biotic factors
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Indigenous technical knowledge (ITK) is the actual knowledge of a given population that reflects the experiences based on tradition and includes more recent experiences with modern technologies. Traditionally, farmers have used traditional knowledge to understand weather and climate patterns in order to make decisions about crop and irrigation cycles. This knowledge has been gained through many decades of experience and has been passed on from previous generations. The present study was undertaken with the objective of collection and documenting the indigenous technical knowledge of farmers regarding rainfall prediction based on abiotic and biotic factors which is being practiced generation after generation. Here in this paper an effort has been made to collect the abiotic and biotic factors predicting rainfall, as a part of ICAR sponsored NASF ad-hoc research project entitled “Developing climate resilient adaptive strategies for empowerment of farmers” which has been implemented in University of Agricultural Sciences, Dharwad from 2019 to 2022. Various indigenous technical knowledge are collected by analyzing the journals and newsletters, deep interaction with the farmers of study area, contacting the local resource persons and documenting oral histories without scientific validation. The study found that traditional methods of rainfall forecasting can be utilized for the purpose of short-term and long-term seasonal rainfall predictions by local communities. All available abiotic and biotic indigenous rainfall forecasting techniques may serve as alternative to modern technologies.

The paper describes the composition of introduced species that form the collection fund of the Dendrological Park «Askania Nova», groups of arboreal plants are identified in connection with their ecological resistance. Information about the influence of abiotic and biotic factors on plant life is given, pest-resistant species are proposed for use. The tendencies of transformation of phytocenotic structure of the old park' s stands are noted. The directions of work on preservation of collection plantations and rare plants of different protection levels are described.

Sweet potato (Ipomoea batatas L., Lam.) is one of the most frequently eaten food crops. Its production is affected by plant-parasitic nematodes as well as biotic factors. This study was conducted to document the different plant-parasitic nematodes (PPN) that limit the gainful production of sweet potato in Gombe State. Thirty soil core samples per hectare were collected at random from sweet potato farms in the three local government areas (Nafada, Kaltungo, and Yamaltu Deba) of Gombe state. The Whitehead and Hemming method and identification keys were used for the soil extraction and genera identification of the plant-parasitic nematodes respectively. A total of 15 plant-parasitic nematodes were recovered throughout the surveyed areas among which 7 are considered major nematode pests of global importance. Irrespective of the surveyed locations, Meloidogyne spp., was found to record the highest population density and prevalence value. The frequency of occurrence in Y/Deba and Nafada LGAs shows that Meloidogyne spp., wasthe most occurring (32 %) genera. In Kaltungo LGA however, Scutellonema spp., and Rotylenchusspp., were the most occurring (17 %) genera. There was a high similarity percentage (≥ 68 %) of PPN genera where 8 genera (Scutellonema spp., Nacobbus spp., Pratylenchus spp., Meloidogyne spp., Heterodera spp., Xiphinema spp., Trichodorus spp., and Rotylenchus spp.) were found to be common amongst the surveyed locations. This is the first report of plant-parasitic nematodes associated with sweet potato in Gombe state, Nigeria. Hence, it is critical to educate farmers in the regions about their effects on the crop and how to successfully manage them.

It is still to be confirmed whether global warming with its predicted elevated water temperature will cause an increase in predation and alter phenological and physiological processes leading to changes in the size of aquatic organisms. In an experimental system of water column stratification simulating a natural combination of field conditions, we created artificial abiotic factors that mimicked the natural environment, i.e., light intensity, oxygen conditions, and thermal stratification. Subsequently, we added biotic factors such as algae, Daphnia, and planktivorous fish. We studied the intensity of foraging of planktivorous fish on individuals of Daphnia per min in different conditions of biotic and abiotic gradients. We demonstrated a possible scenario involving the risk of elimination of large prey within macrocladocera communities by predatory pressure as a result of climate change. A higher intensity of foraging of planktivorous fish caused or increased the occurrence of larger groups of planktonic animals with a smaller body size. The mechanisms of a future scenario were discovered at a higher trophic level in the aquatic environment.

