The objective of this study was to evaluate and quantify the genetic divergence between accessions of cowpea, aiming to identify the characters that most contribute to diversity and select superior parents. Seventy-six cowpea accessions were evaluated using 19 descriptors that were also utilized to estimate genetic diversity using the Shannon-Weaver index. Phenology and production data were analyzed using descriptive statistics and were subjected to Pearson's correlation test. The descriptors flower color, pod color, and seed brightness showed greater variability in the quantification of genetic diversity. The genotypes Das Almas, Galanjão, selected from CE-13, 7907-Purple Hull and Caupi Branco should be incorporated into cowpea breeding programs as they exhibit desirable agronomic characters. Crossings involving the genotype 7907-Purple Hull with Das Almas and Galanjão are indicated, which could result in obtaining superior genotypes in terms of precocity and grain yield.
19 Digit Product Key For Minitab 16
The cowpea [Vigna unguiculata (L.) Walp.] represents one of the most relevant and strategic food sources for the tropical and subtropical regions of the planet. In Brazil, the cultivation of cowpea has traditionally been concentrated in the Northern and Northeastern regions. However, it has been expanding to other regions, mainly to the Midwest, due to its wide adaptability to tropical conditions, low production costs, and intense breeding approaches applied to the cultivation (Freire Filho et al., 2011).
The cowpea breeding programs are usually based on the selection of parents followed by hybridization to form a base population and an advanced generation. This occurs with simultaneous selection of more than one characteristic, such as productivity, size, resistance to pests and diseases, and grain quality (Bertini et al., 2009). Therefore, the previous characterization of the available germplasm becomes indispensable since it allows the breeder to explore the existing genetic diversity and evaluate its potential for use in the breeding program (Oliveira et al., 2017).
In recent years, several authors have evaluated genetic divergence in cowpea (Santos et al., 2014; Sousa et al., 2017; Santana et al., 2019). For example, Santana et al. (2019) evaluated the genetic divergence between cowpea genotypes by morpho-agronomic traits in the state of Pernambuco, and they found that the combinations Pitiúba x Cabeçudo and Pitiúba x Manteiga could result in hybrids with greater heterotic effect. Santos et al. (2014) evaluated the agronomic performance and genetic divergence between cowpea genotypes grown in the Cerrado/Pantanal ecotone region. They found that the crossings of MNC03 737F 5 4 with MNC03 725F 3 and MNC03737F 5 11 obtained promising populations in terms of grain productivity.
The following variables were also collected: average number of days from emergence to full flowering (NDEFF), average number of days from emergence to pod formation (NDEPF), average number of days from emergence to physiological maturation (NDEPM), average number of days from emergence to harvest point (NDEHP), number of pods per plant (NPP), and production per plant (P/Pl).
The data obtained from the phenological and production characters were analyzed using descriptive statistics and subjected to Pearson's correlation test, with all statistical analyses performed using the Minitab software version 18.1.
According to Barros et al. (2011), compound inflorescence has a direct influence on production by morphologically altering the reproductive part of the plant, which causes bifurcations at a certain height of the peduncle and new segments that will produce flowers and fruits. Group V consisted of two components (23 and 75), the only ones that had anthocyanin pigmentation in the seedling phase.
Table 3 shows the descriptive statistics of the phenological and production variables used in the characterization of the 76 cowpea genotypes. The amplitude of the coefficient of variation (CV) varied from 9.19 to 59.44% for NDEHP and P/Pl, respectively. Santana et al. (2019), in a study of genetic divergence between cowpea accessions, found a smaller amplitude for CV values, which varied from 4.39 to 23.65% for the characters grain index and grain yield, respectively. In studies with cowpea, it is common to find high CV values for grain production (Bertini et al., 2009; Públio Júnior et al., 2017; Camara et al., 2018; Souza et al., 2019).
NDEFF - average number of days from emergence to full flowering; NDEPF - average number of days from emergence to pod formation; NDEPM - average number of days from emergence to physiological maturation; NDEHP - average number of days from emergence to harvest point; NPP - number of pods per plant; P/Pl - production per plant; CV - coefficient of variation.
According to Freire Filho et al. (2005), precocity is a relevant character as it represents the possibility of up to three crops per year, including rainfed and irrigated crops. As a result, it should be possible to increase and/or stabilize cowpea production in regions with long periods of drought. Thus, the mentioned descriptors were relevant and should be considered when selecting parents since they are directly related to the cultivation cycle.
