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31.
Quintino Araujo Dario Ahnert Guilherme Loureiro José Faria Cinira Fernandes Virupax Baligar 《Archives of Agronomy and Soil Science》2018,64(13):1892-1909
The soil quality index (SQI) for cacao cropping systems was developed to meet the nutritional criteria of the crop, the environmental safety of the cropping sites and the increasing demand for the production and quality of cocoa. Available water function (AWF), root growth function (RGF), mineral nutrition of plants function (MNF) and environmental safety function (ESF) for potentially toxic elements were included in the additive model of SQI for cacao cropping systems. In this study, over 66% of the cacao fields cropping sites were classified as regular SQI with a range of scores between 0.42 and 0.61. The field cropping site with the highest score (0.73) characterized as typic Alitic Red-Yellow Argisol was rated with high SQI. In contrast, the field cropping sites characterized as abrupt Cohesive Dystrophic Red-Yellow Argisol (0.29), typic Dystrophic Haplic Cambisol (0.39), and latosolic Dystrophic Yellow Argisol (0.40) were rated with low SQI. MNF and AWF were the functions that most contributed to the increase or decrease of SQI scores. The SQI adapted expressed the agro-environmental reality of cacao cropping systems of Bahia, Brazil, and this could be a versatile tool to subsidize the adequate soil management of cacao plantations around the world. 相似文献
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Lúcia Cristina VriesmannRenata Dias de Mello Castanho Amboni Carmen Lúcia de Oliveira Petkowicz 《Industrial Crops and Products》2011,34(1):1173-1181
The composition of cacao pod husks (CPHs), the main waste product of cocoa production, and some of the characteristics of their water-soluble pectins were investigated. Milled and dried CPHs were submitted to hot aqueous extractions (50 and 100 ?C, 90 min, 1:25, w/v). The obtained fractions (labeled 50W and BW, respectively) yielded 7.5 and 12.6% pectins, respectively. The monosaccharide composition revealed the predominance of uronic acid, followed by galactose, rhamnose and arabinose, characteristic of pectins. Chemical and spectroscopic analyses (FT-IR and 13C NMR) showed that both fractions contained high acetyl contents (DA 29.0 and 19.2%, respectively) and are composed of low methoxyl homogalacturonans (DE 37.0 and 42.3%, respectively) with rhamnogalacturonan insertions carrying side chains containing mainly galactose. Rheological analyses were carried out with 50W and BW. Solutions of both fractions at 5% (w/v) had a non-Newtonian shear-thinning behavior, however that of 50W showed higher apparent viscosity than that of BW. Dynamic oscillatory analyses showed that 5% (w/w) 50W pectin had weak gel behavior whereas at the same concentration, BW pectin behaved as a concentrated solution. Although further investigations are required, CPH seems be a potential source of both pectins and other natural agents such as fibers and phenolics, and its use is particularly justified by growing environmental awareness. 相似文献
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研究椰子间作可可下的可可光合速率(Pn)和环境因子日变化,探讨间作可可Pn与环境因子的关系,为优化可可栽培技术提供理论依据。结果表明,间作和单作可可Pn日变化均呈双峰曲线,有光合“午休”现象。环境因子与Pn的相关性均不显著(p>0.05),间作和单作可可环境因子对Pn的直接作用均为TL>RH>PAR>Ta,对间作可可Pn的影响是PAR、TL和Ta等相互作用的结果。光合有效辐射是影响间作可可Pn的主要环境因子。在可可的栽培管理中,应发挥主导环境因子的作用。 相似文献
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Nowadays, consumers demand dietary fibre-enriched products of appropriate taste, texture, smell and appearance. Unfortunately, addition of the dietary fibre supplements to bread significantly reduces its quality which is connected with changes in the structure of gluten proteins. Structural changes as well as changes in the water state of gluten matrix induced by eight dietary fibres were observed by using Fourier transform infrared spectroscopy. To facilitate this the difference spectra were calculated by subtraction of the control (gluten only) infrared spectrum from the spectra of gluten-fibre mixtures. The presence of positive bands at ca. 1597 and 1235 cm−1 indicated aggregation of gluten proteins into hydrogen bonded β-sheets. These β-sheets can be formed by other β-sheets, antiparallel-β-sheets, β-turns and/or α-helices. The aggregation is probably induced by partial dehydration of gluten matrix due to competition for water molecules between gluten proteins and fibre polysaccharides. This assumption is confirmed by the presence of the negative band at 3237 cm−1 and decrease in the intensity of the band at 3051 cm−1. These bands are assigned to the weak and strong H-bonds in the gluten matrix, respectively. The results indicated that both weak and strong H-bonds are necessary to dough formation of adequate rheological properties. 相似文献
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M. A. Q. Ribeiro J. O. da Silva W. M. Aitken R. C. R. Machado V. C. Baligar 《Journal of plant nutrition》2013,36(2):239-249
