جستجوی مقالات مرتبط با کلیدواژه « Desirability index » در نشریات گروه « کشاورزی »

More specifically, the excessive use of inorganic fertilizers has reduced yield and nutrients efficiency of use and intensified nutrient losses in agroecosystems. Optimization is a modelling techniques approach to improve nutrient efficiency of use and mitigate environmental losses. Response surface methodology (RSM) is a statistical technique which is widely used in engineering and scientific disciplines to optimize processes and improve product quality. George Box and his colleagues developed response surface methodology (RSM) during the 1950s. The combination of experimental design, modeling techniques, and optimization methods in response surface methodology (RSM) provides a robust approach that leverages experimental data to achieve process improvements. The experimental design phase of RSM involves planning and conducting experiments to generate data that can be used to build a mathematical model of the relationship between the process parameters and the response variable(s) of interest. In this study, the optimization of cow manure and sulfate potassium fertilizers as two effective fertilizers in saffron production on yield, yield components of flower and corms of saffron was evaluated by using RSM. 

An experiment was conducted with 13 treatments and two replications at the Agricultural Research Field, Ferdowsi University of Mashhad, during two growing seasons of 2017-2018 and 2018-2019. The treatments were allocated based on low and high levels of cow manure (0 and 100 t. ha-1, respectively) and sulfate potassium (0 and 400 kg per ha, respectively). Flower yield indicators (such as fresh weight of flower, flower numbers and dried weight of stigma per unit) and daughter corm criteria (including daughter corm numbers per unit, dried weight of daughter corms per unit and daughter corm diameter) in the second year of experiment were computed as dependent variables and changes of these variables were evaluated by a regression model. The adequacy of the model was judged using analysis of variance, lack-of-fit test, determination coefficient (R2) and root mean square error (RMSE). Finally, the optimum levels of cow manure and potassium sulfate were calculated based on economic scenario for dependent variables such as stigma yield, daughter corm yield and daughter corm diameter and desirability index (D). 

The experimental results revealed that the effect of linear component was significant on flower numbers, fresh weight of flower and daughter corm diameter. Effect of square component was significant on flower numbers and fresh weight of flowers. Interaction effect of full quadratic component was significant on dried weight of daughter corms. Lack-of-fit test had no significant effect on the studied traits that represent the full square model was satisfactorily explained. The maximum observed values for fresh weight of flower and flower numbers were recorded for 100 t cow manure per ha+ without any potassium sulfate consumption with 15.15 g. m-2 and 33 flowers. m-2, respectively. The highest dried weight of daughter corms was observed in 100 t cow manure per ha+ 400 kg potassium sulfate per ha with 314.28 g. m-2. The estimated optimization rates for manure and potassium sulfate were 80.50 t. ha-1 and 371.71 kg. ha-1 (with D= 0.98), respectively. 

RSM is defined as a collection of statistical techniques that are used to optimize production inputs. RSM involves the design and analysis of experiments, modeling techniques, and optimization methods to find the optimal combination of process parameters that will yield the highest quality product or process output. The optimization phase involves using the mathematical model to identify the optimal process parameters that will yield the desired response variable(s). One of the key advantages of RSM is that it enables engineers and scientists to optimize complex processes with multiple input variables. RSM can also help reduce the number of experiments required to optimize a process, which can save time and resources. Additionally, RSM can help identify the interactions between different process parameters, which is useful for gaining a deeper understanding of the underlying process and for making further process improvements. Results demonstrate that for each response, different parameters and interactions were important. Therefore, to optimize parameters (such as cow manure and sulfate potassium), corm yield and stigma yield should be considered simultaneously. In general, it seems that optimization of resource use based on response-surface methodology may be suitable cropping approach for sustainable production, yield improvement and mitigation of environmental pollution in saffron cultivation.

In order to determine the desirability based on the qualitative and quantitative traits of the fruit, 11 cultivars of apple spore type along with control cultivar Golden Delicious were used. These cultivars were evaluated in Kamalshahr Horticultural Research Station of Karaj during two crop years (2011–2012) in a randomized complete blocks design with three replications and fruit related traits including fruit weight, fruit length, fruit diameter, fruit firmness, acidity percentage, TSS, fruit yield, fruit–set % and number of fruits per tree were recorded during two years. Combined analysis of variance showed that the effect of year was significant only for fruit diameter and fruit weight at the probability level of 5 % (P≤0.05). The effect of cultivar on all traits, except fruit–set %, was significant at the probability level of 1% (P≤0.01). The highest fruit yield was observed in Yellowspur cultivar with a value of 23.39 kg per tree. Using specific scores as the weight of traits, adjusted selection index of ideal genotype (ASIIG) was calculated and it was observed that Yellowspur cultivar with an index value of 78.16 % similar to the ideal genotype has the highest desirability among the cultivars and Yellowspur along with Golden Smoothie and Deliciousspur cultivars were more desirable than Golden Delicious cultivar. The graphs obtained from the adjusted selection index of ideal genotype with appropriate grouping of experimental cultivars identified only Yellow spur cultivar as a completely desirable cultivar.

The purpose of this experiment, evaluation of cow manure and irrigation levels on flower and corms of saffron using Central Composite Design was done with 13 treatments and two replications at the Research Field of the Ferdowsi University of Mashhad during two growing seasons of 2017-2018 and 2018-2019. The treatments were based on low and high cow manure levels (0 and 80 t.ha-1, respectively) and water (120 and 50 percent of water requirement, respectively). The results showed that the linear component's effect was significant on (p≤0.05) daughter corm diameter and numbers of daughter corms for 4-8 g. The square component's effect was significant on (p≤0.05) flower number, fresh weight of flower, the dried weight of stigma, and daughter corm diameter. The interaction effect of full quadratic was significant (p≤0.05) on the dried weight of daughter corms. Lack of fit test had no significant effect on the studied traits. The response variables' full square model gave insignificant lack-of-fit, indicating that the data were satisfactorily explained. The highest values of dried weight of stigma, fresh weight of flower, and flower number were observed for 16 t cow manure per ha+ 5440 m3 water per ha (with, respectively 0.65 and 27.75 g.m-2and 60 No.m-2). The maximum amount for dried weight of daughter corms was observed for 32 t cow manure per ha+ 3200 m3 water per ha (with 4463.31 g.m-2). It is necessary to use 4693.33 m3 water per ha 30.12 t cow manure per ha to obtain optimum conditions under the economic scenario (with desirability index= 0.72).