Diversity of predatory spider fauna in maize ecosystem

Abstract

Investigations conducted on the identification of predatory spider fauna in maize ecosystem throughout the crop growth, in Tamil Nadu Agricultural University, Coimbatore during 2013-2014 yielded around 2821 spiders, belonging to 16 species under 10 genera of 6 families from seedling to maturity stage. Majority of the spiders collected belonged to the families Lycosidae (1671 individuals), Salticidae (459 individuals), Oxyopidae (352 individuals), Gnaphosidae (178 individuals), Corinnidae (96 individuals) and Clubionidae (65 individuals). The predatory spider species dominating in the maize ecosystem included the species Lycosa barnesi, L. pseudoannulata, Pardosa birmanica, Salticus sp. and Hippasa lycosina. Dendrogram analysis of spiders revealed that the families, Clubionidae and Gnaphosidae were closely related when compared to other predatory spider families. Correlation analysis with the weather parameters showed that the predatory spider population had non-significant positive correlation with relative humidity at 14:22 hrs and negative correlation with all other weather parameters viz., maximum temperature, minimum temperature, relative humidity at 07:22 hrs, rainfall, sunshine hours and rainy days.

Population Dynamics of Natural Enemies in Okra Agro-ecosystem in Relation to Abiotic Factors

“…The excessive use of nonrecommended chemical insecticides has been noticed for controlling the pest of okra by farming community which causes many serious problems to the environment, animals, human being and natural enemies [4]. The recent trends of agriculture are mainly focused on sustainable crop production and optimizing chemicals use, thus promoting the natural pest control agents by conservation of natural enemies [5]. Population of natural enemies are influenced by both host availability and abiotic factors.…”

“…Population of natural enemies are influenced by both host availability and abiotic factors. Among natural enemies spiders, ants and coccinellids are main predators that causes reduction of insect pests of okra [5]. Spiders are present in all agro-ecosystems and have significant influence on the pests of different crops [4] while in okra agro-ecosystem coccinellids are also found to play vital role in minimizing the pest population especially sucking pests [1].…”

Arthropod Biodiversity in Agricultural, Horticultural and Silvicultural Ecosystems with Special Reference to Spiders (Araneae) in Mid-hills of Meghalaya, India

“…Goswami et al (2015) found that Shannon diversity varied from 1.73-2.17, while Simpson index was between 0.13-0.18, Margelef richness index was found to be between 1.15-1.86, while Evenness index ranged between 0.69-0.72 at different growth stages of rice crop. Saranya et al (2019) found the species number (5-16), Fisher's Alpha (1.941-5.705), Margalef D (1.467-…”

“…Rajeswaran et al (2017) reported the families Oxyopidae and Lycosidae from maize ecosystem. Saranya et al (2019) reported the dominated families Salticidae, Lycosidae and Oxyopidae and the genera Pardosa, Lycosa and Hippasa from maize ecosystem. The present study repoeted maximum diversity in orb weavers (Araneidae and Tetraganthidae) which may be attributed to the robust growth and development of maize crop i.e.…”

Multivariate Analysis of Spider Diversity in Agricultural, Horticultural and Silvicultural Ecosystems and their Relation to Subtropical Climatic Conditions

“…The CCA ordination plot explains the occurrence of Arthropods in familial and ordinal level in horticultural ecosystems, in familial level CCA biplot explained total 92.95% of variation in which axis F1 and axis F2 explained 79.28% and 13.67% and in ordinal level CCA biplot explained total 94.43% of variation in which axis F1 and axis F2 explained 64.02% and 30.41% of relation between arthropod population and environmental parameters respectively (Table 4.3 Muhammad and Ahmed (2014) studied the seasonal abundance of soil arthropods in relation to meteorological and edaphic factors in the agroecosystems Viz., sugarcane, cotton, wheat, alfalfa and citrus orchards of Faisalabad, Punjab, Pakistan and used Bray-Curtis cluster analysis to study the soil arthropod based on similarity of abundance and found 4 different similarity cluster groups first cluster comprised of Collembola, Hymenoptera, Acarina, and Myriapoda (˃10%), second cluster composed of Orthoptera, Coleoptera, and Araneae (˃5%), third cluster Hemiptera, Dermaptera, and Diptera (˃1%) and fourth cluster composed of Blattaria, Diplura, Isoptera, and Lepidoptera (≈0%). Saranya et al (2019) who studied the diversity of predatory spider fauna in maize ecosystem used dendrogram analysis to evaluate similarity index of predatory spider families. The six spider families formed one clusters and genus formed three clusters with 25% similarity.…”