Cacao (Theobroma cacao L) is mostly grown on soils with low natural fertility. On such soils nitrogen (N) is one of the most yield limiting nutrients for cacao. Information is lacking on N use efficiency in cacao. A greenhouse experiment was conducted to evaluate growth response and N use efficiency by two cacao genotypes. The genotypes used were TSH-565 and ICS-9 and N rates adapted were 0, 120, 240, 360, and 480 mg N /pot. In both genotypes, increasing levels of applied N improved growth (stem girth, dry weight of shoot and roots and shoot/root ratio), and concentration and uptake of N. Genotypes differed significantly for stem girth and ICS -9 produced greater stem girth compared with TSH-565. Nitrogen uptake had a linear relationship with root dry weight of the two genotypes. In both genotypes, increasing levels of applied N overall increased N-uptake efficiency (NEFF = N concentration in shoot x shoot/root), but decreased N-use efficiency by shoot and roots (NUE = g dry matter of shoot or root/mg N) and N-use efficiency of carbohydrate (NUEC = mg of total carbohydrates in shoot/mg of N in shoot). Both genotypes responded differently to applied N, despite the existence of close genetic relatedness between them. The method used here appears to be suitable method for identification of cacao genotypes that are efficient in uptake and utilization of N. 相似文献
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Wouter Vanhove Yan Feng Mengmeng Yu Ikhram Osman Hafiz Niels Vanhoudt Patrick L. J. Van Damme 《国际虫害防治杂志》2020,66(2):155-162
AbstractIn South-East Asia, cocoa production is dramatically affected by cocoa pod borer (CPB) infestations. As an alternative tool to chemical control, the efficacy of attract-and-kill strategy (CPB sex-pheromone as attractant and Delta trap without sticky liner sprayed with cypermethrin solution as killing station) was evaluated and compared with current standard CPB management approach as control treatment during two main cocoa harvest seasons in Malaysia (with 100 µg and 33.3 µg CPB-pheromone loading per station, respectively). In both seasons, attract-and-kill strategy was highly effective at reducing male flight activity (p?<?0.05) in attract-and-kill plots comparing with standard CPB management plots. For the percentage of CPB-infested pods, the attract-and-kill strategy (100 µg) was as good as the conventional pesticide spray applications of cypermethrin (p?=?0.083) in first season. However, it was significantly (p?=?0.021) reduced in the second season with lower pheromone loading (33.3 µg), indicating that this semiochemical based strategy is far superior to and more feasible than the currently applied conventional synthetic pesticide treatment and is therefore a good alternative in CPB integrated pest management. 相似文献
40.
Population structure and migration of the witches’ broom pathogen Moniliophthora perniciosa from cacao and cultivated and wild solanaceous hosts in southeastern Brazil 下载免费PDF全文
N. G. R. B. Patrocínio P. C. Ceresini L. I. S. Gomes M. L. V. Resende E. S. G. Mizubuti K. P. Gramacho 《Plant pathology》2017,66(6):900-911
Moniliophthora perniciosa, causal agent of witches’ broom disease in cacao plantations in South America and the Caribbean Islands, has co‐evolved with its host cacao, but the pathogen has also emerged in many solanaceous hosts in Brazil, including economically important food crops and wild species. This study was carried out to: (i) determine the existence of host subpopulations of M. perniciosa in Brazil; (ii) estimate gene and genotypic diversity of M. perniciosa host subpopulations infecting solanaceous hosts in southeastern Bahia and Minas Gerais states, Brazil; and (iii) estimate the amount and directionality of historical migration of M. perniciosa subpopulations. Up to 203 M. perniciosa isolates collected from solanaceous hosts with symptoms from Bahia and Minas Gerais states in Brazil and from Theobroma spp. (cacao) and Herrania spp. were characterized with 11 microsatellite markers. Factorial correspondence analyses, minimum‐spanning network and Bayesian clustering revealed genetic clusters associated with their host of origin. Significant subpopulation differentiation was evident (ΦST = 0.30, P ≤ 0.05) among M. perniciosa host subpopulations. Most of the multilocus microsatellite genotypes (MLMGs) were host‐specific, with few MLMGs shared among subpopulations. Pairwise comparisons among M. perniciosa host subpopulations were significant, except between jurubeba (Solanum paniculatum) and cultivated solanaceous subpopulations. The combined analyses rejected the null hypothesis that M. perniciosa in Brazil is a single genetic population not structured by host. These findings support a scenario of introduction and subsequent adaptation to solanaceous hosts that should be taken into consideration to improve mitigation and management of M. perniciosa. 相似文献