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1.
Heliyon ; 9(12): e22159, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125413

RESUMO

Recent studies have acknowledged the contribution of digital platforms to entrepreneurial activity. However, little has been discovered regarding the way digital platforms impact new start-ups' performance and how strategy affects this relationship. This study investigated this phenomenon using a structural equation model based on entrepreneurial bricolage and environmental strategy performance theory. The current findings indicate that broader market outreach, cost-effectiveness, and network effect produce a favorable, direct, and substantial effect on new startup performance. Furthermore, strategy moderates the effects of broader market outreach, network effect, and cost-effectiveness on new startup performance. Furthermore, strategy moderates the impact of broader market outreach, network effect, and cost-effectiveness on new startup performance. The Chinese government in particular, and governments of various emerging nations generally, must pay close attention to the results of this research to design policies that will not only lengthen the lifespan of small businesses but also promote rapid expansion as well as innovation of digital start-ups.

2.
J Sci Food Agric ; 99(1): 269-280, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29851100

RESUMO

BACKGROUND: Assessment of the different desirable characters among chili genotypes has expanded the effective selection for crop improvement. Identification of genetically superior parents is important in assortment of the best parents to develop new chili hybrids. RESULTS: This study was done to assess the hereditary assorted variety of selected genotypes of Capsicum annuum based on their morphophysiological and yield traits in two planting seasons. The biochemical properties, capsaicinoid content (capsaicin and dihydrocapsaicin), total phenolics content and antioxidant action determination of unripe and ripe chili pepper fruits were carried out in dry fruits. AVPP9813 and Kulai 907 were observed to have high fruit yields, with 541.39 and 502.64 g per plant, respectively. The most increased genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were shown by the fruit number per plant (49.71% and 66.04%, respectively). High heritability was observed in yield characters viz-à-viz fruit weight, length and girth and indicated high genetic advance. Eight groups were obtained from the cluster analysis. For the biochemical analysis, the capsaicinoid content and total phenolic content were high in Chili Bangi 3 at unripe and ripe fruit stages, while for antioxidant activity SDP203 was the highest in ripe dry fruit. CONCLUSION: Higher GCV and PCV, combined with moderate to high heritability and high hereditary progress, were seen in number of fruit per plant, fruit yield per plant and fruit weight per fruit. These findings are beneficial for chili pepper breeders to select desirable quantitative characters in C. annuum in their breeding program. © 2018 Society of Chemical Industry.


Assuntos
Capsicum/genética , Frutas/química , Frutas/crescimento & desenvolvimento , Variação Genética , Capsaicina/análogos & derivados , Capsaicina/análise , Capsicum/química , Capsicum/classificação , Capsicum/crescimento & desenvolvimento , Frutas/classificação , Frutas/genética , Genótipo , Fenóis/análise , Extratos Vegetais/análise
3.
Int J Mol Sci ; 19(10)2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30314374

RESUMO

Chili anthracnose is one of the most devastating fungal diseases affecting the quality and yield production of chili. The aim of this review is to summarize the current knowledge concerning the chili anthracnose disease, as well as to explore the use of marker-assisted breeding programs aimed at improving anthracnose disease resistance in this species. This disease is caused by the Colletotrichum species complex, and there have been ongoing screening methods of chili pepper genotypes with resistance to anthracnose in the field, as well as in laboratories. Conventional breeding involves phenotypic selection in the field, and it is more time-consuming compared to molecular breeding. The use of marker-assisted selection (MAS) on the basis of inheritance, the segregation ratio of resistance to susceptibility, and the gene-controlling resistance may contribute to the development of an improved chili variety and speed up the selection process, while also reducing genetic drag in the segregating population. More importantly, by using molecular markers, the linkage groups are determined dominantly and co-dominantly, meaning that the implementation of a reliable method to produce resistant varieties is crucial in future breeding programs. This updated information will offer a supportive direction for chili breeders to develop an anthracnose-resistant chili variety.


