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Elucidating the mechanisms and pathways involved in genotype–environment (G×E) interactions and phenotypic plasticity is critical for improving plant growth. Controlled environment agricultural systems allow growers to modulate the environment for particular genotypes. In this study, we evaluated the effects of interactions among 14 genotypes and four artificial light environments on leaf lettuce phenotypes and dissected the underlying molecular mechanism via transcriptome-based modeling. Variations in morphological traits and phytochemical contents in response to artificial light treatments revealed significant G×E interactions. The appropriate genotype and artificial light combinations for maximizing phenotypic expression were determined on the basis of a joint regression analysis and the additive main effect and multiplicative interaction model for these G×E interactions. Transcriptome-based regression modeling explained approximately 50%–90% of the G×E variations. Further analyzes indicatedRed Lettuce Leaves 4 (RLL4) regulates UV-B and blue light signaling through the effects of the HY5–MBW pathway on flavonoid biosynthesis and contributes to natural variations in the light-responsive plasticity of lettuce traits. Our study represents an important step toward elucidating the phenotypic variations due to G×E interactions in non-heading lettuce under artificial light conditions.HighlightsSeveral morphological characteristics of lettuce genotypes were altered by different light wavelengths.A defectiveRLL4allele (rll4) induces the expression of downstream genes related to UV-B and blue light signaling through activation of the HY5–MBW pathway, which enhances phytochemical accumulation in lettuce.G×E analyzes identified the ideal genotype and artificial light combinations for individual phenotypes.Transcriptome-based modeling explained approximately 50%–90% of the G×E variations.

Natural root grafting is a well-known phenomenon in perennial tree species. This study examined whether root grafting is possible between the same and different annual crop species without any surgical action by using an instrument with a narrow and tight rooting passage to evaluate the application of natural root grafting. A part of the epidermal cell layer disappeared and cortex tissues of two individual plants became fused together in most of species examined. When two different species were grafted, sequential images proved that whole cowpea tap root was inserted into the cortex layer of mung bean. These results indicated that natural root grafting of annual crop species without any surgical action is possible when the two growing roots come in contact with each other in a narrow and rigid rooting channel.

Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere in a changing climate is critical to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe and synthesize data sets and methodology to quantify the five major components of the global carbon budget and their uncertainties. Fossil CO2 emissions (EFOS) are based on energy statistics and cement production data, while emissions from land-use change (ELUC), mainly deforestation, are based on land-use and land-use change data and bookkeeping models. Atmospheric CO2 concentration is measured directly, and its growth rate (GATM) is computed from the annual changes in concentration. The ocean CO2 sink (SOCEAN) is estimated with global ocean biogeochemistry models and observation-based data-products. The terrestrial CO2 sink (SLAND) is estimated with dynamic global vegetation models. The resulting carbon budget imbalance (BIM), the difference between the estimated total emissions and the estimated changes in the atmosphere, ocean, and terrestrial biosphere, is a measure of imperfect data and understanding of the contemporary carbon cycle. All uncertainties are reported as ±1σ. For the first time, an approach is shown to reconcile the difference in our ELUC estimate with the one from national greenhouse gases inventories, supporting the assessment of collective countries’ climate progress. For the year 2020, EFOS declined by 5.4 % relative to 2019, with fossil emissions at 9.5 ± 0.5 GtC yr−1 (9.3 ± 0.5 GtC yr−1 when the cement carbonation sink is included), ELUC was 0.9 ± 0.7 GtC yr−1, for a total anthropogenic CO2 emission of 10.2 ± 0.8 GtC yr−1 (37.4 ± 2.9 GtCO2). Also, for 2020, GATM was 5.0 ± 0.2 GtC yr−1 (2.4 ± 0.1 ppm yr−1), SOCEAN was 3.0 ± 0.4 GtC yr−1 and SLAND was 2.9 ± 1 GtC yr−1, with a BIM of −0.8 GtC yr−1. The global atmospheric CO2 concentration averaged over 2020 reached 412.45 ± 0.1 ppm. Preliminary data for 2021, suggest a rebound in EFOS relative to 2020 of +4.9 % (4.1 % to 5.7 %) globally. Overall, the mean and trend in the components of the global carbon budget are consistently estimated over the period 1959–2020, but discrepancies of up to 1 GtC yr−1 persist for the representation of annual to semi-decadal variability in CO2 fluxes. Comparison of estimates from multiple approaches and observations shows: (1) a persistent large uncertainty in the estimate of land-use changes emissions, (2) a low agreement between the different methods on the magnitude of the land CO2 flux in the northern extra- tropics, and (3) a discrepancy between the different methods on the strength of the ocean sink over the last decade. This living data update documents changes in the methods and data sets used in this new global carbon budget and the progress in understanding of the global carbon cycle compared with previous publications of this data set (Friedlingstein et al., 2020; Friedlingstein et al., 2019; Le Quéré et al., 2018b, 2018a, 2016, 2015b, 2015a, 2014, 2013). The data presented in this work are available at https://doi.org/10.18160/gcp-2021 (Friedlingstein et al., 2021).

