Adnan Muzaffar

Molecular and Biochemical Characterization of Cotton Epicuticular Wax in Defense Against Cotton Leaf Curl Disease

BACKGROUND Gossypium arboreumis resistant to Cotton leaf curl Burewala virus and its cognate Cotton leaf curl Multan beta satellite (CLCuBuV and CLCuMB). However, the G. arboreum wax deficient mutant (GaWM3) is susceptible to CLCuV. Therefore, epicuticular wax was characterized both quantitatively and qualitatively for its role as physical barrier against whitefly mediated viral transmission and co-related with the titer of each viral component (DNA-A, alphasatellite and betasatellite) in plants. OBJECTIVES The hypothesis was the CLCuV titer in cotton is dependent on the amount of wax laid down on plant surface and the wax composition. RESULTS Analysis of the presence of viral genes, namely alphasatellite, betasatellite and DNA-A, via real-time PCR in cotton species indicated that these genes are detectable in G. hirsutum, G. harknessii and GaWM3, whereas no particle was detected in G. arboreum. Quantitative wax analysis revealed that G. arboreum contained 183 μg.cm-2 as compared to GaWM3 with only 95 μg.cm-2. G. hirsutum and G. harknessii had 130 μg.cm-2 and 146 μg.cm-2, respectively. The GCMS results depicted that Lanceol, cis was 45% in G. harknessii. Heptadecanoic acid was dominant in G. arboreum with 25.6%. GaWM3 had 18% 1,2,-Benenedicarboxylic acid. G. hirsutum contained 25% diisooctyl ester. The whitefly feeding assay with Nile Blue dye showed no color in whiteflies gut fed on G. arboreum. In contrast, color was observed in the rest of whiteflies. CONCLUSIONS From results, it was concluded that reduced quantity as well as absence of (1) 3-trifluoroacetoxytetradecane, (2) 2-piperidinone,n-|4-bromo-n-butyl|, (3) 4-heptafluorobutyroxypentadecane, (4) Silane, trichlorodocosyl-, (5) 6- Octadecenoic acid, methyl ester, and (6) Heptadecanoicacid,16-methyl-,methyl ester in wax could make plants susceptible to CLCuV, infested by whiteflies.

Role of epicuticular waxes in the susceptibility of cotton leaf curl virus (CLCuV)

Cotton leaf curl virus (CLCuV) is the causal agent of the damaging disease of cotton that is caused by number of begomaviruses and vectored by silver leaf whitefly. In the present study, an attempt was made by infecting Gossypium arboreum variety 786, its wax mutant GaWM3 along with Gossypium hirsutum MNH-93 with viruliferous whiteflies. The presence of symptoms on leaves and amplification by PCR for virus in G. hirsutum MNH-93 and wax mutant GaWM3 but not in G. arboreum variety 786 clearly determined the presence of virus in G. hirsutum MNH-93 and wax mutant GaWM3 but not in G. arboreum variety 786. The results indicate that wax may act as physical barrier and provide hindrance in transfer of virus by whitefly.

An overview of phytochrome: An important light switch and photo-sensory antenna for regulation of vital functioning of plants

Abstract Plants are the primary source of nutrition and essential to maintain life on earth. They have evolved very delicate and advanced photo-sensory antennae to sense their outer environment and transduce the received information for their growth and development accordingly. This “light switch” phenomenon of plants has slowly being unraveled and various plant photoreceptors, their role in downstream molecular signaling, mutual interaction, response to circadian cycle and light signals have been discovered. The photosensory antennae in plants; phytochromes, cryptochromes and phototropins play a very crucial role in sensing the ambient light intensities. By direct interaction with the environment through these photosensory antennae, plants shift their homeostasis to regulate their growth and development. The phytochrome light receptors of plants are responsive to R/FR light and by inducing signaling pathways, trigger the physiological responses such as germination and flowering. The phytochromes also directly contribute to plant development by affecting its photosynthetic rate. To elucidate the role of phytochromes in plant metabolism, this review will focus on the importance of phytochromes, their mechanism of action and their application as an emerging field in plant biology.

TRANSGENIC COTTON: HARBORING BROAD TERM RESISTANCE AGAINST INSECT AND WEEDS THROUGH INCORPORATION OF CEMB DOUBLE Bt AND cp4EPSPS GENES

Introduction of multiple traits in crop plants for desirable character is an essential tool of Biotechnological application. To overcome problem of insect pests and weeds cotton variety FBS-37 was genetically modified by transformation of CEMB Cry1Ac+Cry2A and GTGene cloned in different plant expression vectors under CaMV35S Promoter and nopaline synthase Nos Terminator. CEMB optimized protocol of cotton gene transformation i.e. Agrobacterium mediated shoot apex cut method was applied for transformation of these genes constructs in cotton. Overall transformation efficiency was found to be 1.05%. Putative transgenic cotton plants were shifted to soil pots and acclimatized in the green house conditions. PCR with gene specific primers amplified 190bp for EPSPS (Glyphosate GTG) and 1000bp for each of Cry1Ac and Cry2A. Quantification of Cry1Ac, Cry2A and GTG protein through ELISA determined maximum of 0.8 µ g/g, 1 µ g/g and 0.9 µ g/g of tissue respectively. 100% mortality was obtained in 2 nd instar larvae of Heliothus armigera when compared with non-transgenic control cotton plants where maximum damaged was seen in leaf bioassay. Moreover, transgenic cotton plants successfully survived when sprayed with 1600ml/acre of glyphosate as compared to control where 100% mortality and necrosis occur after 7 days of spray assay in control conditions. Keyword: Herbicide resistant, glyphosate, Cry1Ac, GTG, weedicide resistant