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Piracicaba, Brazil

Cardozo N.P.,Sugarcane Research Center | Sentelhas P.C.,University of Sao Paulo | Panosso A.R.,Sao Paulo State University | Ferraudo A.S.,Sao Paulo State University
Crop and Pasture Science | Year: 2014

Sugarcane ripening is a process controlled by cultivar characteristics and the interaction of genotypes with local climate. The objective of this study was to characterise the temporal variation of sugarcane ripening by assessing the multivariate structure contained in sugarcane quality data, and by correlating the results with local climatic conditions. Eight sugarcane cultivars were evaluated from March to October in Piracicaba, São Paulo State, Brazil. Characteristics related to the quality of raw sugarcane juice were submitted to statistical analysis by ANOVA, hierarchical and non-hierarchical (k-means) clustering methods, and principal components, in order to classify the cultivars into groups for each month of sampling. The ANOVA showed a clear difference (P<0.001) among harvesting months for all sugarcane quality variables, which was reinforced by the cluster analysis for the whole dataset that selected groups according to the month of harvest. By analysing the quality variables by months, patterns of similarity among sugarcane cultivars were identified, which allowed three ripening groups to be established: early, middle and late. As the harvesting season progressed, the variations within each group, as well as among groups, were explained mainly by local soil-water availability conditions. The early ripening cultivars showed polarisable sugar (Pol) values >13% in early May, whereas these values were reached by the middle cultivars in July, and the late ones in August-September. However, the differences among groups tended to decrease through the harvest season, as expressed by the Euclidean distance, which decreased from 5.62 in March to 1.82 in September, when the water deficit reached the maximum accumulated value, totalling >130mm. The non-hierarchical analyses (k-means) and principal components methods agreed, resulting in the identification of the same three main cultivar groups. The approach proposed for cultivar classification in this study is more complete than the usual analysis of Pol variation over time, since it allowed all of the variability contained in the sugarcane quality dataset to be analysed in an integrated way, providing a better understanding of the differences observed in the ripening of different cultivars. © CSIRO 2014. Source

Cardozo N.P.,Sugarcane Research Center | Bordonal R.D.O.,Sao Paulo State University | La Scala N.,Sao Paulo State University
Journal of Cleaner Production | Year: 2015

Irrigation increases sugarcane yield, especially in areas under restricted rainfall conditions. However, few studies have been carried out on the environmental impacts of this activity, mainly regarding greenhouse gas (GHG) emissions. Therefore, the aim of this study was to estimate the environmental impacts of sugarcane irrigation, contemplating GHG emissions at different production scenarios. For that, biomass production was simulated under rainfed conditions and different irrigation systems, comparing six Brazilian regions (Ribeirão Preto - SP; Araçatuba - SP; Paracatu - MG; Itumbiara - GO; Paranaíba - MS; and Petrolina - PE). After gathered, GHG emission estimates of each scenario were confronted with sugarcane production data. The results were expressed in "carbon (C) footprint" (kg CO2eq t-1). For all evaluated regions, irrigation intensifies and encumbers environmentally the agricultural practices by increasing GHG emissions (∼7447.0 kg CO2eq ha-1 yr-1) compared with rainfed condition (∼2154.6 kg CO2eq ha-1 yr-1). Irrigation systems require a large amount of electric power, diesel and other inputs such as synthetic nitrogen fertilizers. Surprisingly, this situation can change substantially if C footprint is considered. We observed that irrigated areas had a decrease C footprint of up to 59% (33.0 kg CO2eq t-1) against rainfed ones, as observed in Petrolina scenario. In other regions, C footprint reductions ranged from 23% (7.1 kg CO2eq t-1) in Ribeirão Preto to 37% (13.9 kg CO2eq t-1) in Paracatu. Thus, irrigated agriculture impact could be explored in terms of C footprint, which depends on regional biomass production as well as irrigation system efficiency towards a better water use. © 2015 Elsevier Ltd. Source

Saljoqi A.-U.-R.,Khyber Pakhtunkhwa Agricultural University | Zia Q.,Khyber Pakhtunkhwa Agricultural University | Gul F.,Sugarcane Research Center | Sadur-Rehman,Agricultural Research Institute
Pakistan Journal of Zoology | Year: 2012