Cowpea being a dependable source of protein for human growth and development is widely cultivated in sub-Saharan Africa including Nigeria. In spite of its numerous uses, infection by viruses constitutes serious problems to its productivity and once plants are infected, there is no remedy as is with other pathogens such as bacteria, fungi and nematodes. A field trial was conducted to investigate the reactions of twenty five cowpea cultivars to single and mixed infections with two unrelated viruses: Blackeye cowpea mosaic virus (BlCMV) and Cowpea mottle virus (CPMoV) on seed germination and longevity. The trial was conducted at the Teaching and Research Farm of the Ahmadu Bello University (ABU), Zaria, Mokwa Station and set up in a randomized complete block design (RCBD) with three replicates. For the single virus infection, seedlings of the twenty five cultivars were inoculated at 10 days after sowing (DAS), while for the mixed virus infections, seedlings were inoculated at 10 and 17 DAS. Results showed that all the cultivars were susceptible to single and mixed infections but to seemingly different extents. Germination of seeds was generally high before storage but was short lived indicating that conservation of infected seeds of the cultivars was impaired. Seeds of cultivars IT04K-267-8 and IT07K-222-2 recorded germination percentages of 54.6 and 53.7% respectively, while cultivars IT96D-610 and IT04K-291-2 had germination values of 52% which did not differ from each other. Viability of seeds amongst the 25 test cowpea cultivars from single infection with CPMoV alone and BICMV alone did not differ in some instances. Percent germination in cultivars IT98K-205-M8, IT90K-277-2 and IT07K-222-2 inoculated with BICMV + CPMoV were not much affected. Test of accelerated ageing germination (AAG) percentage for four weeks showed that seed vigour was greatly impaired in cultivars IT07K-292-2-10, IT06K-124 and IT90K-277-2 infected with BICMV + CPMoV compared to the lowest AAG percentage of 31.6 recorded in seeds of cultivar IT99K-377-1. Constant monitoring of legume fields through regular field sanitation and disease surveys to identify new and emerging viruses as facts obtained from this study are good starting point for legume virus diseases diagnosis.

Soyabean is an important source of protein for millions of people in developing countries. However, infection by Cucumber mosaic virus (CMV) causes devastating losses. Cultivation of resistant varieties has been identified as the best management strategy in many crops. The present study was, therefore, conducted to identify soyabean genotypes with high stability for growth and seed weight under CMV and disease-free conditions. Thus, eight soyabean genotypes were evaluated as CMV-infected and uninfected, using completely randomised design replicated five times and set up in the screenhouse at the School of Agriculture and Agricultural Technology, Federal University of Minna, (lat.9°40֬ N;long 6°30֬ E at an altitude of 220 m.a.s.l), Nigeria in 2018. Soyabean seedlings were infected with the virus by sap transmission at 10 days after sowing (DAS). Additive Main Effects and Multiplicative (AMMI) analyses of the evaluated parameters for growth and seed weight of the test genotypes showed that environments’ effects -infected and uninfected- were significant (p

