scholarly journals A Personal History in Parasitic Weeds and Their Control

Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2249
Author(s):  
Chris Parker

This invited paper summarises a career in which I became increasingly involved in research and related activities on Striga and other parasitic weeds. It also presents a personal view of the present status of parasitic weed problems and their control.

1981 ◽  
Vol 17 (4) ◽  
pp. 415-418 ◽  
Author(s):  
F. F. Bebawi ◽  
A. F. Farah

SUMMARYThe parasitic weed striga had significantly greater effects on sorghum yield components than non-parasitic weeds. Grain reduction caused by striga amounted to 65% compared with 32% reduction caused by non-parasitic weeds. Comparable reductions were also manifest in straw yield, grains/head and plant height of sorghum. Early removal of striga (a week after its emergence), and thereafter at regular weekly intervals, may help to improve crop yields.


2019 ◽  
pp. 137-147
Author(s):  
Elena Spirovska

This paper attempts to explore the aspects of reviewing personal history and analyzing personal identity presented in Margaret Atwood’s novel The Handmaid’s Tale. Offred’s story, which is presented to the reader as a written narrative reconstructed from tapes two centuries after her death and the end of the dictatorship of Gilead, are discussed at a scientific conference held on June 25, 2195. As a Handmaid in a service of Commander Waterford and a prisoner in his household, Offred‘s identity, her past and even her first name are taken away from her. Her role is limited to a child bearer only. Throughout the novel, Offred rethinks her former life, her tendency to live by ignoring, to take everything for granted and to trust fate. She remembers the days in the pre-Gilead society, where freedom to do something is replaced with freedom from doing in Gilead. She reviews her relationship with her mother and her attitude towards her mother’s values and feminism. She recollects her relationship with her husband, her role as a mother and her way of life in the pre-Gilead society. Offred compares her previous and her present status in a situation in which her personal freedom is almost non-existent. In her newly-discovered self- awareness, she finds ways to redefine herself as a woman, as a lover and even as a victim.


1987 ◽  
Vol 2 (3) ◽  
pp. 203-206
Author(s):  
Fumihiko Mori

This paper gives the personal view of a Japanese knowledge engineer, concerning the present status of the evolution of knowledge engineering in Japan, especially its applications in the business field, user evaluation and acceptance, problems, and future prospects.


2018 ◽  
Vol 211 ◽  
pp. 643-660 ◽  
Author(s):  
Artem R. Oganov

In these Concluding Remarks, I try to summarize my personal view of the enormous progress made in the field of CSP and the open questions and challenges that keep this field more exciting than ever.


2021 ◽  
Author(s):  
Atsushi Okazawa ◽  
Atsusya Baba ◽  
Hikaru Okano ◽  
Tomoya Tokunaga ◽  
Tsubasa Nakaue ◽  
...  

Root parasitic weeds of the Orobanchaceae, such as witchweeds (Striga spp.) and broomrapes (Orobanche and Phelipanche spp.), cause serious losses in agriculture worldwide. No practical method to control these parasitic weeds has been developed to date. Understanding the characteristic physiological processes in the life cycles of root parasitic weeds is particularly important to identify specific targets for growth modulators. In our previous study, planteose metabolism was revealed to be activated soon after the perception of strigolactones in germinating seeds of O. minor. Nojirimycin inhibited planteose metabolism and impeded seed germination of O. minor, indicating that planteose metabolism is a possible target for root parasitic weed control. In the present study, we investigated the distribution of planteose in dry seeds of O. minor by matrix-assisted laser desorption/ionization—mass spectrometry imaging. Planteose was detected in tissues surrounding—but not within—the embryo, supporting its suggested role as a storage carbohydrate. Biochemical assays and molecular characterization of an α-galactosidase family member, OmAGAL2, indicated the enzyme is involved in planteose hydrolysis in the apoplast around the embryo after the perception of strigolactones to provide the embryo with essential hexoses for germination. These results indicated that OmAGAL2 is a potential molecular target for root parasitic weed control.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vinay Kumar Bari ◽  
Jackline Abu Nassar ◽  
Radi Aly

AbstractRoot parasitic weeds infect numerous economically important crops, affecting total yield quantity and quality. A lack of an efficient control method limits our ability to manage newly developing and more virulent races of root parasitic weeds. To control the parasite induced damage in most host crops, an innovative biotechnological approach is urgently required. Strigolactones (SLs) are plant hormones derived from carotenoids via a pathway involving the Carotenoid Cleavage Dioxygenase (CCD) 7, CCD8 and More Axillary Growth 1 (MAX1) genes. SLs act as branching inhibitory hormones and strictly required for the germination of root parasitic weeds. Here, we demonstrate that CRISPR/Cas9-mediated targted editing of SL biosynthetic gene MAX1, in tomato confers resistance against root parasitic weed Phelipanche aegyptiaca. We designed sgRNA to target the third exon of MAX1 in tomato plants using the CRISPR/Cas9 system. The T0 plants were edited very efficiently at the MAX1 target site without any non-specific off-target effects. Genotype analysis of T1 plants revealed that the introduced mutations were stably passed on to the next generation. Notably, MAX1-Cas9 heterozygous and homozygous T1 plants had similar morphological changes that include excessive growth of axillary bud, reduced plant height and adventitious root formation relative to wild type. Our results demonstrated that, MAX1-Cas9 mutant lines exhibit resistance against root parasitic weed P. aegyptiaca due to reduced SL (orobanchol) level. Moreover, the expression of carotenoid biosynthetic pathway gene PDS1 and total carotenoid level was altered, as compared to wild type plants. Taking into consideration, the impact of root parasitic weeds on the agricultural economy and the obstacle to prevent and eradicate them, the current study provides new aspects into the development of an efficient control method that could be used to avoid germination of root parasitic weeds.


1978 ◽  
Vol 48 ◽  
pp. 175-178 ◽  
Author(s):  
K. J. Johnston
Keyword(s):  

A summary of results for radio astrometry with baselines ≤ 35 km and priorities for future work are given.


Sign in / Sign up

Export Citation Format

Share Document