FIGURE 3 Frequency distribution of the 76 cowpea genotypes evaluated for six characters. A) NDEFF - average number of days from emergence to full flowering; B) NDEPF - number of days from emergence to pod formation; C) NDEPM - number of days from emergence to physiological maturation; D) NDEHP - number of days from emergence to harvest point; E) NPP - number of pods per plant, and F) P/Pl - production per plant.
A more uniform distribution was observed for P/Pl, with about 93% of accessions producing less than 100 g and only five accessions with higher production, with emphasis on genotypes 1 (Das Almas) and 5 (Galanjão), which produced more than 130 g/plant (Fig. 3F). The low production values recorded for most genotypes are due to the low weight of 100 grains and the low number of grains per pod.
Regarding the estimated linear correlation between quantitative characters, an amplitude from -0.016 to 0.933 was found (Tab. 4). Pearson's correlation coefficient (r) measures the strength of the relationship between the characters studied, assuming values between -1 and 1, which are interpreted as perfect negative and positive correlations, respectively. According to the values shown in Table 4, the variables NPP and P/Pl were highly correlated (r = 0.886; P = 0.000). These results corroborate the findings of Santos et al. (2012) and show that the accessions that expressed the highest number of pods also showed higher production.
NDEFF - average number of days from emergence to full flowering; NDEPF - average number of days from emergence to pod formation; NDEPM - average number of days from emergence to physiological maturation; NDEHP - average number of days from emergence to harvest point; NPP - number of pods per plant; P/Pl - production per plant; upper cells show the correlation coefficient and lower cells show the P-value.
Of the 76 accessions evaluated in this study, five deserve to be mentioned and should be incorporated into cowpea breeding programs. They are: 1 (Das Almas), 5 (Galanjão), 13 (Selected from CE-13), 23 (7907-Purple Hull), and 46 (Caupi Branco). Accession 23 was considered the most precocious of all. However, it showed a low NPP and, therefore, low grain production. The other five genotypes combined medium cycle, NVP above average, and production above 100 g per plant.
The February 3 issue of Tor.com, which I have added, has a review of the first three episodes of the Serial Box serial The Witch Who Came In from the Cold (not yet in the DB). Now I am not sure how to add that serial; but their previous production Bookburners provides a model. Would anyone like to enter The Witch... into the DB and link the review to it? (Currently I have the Tor.com article as ESSAY not REVIEW). --Vasha 02:44, 16 January 2017 (UTC)
I believe there has been some discussion on what constitutes a publisher in the past and I thought I would bring it up in light of self-publishing becoming more common due to the proliferation of on-demand printers, ebook distributors, etc. (e.g., CreateSpace, Kindle Direct Publishing Smashwords/Smashwords, etc.) Many of these seem to masquerader as publishers but what really is a publisher? In my mind, a publisher is just a literary publicist which happens to have a somewhat special place in that they are historically listed on the copyright page and thus can be used to identify publications. Part of this process is the definition of a literary product or edition and allocation of an ISBN (a standardized literary product/edition identifier).
I am currently working on adding support for "third party identifiers" like ASINs and LCCNs. It would appear that different Amazon stores (UK, FR, JP, etc) can use different ASINs for most of their products. However, e-books appear to be an exception: the same ASINs are apparently used by all of their stores. If true, it means that we probably won't need separate country-specific ASIN IDs (or Notes templates) once we add support for third party identifiers. The display will look something like:
Calf behaviour was continuously filmed using closed circuit television (CCTV) cameras (Sony CCD, Vari-focal, 700 TV L, Sony, Minato, Japan) as described previously [55], and the video footage was stored on digital video recorders (DVR) (Guardian II+DVR 8 Channel, Digital Direct Security, Huntingdon, UK) on the farm. The required footage was regularly backed up onto an external hard drive (Seagate 1TB portable external hard drive, Seagate Technology LLC, Cupertino, CA, USA) for long-term storage and to facilitate analysis.
For the purposes of identification on the video footage, the calves were marked using agricultural marker spray, and each calf was photographed to further aid and confirm identification; for the purposes of analysis, the calves were identified by the last four digits of their official UK identification number. The date and time of birth and the animal identification number were recorded by the farm staff. The calf birthweight, the number of the pen the calf was moved to and the time at which each calf was moved into the pen were all recorded by the researcher (E.C.). The colour of the cohesive bandage, the IceTag identification number and time of the IceTag activation were recorded at the beginning of the 48 h observation period by the researcher (E.C.). 2ff7e9595c
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