The diversification of flowering time in response to natural environments is critical for the spread of crops to diverse geographic regions. In contrast with recent advances in understanding the molecular basis of photoperiodic flowering in rice (Oryza sativa), little is known about how flowering-time diversification is structured within rice subspecies. By analyzing genome sequencing data and a set of 429 chromosome segment substitution lines (CSSLs) originating from 10 diverse rice accessions with wide distributions, we revealed diverse effects of allelic variations for common flowering-time quantitative trait loci in the recipient's background. Although functional variations associated with a few loci corresponded to standing variations among subspecies, the identified functional nucleotide polymorphisms occurred recently after rice subgroup differentiation, indicating that the functional diversity of flowering-time gene sequences was not particularly associated with phylogenetic relationship between rice subspecies. Intensive analysis of the Hd1 genomic region identified the signature of an early introgression of the Hd1 with key mutation(s) in aus and temperate japonica accessions. Our data suggested that, after such key introgressions, new mutations were selected and accelerated the flowering-time diversity within subspecies during the expansion of rice cultivation area. This finding may imply that new genome-wide changes for flowering-time adaptation are one of the critical determinants for establishing genomic architecture of local rice subgroups. In-depth analyses of various rice genomes coupling with the genetically confirmed phenotypic changes in a large set of CSSLs enabled us to demonstrate how rice genome dynamics has coordinated with the adaptation of cultivated rice during the expansion of cultivation area.

Mixed cropping is a cultivation method widely practiced in tropical regions. The newly developed close mixed planting technique mitigates the flood stress of drought-adapted upland cereal species by co-growing rice (Oryza sativa) plants under field flood conditions. We tested the hypothesis that O2 was transferred from rice to upland crops using the model system of hydroponic culture. To confirm the hypothesis, the phenomena of O2 absorption and release by plants were evaluated in a water culture condition without soil. Experiments were conducted in a climate chamber to estimate the amount of O2 released from the roots of rice and pearl millet (Pennisetum glaucum) under both O2-rich (20.0 ± .0% conc. in phase I) and O2-free dark (.8 ± .0% conc. in phase II) conditions. The total O2 change (between the two phases) in a single planting of rice and pearl millet was significantly higher than that of the mixed planting of rice and pearl millet, which indicated that O2 was transferred from rice to pearl millet under a water culture condition. The result indicated that approximately 7 μM O2 g fresh root weight−1 h−1 was transferred between the two plant species. O2 transfer was confirmed between the two plant species in a mix cultured in water, implying its contribution to the phenomenon that improved the physiological status of drought-adapted upland crops under field flood conditions.

Purpose The purpose of this paper is to examine a campus community’s knowledge and acceptance of their campus police as “real” police. Design/methodology/approach Using the liminality theoretical framework, this study surveyed students, faculty, staff, and administrators (n=1,484). Students were surveyed in-person, while staff, faculty, and administrators participated through an e-mail link to an online survey. Findings Results indicate that campus police are stuck in a liminal state. While 80 percent of the sample thought campus police should be armed, almost two-thirds (64 percent) did not know or were unsure of campus police officer tasks and three-quarters (75 percent) did not know or were unsure of campus police training requirements. Research limitations/implications The participants come from one university campus, so the generalizability of the sample is limited. Originality/value This study provides more evidence of the marginalization of campus police. Specifically, this study highlights that a majority of participants could not or were unable to identify campus police officers’ training and duties. Instead of using small qualitative samples, this study utilized over 1,400 participants on one campus, which provides more explanatory power about the perception problems of the campus police. This study also continues to advance and expand liminal theory.