Assuntos
Capsicum/microbiologia , Colletotrichum , Resistência à Doença/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Capsicum/química , Suscetibilidade a Doenças , Marcadores Genéticos , Interações Hospedeiro-Patógeno , Fenótipo , Característica Quantitativa Herdável
4.
Cell Stress Chaperones ; 23(2): 223-234, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28812232

RESUMO

Backcrossing together with simple sequence repeat marker strategy was adopted to improve popular Malaysian chilli Kulai (Capsicum annuum L.) for heat tolerance. The use of molecular markers in backcross breeding and selection contributes significantly to overcoming the main drawbacks such as increase linkage drag and time consumption, in the ancient manual breeding approach (conventional), and speeds up the genome recovery of the recurrent parent. The strategy was adopted to introgress heat shock protein gene(s) from AVPP0702 (C. annuum L.), which are heat-tolerant, into the genetic profile of Kulai, a popular high-yielding chilli but which is heat sensitive. The parents were grown on seed trays, and parental screening was carried out with 252 simple sequence repeat markers. The selected parents were crossed and backcrossed to generate F1 hybrids and backcross generations. Sixty-eight markers appeared to be polymorphic and were used to assess the backcross generation; BC1F1, BC2F1 and BC3F1. The average recipient allele of the selected four BC1F1 plants was 80.75% which were used to produce the BC2F1 generation. BC1-P7 was the best BC1F1 plant because it had the highest recovery at 83.40% and was positive to Hsp-linked markers (Hsp70-u2 and AGi42). After three successive generations of backcrossing, the average genome recovery of the recurrent parent in the selected plants in BC3F1 was 95.37%. Hsp gene expression analysis was carried out on BC1F1, BC2F1 and BC3F1 selected lines. The Hsp genes were found to be up-regulated when exposed to heat treatment. The pattern of Hsp expression in the backcross generations was similar to that of the donor parent. This confirms the successful introgression of a stress-responsive gene (Hsp) into a Kulai chilli pepper variety. Furthermore, the yield performance viz. plant height, number of fruits, fruit length and weight and total yield of the improved plant were similar with the recurrent parent except that the plant height was significantly lower than the Kulai (recurrent) parent.


Assuntos
Capsicum/genética , Genes de Plantas , Proteínas de Choque Térmico HSP70/genética , Endogamia , Regulação da Expressão Gênica de Plantas , Marcadores Genéticos , Técnicas de Genotipagem , Proteínas de Choque Térmico HSP70/metabolismo , Heterozigoto , Repetições de Microssatélites/genética , Polimorfismo Genético
5.
Biotechnol Genet Eng Rev ; 33(1): 26-39, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28649918

RESUMO

Studying the strategies of improving abiotic stress tolerance is quite imperative and research under this field will increase our understanding of response mechanisms to abiotic stress such as heat. The Hsp70 is an essential regulator of protein having the tendency to maintain internal cell stability like proper folding protein and breakdown of unfolded proteins. Hsp70 holds together protein substrates to help in movement, regulation, and prevent aggregation under physical and or chemical pressure. However, this review reports the molecular mechanism of heat shock protein 70 kDa (Hsp70) action and its structural and functional analysis, research progress on the interaction of Hsp70 with other proteins and their interaction mechanisms as well as the involvement of Hsp70 in abiotic stress responses as an adaptive defense mechanism.


Assuntos
Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP70/metabolismo , Sítios de Ligação , Fenômenos Fisiológicos Vegetais , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Ligação Proteica , Estresse Fisiológico
6.
J Sci Food Agric ; 97(4): 1164-1171, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27290898

RESUMO

BACKGROUND: Studies on genotypic and phenotypic correlations among characters of crop plants are useful in planning, evaluating and setting selection criteria for the desired characters in a breeding program. The present study aimed to estimate the phenotypic correlation coefficients among yield and yield attributed characters and to work out the direct and indirect effects of yield-related characters on yield per plant using path coefficient analysis. Twenty-six genotypes of chili pepper were laid out in a randomized complete block design with three replications. RESULTS: Yield per plant showed positive and highly significant (P ≤ 0.01) correlations with most of the characters studied at both the phenotypic and genotypic levels. By contrast, disease incidence and days to flowering showed a significant negative association with yield. Fruit weight and number of fruits exerted positive direct effect on yield and also had a positive and significant (P ≤ 0.01) correlation with yield per plant. However, fruit length showed a low negative direct effect with a strong and positive indirect effect through fruit weight on yield and had a positive and significant association with yield. CONCLUSION: Longer fruits, heavy fruits and a high number of fruits are variables that are related to higher yields of chili pepper under tropical conditions and hence could be used as a reliable indicator in indirect selection for yield. © 2016 Society of Chemical Industry.


