds when added to the soil inhibited nitrification and the relationship was linear ( r 2 = 0.92**; n = 12). The BNI from high- and low-BNI types when added to N. europaea in pure culture, blocked both the ammonia monooxygenase (AMO) and the hydroxylamine oxidoreductase (HAO) pathways. Our results indicated that BNI capacity varies widely among and within species; and that some degree of BNI capacity is likely a widespread phenomenon in tropical pasture grasses. We suggest that the BNI capacity could either be managed and/or introduced into pastures/crops with an expression of this phenomenon, via genetic improvement approaches that combine high productivity along with some capacity to regulate soil nitrification process. [ABSTRACT FROM AUTHOR]

The release of chemical compounds from plant roots that suppress soil nitrification is termed biological nitrification inhibition (BNI). Determining the environmental factors that control the synthesis and release of BNI-compounds from Brachiaria humidicola (Rendle) Schweick, a tropical pasture grass that thrives on acid soils, is the focus of this investigation. Because the BNI trait is related to the N status of the plant, we investigated the possibility that the expression of this trait would be related to the forms of N found in the root environment. Plants were grown with two sources of N, NH or NO for 60 days and the release of BNI-compounds monitored. Only plants grown with NH released BNI-compounds from roots. The presence of NH and possibly the secondary effect of its uptake (i.e., acidic pH) in the root environment significantly enhanced the release of BNI-compounds. Both the NH and NO grown plants responded to the stimulus from NH in the root environment. BNI-compounds found in root tissue and their release were nearly three times greater in NH grown than from NO grown plants. The BNI-compounds released from roots composed of at least three active components—Type-I (stable to pH changes from 3.0 to 10), Type-II (temporarily loses its inhibitory effect at a pH higher than a threshold pH of 4.5 and the inhibitory effect is reestablished when the root exudate pH is adjusted to <4.5) and Type-III (inhibitory effect is irreversibly lost if the pH of the root exudate reaches 10.0 or above). A major portion of BNI-compounds released in the presence of NH is of Type-I. In the absence of NH, mostly Type-II and Type-III BNI-compounds were released. The BNI-compounds inhibited the function of Nitrosomonas europaea through the blocking of both ammonia monooxygenase and hydroxylamino oxidoreductase pathways. These results indicate that the release of BNI-compounds from B. humidicola roots is a regulated function and that presence of NH in the root environment is necessary for the sustained synthesis and release of BNI. [ABSTRACT FROM AUTHOR]

A bioluminescence assay using recombinant Nitrosomonas europaea was adopted to detect and quantify natural nitrification inhibitors in plant–soil systems. The recombinant strain of N. europaea produces a distinct two-peak luminescence due to the expression of luxAB genes, introduced from Vibrio harveyi, during nitrification. The bioluminescence produced in this assay is highly correlated with NO production ( r 2 = 0.94). Using the assay, we were able to detect significant amounts of a nitrification inhibitor produced by the roots of Brachiaria humidicola (Rendle) Schweick. We propose that the inhibitory activity produced/released from plants be termed ‘biological nitrification inhibition’ (BNI) to distinguish it from industrially produced inhibitors. The amount of BNI activity produced by roots was expressed in units defined in terms of the action of a standard inhibitor allylthiourea (AT). The inhibitory effect from 0.22 μM AT in an assay containing 18.9 mM of NH is defined as one AT unit of activity. A substantial amount of BNI activity was released from the roots of B. humidicola (15–25 AT unit g−1 root dry wt day−1). The BNI activity released was a function of the growth stage and N content of the plant. Shoot N levels were positively correlated with the release of BNI activity from roots ( r 2 = 0.76). The inhibitor/s released from B. humidicola roots suppressed soil nitrification. Additions of 20 units of BNI per gram of soil completely inhibited NO formation in a 55-day study and remained functionally stable in the soil for 50 days. Both the ammonia monooxygenase and the hydroxylaminooxidoreductase enzymatic pathways in Nitrosomonas were effectively blocked by the BNI activity released from B. humidicola roots. The proposed bioluminescence assay can be used to characterize and determine the BNI activity of plant roots, thus it could become a powerful tool in genetically exploiting the BNI trait in crops and pastures. [ABSTRACT FROM AUTHOR]