We present the spatial distributions and temporal changes of the long-term variability of surface nutrient concentrations in the North Pacific by using nutrient samples collected by volunteer ships and research vessels from 1961 to 2012. Nutrient samples are optimally interpolated onto 1° × 1° monthly grid boxes. When the Pacific Decadal Oscillation is in its positive phase, nutrient concentrations in the western North Pacific are significantly higher than the climatological means, and those in the eastern North Pacific are significantly lower. When the North Pacific Gyre Oscillation is in its positive phase, nutrient concentrations in the subarctic are significantly higher than the climatological means. The trends of phosphate and silicate averaged over the North Pacific are −0.012 ± 0.005 µmol l−1 decade−1 and −0.38 ± 0.13 µmol l−1 decade−1, whereas the nitrate trend is not significant (0.01 ± 0.13 µmol l−1 decade−1).

Recently, the occurrences of extreme flooding and drought, often in the same areas, have increased due to climate change. Wetland plant species are known to oxygenate their rhizospheres by releasing oxygen (O2) from their roots. We tested the hypothesis that wetland species could help upland species under flood conditions; that is, O2 released from the wetland crop roots would ameliorate rhizosphere O2-deficient stress and hence facilitate upland crop root function. Flooding tolerance of upland-adapted staple crops—pearl millet (Pennisetum glaucum) and sorghum (Sorghum bicolor) mix-cropped with rice (Oryza spp.) was investigated in glasshouse and laboratory. We found a phenomenon that strengthens the flood tolerance of upland crops when two species—one wetland and one drought tolerant—were grown using the mixed cropping technique that results in close tangling of their root systems. This technique improved the photosynthetic and transpiration rates of upland crops subjected to flood stress (O2-deficient nutrient culture). Shoot relative growth rates during the flooding period (24 days) tended to be higher under mixed cropping compared with single cropping. Radial oxygen loss from the wetland crop roots might be contributed to the phenomenon observed. Mixed cropping of wet and dryland crops is a new concept that has the potential to overcome flood stress under variable environmental conditions.

Two sugar cane varieties were evaluated in a split plot design experiment at Badeggi (lat.9°045'N; long 607'E at an altitude of 70.57 m.a.s.l) with four whip smut (Sporisorium scitamineum) inoculum concentrations 0 x 10, 2 x 10, 4 x 10 and 6 x 10 teliospores/ml in four replicates between 1998 and 2000. The field sucrose production (% brix) was measured with a hand refractometer by using the stalks of five tagged healthy and smutted canes which were individually punched and a drop of the juice from each of them placed on the hand refractometer and covered. This was then held against the sun and viewed for the brix reading, which was recorded in percent. For the juice quality laboratory yield loss assessment, 2 healthy stalks were randomly cut from each plot and five smutted stalks were crushed using the Jeffco cutter to obtain at least 2 kg of crushed material for quality analysis. Six hundred grams of the crushed material were taken and pressed using the hydraulic hand press. The resulting juice was collected in 250 ml conical beakers. The first and last Original Research Article Wada et al.; IJPSS, 10(4): 1-11, 2016; Article no.IJPSS.24566 2 expressed brix of the juice were recorded. The temperature and hydrometer readings of the juice were also recorded. The weight of the wet bagasse was taken and again recorded after oven drying to a constant weight. These readings were used in the calculation of % reducing sugars, % Pol., Corrected brix, % Purity and % Fibre. Results showed that S. scitamineum reduced field sucrose (% Brix), % Pol., % Purity and % Fibre but increased % reducing sugars of the two test infected cane varieties.

