Agriculture
Surur Khorramdel; Fatemeh Moallem Banhangi; Javad Shabahang
Abstract
Optimization is one management approach to improve yield and resource efficiencies and decrease environmental pollutions in saffron agroecosystems. Response- surface methodology (RSM) is defined as a set of statistical techniques that are used to optimize a product. In this work, optimization of cow ...
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Optimization is one management approach to improve yield and resource efficiencies and decrease environmental pollutions in saffron agroecosystems. Response- surface methodology (RSM) is defined as a set of statistical techniques that are used to optimize a product. In this work, optimization of cow manure and leaf spraying with Dalfard on saffron using RSM was done. An experiment was conducted using central composite design with 13 treatments and two replications at the Agricultural Research Field of Ferdowsi University of Mashhad during two growing seasons of 2015-2016 and 2016-2017. The treatments were allocated based on low and high levels of cow manure (0 and 100 t.ha-1, respectively) and leaf spraying concentration with Dalfard ® (0 and 10 ppm, respectively). Flower yield, daughter corm yield and quality criteria were calculated as dependent variables and changes of these variables were evaluated by a regression model. Lack-of-fit test was used to evaluate the quality of the fitted model. The adequacy of the model was tested by analysis of variance. The quality of the fitted models was judged using the determination coefficient (R2). Finally, the optimum levels of cow manure and leaf spraying concentration were calculated based on economic scenario. The results showed that effect of linear component was significant on quality characteristics of stigma. Effect of square component was significant on dried weight of stigma, mean diameter of daughter corm, number of daughter corms per m2, mean weight of daughter corm and crocin content. Interaction effect of full quadratic component was significant on flower yield criteria. Lack of fit test had no significant effect on the studied traits that represent the full square model was satisfactorily explained. The maximum observed value for number of daughter corms was recorded for 50 t cow manure per ha+ no leaf spraying (with 41.38 corms.m-2). The highest observed value for dried stigma yield was related to 100 t cow manure per ha+ no leaf spraying (with 156.33 mg.m-2). The maximum observed amounts for quality criteria such as picrocrocin, crocin and safranal were calculated for 100 t cow manure per ha+ 10 ppm leaf spraying (with 89.91 E1%257, 180.98 E1%440 and 40.15 E1%330, respectively). Dried weight of stigma, number of daughter corms and crocin content were considered in economic scenario, so the estimated levels for cow manure and Dalfard concentration were 92.67 t/ha and 1.2 ppm, respectively. In general, it seems that resource use optimization based on Response- surface methodology may be suitable cropping approach for sustainable production and improvement of yield flower, corm yield and quality characteristics in saffron.
