Determining an effective and economic fungicide spray schedule for reducing blast of wheat

Wheat blast, caused by the fungus Magnaporthe oryzae pathotype Triticum (MoT), constitutes one of the major obstacles to the expansion of wheat production in Bangladesh. In the absence of resistant variety, fungicide control is the first-hand effort. Determining an effective and economic fungicide spray schedule in controlling blast disease of wheat was aimed. Ten fungicides were tested during two consecutive cropping seasons of 2018-2019 to 2019-2020. The wheat plants of blast susceptible cultivar BARI Gom 26 were inoculated with spores (107 spores ml-1) of MoT at pre-heading stage of wheat (52 days age). Fungicides were applied both before inoculation and after the appearance of blast symptoms in cocktail for three times starting from booting of wheat at 7 days interval. Plants received the combination of Filia (Tricyclazole 40% + Propiconazole 12.5%) and Seltima (Pyraclostrobin 10%) had significantly lower blast incidence and severity (1.23% and 3.33%) against untreated plants. Cocktail of Nativo and Trooper (Tricyclazole 75 wp) proved 2nd best curative measure. Application of Nativo (Tebuconazole 50% + Trifloxystrobin 25%) alone ranked third in its efficacy. The fungicide spray schedule covered booting, pre-heading and heading stages of wheat. The results indicate a mixture of Tebuconazole + Tricyclazole + Pyraclostrobin is more effective (97% blast reduction) and economic (BCR 1.45) than a single compound application in reducing incidence and severity of wheat blast. Int. J. Agril. Res. Innov. Tech. 11(1): 10-16, June 2021

Robust Stabilization of Interval Plants with Uncertain Time-Delay Using the Value Set Concept

This paper considers the robust stabilization problem for interval plants with parametric uncertainty and uncertain time-delay based on the value set characterization of closed-loop control systems and the zero exclusion principle. Using Kharitonov’s polynomials, it is possible to establish a sufficient condition to guarantee the robust stability property. This condition allows us to solve the control synthesis problem using conditions similar to those established in the loopshaping technique and to parameterize the controllers using stable polynomials constructed from classical orthogonal polynomials.

Physiological Growth Attributes, Productivity, Chemical Quality of the Fruits of Physalis peruviana Under a Foliar Mineral Supplementation

This work aimed to evaluate the influence of the interval of additional fertilizers on growth, productivity and quality of the fruits of Physalis peruviana. Plants were subjected to the treatments: no supplementary foliar fertilizing; weekly interval of supplementary foliar fertilizing and biweekly interval of supplementary foliar fertilizing. Growth, productivity and quality after harvest were analyzed. Plants under weekly interval of supplementary foliar fertilizing presented a higher leaf area and harvest index, however, under biweekly interval, plants presented higher productivity and fruit quality.