Leifsonia xyli subsp. xyli (Lxx), the causal agent of ratoon stunting disease of sugarcane (RSD), is a major constraint to sugarcane production worldwide. In Nigeria, the presence of RSD has not been conclusively determined. This study investigated the presence or absence of RSD through surveys in 18 sugarcane growing states in Nigeria. Sugarcane plants or ratoon crops of 7–12 months of age were randomly sampled, and a total of 1190 samples of sugarcane stem cuttings from 76 cultivars were collected. The lowest four internodes were cut longitudinally into nodes, and examined internally for reddish comma-like discoloration. PCR was conducted on DNA extracted from sugarcane sap using Lxx-specific primers. Reddish comma-like internal symptoms of RSD were observed only in samples of cultivar Co510. None of the sugarcane samples, including those from Co510, yielded the 438 bp band expected for PCR detection of Lxx. Immunofluorescence microscopy analyses performed at SASRI, South Africa, using sap from the collected sugarcane samples, also did not detect the bacterium. Thus, the presence of RSD of sugarcane in Nigeria was not confirmed, contrary to its reported presence in 1956. Strict quarantine procedures should be followed to prevent introduction of the pathogen into Nigeria.

The involvement of salicylic acid (SA) in the regulation of stress-induced flowering in the short-day plant pharbitis (also called Japanese morning glory) Ipomoea nil (formerly Pharbitis nil) was studied. Pharbitis cv. Violet was induced to flower when grown in 1/100-strength mineral nutrient solution under non-inductive long-day conditions. All fully expanded true leaves were removed from seedlings, leaving only the cotyledons, and flowering was induced under poor-nutrition stress conditions. This indicates that cotyledons can play a role in the regulation of poor-nutrition stress-induced flowering. The expression of the pharbitis homolog of PHENYLALANINE AMMONIA-LYASE, the enzyme activity of phenylalanine ammonia-lyase (PAL; E.C. 4.3.1.5) and the content of SA in the cotyledons were all up-regulated by the stress treatment. The Violet was also induced to flower by low-temperature stress, DNA demethylation and short-day treatment. Low-temperature stress enhanced PAL activity, whereas non-stress factors such as DNA demethylation and short-day treatment decreased the activity. The PAL enzyme activity was also examined in another cultivar, Tendan, obtaining similar results to Violet. The exogenously applied SA did not induce flowering under non-stress conditions but did promote flowering under weak stress conditions in both cultivars. These results suggest that stress-induced flowering in pharbitis is induced, at least partly, by SA, and the synthesis of SA is promoted by PAL.

Many plant species are induced to flower by stress. Stress-induced flowering has been studied mostly in the short-day plant pharbitis (also called Japanese morning glory; Ipomoea nil, formerly Pharbitis nil). In this article, physiological characteristics, the regulation by salicylic acid (SA) and the expression of flowering-related genes in stress-induced flowering in pharbitis are reviewed. Pharbitis flowered under long-days in response to poor nutrition or low temperature. The pharbitis plants induced to flower by stress reached anthesis, fruited and produced fertile seeds. The progeny of the stressed plants developed normally. Grafting experiments indicated that a transmissible flowering stimulus is involved in poor nutrition stress-induced flowering. Aminooxyacetic acid (AOA), a phenylalanine ammonia-lyase (PAL) inhibitor, inhibited the stress-induced flowering, and this inhibition was overcome by SA. Stress induced PAL activity and SA biosynthesis. PnFT2, a pharbitis ortholog of the flowering gene FLOWERING LOCUS T of Arabidopsis thaliana, was expressed when the plants were induced to flower by stress. The overexpression of PnFT2 induced flowering, and PnFT2RNAi inhibited it. AOA inhibited PnFT2 expression induced by stress, and SA eliminated this inhibitory effect. SA enhanced PnFT2 expression under poor nutrition but not under non-stressful conditions. Therefore, stress may induce the production of SA and other unknown factor(s) that may work in combination to induce PnFT2 expression and flowering.

Gun violence at American colleges and universities has rekindled the debate surrounding concealed weapons on campus. This study examined college student and faculty opinions on two college campuses, focusing on their attitudes towards private citizens carrying concealed guns on campus. Data were collected during the fall 2008 and spring 2009, and over 2,100 students, staff, faculty, and administrators on the two campuses participated in the research. The results indicate over 70 % of respondents oppose the option of carrying concealed guns on campus. In addition, the idea of more guns on campus makes the majority of students and faculty feel less safe, and allowing concealed weapons serves to decrease the sense of campus safety. This study continues to empirically advance the argument that those who live, work, and study do not want more guns on campus. Further research in this area, including an expanded range of the nation’s college campuses, should be explored.

