Role of Pepper (Capsicum annuum) as a Trap and Catch Crop for Control of Orobanche aegyptiaca and O. cernua

Weed Science ◽  
1996 ◽  
Vol 44 (4) ◽  
pp. 948-951 ◽  
Author(s):  
Joseph Hershenhorn ◽  
Yaakov Goldwasser ◽  
Dina Plakhine ◽  
Geza Herzlinger ◽  
Shmuel Golan ◽  
...  

The response of pepper varieties to Egyptian broomrape and nodding broomrape was characterized in comparison with tomatoes grown in pots and in aqueous solution, according to two criteria: 1. germination of the parasite's seeds in the presence of the host roots; and 2. the number of parasites per host plant. More than 50% of Egyptian broomrape seeds germinated in the presence of all pepper variety roots except the sweet pepper Maor. However, only a few attached and developed. The two paprika varieties Lehava and Shani were hosts to more parasites than the sweet pepper varieties, and showed as many as 15 parasites per host plant. In contrast, tomato roots induced less then 10% seed germination but were highly susceptible to the parasite (30 parasites per host plant). Damage caused to pepper foliage and fruit was not significant, compared to the heavy damage caused to tomato. Pepper roots stimulated germination of 22 to 26% of nodding broomrape seeds but without the formation of parasitic attachments, whereas tomato roots stimulated germination of less than 10% of the seeds but the plants were then heavily damaged by the parasite. Interplanting of tomato with pepper in nutrient solution did not change the amount of Egyptian broomrape parasites on pepper, hut a fourfold increase in the number of nodding broomrape was observed on tomato roots, compared to the number of parasites on tomato roots when planted without pepper.

Plants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1182
Author(s):  
Yaakov Goldwasser ◽  
Onn Rabinovitz ◽  
Zev Gerstl ◽  
Ahmed Nasser ◽  
Amit Paporisch ◽  
...  

Parasitic plants belonging to the Orobanchaceae family include species that cause heavy damage to crops in Mediterranean climate regions. Phelipanche aegyptiaca is the most common of the Orobanchaceae species in Israel inflicting heavy damage to a wide range of broadleaf crops, including processing tomatoes. P. aegyptiaca is extremely difficult to control due to its minute and vast number of seeds and its underground association with host plant roots. The highly efficient attachment of the parasite haustoria into the host phloem and xylem enables the diversion of water, assimilates and minerals from the host into the parasite. Drip irrigation is the most common method of irrigation in processing tomatoes in Israel, but the delivery of herbicides via drip irrigation systems (herbigation) has not been thoroughly studied. The aim of these studies was to test, under laboratory and greenhouse conditions, the factors involved in the behavior of soil-herbigated imazapic, and the consequential influence of imazapic on P. aegyptiaca and tomato plants. Dose-response Petri dish studies showed that imazapic does not impede P. aegyptiaca seed germination and non-attached seedlings, even at the high rate of 5000 ppb. Imazapic applied to tomato roots inoculated with P. aegyptiaca seeds in a PE bag system revealed that the parasite is killed only after its attachment to the tomato roots, at concentrations as low as 2.5 ppb. Imazapic sorption curves and calculated Kd and Koc values indicated that the herbicide Kd is similar in all soils excluding a two-fold higher coefficient in the Gadash farm soil, while the Koc was similar in all soils except the Eden farm soil, in which it was more than twofold lower. In greenhouse studies, control of P. aegyptiaca was achieved at >2.5 ppb imazapic, but adequate control requires repeated applications due to the 7-day half-life (t1/2) of the herbicide in the soil. Tracking of imazapic in soil and tomato roots revealed that the herbicide accumulates in the tomato host plant roots, but its movement to newly formed roots is limited. The data obtained in the laboratory and greenhouse studies provide invaluable knowledge for devising field imazapic application strategies via drip irrigation systems for efficient and selective broomrape control.


1998 ◽  
Vol 12 (1) ◽  
pp. 108-114 ◽  
Author(s):  
Joseph Hershenhorn ◽  
Dina Plakhine ◽  
Yaakov Goldwasser ◽  
James H. Westwood ◽  
Chester L. Foy ◽  
...  

The effect of the sulfonylurea herbicides, bensulfuron, chlorsulfuron, nicosulfuron, primisulfuron, rimsulfuron, thifensulfuron, and triasulfuron, on seed germination and radicle elongation of the parasitic plant, Egyptian broomrape, was tested in vitro without a host plant. These herbicides applied to the seeds at the preconditioning and germination stages significantly reduced radicle elongation of the parasite. Chlorsulfuron, rimsulfuron, and triasulfuron were further tested in polyethylene bags, where the parasite was able to parasitize tomato roots. Chlorsulfuron and triasulfuron applied at 2.5 and 25 μM ai and rimsulfuron at 5.0 μM ai, at the preconditioning and germination stages, almost completely inhibited parasite development, but at lower concentrations the parasite partially recovered 26 days after application. Chlorsulfuron inhibited parasite development for 34 d. Chlorsulfuron, triasulfuron, and rimsulfuron damaged parasite organs and caused rapid death of Egyptian broomrape tubercles when applied after the parasite had completed attachment to host roots. However, chlorsulfuron and triasulfuron at 25 μM ai were toxic to the tomato plants.


ChemPhysChem ◽  
2008 ◽  
Vol 9 (9) ◽  
pp. 1309-1316 ◽  
Author(s):  
Hao Zhang ◽  
Yi Liu ◽  
Chunlei Wang ◽  
Junhu Zhang ◽  
Haizhu Sun ◽  
...  

2005 ◽  
Vol 7 (1) ◽  
pp. 44-54 ◽  
Author(s):  
Jessica M. Gill ◽  
Sarah L. Szanton ◽  
Gayle G. Page

Women develop posttraumatic stress disorder (PTSD) at twice the rate of men, even though fewer women than men experience traumatic events over their lifetimes. Current studies of individuals with PTSD provide evidence of alterations in the neuroendocrine system that involve levels and activity of cortisol and DHEA and changes in immune function that predispose these individuals toward an innate (Th1) immune response. Yet few studies have addressed the possible role of these biologic alterations in women’s increased vulnerability to developing PTSD. In addition, current studies are limited in their ability to link biologic alterations to the observed fourfold increase in medical conditions in women with PTSD as compared to women without PTSD. And finally, few studies have addressed the biologic impact of co-occurring major depressive disorder (MDD) in individuals with PTSD. This critical review provides an update on neuroendocrine and immune perturbations associated with PTSD with and without cooccurring MDD to suggest links to health and possible mechanisms underlying the observed sex disparity in the development of PTSD.


2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Stefan Lis ◽  
Krzysztof Staninski ◽  
Tomasz Grzyb

The europium (III) complex of coumarin-3-carboxylic acid (C3CA) has been prepared and characterized on the basis of elemental analysis, IR, and emission (photoluminescence and electrochemiluminescence) spectroscopy. The synthesised complex having a formula Eu was photophysically characterized in solution and in the solid state. Electrochemiluminescence, ECL, of the system containing the Eu(III)/C3CA complex was studied using an oxide-covered aluminium electrode. The goal of these studies was to show the possibility of the use of electrochemical excitation of the Eu(III) ion in aqueous solution for emission generation. The generated ECL emission was very weak, and therefore its measurements and spectral analysis were carried out with the use of cut-off filters method. The studies proved a predominate role of the ligand-to-metal energy transfer (LMET) in the generated ECL.


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