Constrained Optimization Based on Hybridized Version of Superiority of Feasibility Solution Strategy

Teaching learning based optimization (TLBO) is a stochastic algorithm which was first proposed for unconstrained optimization problems. It is population based, nature-inspired, and meta-heuristic that imitates teaching learning process. It has two phases, teacher and learner. In teacher phase, the teacher who is well-learned person transfers his/her knowledge to the learners to raise their grades/results; while in learner phase, learners/pupils learn and refine their knowledge through mutual interconnection. To solve constrained optimization problems (COPs) through TLBO we need to merge it with some constraint handling technique (CHT). Superiority of feasibility (SF) is a concept for making CHTs, existed in different forms based on various decisive factors. Most commonly used decision making factors in SF are number of constraints violated (NCV) and weighted mean (WM) values for comparing solutions. In this work, SF based on number of constraints violated (NCVSF) and weighted mean (WMSF) are incorporated in the framework of TLBO. These are tested upon CEC-2006 constrained suit with the remark that single factor used for the decision making of winner is not a wise idea. Mentioned remark leads us to made a single CHT that carries the capabilities of both discussed CHTs. It laid the foundation of hybrid superiority of feasiblity (HSF); where NCV and WM factors are combined with giving dominance to NCV over WM. In current research three constrained versions of TLBO are formulated by the name NCVSF-TLBO, WMSF-TLBO, and HSF-TLBO; while implanting NCVSF, WMSF, and HSF in the framework of TLBO, respectively. These constrained versions of TLBO are evaluated on CEC-2006 with the remarks that HSF-TLBO got prominent and flourishing status among these.

Phenotypic plasticity and developmental noise in hybrid and parental clones of Daphnia longispina complex

According to the “temporal hybrid superiority hypothesis”, seasonal variability in environmental factors in temperate lakes gives hybrid clones within the D. longispina complex a temporary fitness advantage, thus allowing long-term, dynamic coexistence of hybrids and maternal taxa. However, the maintenance of hybrids would not require their superiority under any given set of environmental conditions if their average fitness over longer periods surpassed that of more specialized and less flexible parental clones. Phenotypic plasticity and developmental noise of several hybrid and maternal clones of Daphnia (Daphnia galeata, Daphnia hyalina, their hybrids and backcrosses) were compared in a series of laboratory experiments. Changes in depth selection and body size at first reproduction were scored in Daphnia exposed to predator (planktivorous fish) threat, to the presence of filamentous cyanobacteria (Cylindrospermopsis raciborskii), and to the presence of toxic compounds (PCB52 and PCB153). The hybrid clones were found to exhibit the broadest phenotypic plasticity of the studied traits in response to the different stress factors. Developmental noise in depth selection behaviour was the lowest in Daphnia galeata, the highest in Daphnia hyalina, and intermediate in hybrid and backcross clones. This diversity of reaction norms might permit the coexistence of closely related Daphnia clones in the variable and often unpredictable lake environment.

STUDY OF THE RAPHANUS SATIVUS L. (SMALL RADISH) BIODIVERSITY UNDER CONDITIONS OF INTENSIVE LIGHT-CULTURE AND IDENTIFICATION OF DONORS OF ECONOMICALLY LUABLE CHARACTERS FOR BREEDING

Supply of the domestic fresh vegetables commodity to the population of Northern regions of Russia is one of the most priority tasks of the national economy. Lack of the local, high-quality and adopted breeding material is highly problematic for breeding programs. Generation of the new, highly productive vegetable cultivars for the glass-covered ground, including light culture, will promote to expand significantly the volume of local production of vegetables in protected ground, especially in regions with a cold climate. One of the most prospective crops for protected ground is small radish, an early ripening crop with a valuable biochemical composition. А strategy for creation of the new, highly productive forms of small radish, beard predictable complex of economically valuable characters for growing in conditions of intensive light culture, has been developed in the Agrophysical Research Institute (SaintPetersburg). At the first stage, represent interspecific set of 26 small radish cultivars from different regions, was investigated in controlled conditions (artificial light, climate cell) to reveal a complex of economically valuable properties (early maturity, productivity, morphological traits). The plants were grown in original plant grooving light equipment (lamps DNaZ-400, photoperiod 12 hours, irradiation 15-20 klk), in a small volume of substrate (peat with mineral additives). It was observed that the small radish varieties have significant diversity in precocity, productivity, resistance to bolting, also they vary in a number of morphological features of roots and leaves. Bov, Estella, Rocco (Netherlands), Nobo Chind Criollo (Peru) were the most productive cultivars. They can produce yield of commercial roots during 30 days of vegetation up to 3.5 kg/m2. In addition, cultivars – genetic resources of economically valuable properties (compact rosette, glabrous leaf, resistance to bolting) were revealed for a breeding. Parent pairs for crossing were selected. It is planned to obtain offspring small radish forms with a complex of economically valuable properties, more productive than the parents. In all matched hybrid combinations, F1 hybrids were obtained. They have a degree of hybrid superiority in roots weight from 110 to 230% over the best of the parent form. They will become the ancestors of the original forms of small radish, intended for cultivation in conditions of intense light culture.