The short-day plant, Lemna paucicostata (synonym Lemna aequinoctialis), was induced to flower when cultured in tap water without any additional nutrition under non-inductive long-day conditions. Flowering occurred in all three of the tested strains, and strain 6746 was the most sensitive to the starvation stress conditions. For each strain, the stress-induced flowering response was weaker than that induced by short-day treatment, and the stress-induced flowering of strain 6746 was completely inhibited by aminooxyacetic acid and l-2-aminooxy-3-phenylpropionic acid, which are inhibitors of phenylalanine ammonia-lyase. Significantly higher amounts of endogenous salicylic acid (SA) were detected in the fronds that flowered under the poor-nutrition conditions than in the vegetative fronds cultured under nutrition conditions, and exogenously applied SA promoted the flowering response. The results indicate that endogenous SA plays a role in the regulation of stress-induced flowering.

PurposeThe literature on campus police (CP) is not as developed as mainstream or municipal police (MP). While there are several studies discussing the perception of CP, there are, however, no empirical studies investigating the perception of CP based on their legitimacy. Through the theoretical framework of liminality, this paper aims to address the literature gap by examining the perceived legitimacy of CP compared to MP.Design/methodology/approachData were collected through the use of survey instruments distributed among 593 college undergraduates at a doctoral extensive land grant institution in the Pacific Northwest. Since the purpose of the study was to determine student perceptions of legitimacy between MP and CP, two surveys were utilized to capture those perceptions, one for each police group respectively. The two sets of surveys were equally administered in each selected class.FindingsThrough the framework of liminality, this research demonstrates the marginalization of CP as sworn law enforcement officers, especially when compared to their MP counterparts.Research limitations/implicationsAs this is the first study addressing the perceived legitimacy of the CP there needs to be further research in this area before substantial conclusions can be reached. Future research in this area should address the opinions of minority students, faculty and staff. Additionally, CP and MP officers themselves should be assessed to determine any potential legitimacy concerns based on perception.Originality/valueThe theoretical framework reveals that the CP are trapped in a liminal state and are unable to transition into perceived legitimate police officers.

The cytidine analogue 5-azacytidine (azaC), which causes DNA demethylation, induced flowering in the long-day plant Silene armeria and the short-day plant Perilla frutescens var. crispa under non-inductive photoperiodic conditions, suggesting that the expression of photoperiodic flowering-related genes is regulated by DNA methylation. The progeny of plants induced to flower by azaC did not flower under non-inductive photoperiodic conditions. The DNA gel blot hybridization analysis revealed no differences in the methylation states of genomic DNA from the azaC and control progeny in P. frutescens. These results suggest that the flowering-related genes activated by DNA demethylation were remethylated in the progeny. This remethylation system may allow the genes to be demethylated in response to inductive photoperiodic conditions in each generation. The azaC treatment also induced dwarfism in P. frutescens, and this characteristic was inherited by the progeny. Similar relationships between the azaC-induced dwarfism and the demethylation/remethylation system could not be established. Genome-wide methylation changes were examined by methylation-sensitive amplified fragment length polymorphism (MS-AFLP) analysis in P. frutescens, and the results showed that the DNA methylation state was altered by photoperiodic conditions.