<p>A population with an adequate immunity is key to reduce the effects of COVID-19. Moreover, a healthy diet and an innocuous environment are factors for an adequate immunity. Healthier and more innocuous foods could be obtained with the extensive use of beneficial organisms on agricultural crops, helping reduce the use of agrochemicals and increasing the tolerance of plants to stress caused by abiotic and biotic factors. Nitrogen-fixating bacteria or free-living bacteria, mycorrhizae, endosymbiotic microorganisms, endophytes, entomopathogenic fungi and bacteria, pest predators and parasitoids, hyper parasitic viruses of pests and pathogens are some of the organisms that can induce the natural suppression of parasites, fixate nitrogen and optimize the capture of nutrients and water, among other ecosystemic benefits. This revision presents functions and properties of beneficial organisms and proposals are made for their use to benefit farmers and consumers, with the intention of contributing to the productive processes towards a sustainable agriculture.</p>

How and why lineages evolve along niche space as they diversify and adapt to different environments is fundamental to evolution. Progress has been hampered by the difficulties of linking a comprehensive empirical characterization of species niches with flexible evolutionary models that describe their evolution. Consequently, the relative influence of external episodic and biotic factors remains poorly understood. Here we characterize species' two-dimensional temperature and precipitation niche space occupied (i.e., species niche envelope) as complex geometries and assess their evolution across a large vertebrate radiation (all Aves) using a model that captures heterogeneous evolutionary rates on time-calibrated phylogenies. We find that extant birds coevolved from warm, mesic climatic niches into colder and drier environments and responded to the K-Pg boundary with a dramatic increase in disparity. Contrary to expectations of subsiding rates of niche evolution as lineages diversify, our results show that overall rates have increased steadily, with some lineages experiencing exceptionally high evolutionary rates, associated with colonization of novel niche spaces, and others showing niche stasis. Both competition- and environmental change-driven niche evolution transpire and result in highly heterogeneous rates near the present. Our findings share the limitations of all work based purely on extant taxa but highlight the growing ecological and conservation insights arising from the model-based integration of increasingly comprehensive and robust environmental and phylogenetic information.

Abstract Mosquitoes are vectors of several diseases of medical concern such as malaria or dengue and can also negatively affect tourism and the life-quality of the neighbourhood. The species Aedes mariae (Sergent and Sergent, 1903) is a poorly studied mosquito that breeds in rock-pools of the Mediterranean coast. General Linear Mixed Models (GLMM) were used to determine drivers affecting the presence and abundance of this species. Abiotic and biotic factors were recorded in rock-pools with the presence of Ae. mariae sub-adults across a supralittoral area of Majorca Island (Balearic Islands, Spain) from July 2018 to June 2019. We tested how abiotic factors affected the presence of larvae, while the biotic factors were used to check their effect on larvae abundance. human landing collection was also conducted to assess the adult activity of this species. Valuable data were recorded to improve our knowledge about the bioecology of Ae. mariae in a touristic area of the island of Majorca. Salinity and pH were the most explanatory variables for the presence of Ae. mariae larvae. The presence of Posidonia oceanica (L.) Delile 1813 leaves negatively affected the abundance of Ae. mariae larvae while the presence of other fauna enhanced it. Adult females of Ae. mariae were active for 26 min after sunset in June and its host-seeking activity decreased during autumn months. Control methods against this species should be focussed on rock-pools and planning treatments according to tides, waves and precipitation.

Plant phenology is manifested in the seasonal timing of vegetative and reproductive processes, but also has ontogenetic aspects. The adaptive basis of seasonal phenology has been considered mainly in terms of climatic drivers. However, some biotic factors as likely evolutionary influences on plants’ phenology appear to have been under-researched. Several specific cases of putative biotic factors driving plant phenology are outlined, involving both herbivores and pathogens. These illustrate the diversity of likely interactions rather than any systematic coverage or review. Emphasis is on woody perennials, in which phenology is often most multi-faceted and complicated by the ontogenetic aspect. The complete seasonal leaf fall that characterises deciduous plants may be a very important defence against some pathogens. Whether biotic influences drive acquisition or long-term persistence of deciduousness is considered. In one case; of leaf rusts in poplars, countervailing influences of the rusts and climate suggest persistence. Often, however, biotic and environmental influences likely reinforce each other. The timing and duration of shoot flushing may in at least some cases contribute to defences against herbivores, largely through brief periods of ‘predator satiation’ when plant tissues have highest food value. Wide re-examination of plant phenology, accommodating the roles of biotic factors and their interplays with environments as additional adaptive drivers, is advocated, towards developing and applying hypotheses that are observationally or experimentally testable.