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Corn production for concentrated feed is increasing in Japan, and cultivation techniques are necessary to obtain higher yields. To expand the corn production for concentrated feed in the Kanto region of Japan, corn varieties based on their earliness was evaluated. Changes in ear yield and moisture content were compared among 12 commercial varieties, which were divided into three groups based on their relative maturity (RM): extremely early (RM 95–100), early (RM 113–115) and medium (RM 125). The varieties were sown at three different times (late April, middle May and late May) for three cultivation years. Our experiment found that the ear dry weights of both early and medium groups were higher than that of the extremely early group. Ear moisture of the extremely early group decreased rapidly and reached 35% as a standard for harvesting time we defined, at 60 days after silking, while that of the early group reached 35% at 70 days after silking, and that of the medium group did not reach 35% during the experimental period. Late sowing decreased ear dry weight and delayed ear moisture decreasing. The extremely early group had the advantage of early harvesting at 60 days after silking, and the early group obtained a higher yield than the extremely early group at the harvesting at 70 days after silking. These results suggest that extremely early and early groups are suitable for corn production for concentrated feed in the Kanto region. [ABSTRACT FROM AUTHOR]

Despite the existing contributions on the economic and social relevance of industrial clusters in the firms' internationalization, research on these topics is still scarce and, particularly, controversial at an empirical level. This study contributes to the extant literature on international development, proposing to explore the impact that industrial clusters and innovation activities exert in the most relevant temporal dimension of the firm's foreign expansion—internationalization speed (earliness and postentry speed). Further, this research seeks to ascertain whether the relationship between industrial clusters and internationalization speed is significantly different for low and high‐technology businesses. Based on a sample of 3,537 Portuguese firms, collected in the SABI database, the results suggest that firms belonging to industrial clusters and developing innovation activities tend to exhibit a higher postentry speed, not observing the same impact in terms of early internationalization. The findings also reveal that low‐technology firms have an additional incentive to become involved in industrial clusters, since these actions will be reflected to a greater extent in their postentry speed than those of high‐technology firms. [ABSTRACT FROM AUTHOR]

Potato is very susceptible to weed interference during the early growth stages due to slow emergence, and again at the end of the growing cycle when branches collapse and the canopy opens. Weed control usually is performed through a combination of physical and chemical methods. A growing concern for the environment and human health has encouraged the development of non-chemical weed control. We evaluated the effects of an integrated weed management strategy consisting of physical and cultural methods on naturally emerging weeds over two field seasons in central Italy. One harrowing plus one hilling operation were conducted during the early crop stages, and the competitive abilities against late emerging weeds of six different cultivars of potato, characterised by differences in developmental timing and growth habit, were evaluated. Two measures of competition were evaluated, the competitive balance index (Cb) and the relative total biomass of crop and weed. Higher competitive ability (Cb) was associated with traits such as fast early above-ground biomass production, height and final above-ground biomass. Medium late maturity cultivars showed higher Cb than earlier ones, but this was associated with lower yield, providing evidence for a trade-off between competitive ability and yield. The trade-off was in part biased by the lack of adaptation of the medium late cultivars to hot weather conditions, so we concluded that cultivars characterised by different developmental time need to be screened and tested for local systems. [ABSTRACT FROM AUTHOR]

Predicting and understanding the progress towards flowering in faba bean are important to achieve the adaptation and high productivity of the crop under varying environmental conditions. Traditional controlled-environment experiments showed that the rate of progress towards flowering was dependent mainly on photoperiod and temperature. Here, we highlight the need to include measures of solar radiation and water deficit in order to achieve an adequate model for field conditions. The improved model was assessed in two steps: first with a 'basic' model across all 20 cultivars and then with an 'extended' model that included terms to fit exceptional cultivars. The two new parameters were necessary to achieve an acceptable fit of progress towards flowering and clearly separated two cultivars, 'Kontu' and 'Witkiem Manita,' that were significantly quicker to flower than the other 18, which fit a single line. As the regression coefficients of the two exceptional cultivars differed only in intercept, not slope, we conclude that flowering responses to day length, temperature, solar radiation and drought stresses were consistent in this set of germplasm and that the two cultivars differed in earliness ' per se.' Growth-chamber experiments added information about differing ceiling temperatures for progress to flowering in four cultivars and different sensitivities to supraoptimal temperatures. [ABSTRACT FROM AUTHOR]

