• The Plant Pathology Journal
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• v.20 no.2
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• pp.81-84
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• 2004

Branched broomrape (Orobanche ramosa) is a holo-parasitic flowering plant that attaches to the root of its host, green plant, by means of a specialized structure known as haustorium. Following successful contact and penetration on susceptible plant root, complex tissue of Orobanche cells is formed which is known as the tubercle. Newly formed tubercles contain high activity ofindole-3-acetic acid (IAA). Triiodobenzoic acid (TIBA), as an inhibitor of IAA polar transport, was utilized to investigate the supply and requirement of auxin to the developing O. ramosa on tomato plant. There was no significant reduction in the incidence of O. ramosa per pot of different TIBA treatments. However, infection severity in terms of the number of O. ramosa shoots that emerged per plant and number of attachments per plant root system were significantly reduced by 60 % and 45 % on TIBA treated plants, respectively. Histo-logical studies revealed conspicuous delay in the initiation of xylem vessel differentiation inside tubercles of the TIBA treated tomato plants. Also, differentiated vessels showed thinner secondary wall deposition, and improper alignment within bundles inside those tubercles. They were wider and shorter in diameter in comparison to those of untreated plants. These findings were attri-buted to the short supply of IAA required for normal development, and to the xylem vessel differentiation of O. ramosa tubercles on infected tomato. Hence, this parasitic flowering plant seems to depend upon its host in its requirements for IAA, in a source to sink relation-ship.

• Korean Journal of Plant Taxonomy
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• v.53 no.1
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• pp.65-68
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• 2023

The herb Pedicularis cheilanthifolia var. albida (Pennell) P. C. Tsoong is reported and collected for the first time from the Rudraprayag District of Uttarakhand. The species was seen growing along a glacial stream in an alpine region between 4,100 and 4,400 m asl. Morphological characteristics of the species were examined and processed for herbarium deposition. To simplify taxon identification, a brief taxonomic description and illustration of the taxon are provided.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.148-151
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• 2003

Seeds of broomrape (Orobanche cernua) were exposed to 0, 25, 50, 75, and 100 mM NaCl solutions during their preconditioning period (14 days of moisture) under laboratory conditions and induced to germinate by synthetic germination stimulant (GR24). There was significant reduction in seed germination with increased salt concentration as shown in 35.2, 32.5, 23.6, 14.3, and 9.2% germination, respectively. Exposure of Orobanche cernua seeds to 0.0, 1.0, 1.25, and 1.5 M levels of NaCl for 9 hours resulted in 29.4, 21.3, 20.5, and 17.4% germination, respectively. Water preconditioned seeds showed Heavier protein profile bands of 6.5-14.2 KDa than those of dry seeds. Seeds treated with 0.75 M NaCl showed profile similar with that of water preconditioned ones, plus an extra band at 29-36 KDa. The protein profiles of 1.0 and 1.5 M NaCl treated seeds showed weaker bands with the absence of 29-36 KDa band.

• The Plant Pathology Journal
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• v.21 no.4
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• pp.391-394
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• 2005

Tomato seedlings (20- days old) were transplanted to infested soil with Orobanche cernua and non-infested soils. All plants were maintained under 0, 25, 50 and 75 mM NaCl soil salinity levels throughout their growing period under greenhouse conditions. Plants grown in O. cernua infested soil infIltrated with 0, 25, and 50 mM NaCl solution for salinity showed significant reduction in their growth as well as their total soluble carbohydrate and protein contents in compared with those grown in non-infested soil. However, under 75 mM NaCI salinity level all plants showed similar growth values whether they were grown in O. cernua infested or non-infested soil. Starting at the fifth and through out the eighth week after transplantation there was a significant increase in plant height in the 0, 25 and 50 mM NaCl irrigated plants over other treatments. Irrigation with 50 mM NaCl significantly reduced the emergence of O. cernua (2/plant) and the number of attachments (4.4 attachments) on roots of tomato. Furthermore, irrigation with 75 mM NaCl resulted in complete elimination of O. cernua emergence.

• The Plant Pathology Journal
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• v.37 no.6
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• pp.512-520
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• 2021

In this study, we report genetic characterization of Orobanche cumana, the causal agent of sunflower wilting in Serbia. The genetic diversity of this parasitic plant in Serbia was not studied before. Random amplified polymorphic DNA (RAPD) markers and partial rbcL gene sequences analysis were used to characterize the O. cumana populations at the molecular level. While phylogenetic analyses of RAPD-PCR amplicons were performed using unweighted pair-group Method analyses, rbcL gene sequences were analyzed using neigbor joining method and minimum spanning tree. Molecular analyses of RAPD-PCR analysis revealed high genetic diversity of O. cumana populations which indicated high adaptive potential of this parasitic weed in Serbia. Further analyses of rbcL gene using minimum spanning tree revealed clear differences among diverse sections of Orobanche genus. Although this molecular marker lacked the resolution to display intrapopulation diversity it could be a useful tool for understanding the evolution of this parasitic plant. Our results suggested that O. cumana has great genetic potential which can lead to differentiation of more virulent races which is important for determining crop breeding strategies for their control.