The farming systems of Zone II of the Niger State Agricultural Development Project (NSADP) were surveyed in September 2000. All the nine Local Government Areas (LGAs) covering three ecological zones of the zone were covered in the selection of villages for the group and individual interviews with farmers in the administration of questionnaires. Farms were visited and assessed for extent of damage caused by insect, weeds, vertebrate and avian pests as well as diseases. Weeds of economic importance in the zone were Striga hermonthica (Del) Benth; Rottboellia cochinchinensis (Lour) Clayton; Ageratum conyzoides L.; Cyprus rotundus, C. distans and Commelina benghalensis L. Maize streak virus, rice blast and groundout rosette were the damaging diseases of maize, rice and groundnut, respectively. Bush fowl, Quelea sp. and monkeys were the most serious avian and vertebrate pests, respectively. Farmers' management practices for these pests were documented. Short- and long-term solutions to these problems are to be...

The flower-inducing effect of 5-azacytidine, a DNA demethylating reagent, was examined in several plant species with a stable or unstable photoperiodically induced flowering state under non-inductive photoperiodic conditions. The long day plant Silene armeria, whose flowering state is stable and the short day plant Pharbitis nil, whose flowering state is unstable were induced to flower by 5-azacytidine under a non-inductive condition. Thus, the replacement of photoinduction by 5-azacytidine treatment is not specific to Perilla frutescens. On the other hand, 5-azacytidine did not induce flowering in Xanthium strumarium whose flowering state is stable and Lemna paucicostata whose flowering state is unstable. Thus, epigenetics caused by DNA demethylation may be involved in the regulation of photoperiodic flowering irrespective of the stability of the photoperiodically induced flowering state.

Field experiments were conducted at Numan (Lat. 9° 32’- 9° 40’ N and Long. 11° 49’- 12° E) on three crop cycles, Plant (P), first ratoon (1R) and second ratoon (2R), from 1997 to 2000. This was to asses the performance of seven commercial and pre-commercial varieties of sugarcane on the two major soil types. The experimental design used was Randomized Complete Block Design (RCBD), laid out in four replicates. The results showed that varieties Co 957, IB84-83, and IB85-85 gave significantly higher values for the tillering trait on the two soil types for the three year cropping. Cultivar B61208 recorded the tallest cane plants among the test varieties on the two soil types for the three years. The best variety for cane and sugar yields for both soils was Co 957, which was followed by IB84-83 and IB85-85 for the vertisols and alluvial soils respectively. The prospects for utilizing the IB varieties in commercial cultivation in the two soil types at Numan is discussed.

The effort to develop brown sugar processing technology in Nigeria was initiated by the Federal Government in 1986 through the Federal Ministry of Industries. The first prototype plant of 2 tons per day cane - crushing capacity was designed, fabricated and tested by the National Cereals Research Institute, Badeggi in 1988. Since then several research activities have been carried out in order to improve the efficiency of the plant and also up-grade its capacity. The basic unit processes are : weighing, crushing, clarification (liming, heating and settling), evaporation, crystallization, centrifugation and drying. Designs of equipment for each of the unit processes were provided by the Institutes engineers. Fabrication materials were procured locally and all the equipment were fabricated through indigenous effort. Test results of the prototype plant using three varieties of Sugarcane BD96-001, BD96-003 and BD96-009 indicated average sugar recovery rate of 6.3–6.5%. The quality of the sugar, compared with existing one at the Nigeria Sugar Company Limited (Nisuco), Bacita was also acceptable.

Polyglutamine (polyQ) aggregate bodies are a hallmark of dentatorubral-pallidoluysian atrophy and related neurodegenerative disorders, although the relationship between aggregate body formation and cell death is not clear. We analyzed the kinetics of polyQ aggregate formation and the time intervals for cell death, tracking individual cells using fluorescence video microscopy, for the first time. Expanded polyQ tracts of atrophin-1 with or without nuclear localization signal (NLS) labeled with green fluorescent protein (GFP) were constructed, Q57NLS/GFP and Q56/GFP, respectively. All of the Q57NLS/GFP aggregate bodies were in nuclei, and all of the Q56/GFP aggregate bodies were in cytoplasm. Aggregates of Q56/GFP were larger than those of Q57NLS/GFP. Surprisingly, a kinetic analysis showed that the latter grew 5.37 times faster than the former. The time interval between transfection and cell death was shorter in Q57NLS/GFP, but the time between the end of the rapid growing phase of aggregation and the start of the cell death process did not show a significant difference. Aggregate growth was confirmed to correspond to the accumulated free polyQ by the time of starting aggregation. These findings suggest that aggregate body formation induced by expanded polyQ stretches is a self-limiting process and is enhanced by factor(s) in nuclei, whereas it is not tightly bound to the cell death process. © 2002 Wiley-Liss, Inc.