Improved adaptation of winter wheat ( Triticum aestivum L.) to drought and heat may be influenced by days to heading, plant height, biomass, canopy temperature (CT) at grain filling, and rate of senescence. This study shows that, under supplemental irrigation or rainfed conditions, days to heading and plant height together explain up to 68% of grain yield (GY) variation, and these associations were further confirmed in several locations across West and Central Asia. Days to heading can be slightly reduced below that of check line Karahan to further improve GY while avoiding the effect of late frosts. Plant height has been decreased in recent germplasm, but further reductions below that of check line Karahan could still improve GY in a wide range of environments. However, in Iranian sites, taller genotypes showed better adaptation with higher biomass and increased reserves for grain filling. Canopy temperature and rate senescence were not associated with GY. A normalized difference vegetation index, used to estimate biomass (Feekes stages 4-5), had intermediate heritability across environments and correlated positively with GY under low plant density and should be explored further as a tool for early selection. [ABSTRACT FROM AUTHOR]

The leafy heads of cabbage ( Brassica oleracea), Chinese cabbage ( Brassica rapa ssp. pekinensis), Brussels sprouts ( B. oleracea ssp. gemmifera) and lettuce ( Lactuca sativa) comprise extremely incurved leaves that are edible vegetable products. The heading time is important for high quality and yield of these crops. Here, we report that BrpSPL9-2 ( B. rapa ssp. pekinensis SQUAMOSA PROMOTER BINDING-LIKE 9-2), a target gene of micro RNA brp-miR156, controls the heading time of Chinese cabbage. Quantitative measurements of leaf shapes, sizes, colour and curvature indicated that heading is a late adult phase of vegetative growth. During the vegetative period, miR156 levels gradually decreased from the seedling stage to the heading one, whereas BrpSPL9-2 and BrpSPL15-1 m RNAs increased progressively and reached the highest levels at the heading stage. Overexpression of a mutated miR156-resistant form of BrpSPL9-2 caused the significant earliness of heading, concurrent with shortening of the seedling and rosette stages. By contrast, overexpression of miR156 delayed the folding time, concomitant with prolongation of the seedling and rosette stages. Morphological analysis reveals that the significant earliness of heading in the transgenic plants overexpressing BrpSPL9-2 gene was produced because the juvenile phase was absent and the early adult phase shortened, whereas the significant delay of folding in the transgenic plants overexpressing Brp-MIR156a was due to prolongation of the juvenile and early adult phases. Thus, miR156 and BrpSPL9 genes are potentially important for genetic improvement of earliness of Chinese cabbage and other crops. [ABSTRACT FROM AUTHOR]

The article presents a study on a new, efficient and nontrivial Mixed Integer Program (MIP) formulation that can be used on variety of single machine scheduling problem. It notes that the introduced MIP is closely related to the well-known time-indexed MIP formulation but utilizes less variables and constraints. Based on the experiments on academic benchmarks and real-life industrial problems, it is concluded that the generic MIP formulation is efficient.

Drought is an important yield-reducing factor for corn and soya bean which are the two major crops in the Delaware, Maryland and Virginia (Delmarva) region of the United States. Cowpea (Vigna unguiculataL. Walp.) is primarily grown in drier regions of the world where it is one of the most drought-resistant food legumes. Field experiments were conducted in which 10 genetically diverse cowpea genotypes were evaluated for adaptability to the Delmarva area. The cowpea genotypes were grown in rain-out shelters under non-water-stressed and water-stressed conditions. The results showed that under non-water-stressed conditions cowpea genotypes California Blackeye 5, Champion and Mississippi Silver gave higher seed yields, while genotypes White Acre, Six Week Browneye and Texas Cream 8 provided lower seed yields. Genotypes California Blackeye 5 and Champion gave comparatively better seed yields under water-stressed conditions. California Blackeye 5 was the highest seed-yielding genotype under both water-stressed and non-water-stressed conditions. The highest biological yield under non-water-stressed conditions was given by genotypes Two Crop Brown, White Acre and Elite, whereas under the water-stressed condition genotypes Texas Cream 8, California Blackeye 5, and Mississippi Silver gave higher biological yield. Genotypes Quickpick Pinkeye and Elite were identified as early maturing genotypes. The harvest index (HI) varied significantly among genotypes, with Texas Cream 8 having the lowest HI. Cowpea genotypes which gave higher seed yield under water-stressed conditions could play an important role in sustaining crop production in the Delmarva region. [ABSTRACT FROM AUTHOR]