Trichograma chilonis (Ishii) is an effective egg parasitoid of lepidopterous pests. It controls pests in eggs stage prior to its damaging to crop. The parasitoid is vulnerable to insecticides or oil sprays applied to the crops. The present study was intended to evaluate the compatibility of Jamama oil (Eruca sativa L.) with T. chilonis under the controlled laboratory conditions. Different Jamama oil concentrations i.e. 1.25, 1, 0.75, 0.5, 0.25% were tested on the different stages of T. chilonis. In pre-oviposition preference of T. chilonis experiment, all the studied parameters including percent parasitism, adult emergence and longevity were found significantly reduced while emergence time significantly increased by all the concentrations of Jamama oil as compared with the control. The results showed that the highest concentration of Jamama oil (1.25%) gave the minimum percent of parasitism, adult emergence and longevity (1, 0.75, 0.5 and 0.25% respectively). Lowest emergence time was recorded by utilizing the lowest concentration of Jamama oil (0.25%) followed by 0.5, 0.75, 1 and 1.25%, respectively. Same trend was also observed in all these parameters in post oviposition of T. chilonis in eggs stage, larval stage and pupal stage by utilizing the different concentration of Jamama oil. In the post oviposition of T. chilonis in adult stage, the highest concentration (1.25%) significantly reduced the adult longevity followed by the lower concentrations respectively. Highest longevity was recorded by using the lowest concentration of Jamama oil (0.5%). These studies showed that Jamama oil adversely affected percent parasitism, adult emergence, emergence time, and longevity of T. chilonis more in the preoviposition stage as compared with the post ovisposition stages of T. chilonis. Moreover, lowest concentrations of Jamama oil were found least toxic to T. chilonis and more effective in terms of percent parasitism, adult emergence, emergence time and longevity of T. chilonis. The results also showed that in the post oviposition stage of T. chilonis, in pupal stage the different concentrations of Jamama oil gave better results in all the studied parameters as compared to all other stages. This shows that Jamama oil can be combined more effectively with the T. chilonis in the pupal stage. Copyright © 2012 Zoological Society of Pakistan. Source

Ahmed A.O.,Sudan Sudanese Sugar Co. | Obeid A.,Sugarcane Research Center
African Journal of Agricultural Research | Year: 2010

The investigation was carried out at the Sugarcane Research Centre - Guneid (14, 48 -15.00° N) during the seasons 2003 - 04 and 2004 - 05. Twelve exotic sugarcane genotypes from Barbados, Guyana, Argentina and South India were tested in a randomized complete block design with four replicates. The objective was to quantify the genetic diversity among these genotypes regarding eleven cane yield and quality characters namely: stalk height, stalk diameter, internodal number per stalk; juice brix, juice pol, sugar recovery, juice purity, cane fiber and cane maturity percent, and yield of cane and sugar in Ton/hac. The results indicated that, the genotypes were grouped into six clusters based on the genetic distance using Mahalanobis's statistics. Higher inter-cluster distance was noticed between cluster IV and V (83.546) indicating high genetic diversity among two clusters. Thus, exploitation of genotypes within these two clusters as parents for crossing could produce good sugarcane segregants. The intracluster distance within cluster VI (7.226) and II (6.666) was very low indicating a close relationship of genotypes within each of these clusters. High cluster mean value for juice quality was recorded by cluster I whereas for cane and sugar yields, cluster VI was the best. It is suggested that genotypes within these two clusters could show greater potentiality for breeding purpose by virtue of their desirable characters. © 2010 Academic Journals. Source

Cardozo N.P.,Sugarcane Research Center | Sentelhas P.C.,University of Sao Paulo | Panosso A.R.,Sao Paulo State University | Palhares A.L.,Raizen Company | Ide B.Y.,Raizen Company
International Journal of Biometeorology | Year: 2015

The effect of weather variables on sugarcane ripening is a process still not completely understood, despite its huge impact on the quality of raw material for the sugar energy industry. The aim of the present study was to evaluate the influence of weather variables on sugarcane ripening in southern Brazil, propose empirical models for estimating total recoverable sugar (TRS) content, and evaluate the performance of these models with experimental and commercial independent data from different regions. A field experiment was carried out in Piracicaba, in the state of São Paulo, Brazil, considering eight sugarcane cultivars planted monthly, from March to October 2002. In 2003, at the harvest, 12 months later, samples were collected to evaluate TRS (kg t−1). TRS and weather variables (air temperature, solar radiation, relative humidity, and rainfall) were analyzed using descriptive and multivariate statistical analysis to understand their interactions. From these correlations, variables were selected to generate empirical models for estimating TRS, according to the cultivar groups and their ripening characteristics (early, mid, and late). These models were evaluated by residual analysis and regression analysis with independent experimental data from two other locations in the same years and with independent commercial data from six different locations from 2005 to 2010. The best performances were found with exponential models which considered cumulative rainfall during the 120 days before harvest as an independent variable (R2 adj ranging from 0.92 to 0.95). Independent evaluations revealed that our models were capable of estimating TRS with reasonable to high precision (R2 adj ranging from 0.66 to 0.99) and accuracy (D index ranging from 0.90 to 0.99), and with low mean absolute percentage errors (MAPE ≤ 5 %), even in regions with different climatic conditions. © 2015, ISB. Source

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