The red-leaved form of Perilla frutescens var. crispa was induced to flower by low-intensity light stress. The leaves of this form are normally red, but turned green under low-intensity light due to anthocyanin depletion in the epidermis. Flowering did not occur when plants were grown under light passed through a red-colored cellophane paper, which has an absorption spectrum similar to that of anthocyanins. High-concentration anthocyanins may play the role of a red-colored optical filter under normal light conditions, and this filter effect may be lost under low-intensity light, causing a change in the wavelength characteristics of the light with which the mesophyll cells are irradiated. This change may induce a photobiological effect leading to flowering. The gene expression and enzyme activity of phenylalanine ammonia-lyase (PAL), the key enzyme for anthocyanin biosynthesis, decreased under low-intensity light. L-2-aminooxy-3-phenylpropionic acid (AOPP), which is widely used as a PAL inhibitor, inhibited low-intensity light stress-induced flowering and increased PAL activity and anthocyanin content. The inhibition of flowering by AOPP in P. frutescens may be through different mechanisms than PAL inhibition.

Background During the transition from the logarithmic to the stationary phase, 70S ribosomes are dimerized into the 100S form, which has no translational activity. Ribosome Modulation Factor (RMF) is induced during the stationary phase and binds to the 50S ribosomal subunit, which directs the dimerization of 70S ribosomes. Unlike many other genes induced in the stationary phase, rmf transcription is independent of the sigma S. To identify the factors that regulate the growth phase-dependent induction of rmf, mutant strains deficient in global regulators were examined for lacZ expression directed by the rmf promoter. Results Among mutants of defective global regulators, only ppGpp deficiency (relA-spoT double mutant) drastically reduced the level of rmf transcription to less than 10% of that seen in the wild-type. Neither RMF nor 100S ribosomes were detected in this mutant in the stationary phase. rmf transcription correlated well with cellular ppGpp levels during amino acid starvation, IPTG induction of Ptrc-relA455 and in other mutants with artificially increased ppGpp levels. Although the growth rate also correlated inversely with both ppGpp levels and rmf transcription, the observation that the growth rates of the ppGpp-deficient and wild-type strains varied equivalently when grown on different media indicates that the link between rmf transcription and ppGpp levels is not a function of the growth rate. Conclusions ppGpp appears to positively regulate rmf transcription, at least in vivo. Thus, RMF provides a novel negative translational control by facilitating the formation of inactive ribosome dimers (100S) under the stringent circumstances of the stationary phase.

In the development of the sugar industry in Nigeria, Sugarcane Research and Development (R & D) are very important. The National Cereals Research Institute, Badeggi is currently progressing with some significant success. However, the sugar estates, the government and the private sector needed to help to adequately fund R & D on sugarcane and sugar for their effective contribution to the national economy. A free flowing brown sugar technology has been developed from indigenous research and engineering efforts at National Cereals Research Institute to promote increased sugar production in the country. This is a cost saving measure on continued sugar imports. This paper briefly reviews the current R&D efforts on sugarcane and sugar production in Nigeria against the backdrop of the National Agricultural Policy. It highlights the reasons for the lack lustre performance of the domestic sugar sector and demonstrates the potential impact of a locally developed sugarcane processing technology in the national economy. Suggestions are also made to policy makers and other stakeholders in the sugar industry to encourage local sugar production and R & D on sugarcane and sugar for its contribution to the nation’s economy.