Thirty-nine barley varieties of different origin, representing different growth types, were included in a series of experiments aimed at analysing the variability in vernalization response, photoperiod sensitivity and earliness per se and establishing the types of ecoclimatic adaptability using multivariate analysis. In the case of spring barley varieties there was no correlation between any of the three traits. For winter barleys, a negative correlation was found between photoperiod sensitivity and vernalization response and between photoperiod sensitivity and earliness per se. Vernalization response and earliness per se showed a positive correlation. Among the winter barley varieties large variations were apparent in photoperiod sensitivity, vernalization response and earliness per se, which resulted in a tremendous variation in flowering patterns and frost tolerance. Between the spring barley varieties only wider variations in photoperiod sensitivity were detected. Based on the cluster analysis, the 39 varieties could be separated into seven groups. The spring barley varieties were placed in two groups, and the winter barleys in five groups representing different adaptational types. Among these five groups two represented the two opposing extreme combinations of photoperiod sensitivity and vernalization response. The combination of large photoperiod sensitivity and no vernalization response resulted in better frost tolerance than did the combination of photoperiod insensitivity and large vernalization response. [ABSTRACT FROM AUTHOR]

The inheritance of heading time of spring barley was studied in three extremely early genotypes IB, RL and ‘Mona’ (M), which is homozygous recessive for the early maturity ea8 (= eak) gene conferring extreme earliness under short daylengths and is relatively photoperiod insensitive, and five (GP, MA, PS, NU and BA) spring genotypes that are early to intermediate for heading time. Frequency distributions of F2 generations grown at Ouled Gnaou, Morocco (32°15′ N), an environment which maximizes differences between photoperiod-insensitive and photoperiod-sensitive genotypes, indicated that across populations many loci were segregating in a complex Mendelian manner. IB and RL were both homozygous recessive for the ea8 gene, which conferred an early heading time. RL had partially dominant alleles at second locus (Enea8), which enhanced its earliness. Recovery of only progeny within the parental range of genotypes for heading time from the crosses of RL/M and IB/M suggests that numerous loci remained suppressed, perhaps latent, given their diverse parentage. The ea8 recessive homozygote in RL suppressed another unidentified locus which, when homozygous recessive in the absence of the ea8 recessive homozygote, conferred extreme earliness in one short daylength environment (Ouled Gnaou, Morocco) but was undetected in another environment (Davis, CA, USA). Epistatic gene action and genotype × environment effects strongly influenced heading time. In addition to a genetic system consisting of single-locus recessive homozygotes conferring photoperiod insensitivity, a second genetic system, based on dominant alleles at one or a few loci, derived from the early heading Finnish landrace ‘Olli’, also confers extremely early heading time under short daylengths and relative photoperiod insensitivity in the genotype GP. [ABSTRACT FROM AUTHOR]

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Data are presented on the accumulation of nitrogen and total biomass into wheat plants at different stages in their ontogeny. Five genotypes of highly diverging; origin and with widely deviating grain protein contents were cultivated at different nitrogen regimes (ranging between 0 and 150 kg N ha-1). Growth curves as polynomials were calculated from representative subsamples of plant material collected from each plot at weekly intervals, commencing early in the vegetative stage and ending at complete maturity. Dry weights and nitrogen contents were determined for above-ground plant parts and for grains, when present, and were expressed per m² ground area. During the first 2 years total green areas were estimated as well and leaf area indices (LAIs) calculated and fitted to polynomials. The results from these trials revealed that the two American high-protein genotypes Goertzen 5559 and Frontiersman produced distinctly less biomass (mainly carbohydrates) than the Swedish genotypes Folke, Solid, and Lantvete during the later phases of growth. The lower biomass production of the American types after anthesis appeared to be more due to a decreased photosynthetic activity and less to a decrease in green area. It was also found that the American genotypes had a higher efficiency in remobilizing previously produced and stored assimilates than the modern Swedish cultivars Folke and Solid, which were more dependent on current photosynthesis. With respect to uptake of nitrogen into biomass there was very little variation between the genotypes at the early stages of plant life, but later on clear differences developed between the American and Swedish genotypes. Thus the former accumulated considerably less nitrogen than the latter, but since the differences between the two groups were still more pronounced regarding accumulation of biomass the American types exhibited higher concentrations of nitrogen in total biomass towards the end of the growing season. This higher concentration of N seems to indicate an increased relative ability for the American types to take up nitrogen from the soil during the grain filling phase but it is uncertain whether a causal relationship actually exists with the ability to accumulate protein in the grains. Estimates of the efficiency to redistribute nitrogen to the grain did not show any significant differences between the five genotypes and the most probable explanation for the high grain protein values of the American genotypes therefore seems to be their relatively low production of carbohydrates (and biomass). In a subsequent paper results from a comprehensive field trial concerning grain and straw yields, structural yield components, soil analyses, etc. will be presented which further corroborate these conclusions. [ABSTRACT FROM AUTHOR]

The aim of this article is to point out some flaws in the mathematical programming model proposed by Tamer Eren [Human and Machine Effects in a Just-In-Time Scheduling Problem, Human Factors and Ergonomics in Manufacturing, 19(4), 294-299 (2009)]. Ignoring these flaws may cause unexpected computational results. © 2010 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]