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Seed is a very good carrier of phytonematodes, especially for long distance dissemination. This transmission occurs either directly through seed infection or via seed contamination. Although in low rate, this transmission becomes a serious concern when trans-boundary movement of invasive alien nematode species flares up in epiphytotic proportion. Hence, detection and diagnosis of seed-borne and seed-associated nematode are significant for their protection. So far, various conventional methods are mostly employed for detection, but advancement of modern approaches, viz. serological or molecular techniques, speeds up the process with more accurate detection. Their robustness and specificity with greater resolution help in identification and discrimination of different species of seed-borne phytonematodes, thus strengthening phytosanitary programme and ensuring low risk in world trade. It also helps in pest risk analysis (PRA) of any pests having quarantine importance and development of national standards for import of seed and planting materials. Besides these, for the identification of pest-free area, production of certified seeds, and promotion of export quality raw plant products, detection of seed and seed-associated nematodes is very essential. Hence, detection is always considered as primary step for crop protection.

In this paper, a method of discrete decoupling and control of time-delayed MIMO systems s proposed. As to control the time-delayed MIMO plants in continuous domain, there is a requirement of the Pade approximation to rationalize the time-delayed MIMO plants. The Pade approximation technique may degrade the time domain performance of the MIMO systems. To avoid the Pade approximation, discrete-time approach is applied to decouple and control the time-delayed MIMO systems in which there will be no approximation required. Discrete-time PID controller is designed using bacterial foregoing optimization (BFO) technique. The proposed method is implemented to both square and non-square plants.

This paper presents the decoupling and control of the unstable MIMO systems. To design the decoupler for an unstable MIMO system, a state feedback method is adopted to stabilize the unstable MIMO system by placing the poles at the left half of s plane. After that, a decoupler is designed using generalized decoupling method for the stabilized transfer matrix of the MIMO systems. At last, the PID controller is designed for the decoupled MIMO system using Kharitonov’s theorem. A numerical example is considered to test the proposed method in MATLAB/Simulink. The simulation results obtained are found to be satisfactory for the proposed method.

This paper presents the design of proportional-integral-differential (PID) controller to control twin rotor multi-input multi-output system (TRMS). The TRMS is a nonlinear test rig associated with cross-coupling. Initially, a decoupling method is used in the linear model of TRMS to eliminate the effect of cross-coupling. Further, two PID controllers are designed by using three different optimization techniques: particle swarm optimization (PSO), real-coded genetic algorithm (RCGA), and bacterial foraging optimization (BFO) for the two resulting decoupled systems which, in turn, control the pitch and yaw motions. A relative interpretation conducted from the obtained responses in which it is recognized that responses of BFO optimized PID controller are superior.

At the present scenario, climate change became the potential threat to growers with rise in temperature, inconsistent rainfall, and salinization of agricultural land. However, the microbes more specifically plant growth-promoting rhizobacteria (PGPR) play a significant role to mitigate the abiotic stresses. Rhizobacteria act as bioprotectants against drought, salt, heavy metals, high temperature, and cold stress. During drought condition, PGPR intensifies osmolytes (proline, glycine, betaine) and acts as an osmoprotectant. The drought-related enzyme ACC deaminases were regulated by the PGPR, which also regulates the stomatal physiology during the water deficit conditions. The salt stress in plants was also a complex process to understand. During salt stress condition, PGPR acts as an activator of antioxidant enzymes and polyamines and also acts as a modulator of abscisic acid. Inoculation of PGPR affects the expression of 14 genes (four upregulated and two downregulated) related to salt stress. The effect of heavy metal toxicity is also found in plants, which is due to the improper fertilizer applications, industrial waste, sludge, etc. The main site for accumulation of heavy metals is the root nodule. At present many PGPR sp., i.e., Bacillus sp., Pseudomonas sp., Azotobacter sp., Enterobacter sp., and Rhizobium sp., were proposed to speed up the phytoremediation process of nodules. Bacterial metallothioneins (MTs) of the family Bmt, a family with low-molecular proteins, play a significant role to absorb heavy metals. High temperature also acts as a constraint of normal plant root nodulation and rhizobial growth. The strains of PGPRs evolve during the heat stress period against the raised temperature with the production of extra LPS, EPS, and special class of proteins, i.e., heat shock proteins (HSPs). Cold tolerance can also be derived by PGPR as the accumulation of more carbohydrate, regulation of stress-related genes for osmolytes expression, and enhancement of specific protein synthesis, which helps plant to fight against cold stress.

In the present work, H infinity \(\left( {H_{\infty } } \right)\) controller on the basis of linear matrix inequality is designed to control TRMS which is a nonlinear highly coupled system. A decoupler is appended to nullify the cross-coupling. The \(H_{\infty }\) controller designed for the decoupled system achieves robust performance even in presence of parametric uncertainty. Perturbations in the moment of inertia of main and tail rotor are considered as parametric uncertainties. The performance of the designed controller is inspected through simulation results in MATLAB/Simulink environment. The responses of the main and tail rotors are found to be adequate.