Assuntos
Cruzamento , Capsicum/genética , Frutas/crescimento & desenvolvimento , Genótipo , Fenótipo , Melhoramento Vegetal , Clima Tropical , Agricultura , Biomassa , Capsicum/crescimento & desenvolvimento , Flores , Desenvolvimento Vegetal , Doenças das Plantas
7.
ScientificWorldJournal ; 2014: 308042, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25478590

RESUMO

High temperature tolerance is an important component of adaptation to arid and semiarid cropping environment in chili pepper. Two experiments were carried out to study the genetic variability among chili pepper for heat tolerance and morphophysiological traits and to estimate heritability and genetic advance expected from selection. There was a highly significant variation among the genotypes in response to high temperature (CMT), photosynthesis rate, plant height, disease incidence, fruit length, fruit weight, number of fruits, and yield per plant. At 5% selection intensity, high genetic advance as percent of the mean (>20%) was observed for CMT, photosynthesis rate, fruit length, fruit weight, number of fruits, and yield per plant. Similarly, high heritability (>60%) was also observed indicating the substantial effect of additive gene more than the environmental effect. Yield per plant showed strong to moderately positive correlations (r = 0.23-0.56) at phenotypic level while at genotypic level correlation coefficient ranged from 0.16 to 0.72 for CMT, plant height, fruit length, and number of fruits. Cluster analysis revealed eight groups and Group VIII recorded the highest CMT and yield. Group IV recorded 13 genotypes while Groups II, VII, and VIII recorded one each. The results showed that the availability of genetic variance could be useful for exploitation through selection for further breeding purposes.


Assuntos
Capsicum/genética , Frutas/genética , Variação Genética , Estresse Fisiológico/genética , Cruzamento , Capsicum/fisiologia , Frutas/fisiologia , Genótipo , Temperatura Alta
8.
Molecules ; 19(5): 6474-88, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24853712

RESUMO

Research was carried out to estimate the levels of capsaicin and dihydrocapsaicin that may be found in some heat tolerant chili pepper genotypes and to determine the degree of pungency as well as percentage capsaicin content of each of the analyzed peppers. A sensitive, precise, and specific ultra fast liquid chromatographic (UFLC) system was used for the separation, identification and quantitation of the capsaicinoids and the extraction solvent was acetonitrile. The method validation parameters, including linearity, precision, accuracy and recovery, yielded good results. Thus, the limit of detection was 0.045 µg/kg and 0.151 µg/kg for capsaicin and dihydrocapsaicin, respectively, whereas the limit of quantitation was 0.11 µg/kg and 0.368 µg/kg for capsaicin and dihydrocapsaicin. The calibration graph was linear from 0.05 to 0.50 µg/g for UFLC analysis. The inter- and intra-day precisions (relative standard deviation) were <5.0% for capsaicin and <9.9% for dihydrocapsaicin while the average recoveries obtained were quantitative (89.4%-90.1% for capsaicin, 92.4%-95.2% for dihydrocapsaicin), indicating good accuracy of the UFLC method. AVPP0705, AVPP0506, AVPP0104, AVPP0002, C05573 and AVPP0805 showed the highest concentration of capsaicin (12,776, 5,828, 4,393, 4,760, 3,764 and 4,120 µg/kg) and the highest pungency level, whereas AVPP9703, AVPP0512, AVPP0307, AVPP0803 and AVPP0102 recorded no detection of capsaicin and hence were non-pungent. All chili peppers studied except AVPP9703, AVPP0512, AVPP0307, AVPP0803 and AVPP0102 could serve as potential sources of capsaicin. On the other hand, only genotypes AVPP0506, AVPP0104, AVPP0002, C05573 and AVPP0805 gave a % capsaicin content that falls within the pungency limit that could make them recommendable as potential sources of capsaicin for the pharmaceutical industry.


Assuntos
Capsaicina/análogos & derivados , Capsaicina/análise , Capsicum/química , Capsicum/genética , Cromatografia Líquida/métodos , Calibragem , Genótipo , Limite de Detecção , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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