The WRKY gene family has never been identified in pigeonpea (Cajanus cajan). Therefore, objective of the present study was to identify the WRKY gene family in pigeonpea and characterize the Fusarium udum stress-responsive WRKY genes under normal, NaCl-stressed and Pseudomonas fluorescens OKC (a plant growth-promoting bacterial strain) treated conditions. The aim was to characterize the Fusarium udum stress-responsive WRKY genes under some commonly occurring field conditions. We identified 97 genes in the WRKY family of pigeonpea, using computational prediction method. The gene family was then classified into three groups through phylogenetic analysis of the homologous genes from the representative plant species. Among the 97 identified WRKY genes 35 were further classified as pathogen stress responsive genes. Functional validation of the 35 WRKY genes was done through generating transcriptional profiles of the genes from root tissues of pigeonpea plants under the influence of P. fluorescens OKC after 24 h of stress application (biotic: Fusarium udum, abiotic: NaCl). The entire experiment was conducted in two pigeonpea cultivars Asha (resistant to F. udum) and Bahar (susceptible to F. udum) and the results were concluded on the basis of transcriptional regulation of the WRKY genes in both the pigeonpea cultivars. The results revealed that among the 35 tentatively identified biotic stress responsive CcWRKY genes, 26 were highly F. udum responsive, 17 were better NaCl responsive compared to F. udum and 11 were dual responsive to both F. udum and NaCl. Application of OKC was able to enhance transcript accumulation of the individual CcWRKY genes to both the stresses when applied individually but not in combined challenge of the two stresses. The results thus indicated that CcWRKY genes play a vital role in the defense signaling against F. udum and some of the F. udum responsive CcWRKYs (at least 11 in pigeonpea) are also responsive to abiotic stresses such as NaCl. Further, plant beneficial microbes such as P. fluorescens OKC also help pegionpea to defend itself against the two stresses (F. udum and NaCl) through enhanced expression of the stress responsive CcWRKY genes when the stresses are applied individually.
2000)Light and sem studies on the life stages of illeis indica (TIMB.) and its predatism on phyllactinia corylea (PERS.) karst. infecting mulberry, Archives of Phytopathology and Plant Protection, 33:2, 149-159,The fungivonis insect Illeis indica is a potential biocontrol agent of Phyllactinia corylea which causes powdery mildew in mulberry. The present study by light and scanning electron microscopy explains the life stages of I. indica and its feeding behaviour on P. corylea borne on infected mulberry leaves. The eggs are laid in clusters of 5-23 on the abaxial surface of infected leaves. Each egg has 16-18 aeropyles circularly arranged at its distal end around a micropylar plate. Total larval period of I. indica is about 15.60 days with four instars and its life cycle is completed in 38.50 days. The grubs feed only on conidia during first instar, on conidia and conidiophores during second instar, and also on parts of mycelia during third instar. The final instar grubs feed on entire aerial mycelial mass leaving only stomatopodia and hyphal remnants attached to them. Pupation is for 6-7 days and the pupae remain motionless and attached to the abaxial leaf surface. Adults also feed voraciously on the fungal mass and the fertilized females lay eggs after about 7.03 ±0.144 days. The grubs and adults clear off the fungal mass from the infected leaves without leaving any mycelial patch and the fungus does not regenerate on such cleared leaves. Field observations indicated a drastic fall in the incidence of powdery mildew disease in mulberry even in the usual peak disease period, with the increased population of I. indica in the mulberry garden.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.